Effect of five lactic acid bacteria starter type on angiotensin-I converting enzyme inhibitory activity and emulsifying properties of soy flour sourdoughs with and without wheat bran supplementation

摘要

The effect of five lactic acid bacteria (LAB), Lactobacillus plantarum, Lactobacillus sanfranciscensis, Lactobacillus brevis, Lactobacillus crustorum and Weissella cibaria on the angiotensin-I converting enzyme (ACE-I) inhibitory activity and emulsifying properties of soy flour enriched with wheat bran sourdough was investigated. Two sourdough were selected based on their ACE-I inhibitory activity: S-1 (3% wheat bran) and S-2 (0% wheat bran). All LAB strains adequately grew in both sourdoughs, S-2 samples registered significantly (P 0.05) higher total count compared to S-1 samples. Only L. plantarum and L. sanfranciscensis fermented sourdoughs exhibited ACE-I inhibitory activity with S-2 (S-2LP 52.8% and S-2LS 40.5%) having higher (P 0.05) activity than S-1 (S-1LP 36.5% and S-1LS 32.5%). Seventeen amino acids and low molecular weight peptides (0.2-3 kDa) were found in all sourdoughs and their control samples; sourdoughs had higher amino acid levels (P 0.05) than the control samples. Compared with control samples, sourdoughs exhibited lower emulsifying activity and higher emulsion stability. In conclusion, LAB starter type significantly affected the ACE-I activity and emulsifying properties of soy flour enriched with wheat bran sourdough. L plantarum and L. sanfranciscensis were the best strains and no wheat bran should be used in soy flour fermented with the two strains. (C) 2016 Elsevier Ltd. All rights reserved.