Three flavor-active volatile thiols (4-mercapto-4-methylpentan-2-one, 4-mercapto-4-methylpentan-2-ol and 3-mercaptohexan-1-ol) involved in Vitis vinifera L. var. Sauvignon blanc wine aroma can be generated vitro from nonvolatile must extracts by the enzyme action of a cell-free extract obtained gastrointestinal bacterium Eubacterium limosum. The specificity cysteine conjugate β-lyase (EC 4.4.1.13) which is contained extract, strongly suggested existence precursor for these having structure...

Five volatile thiols previously identified in Sauvignon blanc wines, 4-mercapto-4-methylpentan-2-one (4MMP), 4-mercapto-4-methylpentan-2-ol (4MMPOH), 3-mercapto-3-methylbutan-1-ol (3MMB), 3-mercaptohexan-1-ol (3MH) and 3-mercaptohexyl acetate (A3MH) were found to be present wines made from several other white <i>Vitis vinifera</i> grape varieties. An assay of these showed that concentrations 4MMP, 3MH, A3MH considerably higher than the perception thresholds certain Gewürztraminer, Riesling,...

Background The digestion of dietary starch in humans is initiated by salivary α-amylase, an endo-enzyme that hydrolyzes into maltose, maltotriose and larger oligosaccharides. Salivary amylase accounts for 40 to 50% protein human saliva rapidly alters the physical properties starch. Importantly, quantity enzymatic activity show significant individual variation. However, linking variation levels with oral perception has proven difficult. Furthermore, relationship between copy number variations...

Abstract S ‐Cysteine conjugate precursors of three volatile thiols were monitored in Vitis vinifera L cv Sauvignon blanc grapes during fruit ripening to assess the influence vine water and nitrogen status on grape aroma potential field conditions. Four dry farmed plots studied Pessac‐Léognan Graves appellations (Bordeaux area) 1998, which was a very vintage, 1999, when regular summer rainfall occurred. Soil water‐holding capacity ranged from low high. total content related soil organic...

The development of the aromas certain grapes varieties during fermentation has not been greatly investigated in enology until now. Recent works on sulfur compounds that participate aroma Sauvignon blanc wines offer an example grape flavor enhancement by yeasts. Several very odorous volatile thiols have identified as constituents particular wines: 4-mercapto-4-methylpentan-2-one (4MMP), 4-mercapto-4-methylpentan-2-ol, 3-mercaptohexanol, 3-mercaptohexyl acetate. These different are practically...

Oleocanthal, a major phenolic compound in extra-virgin olive oil with antiinflammatory properties, elicits an unusual oral pungency sensed almost exclusively the throat. This contrasts most other common irritants, such as cinnamaldehyde, capsaicin, and alcohol, which irritate mucus membranes throughout cavity. Here, we show that this rare irritation pattern is consequence of both specificity oleocanthal for single sensory receptor anatomical restriction to pharynx, within We demonstrate,...

When Sauvignon blanc or Gros Manseng grape must was percolated through an immobilized gamma-glutamyltranspeptidase column, there a significant increase in the concentration of S-3-(hexan-1-ol)-L-cysteine, precursor 3-mercaptohexan-1-ol, compound that contributes to varietal aroma wines made from these grapes. Low- and high-resolution liquid secondary ion mass sepectrometry (LSIMS) analyses established presence S-3-(hexan-1-ol)-glutathione must. The identification this suggests...

A method was developed for determining the amount of seed and skin proanthocyanidin extraction into wines by direct measurement. This based upon analysis cleavage products after acid catalysis in presence excess phloroglucinol. On basis extracts from grape tissues, two observations were made as follows: (i) extension subunit compositions considerably different each other, (ii) their composition did not vary with time. Thus, comparing proportional proanthocyanidins wine relative to...

The purpose of this study was to assess the relationship between astringency and tannin concentration in red wine using various analytical methods. Forty wines were selected from a large commercial producer based on preliminary assessment variation with selection intended reflect potential amount. Tannin determined previously published methods, including absorption light at 280 nm, reaction 4-dimethylaminocinnamaldehyde, protein precipitation, phloroglucinolysis, gel permeation...

The method presented for measuring the aromatic potential of Sauvignon blanc must is based on an assay S-cysteine conjugate precursors three volatile thiols involved in characteristic aroma wines made from this grape variety: 4-mercapto-4-methylpentan-2-one, 4-mercapto-4-methylpentan-2-ol, and 3-mercaptohexan-1-ol. These compounds were released enzymatically their by percolating through immobilized tryptophanase column (EC 4.1.99.1), catalyzing α,β-elimination reaction conjugate. analyzed...

The localization in the berry of S-cysteine conjugates, sulfur flavor precursors Sauvignon blanc grapes, was studied. assay conjugates showed that content 4-mercapto-4-methylpentan-2-one and 4-mercapto-4-methylpentan-2-ol (P-4MMP P-4MMPOH) were equivalent juice skin, while concentration 3-mercaptohexan-1-ol precursor (P-3MH) almost eight times higher skin. In comparison with immediate pressing, skin contact only allowed a modest increase P-4MMP P-4MMPOH, but it enriched must considerably...

Fluid ingestion is necessary for life, and thirst sensations are a prime motivator to drink. There evidence of the influence oropharyngeal stimulation on water intake in both animals humans, but how those oral sensory cues impact ultimately amount liquid ingested not well understood. We investigated which trait(s) beverage quenching efficacy liquids perceived ingested. deprived healthy individuals food overnight (> 12 hours) make them thirsty. After asking drink fixed volume (400 mL) an...

Abstract The Mediterranean diet, considered one of the healthiest in world, is characterized part by major source its fat, which extra virgin olive oil (EVOO). Among health benefits consuming EVOOs presence phenolic compounds, have been shown to lower incidence coronary heart disease and are suspected providing many other benefits. These compounds also contribute flavor EVOO, adding both specific pungency throat bitter notes that valued connoisseurs but reported be unpleasant naïve...

Perceptions of food vary as a function an individual's genetic factors, such the set alleles coding for their taste, irritation, and olfaction receptor proteins. We established direct link between individual differences in sensitivity to glucosinolates, family bitter compounds vegetables roots, variations taste (hTAS2R38) these compounds. These perception nutrients likely evolved influence ingestion. Bitterness pungency are both believed signal potentially harmful our foods, but consumption...

Current research strongly suggests that phenolic compounds in extra virgin olive oil (EVOO) are potent preventive and therapeutic agents against metabolic diseases associated with inflammation oxidative stress. Oleocanthal (OC) oleacein (OA) two of the most abundant promising EVOO phenolics. To fully establish their health-promoting efficacy, additional animal studies human clinical trials must be conducted, but sourcing both at gram scale, reasonable cost, ease access remains a challenge....

Abstract The Mediterranean diet, considered one of the healthiest in world, is characterized part by major source its fat, which extra virgin olive oil (EVOO). Among health benefits consuming EVOOs presence phenolic compounds, have been shown to lower incidence coronary heart disease and are suspected providing many other benefits. These compounds also contribute flavor EVOO, adding both pungent bitter notes that valued connoisseurs but reported be unpleasant naïve consumers. Here, we...