An investigation of simultaneous pineapple vinegar fermentation interaction between acetic acid bacteria and yeast

Simultaneous pineapple vinegar fermentation interaction between two microorganisms was investigated, wherein the interaction between acetic acid bacteria (AAB) Acetobacter aceti WK and a flocculate yeast Saccharomyces cerevisiae M30 was conducted. The inoculated yeast was allowed to ferment for 1 - 4 days prior to inoculating the AAB into the fermenting mash. Non-aerated conditions for alcohol fermentation were used to enhance the ability of S. cerevisiae M30, whereas aeration was supplied to assist vinegar fermentation by A. aceti WK. During aeration, alcohol production by S. cerevisiae M30 was drastically decreased and observed, while A. aceti WK cells increased for two more log cycles within 10 days and produced 1.6 – 2.1% acetic acid. By this simultaneous fermentation, the commensalisms interaction was primarily observed by supplying of alcohol to AAB by yeast, while the AAB provided nothing to yeast. The accumulating acetic acid produced by A. aceti WK caused an antagonistic effect on growth of S. cerevisiae M30.