OPTIMIZATION OF FERMENTATION PROCESS ON THE GABA CONTENT AND QUALITY OF FERMENTED RICE FLOUR AND DRY FERMENTED RICE NOODLES

摘要

This research aimed to investigate which process of fermentation can yield highrnlevels of γ-aminobutyric acid (GABA) in fermented rice flour. Six methods werernthus selected. It was found that process number 5 (fermentation of rice in waterrnfollowed by fermentation of flour in semimoist state) yielded the highest GABArncontent of 25.63 mg/100 g dry matter. To optimize the fermentation process ofrnflour, the control of fermentation of rice in water at temperature of 30C for 3 daysrnwas fixed and the fermentation of flour at different temperatures and times wasrnvaried. An experimental design by response surface method to optimize the fermentation of flour at temperature range of 28–42C for 0.2–6 days to increase thernGABA content was conducted. Fermentation at temperature of 35C for 3 daysrnyielded the highest GABA content of 36.82 mg/100 g dry matter.