Fermentation of hot pepper juice by Bacillus licheniformis to reduce pungency

Abstract

Capsaicin, an active component of hot pepper, has considerable health benefits; however, the pungency of hot pepper has limited its usage. This study aimed to reduce the pungency of hot pepper by fermentation to enhance its application in the food industry. Hot pepper juice was fermented by Bacillus licheniformis SK1230, which was previously isolated as a capsaicin-degrading bacterium. B. licheniformis SK1230 was inoculated into the juice of red or green pepper, and the mixture was then fermented for 19 days to determine the degradation level of capsaicinoids. It was observed that with a gradual increase in pH, the growth of B. licheniformis SK1230 increased to 1.0 × 10⁹ CFU/mL after day 1, and its viability persisted until the end of fermentation. The sugar content of green pepper drastically reduced at day 1 and that of red pepper reduced at day 5. The total polyphenol content of the medium containing red pepper was about 2-fold higher than that of the medium containing green pepper. The antioxidant activity of the medium containing red pepper was also higher than that of the medium containing green pepper; however, the activity gradually decreased during the course of the fermentation period. The capsaicinoid content of both types of peppers radically decreased at day 5. Thus, we suggest that a fermentation period of 5 days would be optimal for the degradation of capsaicin with minimal loss of antioxidant activity and would provide higher polyphenol content.