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Cited by 1,221Fermentation and Sensory AnalysisHorticultural and Viticultural ResearchBiochemical and biochemical processes

Yeast and bacterial modulation of wine aroma and flavour

Open access
SWIEGERS, J.H., BARTOWSKY, E.J., HENSCHKE, P.A., PRETORIUS, I.S.·2005·Australian Journal of Grape and Wine Research
DOI 10.1111/j.1755-0238.2005.tb00285.x
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Abstract

Wine is a highly complex mixture of compounds which largely define its appearance, aroma, flavour and mouth-feel properties. The compounds responsible for those attributes have been derived in turn from three major sources, viz. grapes, microbes and, when used, wood (most commonly, oak). The grape-derived compounds provide varietal distinction in addition to giving wine its basic structure. Thus, the floral monoterpenes largely define Muscat-related wines and the fruity volatile thiols define Sauvignon-related wines; the grape acids and tannins, together with alcohol, contribute the palate and mouth-feel properties. Yeast fermentation of sugars not only produces ethanol and carbon dioxide but a range of minor but sensorially important volatile metabolites which gives wine its vinous character. These volatile metabolites, which comprise esters, higher alcohols, carbonyls, volatile fatty acids and sulfur compounds, are derived from sugar and amino acid metabolism. The malolactic fermentation, when needed, not only provides deacidification, but can enhance the flavour profile. The aroma and flavour profile of wine is the result of an almost infinite number of variations in production, whether in the vineyard or the winery. In addition to the obvious, such as the grapes selected, the winemaker employs a variety of techniques and tools to produce wines with specific flavour profiles. One of these tools is the choice of microorganism to conduct fermentation. During alcoholic fermen…

Integrity signals

Registry

Crossref · 10.1111/j.1755-0238.2005.tb00285.x

Cites

172 of 172 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

16 of 354 cited sources checked · 2 supported · 0 flagged · accuracy not yet measured

  • Premisecitation

    This transamination reaction is catalysed inside the yeast by mitochondrial and cytosolic branched-chain amino acid aminotransferases encoded by BAT1 and BAT2.

    “This reaction is catalysed inside the yeast by mitochondrial and cytosolic branched-chain amino acid aminotransferases encoded by BAT1 and BAT2 (Eden et al. 1996, 2001, Kispal et al. 1996).”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites Eden et al. 1996 source
    • cites Kispal et al. 1996 source
  • Findingcitation

    Cells undergoing autolysis after fermentation can release hydrogen sulfide.

    “Cells which undergo autolysis after fermentation can also release hydrogen sulfide (Suomalainen and Lehtonen 1979).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Suomalainen and Lehtonen 1979 source

      The Sulphur compounds section says that sulphur compounds are produced through autolysis of amino acids in yeast cell proteins. It also says hydrogen sulphide forms during fermentation, but does not specifically say that cells autolysing after fermentation release it. No page number is available in our copy. (LLM, conf=0.84)

      Experimental — accuracy not yet measured
  • Findingcitation

    Cell-free enzyme extract of Eubacterium limosum containing carbon-sulfur lyases can release 4MMP from Cys-4MMP.

    “A mechanism of thiol release was proposed on the basis of experiments showing that a cell-free enzyme extract of the bacteria Eubacterium limosum containing carbon-sulfur lyase enzymes can release 4MMP from its precursor S-4-(4-methylpentan-2-one)-L-cysteine (Cys-4MMP) (Tominaga et al. 1995).”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites Tominaga et al. 1995 source
  • Premisecitation

    Sulfite reductase is a heterotetramer of two α and two β subunits encoded by MET10 and MET5.

    “Sulfite reductase is a heterotetramer, consisting of two αand two β-subunits, which are encoded by MET10 and MET5 genes, respectively (Kobayashi and Yoshimoto 1982, Hansen et al. 1994, Sutherland et al. 2003).”
    Quote in the paperSubstantial claim1 of 3 sources checked
    • cites Kobayashi and Yoshimoto 1982

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Hansen et al. 1994 source

      The introduction reports that earlier results suggested an α2β2 structure, and the paper identifies MET10 as encoding the α subunit. It says the size of MET5 mRNA suggests MET5 might encode the β subunit; it does not establish that assignment or the subunit arrangement as fact. (LLM, conf=0.87)

      Experimental — accuracy not yet measured
    • cites Sutherland et al. 2003

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Premisecitation

    Mannitol can serve as a sole carbon source for the homofermentative lactic acid bacteria Lactobacillus plantarum.

    “Mannitol can serve as a sole carbon source for the homofermentative lactic acid bacteria Lactobacillus plantarum (Davis et al. 1988, Liu et al. 1995, Wisselink et al. 2002).”
    Quote in the paperNot a substantial claim1 of 3 sources checked
    • cites Davis et al. 1988 source
    • cites Liu et al. 1995

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Wisselink et al. 2002 source

      The available passages are bibliographic information and do not address whether Lactobacillus plantarum can use mannitol as its sole carbon source. Searches for that claim, including “sole carbon source” and mannitol utilization, returned no relevant passage from the paper. (LLM, conf=0.70)

      Experimental — accuracy not yet measured
  • May combine two claims. 101
  • Classified as probably not a substantial claim. 27

  • May combine two claims.

    Premisecitation

    Succinic and keto acids are present only in trace amounts in grapes, but concentrations are higher in wines as a result of fermentation.

    “succinic and keto acids are present only in trace amounts in grapes, but concentrations are higher in wines as a result of fermentation (Whiting 1976, Fowles 1992, Radler 1993, Boulton et al. 1998).”
    Quote in the paperNot a substantial claim1 of 3 sources checked
    • cites Whiting 1976 source

      The Succiiiic acid section says yeasts excrete succinate during fermentation and gives concentrations for finished wines. The Introduction likewise says yeasts excrete keto (oxo) acids during fermentation and reports their concentrations in wines. These passages support fermentation as a source of the acids in wine, but they do not establish that both are present only in trace amounts in grapes or directly compare grape and wine concentrations. Page numbers were not supplied for these passages. (LLM, conf=0.84)

      Experimental — accuracy not yet measured
    • cites Fowles 1992 source
    • cites Radler 1993

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Succinic acid has been reported to have an unusual salty, bitter taste in wine.

    “Succinic acid has been reported to have an 'unusual salty, bitter taste' in wine (Whiting 1976).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Whiting 1976 source

      The 'Succinic acid' section (page not provided) reports that succinate occurs in wine, but does not describe its taste. Searches for 'salty,' 'bitter,' and taste-related terms found no passage in our copy supporting the attributed sensory description. (LLM, conf=0.74)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Tartaric acid and malic acid are the predominant non-volatile organic acids, accounting for 90% of the titratable acidity of grape juice.

    “The predominant non-volatile organic acids are tartaric acid and malic acid, accounting for 90% of the titratable acidity (TA) of grape juice.”
    Quote in the paperNot a substantial claim1 of 3 sources checked
    • cites Whiting 1976 source

      The Tartaric acid section discusses tartrate formation by wine yeasts, and the passage on malate breakdown discusses malate in grape juice. Neither states that tartaric and malic acids predominate in grape juice or that they account for 90% of its titratable acidity. Searches for the 90% figure and for the major acids in grape juice found no passage addressing those points. (LLM, conf=0.71)

      Experimental — accuracy not yet measured
    • cites Fowles 1992 source
    • cites Radler 1993

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Red wines typically have higher concentrations of glycerol than white wines.

    “Red wines typically have higher concentrations of glycerol than white wines (6.82 g/L versus 10.49 g/L; Nieuwoudt et al. 2002)”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Nieuwoudt et al. 2002 source

      The wine-style results (p. 3) report higher mean glycerol in dry red wine (10.49 g/L) than in dry white wine (6.82 g/L), supporting the main claim. The citing sentence lists the two values in the opposite order, which, if read as red versus white, assigns them to the wrong wines. (LLM, conf=0.85)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    Acetaldehyde increases with increasing fermentation temperature: a fermentation carried out at 30oC resulted in a significantly higher concentration of acetaldehyde.

