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Summary: This study investigated the effect of Lactobacillus plantarum F25‐4 assisted rice soaking (LAS) on the cooking properties of japonica rice used for Chinese rice wine (CRW) production. The effects of LAS and natural soaking were compared based on the chemical composition, thermal characteristics, infrared spectroscopy and sodium dodecyl sulphate‐polyacrylamide gel electrophoresis of rice flour. After LAS, the protein content of the rice was reduced by 17.63%, and the initial temperature (To), peak temperature (Tp) and conclusion temperature (Tc) were reduced by 36.86%, 17.89% and 1.61%, respectively, as revealed by differential scanning calorimetry analysis. The Zeta (ζ) potential value changed from −8.75 mV to −3.99 mV, and the minimum cooking time was reduced by 40% to only 15 min. The viscoelasticity of LAS rice increased after gelatinisation, as confirmed by confocal laser scanning microscope images. The glutelin precursor of the LAS rice disappeared, and the disorder of protein secondary structure increased, but there was no significant difference in the starch crystal area. LAS effectively improved the cooking properties of rice by changing the protein configuration on the surface of starch granules and reducing protein adsorption, leading to increased starch water absorption and decreased rice gelatinisation temperature. Our research suggests that LAS can reduce the cooking temperature of rice in CRW production, thus saving steam consumption during cooking. [ABSTRACT FROM AUTHOR]

BACKGROUND: Black rice contains a variety of bioactive substances that contribute to the high nutritional value of black rice wine (BRW). However, the dense bran layer of black rice retards the fermentation rate and reduces the dissolution of active components. Hence, this study aims to investigate the effects of pre‐gelatinization (PG) before cooking and cellulase (CE) addition during fermentation on the fermentation performance of BRW and its antioxidant activity. RESULTS: PG combined with CE treatments (PGCE) increases the alcohol content, free amino acid content, volatile flavor content and total antioxidant activity of BRW by 90.81%, 15.36%, 38.05% and 19.56%, respectively, compared with the control group. Scanning electron microscopy, low‐field nuclear magnetic resonance and texture properties analysis indicate that PG treatment increases gelatinization degree of starch during cooking, decreases bound water content in cooked black rice and promotes unbound water release. CE destroys the aleurone layer structure, facilitates the release of unbound water and the exposure of rice starch, thus increasing the reaction area and extravasation content significantly, which is beneficial to microbial growth and fermentation. Incomplete aleurone layer also promotes the dissolution of anthocyanins, phenols and other active substances, increasing the antioxidant activities of BRW. CONCLUSION: PG and CE treatments reduce the fermentation time and improve the quality of BRW by destroying the black rice structure. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]