Wines pantothenic acid

Vitamins are required for satisfactory development or function of most yeasts. Wickerham (177) devised a complete yeast medium which included eight vitamins biotin, pantothenic acid, inositol, niacin, p-aminobenzoic acid, pyridoxine, thiamine, and riboflavin. The concentrations of these growth factors varied widely with inositol in the greatest concentration and biotin in trace amounts. Many of these vitamins are considered major growth factors for yeast multiplication and development, as noted in several studies and reviews (178, 179, 180, 181, 182). Generally, the benefit of adding vitamins to musts and wines has not been established as a normal winery practice. This lack of response is because vitamins occur naturally in sufficient quantities in grapes and are produced by yeasts themselves (3). 

Pantothenic acid was reported in grape juices and wines by Perlman and Morgan (1945) in amounts of 0.007 to 0.100 mg. per liter. When added to either, it was retained during storage. Smith and Olmo (1944) found significantly higher amounts of pantothenic acid in the juice of tetraploid compared to diploid varieties. Lahrusca X vinifera interspecific hybrids were also higher in this vitamin than vinifera hybrids. 

Pantothenic acid, panthenol and panthenol ethyl ether are decomposed by heating the plate 30 min at 160° C. After spraying with ninhydrin reagent (No. 178A) and again heating briefly at this temperature, the / -alanine formed yields violet and the aminopropanol wine red. Decomposition is also quantitative by treatment with 10% trichloracetic acid... 

Lactic acid bacteria have very limited biosynthetic capabilities and, reflecting this, are described as nutritionally fastidious. Early work by Du Plessis (1963) noted that all strains of wine lactic acid bacteria required nicotinic acid, riboflavin, pantothenic acid, and either thiamine or pyridoxine. 

Lactones occur as natural odorants in aU major food commodities, including meat and meat products, milk, dairy products, cereals, fruits, vegetables and various beverages, such as tea, wine and spirits. Odour-active compounds in foods are y-and 5-lactones derived from aliphatic saturated and unsaturated y-hydroxycarboxyHc and 5-hydroxycarboxylic acids derived from fatty acids or sugars, but some lactones also arise from other precursors (e.g. mint lactone is a terpenoid compound and pantolactone is produced by hydrolysis of pantothenic acid via pantoic acid). Some lactones derived from aromatic hydroxycarboxyhc acids are also common compounds. The most important representatives of these compounds are phthahdes that are 3fL-isobenzofuran-l-ones (8-98) and coumarins (8-99) that are 2fL-l-benzopyran-2-ones (5-lactones of 2-hydroxycinnamic acids). 

Among secondary products, ketonic function compounds (pyruvic acid, a-ketoglutaric acid) and acetaldehyde predominantly combine with sulfur dioxide in wines made from healthy grapes. Their excretion is significant during the yeast proliferation phase and decreases towards the end of fermentation. Additional acetaldehyde is liberated in the presence of excessive quantities of sulfur dioxide in must. An elevated pH and fermentation temperature, anaerobic conditions, and a deficiency in thiamine and pantothenic acid increase production of ketonic acids. Thiamine supplementing of must limits the accumulation of ketonic compounds in wine (Figure 2.10). 

A deficiency in pantothenic acid causes the yeast to accumulate acetic acid but it has not been proven that the (unauthorized) addition of pantothenic acid to a fermenting must lowers the wine s volatile acidity originating from yeast. The production by yeasts of abnormally high levels of volatile acidity is probably due to the must s deficiencies in certain lipids. These deficiencies are most likely linked to deficiencies in pantothenic acid, which is involved in the formation of acetyl coenzyme A, responsible for fatty acid and lipid synthesis. 

Effectively, the volatile acidity of the wine tends to increase during the restarting of a stuck fermentation. This generally occurs when the yeasts encounter unfavorable conditions. Certain yeast strains are more predisposed to forming it than others. The addition of 50 mg of pantothenic acid per hectoliter (not authorized by EU legislation) not... 

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