    “Acetaldehyde also increases with increasing fermentation temperature: e.g. a fermentation carried out at 30ºC resulted in a significantly higher concentration of acetaldehyde (Romano et al. 1994).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Romano et al. 1994 source

      The ‘Influence of fermentation temperature’ section reports that acetaldehyde production increased considerably at 30°C, supporting the example. It also says production was unaffected at 12°C, 18°C, and 24°C, so the broader claim that it increases with each increase in fermentation temperature overstates the finding. The supplied passage does not report a statistical significance test. (LLM, conf=0.86)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Botrytised wines frequently have glycerol concentrations up to 25 g/L.

    “botrytised wines frequently have concentrations up to 25 g/L (Rankine and Bridson 1971, Ough et al. 1972, Nieuwoudt et al. 2002).”
    Quote in the paperNot a substantial claim1 of 3 sources checked
    • cites Rankine and Bridson 1971 source
    • cites Ough et al. 1972 source
    • cites Nieuwoudt et al. 2002 source

      The introduction (p. 1) reports glycerol levels of 14.6–24.7 g/L in botrytised German and French wines, supporting the approximate upper value of 25 g/L. It calls those levels “exceptionally high,” however, and does not establish that concentrations near 25 g/L occur frequently. (LLM, conf=0.84)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    In general, the homofermentative lactic acid bacteria will only produce small amounts of mannitol, whereas some heterofermentative lactic acid bacteria produce and export substantial amounts of mannitol.

    “In general, the homofermentative lactic acid bacteria will only produce small amounts of mannitol, whereas some heterofermentative lactic acid bacteria produce and export substantial amounts of mannitol (Wisselink et al. 2002).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Wisselink et al. 2002 source

      The indexed copy’s Abstract says several heterofermentative lactic acid bacteria produce large amounts of mannitol, while homofermentative bacteria produce only small amounts. It does not say that the heterofermentative bacteria export the mannitol, so that part of the attributed claim is unsupported. (LLM, conf=0.86)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingcitation

    TDN is thought present in other wine varieties below threshold.

    “It is thought that TDN is also present in other wine varieties, although at concentrations below its threshold (Etiévant 1991, Ribéreau-Gayon et al. 2000b, Marais et al. 1992, Simpson and Miller 1983).”
    Quote in the paperNot a substantial claim1 of 3 sources checked
    • cites Etiévant 1991

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Ribéreau-Gayon et al. 2000b

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Marais et al. 1992 source

      The Results and Discussion (p. 2) examine Weisser Riesling wines, and the Conclusions (p. 6) discuss TDN in that variety. Our copy does not say whether TDN is present in other wine varieties or whether its concentrations there are below a threshold (searched for other varieties and threshold). (LLM, conf=0.75)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    Yeast and bacteria contribute to the diacetyl content of wine, though the concentration of diacetyl produced by yeast during alcoholic fermentation is usually below its detection threshold.

    “Yeast and bacteria contribute to the diacetyl content of wine (Figure 10), though the concentration of diacetyl produced by yeast during alcoholic fermentation is usually below its detection threshold (Martineau and Henick-Kling 1995).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Martineau and Henick-Kling 1995 source

      The Introduction says diacetyl accumulates during alcoholic fermentation and is synthesized by lactic acid bacteria during malolactic fermentation. It does not say that the amount produced by yeast is usually below the detection threshold; the Results and Discussion instead show that thresholds vary by wine type. No page numbers are available in our copy. (LLM, conf=0.85)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    Esters can also be derived from the grape, from the chemical esterification of alcohols and from acids during wine ageing.

    “Esters can, however, also be derived from the grape, from the chemical esterification of alcohols and from acids during wine ageing (Rapp and Mandery 1986, Etiévant 1991, Younis and Stewart 1998, Lambrechts and Pretorius 2000).”
    Quote in the paperNot a substantial claim1 of 3 sources checked
    • cites Rapp and Mandery 1986 source
    • cites Etiévant 1991

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Younis and Stewart 1998 source

      The Introduction says esters can form through a reaction between a carboxylic acid and an alcohol, supporting the chemical-esterification part of the claim. It does not address esters originating in grapes or forming during wine ageing; its discussion of reaction rates concerns beer. Page numbers are unavailable in our copy. (LLM, conf=0.88)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Findingcitation

    Disulfides can be reduced to mercaptans by sulfite ions, which can then be removed by copper or silver fining.

    “Disulfides can be reduced to mercaptans by the action of sulfite ions, which can then be removed by copper or silver (not permitted in some countries) fining (Bobet et al. 1990).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Bobet et al. 1990 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingcitation

    Ethanethiol can be formed by reaction of hydrogen sulfide with ethanol or acetaldehyde.

    “For example, mercaptans such as ethanethiol can be formed by the reaction of hydrogen sulfide with ethanol or acetaldehyde (Amerine et al. 1980, Rauhut 1993).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Amerine et al. 1980

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Rauhut 1993

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingcitation

    Ethyl mercaptan aroma is described as onion/rubber with threshold 1.1 μg/L in wine.

    “The aroma of ethyl mercaptan is described as 'onion' or 'rubber' with a threshold value of 1.1 µg/L in wine (Goniak and Noble 1987).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Goniak and Noble 1987 source

  • May combine two claims.

    Findingcitation

    In uninoculated fermentations, non-Saccharomyces yeasts become inhibited by increasing ethanol, lose viability, and presumably autolyse during early to mid fermentation.

    “These yeasts become inhibited by the increasing concentration of ethanol, lose viability and presumably autolyse during the early to mid phases of fermentation (Henschke andJiranek 1991, Fleet andHeard 1993).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Henschke andJiranek 1991

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Fleet andHeard 1993

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Findingcitation

    4MMP and 3MH exist in grapes as non-volatile cysteine-bound conjugates, and yeast cleave the thiol from the precursor.

    “However, it has been shown that 4MMP and 3MH do exist in the grapes but in the form of non-volatile, cysteine bound conjugates and that yeast are responsible for the cleaving of the thiol from the precursor (Darriet et al. 1995).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Darriet et al. 1995 source

  • May combine two claims.

    Findingcitation

    Thioacetic acid esters of mercaptans form during fermentation and slowly hydrolyse to parent mercaptan later.

    “Thioacetic acid esters of these mercaptans are also observed to form during fermentation, and these can slowly hydrolyse to the parent mercaptan at a later stage (Rauhut et al. 1996).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Rauhut et al. 1996

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Findingcitation

    4MMP, 3MH, and 3MHA have been identified in wines from Colombard, Riesling, Semillon, Merlot, and Cabernet Sauvignon in varying concentrations and can potentially impact aroma.

    “However, 4MMP, 3MH and 3MHA have also been identified in wines made from Colombard, Riesling, Semillon, Merlot and Cabernet Sauvignon in varying concentrations and can, therefore, potentially impact the aroma (Tominaga et al. 2000a, Murat et al. 2001b).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Tominaga et al. 2000a

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Murat et al. 2001b

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Findingcitation

    Hydrogen sulfide production can be affected by high residual elemental sulfur, presence of sulfur dioxide, presence of sulfur-containing organic compounds, pantothenate deficiency, high threonine relative to other amino acids, and relative methionine to ammonium concentrations.

    “Other environmental factors that can affect hydrogen sulfide production include: (i) high residual levels of elemental sulfur; (ii) presence of sulfur dioxide; (iii) presence of sulfur-containing organic compounds; (iv) pantothenate deficiency; (v) high threonine content relative to other amino acids; and (vi) relative methionine to ammonium concentrations (Monk 1986, Henschke and Jiranek 1991, R”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Monk 1986

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Henschke and Jiranek 1991

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Rauhut 1993

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingcitation

    Furfurylthiol has perception threshold 0.4 ng/L and is found in roasted coffee, meat, wheat bread, popcorn.

    “Furfurylthiol has also been found in roasted coffee, meat, wheat bread and popcorn, with a perception threshold of 0.4 ng/L (Tominaga et al. 2000b).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Tominaga et al. 2000b

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Findingcitation

    Commercial wine yeast and non-Saccharomyces yeasts tested under identical physiological conditions have the same growth characteristics but vary in sulfite reductase activity.

