Biochemical Changes and Sensory Evaluation of Soy Iru Produced Using Starter Culture

Abstract

Soybean (Glycine max L.) was processed into iru using Bacillus subtilis SBI 13 and Leuconostoc mesenteroides as starter culture and calabash as fermenting container. The fermenting soya beans were analysed for pH and titratable acidity, free amino acids and total soluble sugar. The Enzymatic analysis (protease, amylase and lipase) was also carried out. The combination of Bacillus subtilis and Leuconostoc mesenteroides showed higher protease and amylase activities than when they were used singly. The samples were fermented for 3 days after which were evaluated for sensory qualities. The pH of the samples ranged from 7.08 to 8.88, the titratable acidity ranged from 0.58 to 0.73, the total free amino acids ranged from 1.10 to 6.29% and the total soluble sugar ranged from 18.02 to 29.29%. All the iru samples were acceptable by the sensory panelists but the soy iru fermented with both Bacillus subtilis SBI 13 and Leuconostoc mesenteroides SBI 15 (Bacillus + LAB soy iru) was the most preferred.