White wine production

For white wine production, the grapes usually were not stemmed. The crushed grapes were left for six to ten hours before the free-run (separated) juice was drawn off. The pomace was then pressed and the pressed pomace was washed as with red pomace. The fermentation of white musts was done in 2/3-full oak casks. The fermentation was watched daily. The yeast foam was removed. By the sixth day, the fermentation had slowed down sufficiently to then use a fermenting bung. The Italians often use a bag of sand, which they place over the bung-hole. He recommended fermenting room temperatures of 21°-27° C and cellar temperatures of 15.6°-21° C, preferring 15.6° C after the first year. 

Tirage involves filling the bottle with the base wine (wine from the first fermentation, produced by the usual techniques of white wine production), monovarietal or made from a mixture of wines (in both cases the grape varieties used are appropriate for this type of production) and the addition of a solution called tirage liquor. 

Figure 19.1 Schematic of the wine production process. Red and white wine production differs with respect to the timing of removal of the juice from the skins. Red wines are made from grapes fermented on the skins to allow for extraction of pigmented compounds. The post-fermentation steps of wine production vary by the style of the wine to be produced and its risk for microbial or oxidative spoilage.

As expected, fermentation rates by Saccharomyces 3xy viiih temperature. Ough (1964) reported that fermentations are relatively slow at 10 G/50 F compared with those conducted at 15°G/60°F or 27°G/80 F. Temperature also affects the population balance between Saccharomyces and non-Saccharomyces yeasts. In red wine fermentations (20°G/68°F to 30°G/86 F), Saccharomyces cerevisiae represents the dominant species (Sharf and Margalith, 1983), partially due to the warmer temperature of fermentation. At lower fermentation temperatures such as those used in white wine production, non-Saccharomyces yeasts can proliferate to yield much higher populations (Section 6.2.2). 

Fig. 1. An amplified outline scheme of the making of various wiaes, alternative products, by-products, and associated wastes (23). Ovals = raw materials, sources rectangles = wines hexagon = alternative products (decreasing wine yield) diamond = wastes. To avoid some complexities, eg, all the wine vinegar and all carbonic maceration are indicated as red. This is usual, but not necessarily tme. Similarly, malolactic fermentation is desired in some white wines. FW = finished wine and always involves clarification and stabilization, as in 8, 11, 12, 13, 14, 15, 33, 34, followed by 39, 41, 42. It may or may not include maturation (38) or botde age (40), as indicated for usual styles. Stillage and lees may be treated to recover potassium bitartrate as a by-product. Pomace may also yield red pigment, seed oil, seed tannin, and wine spidts as by-products. Sweet wines are the result of either arresting fermentation at an incomplete stage (by fortification, refrigeration, or other means of yeast inactivation) or addition of juice or concentrate.

Source Furfuryl occurs naturally in yarrow, licorice, sesame seeds, clove flowers, and tea leaves (Duke, 1992). Also detected in barrel-aged red, white, and model wines. Concentrations ranged from 3.5 mg/L in white wine after 55 wk of aging to 9.6 mg/L after 11 wk of aging (Spillman et ah, 1998). Identified as one of 140 volatile constituents in used soybean oils collected from a processing plant that fried various beef, chicken, and veal products (Takeoka et al, 1996). 

The only known chemical differences between grape varieties concerns the red pigments grapes with or without anthocyanins or grapes with or without anthocyanins diglucosides. These differences form the basis for the methods of characterizing vine products white wines and... 

Flavor characteristics of white Concord wine are completely different from those of red Concord wine. Although fruity, the foxy character is almost entirely lacking in the white wine. The white Concord wine is valuable in blends and in the production of baked dessert wines. 

Powdery mildew attacks leaves, shoots, and bunches. It is evidenced by an ash gray to white powdery growth on both the upper and lower surfaces of the leaves. Moreover, the disease attacks the bunches with the same ash gray/white powder showing up on the berries and stalks. Other than crop losses, the most negative aspect is that the disease causes off flavors in wine production. 

Comparison of antioxidant activities of several seasonings used in Asian cooking revealed exceptionally high TAC activities of dark soy sauces (47-147 mM) (L21). TAC of 1 ml of the most effective dark soy sauce was equivalent to 10 ml of red wine. It was pointed out that when evaluating the TAC of commercial products, attention should be paid to the addition of preservatives by manufacturers to the seasonings tested. Sodium benzoate (a preservative added to several seasonings) does not react significantly with ABTS +, but the sulfite content of certain white wines may lead to an overestimation of their TAC (L21). 

Malolactic fermentation is often viewed as the main source of polyamines in wine production (Marcobal et al., 2006). Thus, their presence is more significant in red wines than in white ones. Of white wines, sparkling wines, biologically aged wines, and botrytized wines might be the most susceptible to biogenic amine formation. 

Fermentation of the base white wine, used in producing the fortifying brandy, follows standard procedures. In Cognac, nonaromatic varieties, such as Trebbiano and Baco 22A, are used, where in Armagnac, Trebbiano is preferred. These cultivars have little varietal aroma, retain high acidity, and have limited alcohol production potential. In California, French Colombard, Thompson Seedless, and Tokay are the cultivars without distinctive flavor used to produce a brandy base wine. 

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