    “Mendes-Ferreira et al. (2002) recently screened a large selection of commercial wine yeast, in addition to non-Saccharomyces yeasts, which, when tested under identical physiological conditions, all had the same growth characteristics but varied in sulfite reductase (the enzyme producing hydrogen sulfide) activity.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Mendes-Ferreira et al. 2002

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Findingcitation

    Aliphatic/cyclic alcohols, C13-norisoprenoids, and volatile phenols like vanillin are possible precursors.

    “Aliphatic or cyclic alcohols, such as hexanol, 2-phenylethanol, benzylalcohol, C 13 -norisoprenoids and and volatile phenols such as vanillin are also possible precursors (Günata et al. 1985, Park andNoble 1993).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Günata et al. 1985

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Park andNoble 1993

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Findingcitation

    D. pseudopolymorphus β-glucosidase optimum pH 2.5-3.8, high substrate affinity, large aglycone-substrate recognition.

    “Its optimum pH lies within the wine spectrum (pH 2.5-3.8), and it has high substrate affinity and large aglycone-substrate recognition.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Cordero Otero et al. 2003 source

  • May combine two claims.

    Findingcitation

    High nitrogen (400 vs 180 mg N/L) stimulated fermentation rate but not biomass yield, and stimulated monoterpene production.

    “High nitrogen -400 mg N/L compared with 180 mg N/L -which stimulated fermentation rate but not biomass yield, also stimulated monoterpene production.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Carrau et al. 2005 source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingcitation

    Geraniol rose-like, linalool rose, linalool oxides camphorous, nerol oxides vegetative.

    “Geraniol has aromas described as rose-like and linalool aromas described as rose, whereas linalool oxides are described as camphorous and nerol oxides as vegetative (Simpson 1979).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Simpson 1979

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingcitation

    V. vinifera and Humulus lupulus produce monoterpenoids.

    “In particular, two of the plant species that produce monoterpenoids are V. vinifera (grapes) and Humulus lupulus (hops) (King and Dickinson 2000).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites King and Dickinson 2000

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingcitation

    Aglycone moiety of precursor glucoside can be linked to β-D-glucose or specific disaccharides.

    “The aglycone moiety of the precursor glucoside can be linked to β-D-glucose or to the disaccharides 6-O-α-Larabinofuranosyl-β-D-glucopyranose, 6-O-α-L-rhamnopyranosyl-β-D-glucopyranose and 6-O-β-D-apiofuranosylβ-D-glucopyranose (Günata et al. 1985, Voirin et al. 1990).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Günata et al. 1985

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Voirin et al. 1990

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Findingcitation

    Muscat of Alexandria has bound:free ratio 5:1; some non-Muscat varieties 1:1.

    “Muscat of Alexandria grapes, for example, have a ratio of 5:1, whereas some non-Muscat varieties have a ratio of 1:1 (Williams et al. 1984).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Williams et al. 1984

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Findingcitation

    Enzymatic hydrolysis efficiently releases monoterpenes without modifying aromatic character.

    “However, enzymatic hydrolysis is an efficient method to release monoterpenes and it does not result in modification of the aromatic character (Günata et al. 1985).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Günata et al. 1985

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Findingcitation

    Large variations in ability of commercial wine yeast to convert 3MH to 3MHA were observed; in most cases this did not correspond to ability to release 4MMP.

    “Large variations in the ability of commercial wine yeast to convert 3MH were observed and in most cases this did not correspond to the ability to release 4MMP (Swiegers et al. 2005).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Swiegers et al. 2005

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Findingcitation

    Enzymatic hydrolysis two steps: first enzymes cleave 1,6-glycosidic linkage; second β-glucosidase liberates monoterpenols.

    “In the first step, an α-L-rhamnosidase and an α-L-arabinofuranosidase or a β-D-apiofuranosidase (depending on the structure of the aglycone moiety) cleave the 1,6-glycosidic linkage, and in the second step the monoterpenols are liberated from the monoterpenyl β-D-glucosides by the action of a β-glucosidase (Günata et al. 1988(Günata et al. , 1990)).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Günata et al. 1988

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Günata et al. 1990

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Findingcitation

    Non-megastigmane norisoprenoids are particularly active aroma compounds in wine; TDN is most important, has kerosene aroma.

    “Researchers have identified non-megastigmane norisoprenoids as particularly active aroma compounds in wine; the most important of these is 1,1,6-trimethyl-1,2-dihydronapthalene (TDN), which has a distinctive kerosene aroma (Winterhalter 1991).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Winterhalter 1991

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Findingcitation

    Phase III: citric acid metabolism with increase in acetic acid.

    “Phase III is characterised by the metabolism of citric acid accompanied by an increase in acetic acid.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Krieger et al. 2000

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Findingcitation

    AAB classified into genera; specific species associated with grapes/wine.

    “These bacteria are classified into the genera Acetobacter, Acidomonas, Gluconobacter and Gluconacetobacter; of these, Gluconobacter oxydans, Acetobacter aceti, Acetobacter pasteurianus, Gluconacetobacter liquefaciens and Gluconacetobacter hansenii are normally associated with grapes and wine (Drysdale and Fleet 1988).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Drysdale and Fleet 1988 source

  • May combine two claims.

    Findingcitation

    These bacteria can modify components and sensory properties of wine, providing opportunity to alter chemistry and possibly aroma/flavour.

    “Research in progress is showing that these bacteria can modify some of the components and sensory properties of wine, providing a new opportunity to alter the chemistry and possibly the aroma and flavour perception of wine (Figure 10) (Henick-Kling 1993, Bartowsky et al. 2002b, Matthews et al. 2004).”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites Henick-Kling 1993

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Bartowsky et al. 2002b

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Matthews et al. 2004

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Findingcitation

    Sorbic acid reduced to sorbyl alcohol, rearranges to 2,4-hexadien-1-ol, reacts with ethanol to 2-ethoxyhexa-3,5-diene.

    “Sorbic acid is reduced to sorbyl alcohol, which undergoes a chemical rearrangement at wine pH to 2,4-hexadien-1ol and can, in turn, react with ethanol to give rise to the ether 2-ethoxyhexa-3,5-diene (Crowell and Guymon 1975).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Crowell and Guymon 1975 source

  • May combine two claims.

    Findingcitation

    C13-norisoprenoids are secondary metabolites formed in grape berry; many accumulate as non-volatile glycosides.

    “C 13 -norisoprenoids are secondary metabolites formed in the grape berry and many accumulate as non-volatile glycosides (Winterhalter and Schreier 1994).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Winterhalter and Schreier 1994 source

  • May combine two claims.

    Findingcitation

    2-ethoxyhexa-3,5-diene has geranium leaf odour with threshold 100 ng/L.

    “The final compound has an odour reminiscent of geranium leaves with a reported sensory threshold of 100 ng/L (Riesen 1992).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Riesen 1992

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Findingcitation

    O. oeni is most well adapted wine-associated species and used almost exclusively for MLF in red, white, sparkling base wines.

    “Oenococcus oeni is the most well adapted wineassociated species and is used almost exclusively for the induction of malolactic fermentation (MLF) in red, white and sparkling base wines (Wibowo et al. 1985, Henick-Kling 1993, Henschke 1993).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Wibowo et al. 1985

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Henick-Kling 1993

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Henschke 1993

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Findingcitation

    Phase I: sugar catabolism with little acetic/lactic acid production; minimal citric/malic acid metabolized.

    “During the growth phase (Phase I), sugar catabolism occurs with little production of acetic and lactic acid; minimal citric and malic acid are metabolised in this phase.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Krieger et al. 2000

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Findingcitation

    Oxygen required for AAB metabolic activity/survival in wine is lower than previously thought; AAB can survive in barrels at low oxygen; spoilage of bottled red wine by AAB reported.

    “The concentration of oxygen required for metabolic activity and survival in wine is now much lower than previously thought; acetic acid bacteria can survive in wine barrels for long periods of low oxygen tension and, somewhat unexpect-edly, spoilage of bottled red wine by acetic acid bacteria has been reported (Drysdale andFleet 1988, Bartowsky et al. 2003).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Drysdale andFleet 1988

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Bartowsky et al. 2003 source

  • May combine two claims.

