Effects of mixed cultures of Saccharomyces cerevisiae and Lactobacillus plantarum in alcoholic fermentation on the physicochemical and sensory properties of citrus vinegar

Alcoholic fermentation is an essential step in producing high-quality vinegar and typically involves the use of pure yeast to initiate fermentation. In this study, two kinds of citrus vinegars were prepared with a pure culture of Saccharomyces cerevisiae and mixed cultures of Saccharomyces cerevisiae and Lactobacillus plantarum, respectively. During the alcoholic-fermentation stage, the contents of formic, lactic, and total organic acids were higher in the mixed cultures than in the pure culture. Mixed cultures citrus vinegar (MCCV) showed higher antioxidant activity than pure culture citrus vinegar (PCCV). The contents of sweet and umami free amino acids in MCCV were higher than those in PCCV. Meanwhile, flavor groups such as esters, alcohols, and aldehydes in MCCV also significantly improved. According to sensory analysis, MCCV showed higher intensity for sweet and umami attributes, as well as flowery and fruity attributes. Thus, mixed cultures of Saccharomyces cerevisiae and Lactobacillus plantarum in alcoholic fermentation can effectively improve the flavor and quality of citrus vinegar, thereby indicating additional economic benefits of fermentation. (C) 2017 Elsevier Ltd. All rights reserved.