Study on possibility of the use of Kluyveromyces marxianus DMKU3 (tropical yeast) and thermoadapted Acetobacter pasteurianus TH3 in simultaneous vinegar production at higher temperature.

Abstract

Increasing temperature in recent years poses a substantial influence on fermentation industries and thus, huge cooling systems are required to maintain the optimum temperature leading to additional cost of production. In the present study, simultaneous vinegar fermentation with thermotolerant yeast (Kluyveromyces marxianus DMKU3) and thermo-adapted acetic acid bacteria (Acetobacter pasteurianus TH3) was performed at 37, 40 and 41°C with 10% initial glucose in shaking and static cultures. The highest ethanol production (4.952±0.02 % v/v) by tropical yeast and the highest acetate production (4.44±0.01 % w/v) was observed at 37 °C when both strains were added together at the beginning of fermentation. Moreover, it was found that higher vinegar production was achieved under shaking culture than the static culture. Moreover, the tropical yeast and the thermoadapted TH3 strains were able to use in simultaneous coconut water vinegar production at 37 and 40 °C successfully with an acetic acid production of 2.53±0.01% (w/v) and 2.34±0.03% (w/v) respectively. Thus, thermotolerant yeast and thermo-adapted bacteria could be successfully used in vinegar fermentation under higher temperature conditions.