Differential Effects of Pre-Fermentation with Different Lactic Acid Bacteria Strains on the Structure, Functionality,...

This study selected three lactic acid bacteria strains (Lactiplantibacillus plantarum CGMCC 1.12974, Limosilactobacillus fermentum CICC 22704, and Lactobacillus acidophilus CICC 22162) to pre-ferment brown and polished glutinous rice grains followed by semi-dry milling, aiming to systematically compare the differential effects of various strain treatments on the structure, functionality, and flavor of glutinous rice flour. Pre-fermentation decreased protein content (11.23-20.80% in polished flour, 0.14-2.45% in brown flour), enriched γ-aminobutyric acid (GABA, up to 6.94 mg/100 g), increased relative crystallinity and gelatinization enthalpy, and altered hydration properties. Dumplings from fermented flours showed higher soup transmittance (up to 44.93% in the brown rice group), reduced hardness (24.82-67.32%) and chewiness, and improved cohesiveness and resilience. Volatile profiles shifted towards higher acids and esters and lower alcohols, aldehydes and ketones, with strain-specific features. Redundancy analysis confirmed that starch became the dominant texture-determining factor after fermentation. Among the three strains, Lp. plantarum CGMCC 1.12974 exhibited the best improvement for most quality attributes. In conclusion, pre-fermentation of rice grains effectively enhances whiteness, GABA content, textural softness, and flavor diversity of semi-dry milled glutinous rice flours.