Yeasts in grape juice

Pederson, C.S., Albury, M.N., and Christensen, M.D. 1961. The growth of yeasts in grape juice stored at low temperatures. IV. Fungistatic effects of organic acids. Appl. Microbiol. 9, 162-167. 

Gunes G, Blum LK, Hotchkiss JH. 2005. Inactivation of yeasts in grape juice using a continuous dense phase carbon dioxide processing system. J Sd Food Agr 85 2362-2368. 

Most wine is prepared by die fermentation of die glucose in grape juice by yeast ... 

Sodium bisulfite is used in almost all commercial wines to prevent oxidation and preserve flavor. It releases sulfur dioxide gas when added to water or products containing water. The sulfur dioxide kills yeasts, fungi, and bacteria in grape juice before fermentation. When the sulfur dioxide levels have subsided, after about twenty-four hours, fresh yeast is added for fermentation. 

All amino acids, except proline, may be used by Saccharomyces cerevisiae in grape juice fermentation. Amino acids can be directly used to synthesize proteins. However, the amino acid composition of the grape juice is not necessarily similar to the needs of the cell. For that reason, yeasts must use the remaining amino acids to synthesize those which it lacks (Hensche and Jiranek 1993 Ribereau-Gayon et al. 2000b). In this case, ammonia is incorporated into other amino acids whereas the carbon skeleton is metabolized by the cell. 

Grbin, P. R., Henschke, P. A. (2000) Mousy off-flavour production in grape juice and wine by Dekkera and Brettanomyces yeasts. Australian Journal of Grape and Wine Research, 6, 255-262. 

Barata, A., Correia, R, Nobre, A., Malfeito-Ferreira, M., Loureiro, V. (2006). Growth and 4-ethylphenol production by the yeast Pichia guilliermondii in grape juices. Am. J. Enol. Vitic., 57, 133-138. 

In addition to S02 and antibacterial proteins/peptides, medium-chain fatty acids produced by yeast during alcoholic fermentation have also been implicated in the inhibition of malolactic bacteria (Carrete et al, 2002 Edwards and Beelman, 1987 Lonvaud-Funel et al, 1985). Inhibition of Saccharomyces species and some LAB by medium-chain fatty acids has been reported in grape juice and silage (Pederson et al, 1961 Woolford, 1975). Although this hypothesis has not been conclusively shown, Lonvaud-Funel et al (1985) and... 

There has been a growing application of metabolomics to wine yeast and fermentation as more people have recognized the power of these techniques. One application of metabolomics has been to study the interactions of yeast during fermentation. Howell et al. (2006) used metabolic profiling to study how multiple strains of Saccharomyces spp. grown together in grape juice affect the flavor and aroma compotmds in the fermented wine. 

A family started a batch of wine by adding yeast to grape juice and placing the mixture in a sealed bottle. Two weeks later, the bottle exploded. What metabolic reactions—and specifically, what product of those reactions—caused the bottle to explode ... 

PiLONE, A.D., GJ. PiLONE, and B.C. Rankine. 1973. Influence of yeast strain, pH and temperature on degradation of fumaric acid in grape juice fermentation. Am.f Enol Vitic. 24(3) 97-102. 

Terrell, R.R.,J.R. Morris, M.G. Johnson, E.E. Gbur, andDJ. Makus. 1993. Yeast inhibition in grape juice containing sulfur dioxide, sorbic acid and dimethyldi-carbonate./. Food Sci. 58(5) 1132-1135. 

Once isolated, the unknown microorganism(s) can be better characterized using the methods detailed in the following sections for identification. This chapter describes those classic methods used to characterize and identify yeasts and molds (Section 15.3) as well as bacteria (Section 15.4) found in grape juices and wines. 

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