Wine fermentation production

Cellulases endo-1,4 p-glucanase, cellobiohydrolase, p-glucosidase Brewing, cereal processing, fruit and juice processing, food fermentation, wine production, alcohol fermentation, vegetable processing. 

Spontaneous fermentations are used for wine production in Erance, some other European countries and in South America. In recent years, smaller California wineries have begun experimentation with spontaneous fermentations as well. They generally start more slowly than fermentations inoculated with commercial dried yeast, are more difficult to control, and may suffer from growth of undesirable contaminants. However, it is claimed that the resulting wines possess better organoleptic properties, particularly more complex flavor and aroma. 

If the grapes are destined for use in wine production, no thermal processing steps are involved. The grapes are ground, and the entire mass is fermented. The fermented juice is then decanted from the pulp, or lees, and moved into other tanks for aging. 

Spontaneous emulsification, 10 127 Spontaneous fermentations for wine production, 26 468 Spontaneous fission, 21 304-305 Spontaneous ignition temperature, 7 438t... 

Table 10.1 gives a summary of the main by-products of fermentation by yeasts and other microbiological activities which can be identified in distilled spirits from different raw materials, like fruits, wine, grain, sugar cane, or other carbohydrate-containing plants. Since the sensory relevance of a flavour compound is related to its odour thresholds and odour quality. Table 10.1 presents also odour qualities and a review of threshold values of the fermentation by-products in ethanol solutions [9-10] and/or water [11-14] (Christoph and Bauer-Christoph 2006, unpublished results). 

San Joaquin Valley (Calif.) table wines (wines with less than 14% ethanol) represent about 80% of wine production in California. In two large wineries there, the malo-lactic fermentation is inhibited and does... 

Ethyl acetate is a product of yeasts and a normal component of wine. Its level can be increased by Acetobacter contamination, although most wines showing excess volatile (acetic) acid do not necessarily contain excess ethyl ester initially. It is quite possible to obtain brandy of normal composition and quality by continuous distillation of newly fermented wine containing excess acetic acid, e.g., 0.1%. On the other hand, ethyl acetate can be formed in continuous columns, particularly if the distillation conditions provide for a relatively high ethanol concentration on the feed tray or immediately below. Since acetic acid is weakly yolatile in all mixtures of ethanol and water, it does not appreciably distill upward. Therefore there is no opportunity for acetic acid to combine wtih ethanol in tray liquids normally of high ethanol concentration. 

Cessation of fermentation is one of the technical problems in botrytized wine production that needs further research and development. Dimethyldicarbonate (DMDC) is now considered a reliable inhibitor which could replace some of the S02. Although DMDC has proven suited for treating wines especially just before bottling, its use in Sautemes production has been investigated (Divol et al., 2005). The results showed that DMDC at a rate of 100-200 mg/1 stopped fermentation but did not replace the antioxidant functions of SO2. Sulfite addition was necessary to limit wine oxidation and yeast reactivation. 

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. 

Tamarind (Tamarindus indica L.) is an important tropical tree widely grown in India. Although its fruit can be used for wine production, its wine is not preferred due to its high acidity. An attempt has been made to convert its wine into vermouth of acceptable quality (Lingappa et ah, 1993). In this process, the base wine was made from tamarind fruit (50 g/L), at 0.9% acidity, followed by raising the TSS to 23 °Brix and adding 150 ppm sulfur dioxide. Fermentation was conducted by S. cere-visiae var. ellipsoideus at 27 1 °C. Both dry and sweet vermouths, with 17% alcohol content, were found acceptable. 

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. 

Juice clarification is an important technique in North Coast quality wine production. Removal of suspended solids from the juice prior to fermentation results in a wine described as fruity, clean tasting, fresh, delicate (19, 20). Level of solids in clarified juice ranges from 0.5 to 2.5 percent. Juice clarification also reduces the level of elemental sulfur, reducing potential for later H2S production. 

European special-purpose rotating tanks have been used successfully by at least one North Coast winery, but the cost of the equipment and space required has discouraged expansion of this facility. Continuous fermentation systems have been introduced in foreign countries but are only in very limited use in northern California. Dangers of contamination, cooling difficulties, and the need for a continuous flow of must make them unsuited for premium wine production. Heating is another way to liberate color and tannins from the skins but until recently all experiments have produced wines of inferior quality and, therefore, have not been used in the coastal counties of California. 

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. 

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