“ The process required for fermented foods were present on earth when man appeared on screen…when we study these foods, we are in fact studying the most intimate relationship between man, microbe and food.”
Fermentation technology is one of the oldest food technologies that have been used for several thousand years as an effective and low cost means for preserving foods and beverages. Wines are originally Middle East and European drinks, although almost every country now produces them. Using grapes of species Vitis vinifera large-scale production of wines is carried out. Grape juice is a good source for wine production because of its high concentration of sugar, other nutrients, natural acidity (that can inhibit unwanted growth of microorganisms) and the capability to produce pleasant aroma and flavor. Wine is one of the functional fermented foods that have many health benefits. Commercially, wine is produced by the fermentation of yeast, which involves the conversion of sugar to alcohol. Louis Pasteur often used to state ‘wine is the most healthy and most hygienic of beverages’. There is some recent scientific evidence also in support of this view, since moderate wine consumption reduces the risk for coronary heart disease (CHD).
Enzymes are widely used in fruit juice and brewing industries to achieve specific objectives, which cannot be otherwise achieved. In addition, brewing industry employs varied, but specific, strains of yeast, e.g., Saccharomyces cerevisiae, S. carisbergensis, etc., for fermentation of the brew. The cloudiness of fruit juices and wines is mainly due to pectins, which may exhibit various degrees of methyl esterification, and are usually associated with other plant polymers and even cell debris. The pectins are digested by pecteolytic enzyme activities (i) polygalacturonase (random digestion of pectin), (ii) pectin esterase (removal of methyl esters and release of methanol; pectin becomes degradable by polygalacturonase), (iii) pectin lyase (cleaves pectins into oligosaccharides even without pectin esterase action), and (iv) hemicellulase (a mixture of enzymes degrading hemicellilose). These enzymes have pH optimum between 4 and 5 and optimum temperature below 50o C. Treatment of fruit pulp with the proteolytic enzyme mixture gives the following benefits: (i) elimination of juice/wine cloudiness, (ii) reduced solution viscosity, (iii) increased juice yields, e.g., a 15% increase in case of white grapes, and (iv) shorter fermented period in case of wine making. In addition, (v) pectins stabilize the cell debris in a colloidal state; but once pectins are digested, the debris precipitated is removed by filtration.
There are bacteria in wine that may be beneficial for people’s health. In latest study, researchers have isolated 11 strains of bacteria from wine, including strains of Lactobacillus, which are also found in yogurt, as well as Oenococcus and Pediococcus bacteria, which are associated with wine making process.
Many studies have reported that the best foods to deliver probiotics are the dairy fermented products, so that the probiotic properties of wine related Lactobacillus could be studied. But, nowadays there is need for novel and non-dairy probiotics, from the increasing number of lactose intolerance cases occurring in the world population coupled with the unfavorable effect of cholesterol contained in fermented dairy products.
Probiotics are live organisms that can bring health benefits when consumed in right amounts. Probiotics may be beneficial primarily for maintaining a healthy community of gut bacteria and bowel function and also aids in lowering the body’s cholesterol level. Researchers have examined that bacteria isolated from wine could survive in conditions similar to those found in human gastrointestinal system. They found that the bacteria could survive when exposed to simulated gastric juice, bile and lysozyme. The probiotic properties of the lactic acid bacteria isolated from wine are similar to those of probiotics that come from foods like dairy products such as fermented milk or yogurt and dry sausages, and foods of plant origin such as olive, fruits, cereals, meat or fish. Even though the moderate consumption of wine may confer health benefits, but it does not provide a sufficient amount of probiotics to be beneficial, because many of the bacteria are eliminated during a process called sulfating, which stabilizes wine.