    Findingcitation

    Phase II: when cell numbers >5e6 cfu/mL, sugar catabolism ceases, malic acid metabolism proceeds with lactic acid production; citric acid untouched; no acetic acid during malic acid degradation.

    “As the bacterial cell numbers increase above 5 × 10 6 cfu/mL during Phase II, the cata-bolism of sugar ceases and malic acid metabolism proceeds accompanied by production of lactic acid; citric acid remains untouched at this stage, and there is no acetic acid produced during malic acid degradation.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Krieger et al. 2000

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Findingcitation

    Tartaric acid is relatively stable to bacterial activity; only aerobically metabolized by some Lactobacillus producing acetic, lactic, succinic acids.

    “Tartaric acid is relatively stable to bacterial activity and can only be metabolised aerobically by some Lactobacillus species with the production of acetic acid, lactic acid and succinic acid (Kandler 1983, Dittrich 1987).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Kandler 1983 source
    • cites Dittrich 1987

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Findingcitation

    Addition of citric acid to wine can increase diacetyl and also form other metabolites, particularly acetic acid.

    “Though the addition of citric acid to wine can be accompanied by an increase of diacetyl, the formation of other flavour metabolites, particularly acetic acid, can also result (Henick-Kling and Park 1994).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Henick-Kling and Park 1994 source

  • May combine two claims.

    Premisecitation

    Malolactic fermentation provides deacidification when needed and can enhance the flavour profile.

    “The malolactic fermentation, when needed, not only provides deacidification, but can enhance the flavour profile.”
    • Also stated in: § 1.3 Wine aroma and flavour · plain
      “Similarly, during the malolactic fermentation, bacteria do not only provide deacidification when needed but they can also enhance the flavour profile”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Henick-Kling 1993

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Henschke 1993

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Laurent et al. 1994

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisereasoning

    Saccharomyces cerevisiae is almost universally preferred for initiating alcoholic fermentation and is the main wine yeast.

    “For this reason, Saccharomyces cerevisiae is almost universally preferred for initiating alcoholic fermentation, and has earned itself the title of the wine yeast.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Wine aroma is due to volatile chemical compounds, and many grape-derived compounds are released and/or modified by flavour-active yeast and bacteria, with a further substantial portion of wine flavour substances resulting from the metabolic activities of these wine microbes.

    “The aroma of wine is due to chemical compounds with low boiling points, which are, therefore, volatile, escaping the glass and detectable by the human nose.”
    • Also stated in: § 1.3 Wine aroma and flavour · plain
      “However, while some volatile aroma compounds arise directly from chemical components of the grapes, many grape-derived compounds are released and/or modified by the action of flavour-active yeast and bacteria, and a further substantial portion of wine flavour substances result from the metabolic activities of these wine microbes”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites Schreier 1979

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Simpson 1979

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Williams et al. 1989

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    When nitrogen is adequate, α-ketoglutaric acid typically accumulates in wine to less than 50-100 mg/L, but when nitrogen is limited, several hundred mg/L can be produced by yeast.

    “When nitrogen is adequate, α-ketoglutaric acid typically accumulates in wine to less than 50-100 mg/L but, when nitrogen is limited, several hundred mg/L can be produced by yeast (Rankine 1968b, Radler 1993).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Rankine 1968b

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Radler 1993

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisereasoning

    Flavour-active yeasts and bacterial strains can produce desirable sensory results by helping to extract compounds from the solids in grape must, by modifying grape-derived molecules and by producing flavour-active metabolites.

    “Thus flavour-active yeasts and bacterial strains can produce desirable sensory results by helping to extract compounds from the solids in grape must, by modifying grape-derived molecules and by producing flavour-active metabolites.”
    • Also stated in: § 2. The modulation of wine flavour by yeast · plain
      “Flavour-active wine yeasts and malolactic bacteria can produce desirable sensory results by helping to extract compounds from the solids in grape must, by modifying grape-derived molecules and by producing flavour-active metabolites.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    Many grape-derived compounds are released and/or modified by flavour-active yeast and bacteria, and a further substantial portion of wine flavour substances result from the metabolic activities of these wine microbes.

    “However, while some volatile aroma compounds arise directly from chemical components of the grapes, many grape-derived compounds are released and/or modified by the action of flavour-active yeast and bacteria, and a further substantial portion of wine flavour substances result from the metabolic activities of these wine microbes”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites Schreier 1979

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Simpson 1979

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Williams et al. 1989

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

    Interpretationnone given

    Maloethanolic wine yeast would be favoured for low pH wines from cooler wine-producing regions, while malolactic wine yeast would provide the best solution for high pH wines from warmer regions.

    “Maloethanolic wine yeast would be favoured for low pH wines from the cooler wine-producing regions, while the malolactic wine yeast would provide the best solution for high pH wines from warmer regions.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Saccharomyces cerevisiae lacks an active malate transport system; malate enters wine yeast by simple diffusion, and its malic enzyme has about 15-fold lower substrate specificity than that of Schizosaccharomyces pombe, causing inefficient malate metabolism.

    “Unlike Schizosaccharomyces pombe, Saccharomyces cerevisiae lacks an active malate transport system; malate enters wine yeast by simple diffusion.”
    • Also stated in: § 2.1.1 Non-volatile acids · plain
      “the substrate specificity of the Saccharomyces cerevisiae malic enzyme is about 15-fold lower than that of the Schizosaccharomyces pombe malic enzyme (Radler 1993, Ansanay et al. 1996).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Radler 1993

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Ansanay et al. 1996

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Acetic acid becomes objectionable at concentrations of 0.7-1.1 g/L, depending on the style of wine; the optimal concentration is 0.2-0.7 g/L.

    “Acetic acid becomes objectionable at concentrations of 0.7-1.1 g/L, depending on the style of wine; the optimal concentration is 0.2-0.7 g/L (Corison et al. 1979, Dubois 1994).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Corison et al. 1979 source
    • cites Dubois 1994

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    The volatile acid content of wine is usually between 500 and 1000 mg/L (10-15% of total acid content), and acetic acid usually constitutes about 90% of the volatile acids.

    “The volatile acid content of wine is usually between 500 and 1000 mg/L (10-15% of the total acid content) and of this, acetic acid usually constitutes about 90% of the volatile acids (Fowles 1992, Henschke and Jiranek 1993, Radler 1993).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Fowles 1992 source
    • cites Henschke and Jiranek 1993

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Radler 1993

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    The production of succinic acid is common amongst yeasts and is the main carboxylic acid produced during fermentation, typically accumulating to 2 g/L.

    “The production of succinic acid is common amongst yeasts and is the main carboxylic acid produced during fermentation, where it typically accumulates to 2 g/L (Thoukis et al. 1965, Radler 1993, Coulter et al. 2004).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Thoukis et al. 1965

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Radler 1993

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Coulter et al. 2004

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Succinic acid production is highly variable amongst strains of Saccharomyces cerevisiae, but Saccharomyces uvarum or Saccharomyces bayanus strains tend to produce higher concentrations.

    “Its production is highly variable amongst strains of Saccharomyces cerevisiae but Saccharomyces uvarum or Saccharomyces bayanus strains tend to produce higher concentrations (Heerde and Radler 1978, Giudici et al. 1995, Eglinton et al. 2000).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Heerde and Radler 1978

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Giudici et al. 1995 source
    • cites Eglinton et al. 2000 source

  • May combine two claims.

    Premisecitation

    Wine strains of Saccharomyces cerevisiae typically degrade 3-45% of malic acid during fermentation, whereas most strains of Schizosaccharomyces pombe and Schizosaccharomyces malidevorans can completely degrade it to ethanol and CO2.

    “Whereas wine strains of Saccharomyces cerevisiae typically degrade 3-45% of malic acid during fermentation most strains of Schizosaccharomyces pombe and Schizosaccharomyces malidevorans can completely degrade it to ethanol and CO 2 (Rankine andFornachon 1964, Radler 1993).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Rankine andFornachon 1964

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Radler 1993

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    The Lactobacillus casei lacticodehydrogenase gene, expressed under control of the yeast alcohol dehydrogenase gene, converted 20% of the glucose into lactic acid, and this construct was introduced into eight wine yeast strains.

