Effect of fermentation with Tetragenococcus halophilus and Zygosaccharomyces rouxii on selected non-volatile taste compounds in soybean protein hydrolysates

Abstract

This work was focused on investigating the effect of fermentation with Tetragenococcus halophilus and Zygosaccharomyces rouxii on the flavor characteristics of soy protein hydrolysates (SPH). The sensory attributes and non-volatile taste compounds of SPHs were analyzed using high performance liquid chromatography, electronic tongue and sensory evaluation. The results demonstrated that fermentation could effectively increase the contents of amino nitrogen, total acids, organic acids (especially lactic acid), umami amino acids (growth rate ranging from 10.9% to 30.6%) and sweet amino acids (increased by 7.8%–62.0%) compared with control groups, contributing to improve the acidity, as well as umaminess and sweetness taste of samples. Principal component analyses and partial least square discriminant analyses confirmed the substantial impacts on the non-volatile taste characteristics of SPHs by lactic acid bacteria (LAB) and yeast fermentation, especially for the flavor profile of the sample with Aspergillus oryzae hydrolysis and sequential addition of LAB and yeast (SFH-2), and the sample with commercial protease hydrolysis and simultaneous addition of LAB and yeast (SH-1). These findings provided a theoretical basis for enhancing the flavor intensity of soybean protein hydrolysates.