Effect of salt reduction on nutritional, functional and sensory aspects of Anhui-style doubanjiang, a traditional Chinese broad bean paste

Abstract

This study aimed to reveal the effect of salt reduction on the nutritional, functional and sensory aspects of doubanjiang through preparing three sets of doubanjiang fermentation (Sample H, Sample M and Sample L) with different salt concentrations. The results showed that fermentation with lower salt concentration led to significantly higher amino acids concentrations in doubanjiang, while the organic acids concentrations were also slightly increased. For biologically active compounds, the concentrations of total flavonoids, total phenols and five monomer isoflavones in Sample L were all significantly higher than those in Sample M and Sample H. Moreover, better anti-oxidant ability was observed in doubanjiang samples fermented with lower salt concentration. Bacillus and Millerozyma genus were found to be closely related to the formation of amino acids and biologically active compounds in doubanjiang, while organic acids were highly correlated with Cronobacter, Erwinia, Trabulsiella, Enterobacter and Millerozyma genus. Through sensory evaluation and electric tongue, unsatisfactory sensory characteristics, such as lighter color, strong acid taste and off-flavor, were found in lower salt fermented doubanjiang samples. This indicated that lower salt concentration favored the nutrition and function of doubanjiang while negatively influenced doubanjiang flavor. This study deepened our understanding of the roles of salt concentration on doubanjiang fermentation and provided guidance for the further development of low-salt doubanjiang.