    “Encouraged by the fact that the Lactobacillus casei lacticodehydrogenase gene, expressed under control of the yeast alcohol dehydrogenase gene, converted 20% of the glucose into lactic acid, this construct was also introduced into eight wine yeast strains (Dequin et al. 1999).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Dequin et al. 1999 source

  • May combine two claims.

    Premisecitation

    Strain is the most important factor in determining keto acid production, but nitrogen type and content of the medium also affects the concentration of α-ketoglutaric acid produced.

    “Strain is the most important factor in determining keto acid production, but nitrogen type and content of the medium also affects the concentration of α-ketoglutaric acid produced (Rankine 1968 b).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Rankine 1968b

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Wines obtained with engineered lactic acid-alcoholic fermentation yeasts were effectively acidified, although the fermentation rate was slower.

    “Although the fermentation rate was slower, wines obtained with these engineered lactic acid-alcoholic fermentation yeasts were effectively acidified.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Dequin et al. 1999 source

  • May combine two claims.

    Premisecitation

    Excessive ethanol can produce a perceived 'hotness' and mask the overall aroma and flavour of the wine.

    “Excessive ethanol, however, can produce a perceived 'hotness' and mask the overall aroma and flavour of the wine (Guth and Sies 2002).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Guth and Sies 2002

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    This step is crucial for maintaining a redox balance in the cell, as it reoxidises NADH to NAD+, which is required for glycolysis.

    “This step is crucial for maintaining a redox balance in the cell, as it reoxidises NADH to NAD + , which is required for glycolysis (Pronk et al. 1996).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Pronk et al. 1996

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Acetaldehyde is converted to ethanol through alcohol dehydrogenase enzymes, the main one being encoded by the ADH1 gene.

    “Acetaldehyde is then converted to ethanol through alcohol dehydrogenase enzymes, the main one being encoded by the ADH1 gene.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Pronk et al. 1996

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    BAT1 is highly expressed during logarithmic growth phase and down-regulated during stationary phase, while BAT2 shows an inverse pattern of expression.

    “the BAT1 gene is highly expressed during the logarithmic growth phase and down-regulated during the stationary phase, while the BAT2 gene shows an inverse pattern of expression (Eden et al. 1996).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Eden et al. 1996 source

  • May combine two claims.

    Premisecitation

    Overexpression of BAT1 increased the concentration of isoamyl alcohol and its corresponding ester isoamyl acetate but to a lesser extent; isobutanol and isobutyric acid also increased.

    “wines and distillates prepared by strains overexpressing BAT1 increased the concentration of isoamyl alcohol and its corresponding ester isoamyl acetate but to a lesser extent.The concentration of the higher alcohol isobutanol and isobutyric acid also increased.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Lilly 2004

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Acetaldehyde is the major carbonyl compound found in wine with concentrations ranging from 10 mg/L to 75 mg/L and a sensory threshold value of 100 mg/L.

    “Acetaldehyde is the major carbonyl compound found in wine with concentrations ranging from 10 mg/L to 75 mg/L and a sensory threshold value of 100 mg/L (Schreier 1979, Berg et al. 1955) (Table 1).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Schreier 1979

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Berg et al. 1955

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Previous studies showed that temperature does not affect aldehyde concentration at all.

    “However, in previous studies it was shown that temperature does not affect aldehyde concentration at all (Amerine and Ough 1980).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Amerine and Ough 1980

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Excessive concentrations of higher alcohols can result in a strong, pungent smell and taste, whereas optimal levels impart fruity characters.

    “Excessive concentrations of higher alcohols can result in a strong, pungent smell and taste, whereas optimal levels impart fruity characters (Table 1) (Nykänen et al. 1977, Lambrechts and Pretorius 2000, Swiegers and Pretorius 2005).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Nykänen et al. 1977

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Lambrechts and Pretorius 2000 source

      Checked before — its earlier verdict is held back until a new check runs.

    • cites Swiegers and Pretorius 2005

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Concentrations of higher alcohols below 300 mg/L add a desirable level of complexity to wine, whereas concentrations exceeding 400 mg/L can have a detrimental effect.

    “It has been reported that concentrations below 300 mg/L add a desirable level of complexity to wine, whereas concentrations that exceed 400 mg/L can have a detrimental effect (Rapp and Versini 1991).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Rapp and Versini 1991

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Ethanol concentration, fermentation temperature, pH and composition of grape must, aeration, level of solids, grape variety, maturity and skin contact time affect the concentration of higher alcohols in the final product.

    “Furthermore, ethanol concentration, fermentation temperature, the pH and composition of grape must, aeration, level of solids, grape variety, maturity and skin contact time also affect the concentration of higher alcohols in the final product (Fleet and Heard 1993).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Fleet and Heard 1993

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Pyruvate, the end-product of glycolysis, is converted to acetaldehyde through pyruvate decarboxylase enzymes encoded by three genes, PDC1-3.

    “Pyruvate, the end-product of glycolysis, is converted to acetaldehyde through pyruvate decarboxylase enzymes encoded by three genes, PDC1-3 (Pronk et al. 1996).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Pronk et al. 1996

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Glycerol is a major product of alcoholic fermentation.

    “Glycerol is a major product of alcoholic fermentation (Gancedo et al. 1968, Pronk et al. 1996, Scanes et al. 1998).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Gancedo et al. 1968 source
    • cites Pronk et al. 1996

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Scanes et al. 1998

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    No relationship exists between glycerol concentration and the tears that sometimes form on the inside of a wine glass.

    “Furthermore, no relationship exists between glycerol concentration and the tears that sometimes form on the inside of a wine glass.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Noble and Bursick 1984

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Overexpression of BAT2 resulted in a substantial increase in the concentration of isobutanol, isobutyric acid and propionic acid production, while deletion of this gene led to a decrease in production of these compounds.

    “The overexpression of the BAT2 gene resulted in a substantial increase in the concentration of isobutanol, isobutyric acid and propionic acid production, while the deletion of this gene led to a decrease in the production of these compounds.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Lilly 2004

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Although yeasts biosynthesise some diacetyl (0.2-0.3 mg/L) in wine, most of it originates from the metabolic activities of lactic acid bacteria.

    “Although yeasts biosynthesise some diacetyl (0.2-0.3 mg/L) in wine, most of it originates from the metabolic activities of lactic acid bacteria, as discussed later (Laurent et al. 1991, Bartowsky andHenschke 2004).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Laurent et al. 1991

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Bartowsky andHenschke 2004

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Tannins inhibit the cinnamate decarboxylase enzyme of Saccharomyces cerevisiae, which might be a factor in red wines where tannins are abundant.

    “Tannins do, however, inhibit the cinnamate decarboxylase enzyme of Saccharomyces cerevisiae, which might be a factor in red wines where tannins are abundant (Chatonnet et al. 1993).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Chatonnet et al. 1993 source

  • May combine two claims.

    Premisecitation

    Although many factors have been reported to affect hydrogen sulfide production, including yeast strain, sulfur source, nitrogen composition and nitrogen concentration of the test medium, the strain of yeast is the key to determining hydrogen sulfide production; surveys show that strains vary widely in their ability to produce hydrogen sulfide.

    “Although many factors have been reported to affect hydrogen sulfide production, including yeast strain, sulfur source, nitrogen composition and nitrogen concentration of the test medium, the strain of yeast is the key to determining hydrogen sulfide production; surveys show that strains vary widely in their ability to produce hydrogen sulfide (Zambonelli 1964, Rankine 1968, Eschenbruch et al. 1978”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Zambonelli 1964

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Rankine 1968

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Eschenbruch et al. 1978

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Sulfur-containing flavour compounds typically occur in wine at very low concentrations, have very low detection thresholds and generally confer a negative sensory contribution to wine.

    “Sulfur-containing flavour compounds typically occur in wine at very low concentrations, have very low detection thresholds and generally confer a negative sensory contribution to wine (Table 2) (Peppard 1988, Mestres et al. 2000, Vermeulen et al. 2005).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Peppard 1988

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Mestres et al. 2000 source
    • cites Vermeulen et al. 2005 source

  • May combine two claims.

    Premisecitation

    In white wine ferments, hydrogen sulfide formation is inversely correlated with initial total nitrogen, and glutathione measured after fermentation.

