Aromatics white wine

An important sulfide is methional (8-37). Methional in beer and wine is formed by the activity of microorganisms. It is partly reduced to the corresponding alcohol methionol (8-13) and reaction with acetyl-CoA yields 3-methylthiopropyl acetate (8-129), which is an important component of various fermented foods. Another ester of acetic acid 3-(methylthio)hexyl acetate is a component that posseses attractive tropical fruity notes on dilution. The less odoriferous (-)-(J )-enantiomer (8-130) is reminiscent of passion fruit, while the (-l-)-(S)-form has a more herbaceous odour. The odour thresholds of these thiols in air are 0.10 ng/1 and 0.03 ng/1, respectively. Both isomers have been found in passion fruit (Passiflora edulis, Passifloraceae), guava Psidium guajava, Myrtaceae) and aromatic white wines. Methyl-3-(methylthio)propionate, or pineapple mercaptan (8-131), has a flavour reminiscent of pineapple. S-Methylthiohexanoate (8-132) is a component of the durian fruit smell. Condensation of methional with ethanol yields (Z)-2-(methylthio)methylbut-2-enal also known as 2-ethylidenemethional (8-133), which is an important component of potato chips aroma. It also occurs in... 

Various aromatic white wines compose the fonrth group. Sometimes, these wines are famons and made from premium varieties. Their geographical territory has remained limited to their original regions. An exhaustive list of these wines is not... 

Aromella Traminette xRavat 34, 2013 Aromatic white wine grape... 

Aromella (TraminettexRavat 34, 2013). Aromella was released to provide an aromatic white wine cultivar (Reisch et al., 2013a, 2014b) that is highly productive and very winter hardy. Wines are described as having elements of pineapple, honeysuckle, citrus peel and muscat. Vines are productive and resistant to disease. 

Reisch, B.L, Luce, R.S., Mansfield, A.K., 2013a. Aromella . An Aromatic White Wine Grape. On http //www.horLcomeU.edu/reisch/grapegenetics/cultivars.html. 

The addition of exogenous glycosidases enhance greatly aromas in wines in relation with the aromatic potential of grape varieties. Tastings confirm that the improvement is obvious for red and for white wines. Wines are always judged more fruity and more intense. 

Thibon, C., Shinkaruk, S., Jourdesa, M., Bennetau, B., Dubourdieu, D., and Tominaga, T. (2010). Aromatic potential of botrytized white wine grapes Identification and quantification of new cysteine-S-conjugate flavor precursors. Anal. Chim. Acta 660,190-196. 

Vermouth is officially classified as an "aromatized fortified wine," referring to its derivation from a white base wine fortified and infused with a proprietary set of different plant parts barks, seeds, and fruit peels. These are collectively termed botanicals. Vermouths are particularly popular in Europe and in the United States (Amerine et al., 1980 Griebel, 1955 Panesar et al., 2009). The term "vermouth" is derived from the German word for wormwood Wermut. It is supposedly derived from Wer (man) and Mut (courage, spirit, manhood Pilone, 1954). When vermouth was introduced into Bavaria in the first half of the seventeenth century, by the Piedmont producer Alessio, Artemisia absinthium was probably translated literally as Wermutwein. When it reached France, it was changed to vermouth (Liddle and Boero, 2003). 

Vermouth was initially made from red wine, produced to be slightly sweet, and possess a mildly sharp after taste. However, around 1800, dry vermouth made its appearance in the Marseilles, France. In 1813, Joseph Noilly created the style that came to be known as dry or French vermouth. By 1855, Noilly s son, Louis, and his brother-in-law, Claudius Prat, were producing Noilly Prat dry vermouth in southern France. This white, wine-based, fortified drink, is now flavored with as many as 40 aromatic herbs and flavorings, such as juniper, cloves, quinine, orange peel, nutmeg, and coriander (The New Encyclopaedia Britannica, 1995). 

Peinado, R.A., Moreno, J., Bueno, J.E., Moreno, J.A., Mauricio J.C. (2004a). Comparative study of aromatic compounds in two young white wines subjected to pre-fermentative cryomacera-tion. Food Chem., 84, 585-590. 

Brown, A.E., Adikaram, N.K.B. (1983). A role for pectinase and protease inhibitors in fungal rot development in tomato fruits. Phytopathologische Zeitschrift, 106, 239-251 Cabaroglu, T., Razungles, A., Baumes, R., Gunata, Z. (2003). Effect of fining treatments on the aromatic potential of white wines from Muscat Ottonel and Gewurztraminer cultivars. Sc. 

