Optimization of alcohol-free beer prepared from fermented wort by Pichia kluyveri var kluyveri

Abstract

An increasing number of studies have examined the preparation of alcohol-free beer beverages by special yeast fermentation methods. Here, Pichia kluyveri var kluyveri was used to prepare alcohol-free beer beverages by the fermentation of wort. The single-factor test method and response surface method were used to determine the optimal preparation parameters for alcohol-free beverages. The optimal fermentation process was as follows: fermentation without shaking; original wort concentration, 12 °P; fermentation temperature, 20.41 °C; inoculation quantity, 2.69 % (v/v); and fermentation time, 180.44 h. The feasibility of the process was verified by the triangle bottle test and fermentor test. Lastly, the fermented beverage was modified with a sour taste agent, and samples with 0.4 per thousand citric acid added had better taste. This method has the advantages of full body, rich fruit aromas, short fermentation period, and no additional equipment input. Thus, this method is suitable for wide use.