    “In white wine ferments, hydrogen sulfide formation is inversely correlated with initial total nitrogen, and glutathione measured after fermentation (Park et al. 2000).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Park et al. 2000

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Although volatile phenols can contribute positively to the aroma of some wines, they are better known for their contribution to off-flavours such as 'Band-aid', 'barnyard' or 'stable', which results from high concentrations of ethylphenols.

    “Although volatile phenols can contribute positively to the aroma of some wines, they are better known for their contribution to off-flavours such 'Band-aid', 'barnyard' or 'stable', which results from high concentrations of ethylphenols (Dubois 1983).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Dubois 1983

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    At low concentrations diacetyl can be described as nutty or toasty, but it becomes objectionable at concentrations between 1 and 4 mg/L.

    “At low concentrations it can be described as nutty or toasty, but it becomes objectionable at concentrations between 1 and 4 mg/L (Sponholz, 1993).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Sponholz, 1993

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Although Riesling wines contained similar esters, 3-methyl butanoate and ethyl hexanoate were found to be unimportant to the final aroma of the wines.

    “Although, Riesling wines contained similar esters, 3-methyl butanoate and ethyl hexanoate were found to be unimportant to the final aroma of the wines (Smyth et al. 2005).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Smyth et al. 2005

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Interpretationreasoning

    Under nitrogen limitation, the SRS pathway is activated and sulfide accumulates due to lack of precursors.

    “Therefore, the SRS pathway will be activated and sulfide will accumulate due to the lack of precursors.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationreasoning

    Disulfides left as by-products cannot be removed by copper ions, so not all off-flavours can be removed by copper fining.

    “However, the disulfides left as by-products of the reaction cannot be removed by copper ions, and not all of the off-flavours can, therefore, be removed in this way.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationcitation

    Furfurylthiol production is linked to HS- anion production, which is not produced when sufficient ammonium sulfate is added.

    “Therefore, production of furfurylthiol is linked to the production of the HS -anion, which is not produced when ammonium sulfate is added in sufficient quantities in a fermentation (Blanchard et al. 2001).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Blanchard et al. 2001 source

  • May combine two claims.

    Interpretationcitation

    In another strain, MET17 overexpression did not reduce hydrogen sulfide formation, indicating O-acetylserine/O-acetylhomoserine sulfhydrylase activity is not directly related to hydrogen sulfide formation.

    “However, this was not the case with another strain, indicating that O-acetylserine/O-acetylhomoserine sulfhydrylase activity is not directly related to hydrogen sulfide formation (Spiropoulos and Bisson 2000).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Spiropoulos and Bisson 2000 source

  • May combine two claims.

    Interpretationcitation

    Four genes influence 4MMP release in a laboratory strain, indicating the mechanism probably involves multiple genes.

    “Four genes that influence the release of the volatile thiol 4MMP in a laboratory strain were identified, indicating that the mechanism of release probably involves multiple genes.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    Cysteine and methionine concentrations in grape juices are typically insufficient to meet metabolic needs of growing cells, so the SRS metabolic pathway is induced.

    “Because the concentrations of the amino acids cysteine and methionine in grape juices are typically not sufficient to meet the metabolic needs of growing cells, the SRS metabolic pathway is induced in order to meet this demand (Henschke and Jiranek 1993).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Henschke and Jiranek 1993

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    In Saccharomyces cerevisiae, hydrogen sulfide is the product of the Sulfate Reduction Sequence (SRS) pathway and acts as an intermediate in the biosynthesis of sulfur-containing amino acids.

    “In Saccharomyces cerevisiae, hydrogen sulfide is the product of the Sulfate Reduction Sequence (SRS) pathway and acts as an intermediate in the biosynthesis of sulfurcontaining amino acids (Yamagata 1989, Rauhut 1993, Thomas and Surdin-Kerjan 1997).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Yamagata 1989 source
    • cites Rauhut 1993

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Thomas and Surdin-Kerjan 1997 source

  • May combine two claims.

    Premisecitation

    Hydrogen sulfide is highly reactive and can react to generate compounds that impact wine flavour.

    “Hydrogen sulfide is a highly reactive species, which can take part in a range of reactions to generate compounds that impact on the flavour of a wine (Vermeulen et al. 2005).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Vermeulen et al. 2005 source

  • May combine two claims.

    Interpretationcitation

    Alternative monoterpene biosynthesis pathway is located in mitochondrion and involves conversion of leucine to mevalonic acid.

    “This alternative pathway, which is located in the mitochondrion, involves the conversion of leucine to mevalonic acid.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Carrau et al. 2005 source

  • May combine two claims.

    Interpretationcitation

    Some strains of Saccharomyces yeast could contribute to floral aroma of wine by de novo synthesis of monoterpenes, augmented by higher assimilable nitrogen and microaerobic fermentation.

    “This work suggests that some strains of Saccharomyces yeast could contribute to the floral aroma of wine by de novo synthesis of monoterpenes, and this contribution could be augmented by certain fermentation conditions such as musts with higher concentrations of assimilable nitrogen like the ammonium ion, in combination with microaerobic fermentation (Carrau et al. 2005).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Carrau et al. 2005 source

  • May combine two claims.

    Interpretationreasoning

    Huge untapped flavour potential remains in wine after fermentation, not fully utilised due to metabolic limitations of yeast.

    “It is, therefore, clear that there is a huge, untapped flavour potential remaining in the wine after fermentation but that this source of flavour is not fully utilised due to the metabolic limitations of the yeast cell.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    Metabolism of glycerol is not widespread amongst the wine lactic acid bacteria (Lactobacillus brevis, Lactobacillus hilgardii and Pediococcus pentosaceus) and results in wine spoilage.

    “Metabolism of glycerol is not widespread amongst the wine lactic acid bacteria (Lactobacillus brevis, Lactobacillus hilgardii and Pediococcus pentosaceus) and results in wine spoilage (Sponholz 1993, Claisse and Lonvaud-Funel 2001, Vizoso Pinto et al. 2004).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Sponholz 1993

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Claisse and Lonvaud-Funel 2001 source
    • cites Vizoso Pinto et al. 2004

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • Rests on an assumption: Glycerol can be degraded by two pathways, either via glycerol dehydrase or glycerol kinase.
    • Rests on an assumption: The glycerol dehydrase converts glycerol to 3-hydroxypropionaldehyde.
    • Rests on an assumption: Spontaneous chemical dehydration of the aldehyde, by heating or by long-term storage in acidic solution, results in the formation of acrolein, which reacts with wine phenolics, particularly in red wines, to form a bitter complex.

  • May combine two claims.

    Premisecitation

    Oenococcus oeni uses the heterolactic fermentation pathway during growth on fructose as a substrate and the mannitol pathway when using fructose as an electron acceptor.

    “That is, Oenococcus oeni uses the heterolactic fermentation pathway during growth on fructose as a substrate and the mannitol pathway when using fructose as an electron acceptor (Richter et al. 2003) (Figure 10).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Richter et al. 2003

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisenone given

    Bacteria can modulate the concentrations of alcohols such as glycerol, mannitol and erythritol, and affect wine flavour.

    “Bacteria can modulate the concentrations of alcohols such as glycerol, mannitol and erythritol, and affect wine flavour.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisenone given

    In heterofermentative lactic acid bacteria, the reduction of fructose is a mechanism by which the cell can regenerate NAD+, particularly under anaerobic conditions.

    “In heterofermentative lactic acid bacteria, the reduction of fructose is a mechanism by which the cell can regenerate NAD + , particularly under anaerobic conditions.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    The shift from one fermentation type to the other is related to the growth rate, or to the high metabolic rates present during high growth rates.

    “The shift is related to the growth rate, or to the high metabolic rates present during high growth rates (Richter et al. 2003).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Richter et al. 2003

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    In Oenococcus oeni fructose can be metabolised by two different pathways: heterolactic fermentation or mixed heterolactic/mannitol fermentation.

    “In Oenococcus oeni fructose can be metabolised by two different pathways: heterolactic fermentation or mixed heterolactic/mannitol fermentation (Richter et al. 2003).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Richter et al. 2003

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Norisoprenoids divided into megastigmane and non-megastigmane.