The perception threshold of CS2in water is around 20 fJig/L, a little lower than that recorded by Spedding and Raut (1982) in white wines (38 (Jig/L). Tasters can recognise this substance at concentrations of around 150 p-g/L. However, at lower levels, the aromatic tone of the wine changes and it tends to mask some fruity aromas, while it can enhance the mouldy aroma or even that of volatile phenols and the wine can be described as lacking limpidity. 

In addition to their importance for white wine stability, proteins seems to be involved in other aspects of wine quality. For example, it is recognized that proteins can interact with aromatic compounds (Lubbers et al., 1994), influence the perception of wine body in the mouth, and, due to their surface properties, affect foam formation and stability in sparkling wines (Brissonet and Maujean, 1993). 

More recently, a 2 1 mixture of pentanermethylene chloride has been used to extract the aromatics from white wines (35). These investigators used a continuous liquid/liquid extractor for eight hours to remove the aromatics the organic phase was then concentrated to 1 ml volume using a Vigreux column. Such a procedure should have application in studies on fermentation broths. 

Ethyl acetates of fatty acids have very pleasant odors of wax and honey which contribute to the aromatic finesse of white wines. They are present at total concentrations of a few mg/1. 

The concept of thresholds , always applied in a given medium (water, dilute alcohol solution, white wine or red wine), is used to indicate the characteristics of various aromatic substances ... 

The use of certain pectolytic enzyme preparations to facilitate the extraction or clarification of white must may lead to an increase in the vinyl-phenol content of white wines and a deterioration of their aromatic qualities (Chatonnet et al 1992a Dugelay etal., 1993 Barbe, 1995). Indeed, certain industrial pectinases, made from Aspergillus niger cultures, have a cinnamyl esterase (CE) activity. This enzyme catalyzes the hydrolysis of tartrate esters of hydroxycinnamic acids in must during the pre-fermentation phase (Figure 8.7). Feruhc and j9-coumaric acids are then converted into vinyl-phenols during alcohohc fermentation due to the cinnamate decarboxylase activity of Saccharomyces cerevisiae. 

Amon and coworkers (1986, 1989) analyzed 37 wines affected by cork taint, using gas-phase chromatography, equipped with an olfactometry system and coupled with a mass spectrometer. They analyzed the compounds most frequently found, both in corked wine and their respective corks. Their findings are shown in Figure 8.13. These same authors ran triangular tests with a panel of twelve tasters and found that the perception thresholds for these compounds in a non-aromatic, dry white wine were particularly low (Table 8.11). 

Racking is not advisable for light, fresh, aromatic, dry white wines with high CO2 levels, generally aged in the vat for a few months after fermentation. If this type of wine is racked at all, care must be taken to keep aeration to a minimnm. 

It has been observed that the bonqnet of red and white wines develops after only a short period of bottle aging, generally when all the dissolved oxygen has reacted and the oxidation-reduction potential has reached its lowest value (<200 mV). This varies with the type of wine, its SO2 concentration and the type of closure (cork, etc.). High temperatures and light stimulate reduction in the medinm and modification of the aromatic characteristics. 

In contrast to heterocyclic aromatic amines, resveratrol (3,5,4Ctrihy-droxystilbene) and its isomers, natural phenofic compounds present in grape and wines, are beneficial to human health for many reasons primarily, there is a lower mortality from cardiovascular diseases observed in populations taking constantly a moderate amount of wine. SPE from red or white wine samples on LiChrolut EN and subsequent separation of the analytes by Hquid chromatography provides selective and fast analysis of resveratrol and its isomers [280]. 

Falque, E. Fernandez, E. Dubourdieu, D. (2001). Differentiation of white wines by their aromatic index. Talanta 45, 271-281... 

B. cinerea metabolizes aromatic terpenes including linalool, geraniol, and nerol in the formation less volatile compounds such as p-pinene, a-terpineol, and other oxides (Nigam, 2000). In addition, the mold produces esterases that degrade the esters, compounds that give many white wines their fruity character, and can also synthesize sotolon ( honey-like ) and l-octeno-3-ol (Nigam, 2000). 

Certain heterocyclic compounds are also important aromatic substances in wines, such as pyrazines in Cabernet Sauvignon and Sauvignon Blanc wines (see Section 8.2.11.1.7) and both enantiomers of 3-hydroxy-4,5-dimethyl-5if-furan-2-one (sotolon), which occur in white wines, sherries and are a key component of the typical aroma of aged Port wines. The precise chemical reactions leading to the formation of bouquet substances are not yet widely known. There are two types of reactions that produce bouquet constituents oxidation, which is characterised by the presence of aldehydes and acetals (e.g. in Madeira-type wines) and reduction (such as in quality table wines after a period of bottle maturation the flavour of low-quahty wines does not improve under the same conditions, but instead maturation often leads to a loss of freshness). During wine aging, glycosides of terpenic alcohols and... 

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