Search

This study aims to investigate the effect of Lactiplantibacillus plantarum F25-4 assisted rice soaking water on the fermentation performance of Chinese rice wine (CRW). Compared to CRW using natural rice soaking water (NSR), CRW using rice soaking water assisted by L. plantarum F25-4 (LSR) exhibits an 80.69% increase in amino nitrogen content, a 26.03% increase in total acid content, a 79.54% increase in free amino acid content, and a 22.37% increase in volatile flavor content. The filtration efficiency of mash with rice soaking water by L. plantarum F25-4 was higher than that of NSR. Fourier transform infrared spectroscopy (FTIR), particle size analysis, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) revealed an increased average particle size of the rice soaking water assisted by L. plantarum F25-4, coupled with a reduction in the high molecular weight of soluble protein. This enhancement facilitated the utilization of rice protein by microorganisms and the transformation of flavor substances, contributing to flavor formation. L. plantarum F25-4 assisted in soaking and the reuse of rice soaking water to improve the quality of CRW by optimizing the utilization of rice protein. Therefore, this method lays the theoretical foundation for the sustainable reuse of rice soaking water. [Display omitted] • Lactiplantibacillus plantarum F25-4 facilitated the utilization of rice protein. • Rice soaking water assisted by L. plantarum F25-4 was reused for rice wine brewing. • Recycling rice soaking water improved the quality of rice wine. [ABSTRACT FROM AUTHOR]

A higher fermentation capability and quality of a rice wine was achieved, using mixed fungal (Rhizopus chinonsis R01, Asperigillus niger A20, Mucor pusillus M05 and Saccharomyces cerevisiae S10) starter fermentation of japonica rice supplemented with α-amylase (AM), glucoamylase (GAM) and acid protease (AP). Results showed that alcohol content, free amino acids (FAA) and volatile flavor substances concentrations were increased by 49.22%, 85.54%, and 25.71% compared with the control group respectively. To understand the role of enzymes during rice wine brewing, the effects of hydrolases on chemical and physical properties of cooking rice, on the yeast growth, enzyme productivity of molds were determined. Rice starch was hydrolyzed effectively by AM and GAM, the viscosity reduced significantly, the enzyme contact area expanded, which accelerated the further hydrolysis of japonica rice. Increase of hydrolysate promoted the fungi growth, while improved the ability of molds to produce enzymes. AP promoted the protease activity of M. pusillus M05 and A. niger A20, improved protein utilization, increased the content of FAA and formed higher level of flavor substances in rice wine. The results indicate that hydrolase addition can change the physic-chemical state of the mash to enhance microbial biotransformation and modify flavor metabolism. • Enzymes could increase the ethanol content of rice wine prepared by known starters. • Enzymes could increase the content of FAA and flavor components in rice wine. • Enzymes increased the system fluidity and the reaction area of cooking rice. • Added enzymes could promote the growth and enzymes productivity of fungi. [ABSTRACT FROM AUTHOR]

In the present study, rice wine was produced by mixed moulds starters fermentation. The influence of mixed moulds starters on enological parameters, free amino acids (FAAs), flavor compounds, and sensory characteristics of rice wine were respectively investigated. Results indicated that the contents of ethanol, amino acid nitrogen, umami and sweet FAAs in rice wine obtained from rice fermentation using starter of simultaneous inoculation of R. chinonsis R01, A. niger A20, M. pusillus M05 and S. cerevisiae S10 (RAM-S) were higher than that of Control one using wheat Qu. In addition, flavor compound data revealed that the aroma of rice wine using different starters mainly differed in the amounts of alcohols and esters. FAAs, flavor compounds, sensory evaluation and partial least squares regression (PLSR) analysis demonstrated RAM-S wine had the best sensory characteristics with higher contents of esters, nitrogen-containing, umami and sweet FAAs, and lower of bitter FAAs. These findings demonstrated that the starter RAM-S is promising to produce rice wine with high quality standards both in flavor and fermentation performance. • The rice wine prepared by RAM-S starter could increase the ethanol. • The effect of mixed moulds starter on flavor compounds of rice wine was evaluated. • Umami and sweet FAAs in rice wine by mixed moulds fermentation was increased. • The composition of starter contributed to the flavor compounds of rice wine. [ABSTRACT FROM AUTHOR]