    “Structurally, norisoprenoids can be divided into two main groups, megastigmane and non-megastigmane (Ribéreau-Gayon et al. 2000b).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Ribéreau-Gayon et al. 2000b

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

    Premisenone given

    Acetaldehyde and diacetyl are two of the more important flavour-active carbonyls in wine and both can be metabolised by wine bacteria.

    “Acetaldehyde and diacetyl are two of the more important flavour-active carbonyls in wine and both can be metabolised by wine bacteria.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisenone given

    The homofermentative lactic acid bacteria are also able to utilise mannitol, transporting it into the cell via the mannitol-specific phosphotransferase system and phosphorylating it to mannitol 1-phosphate, which is then oxidised by mannitol 1-phosphate dehydrogenase to the glycolysis intermediate fructose 6-phosphate.

    “The homofermentative lactic acid bacteria are also able to utilise mannitol, transporting it into the cell via the mannitol-specific phosphotransferase system and phosphorylating it to mannitol 1-phosphate, which is then oxidised by mannitol 1-phosphate dehydrogenase to the glycolysisintermediate fructose 6-phosphate (Figure 10).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Heterolactic fermentation is carried out by bacteria in the late-exponential growth phase, whereas mixed heterolactic/mannitol fermentation is common during exponential growth.

    “Heterolactic fermentation is carried out by bacteria in the late-exponential growth phase, whereas mixed heterolactic/mannitol fermentation is common during exponential growth.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    The sensory perception of diacetyl in wine is highly dependent upon the presence of other compounds in the wine, and is influenced by the age, the style and origin of the wine.

    “The sensory perception of diacetyl in wine is also highly dependent upon the presence of other compounds in the wine, and is influenced by the age, the style and origin of the wine (Rankine et al. 1969, Martineau et al. 1995, Bartowsky et al. 2003).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Rankine et al. 1969

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Martineau et al. 1995 source

      Checked before — its earlier verdict is held back until a new check runs.

    • cites Bartowsky et al. 2003 source

  • May combine two claims.

    Premisecitation

    The presence of phenol carboxylic acids (caffeic, ferulic, p-coumaric and gallic acids) and catechin appear to stimulate the growth of Oenococcus oeni, particularly by reducing the initial lag phase and enhancing the metabolism of citric acid.

    “The presence of phenol carboxylic acids (caffeic, ferulic, p-coumaric and gallic acids) and catechin appear to stimulate the growth of Oenococcus oeni, particularly by reducing the initial lag phase and enhancing the metabolism of citric acid (Vivas et al. 1997, Rozes et al. 2003).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Vivas et al. 1997

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Rozes et al. 2003

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    When present at a high concentration (exceeding 5-7 mg/L) in wine, diacetyl is regarded by many to be undesirable.

    “When present at a high concentration (exceeding 5-7 mg/L) in wine, diacetyl is regarded by many to be undesirable (Rankine et al. 1969, Davis et al. 1985).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Rankine et al. 1969

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Davis et al. 1985 source

  • May combine two claims.

    Premisecitation

    In white wine, which only contains a low concentration of flavanols, only the vinylphenol was produced as the major product, and at much diminished concentration compared to that produced by the reference Brettanomyces bruxellensis strain.

    “However, in white wine, which only contains a low concentration of flavanols, only the vinylphenol was produced as the major product, and at much diminished concentration compared to that produced by the reference Brettanomyces bruxellensis strain (Chatonnet et al. 1997).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Chatonnet et al. 1997 source

  • May combine two claims.

    Premisecitation

    Malolactic fermentation conducted at lower temperatures, perhaps 18oC rather than 25oC, tends to be slower, but wines accumulate a higher concentration of diacetyl.

    “Malolactic fermentation conducted at lower temperatures, perhaps 18ºC rather than 25ºC, tends to be slower, but wines accumulate a higher concentration of diacetyl (Lonvaud-Funel et al. 1984, Hart 1997).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Lonvaud-Funel et al. 1984

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Hart 1997

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    The sulfur-containing amino acid cysteine and the tri-peptide glutathione stimulated the growth of Oenococcus oeni whereas methionine did not.

    “The sulfur-containing amino acid cysteine and the tri-peptide glutathione stimulated the growth of Oenococcus oeni whereas methionine did not (Rauhut et al. 2004).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Rauhut et al. 2004

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisenone given

    The decomposition rate of cysteine in the presence of diacetyl at pH 3.5 and 25oC is approximately 70% over seven days whereas at pH 8.0, cysteine is completely decomposed within an hour-and-a-half.

    “It has been found that the decomposition rate of cysteine in the presence of diacetyl at pH 3.5 and 25ºC is approximately 70% over seven days whereas at pH 8.0, cysteine is completely decomposed within an hour-and-ahalf.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    In the presence of sulfur dioxide, the concentration of free diacetyl in wine is lowered, however as the sulfur dioxide content decreases, as for example during ageing, the ratio of free diacetyl will increase again, thus increasing its sensory impact.

    “In the presence of sulfur dioxide, the concentration of free diacetyl in wine is lowered, however as the sulfur dioxide content decreases, as for example during ageing, the ratio of free diacetyl will increase again, thus increasing its sensory impact (Nielsen and Richelieu 1999).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Nielsen and Richelieu 1999

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Phenolic acids can be transported into bacterial cells by active transport, decarboxylated to the vinyl derivatives by hydroxycinnamic acid decarboxylases and enzymatically reduced to the ethyl derivatives.

    “Phenolic acids can be transported into bacterial cells by active transport, decarboxylated to the vinyl derivatives by hydroxycinnamic acid decarboxylases and enzymatically reduced to the ethyl derivatives (Cavin et al. 1993(Cavin et al. , 1994) ) (Figure 10).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Cavin et al. 1993 source
    • cites Cavin et al. 1994

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Researchers observed increases in ethyl ester concentration in wine following malolactic fermentation, including ethyl acetate, ethyl hexanoate, ethyl lactate, and ethyl octanoate, as well as decreases in some esters.

    “Researchers observed increases in ethyl ester concentration in wine following malolactic fermentation, including ethyl acetate, ethyl hexanoate, ethyl lactate, and ethyl octanoate, as well as decreases in some esters (Zeeman et al. 1982, Dittrich 1987, Laurent et al. 1994, de Revel et al. 1999, Delaquis et al. 2000, Gambaro et al. 2001).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Zeeman et al. 1982

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Dittrich 1987

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Laurent et al. 1994

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Studies in a synthetic wine-like medium have shown that hydroxycinnamic acids inhibit the growth of Oenococcus oeni more than do hydroxybenzoic acids, whereas Lactobacillus hilgardii is less affected by these phenolic compounds, with the exception of p-coumaric acid.

    “Studies in a synthetic wine-like medium have shown that hydroxycinnamic acids inhibit the growth of Oenococcus oeni more than do hydroxybenzoic acids, whereas Lactobacillus hilgardii is less affected by these phenolic compounds, with the exception of p-coumaric acid (Campos et al. 2003).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Campos et al. 2003 source

  • May combine two claims.

    Premisenone given

    Bacteria can produce significant amounts of diacetyl during malolactic fermentation, and diacetyl is one of the most important flavour compounds produced by Oenococcus oeni.

    “In contrast, bacteria can produce significant amounts of diacetyl during malolactic fermentation, and diacetyl is one of the most important flavour compounds produced by Oenococcus oeni.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Oenococcus oeni strains possess various glycosidase activities; however, these activities on synthetic glycosides were dependent on wine conditions such as pH, ethanol and residual sugar content.

    “Oenococcus oeni strains possess various glycosidase activities; however, these activities on synthetic glycosides were dependent on wine conditions such as pH, ethanol and residual sugar content (Grimaldi et al. 2000).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Grimaldi et al. 2000 source

  • May combine two claims.

    Premisecitation

    The choice of yeast and bacterial strain to modulate wine flavour according to specifications of a target market will differ with (i) the type and style of wine to be made; (ii) the grape variety and viticultural practices; as well as (iii) winemaking techniques and technical requirements of the winery.

