Primary Investigators: Nicolas H. von Cosmos and Charles G. Edwards
Organization: School of Food Science, Washington State University
Email: nickhogrefe@gmail.com, edwardsc@wsu.edu
Telephone: 509-335-6612
Academic Editor: Badal C. Saha
Received: 30 June 2016; Accepted: 29 August 2016; Published: 9 September 2016
Abstract: Specific vitamin requirements of the wine spoilage yeast, Brettanomyces bruxellensis, were evaluated. Previous studies had not taken into influences of ethanol or nutrient carry-over between sequential transfers into vitamin-omitted media. Knowing nutritional needs, limiting growth of the yeast in wine by selective removal of important vitamins was investigated. Six strains of B. bruxellensis were grown and sequentially transferred into single vitamin-omitted media. None of the strains required p-aminobenzoic acid, folic acid, nicotinic acid, myo-inositol, pantothenic acid, or riboflavin. While some needed thiamin depending on the absence/presence of ethanol, growth of all strains was greatly affected by biotin. Here, concentrations ≥0.2 µg/L were required to achieve yeast populations >106 cfu/mL for high (104 cfu/mL) or low (102 cfu/mL) initial inoculums. At concentrations <0.2 µg/L, culturabilities either remained unchanged or increased less than two logs after 40 days. Since the protein avidin binds irreversibly to biotin, egg whites containing avidin or the purified protein were added to a wine to diminish bioavailability of the vitamin. While biotin concentrations were reduced, populations of B. bruxellensis achieved were decreased by one to three logs, thereby supporting further development of biotin depletion strategies in winemaking.
Keywords: brettanomyces; nutrition; vitamins; biotin; avidin; wine
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