    “The choice of yeast and bacterial strain to modulate wine flavour according to specifications of a target market will differ with (i) the type and style of wine to be made; (ii) the grape variety and viticultural practices; as well as (iii) winemaking techniques and technical requirements of the winery (reviewed in Pretorius 2000, 2003, 2004, de Barros Lopes et al. 2005, Pretorius et al. 2005, Swi”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites Pretorius 2000

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Pretorius 2003

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Pretorius 2004

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisenone given

    Oenococcus oeni is a fastidious organism that requires several amino acids and short peptides for growth.

    “Oenococcus oeni is a fastidious organism that requires several amino acids and short peptides for growth.”
    Quote in the paperNot a substantial claim
117 of 117

  • The paper relies on this without support.

    The choice of microorganism to conduct fermentation is a tool that can produce wines with specific flavour profiles.

    “One of these tools is the choice of microorganism to conduct fermentation.”

  • The paper relies on this without support.

    Yeasts are predominant during the complex process of winemaking.

    “Yeasts are predominant during the complex process of winemaking.”

  • The paper relies on this without support.

    Glycerol can be degraded by two pathways, either via glycerol dehydrase or glycerol kinase.

    “Glycerol can be degraded by two pathways, either via glycerol dehydrase or glycerol kinase.”

  • The paper relies on this without support.

    The glycerol dehydrase converts glycerol to 3-hydroxypropionaldehyde.

    “The glycerol dehydrase converts glycerol to 3hydroxypropionaldehyde.”

  • The paper relies on this without support.

    Spontaneous chemical dehydration of the aldehyde, by heating or by long-term storage in acidic solution, results in the formation of acrolein, which reacts with wine phenolics, particularly in red wines, to form a bitter complex.

    “Spontaneous chemical dehydration of the aldehyde, by heating or by long-term storage in acidic solution, results in the formation of acrolein, which reacts with wine phenolics, particularly in red wines, to form a bitter complex (Figure 10).”

  • The paper relies on this without support.

    Wine flavour is one of the key drivers of consumer choice.

    “Nevertheless, it is a common fact that wine flavour is one of the key drivers of consumer choice.”
6 of 6

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • The stated products of two phenolic acids are reversed

    Minor

    One passage assigns 4-vinylguaiacol to p-coumaric acid and 4-vinylphenol to ferulic acid. A later passage assigns the products in the opposite order.

  • The same diacetyl range is described as objectionable and desirable

    Minor

    One section calls diacetyl objectionable at 1-4 mg/L, while another says that approximately the same range can provide a desirable flavour. The latter qualifies this by wine style, but the earlier claim does not.

  • Red-wine glycerol claim reverses the listed values

    Minor

    The stated comparison puts red wine first and white wine second, but the listed values put red wine lower, not higher.

  • A mousy compound has two different abbreviations

    Minor

    Table 1 labels 2-acetyltetrahydropyridine ACPTY, whereas the discussion labels the same compound ACTPY.

  • Dimethyl sulfide range includes concentrations below its threshold

    Minor

    The text says wine concentrations are well above the sensory thresholds, but Table 2 gives a range starting at 1.4 μg/L-below both the stated white- and red-wine thresholds.

5 of 5

Cites

Flagged first, then by citations

Research works printed but not linked: 21

  1. Amerine M.A., 1980, Methods for Wine and Must Analysis, 74
  2. B. Bach, C. Camarasa, T. Rossignol, B. Blondin, and S. Dequin (2004 ) ?Aminobutyrate assimilation in Saccharomyces cerevisiae during wine fermentation . Proceedings of Physiology of Yeasts and Filamentous Fungi (PYFF2), Anglet, France. p.185 (abstract).
  3. Bartowsky E., 2002, The Australian Grapegrower and Winemaker, 461, 7
  4. Bartowsky E.J., 2004, Australian and New Zealand Grapegrower and Winemaker, 490, 83
  5. Baumes R., 1988, Connaissance de la Vigne et du Vin, 22, 209
  6. Bayonove C.L., 1984, Bulletin de l'OIV, 643, 741
  7. Berg H., 1955, Food Technology, 9, 23
  8. J.F. Cavin, J. Guzzo, L. Gasporotto, E. Logier, and C. Divies (1994 ) Etude de la decarboxylation de l'acide para-coumarique chez Lactobacillus plantarum . Proceedings of the SFM Congress: Gestion des Populations Microbiennes dans les Industries Agro-Alimentaires, Dijon, Francep.36 .
  9. Coulter A.D., 2004, Australian and New Zealand Wine Industry Journal, 19, 16
  10. R.E. Day, M. Gishen, P.W. Godden, and J.B. Hughes (2002 ) Producing unique wine styles for overseas markets . Proceedings of the Eleventh Australian Wine Industry Technical Conference (Australian Wine Industry Technical Conference Inc.: Adelaide, SA) pp.27 -32 .
  11. Barros Lopes M.A., 2003, Australian and New Zealand Wine Industry Journal, 18, 17
  12. Barros Lopes M.A., 2005, Handbook of Food Science, Technology and Engineering; Volume 1 - Properties and Products, 40
  13. Dittrich H.H., 1987, Mikrobiologie des Weines. Handbuch der Lebensmitteltechnologie
  14. Dubois P., 1983, Flavour of Distilled Beverages, Origins and Developments, 110
  15. Eglinton J., 2003, Wine Industry Journal, 18, 16
  16. Eschenbruch R., 1978, Vitis, 17, 67
  17. Etievant P.X., 1991, Volatile Compounds of Food and Beverages, 483
  18. Fagan G.L., 1981, Vitis, 20, 36
  19. 10.1002/(SICI)1097-0061(19960315)12:3<247::AID-YEA911>3.0.CO;2-I · DOI
  20. Forrestal P., 2000, The Global Encyclopedia of Wine
  21. I.L. Francis, P.B. Hoj, R.G. Dambergs, M. Gishen, M.A. Barros Lopes, I.S. Pretorius, P.W. Godden, P.A Henschke, M.J. Herderich, and E.J. Waters (2005 ) Objective measures of grape quality - are they achieveable? Proceedings of the Twelfth Australian Wine Industry Technical Conference, Melbourne, Australia (Australian Wine Industry Technical Conference Inc.: Adelaide, SA) pp.85 -89 .

Cited by

Sorted by citations

Related

Authors
SWIEGERS, J. H., BARTOWSKY, E. J., HENSCHKE, P. A., & PRETORIUS, I. S.
Affiliations
Australian Wine Research Institute (AU)
Corresponding author
PRETORIUS, I.S.
ORCID
Venue
Australian Journal of Grape and Wine Research
Publisher
Wiley
Published
2005-07
Volume
11
Issue
2
Pages
139-173
ISSN
  • 1322-7130 (ISSN-L)
  • 1755-0238
DOI
10.1111/j.1755-0238.2005.tb00285.x
OpenAlex
W1998869177
Cited by
1,216
References
98
Citations by year
2026: 68 · 2025: 65 · 2024: 56 · 2023: 72 · 2022: 76 · 2021: 91 · 2020: 86 · 2019: 82 · 2018: 72 · 2017: 73 · 2016: 75 · 2015: 56 · 2014: 60 · 2013: 51 · 2012: 59
FWCI
28.47
Type
journal article
Language
en
Open access
Licence
doi.wiley.com/10.1002/tdm_license_1.1 (tdm, 3714 d)
Locations
  • Australian Journal of Grape and Wine Research (publishedVersion)
  • Adelaide Research & Scholarship (AR&S) (University of Adelaide) (submittedVersion)
Funders
  • Alberta Water Research Institute
  • Australian Government
Topics
  • Life Sciences › Agricultural and Biological Sciences › Food Science › Fermentation and Sensory Analysis
  • Life Sciences › Agricultural and Biological Sciences › Plant Science › Horticultural and Viticultural Research
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Biotechnology › Biochemical and biochemical processes
Keywords
wine aroma, wine flavor, Saccharomyces cerevisiae, Oenococcus oeni, malolactic fermentation, alcoholic fermentation, volatile metabolites, higher alcohols, esters, sulfur compounds, volatile fatty acids, microbial metabolism, sensory profile

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-10.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-10.

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Statistics and arithmetic are recomputed, not judged.

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