Exploring protein-mediated quality control mechanisms in Rice cooking behavior: from static protein content to dynamic architecture.

Rice proteins significantly influence cooking properties and eating quality, yet their dynamic roles during thermal processing remain unclear. This study systematically investigated protein-mediated mechanisms in rice cooking through in-situ structural analysis (SEM, CLSM) and enzymatic hydrolysis. Three rice cultivars with a common genetic background but differing in protein content were used (NJ > LSS-1 > LSS-2: 6.12 %, 7.20 %, and 8.15 %), and the results demonstrated that higher protein content correlated with denser protein networks, restricted starch gelatinization evidenced by retained 1047/1022 cm ratios. Protein aggregation inhibited water absorption during soaking, hydration at early steaming, and high-temperature gelatinization. The adhered layer mass significantly increased under protease treatment (0 %-5.0 %), rising from 0.35 to 0.91 g/25 g. A negative correlation (r = -0.30*, p < 0.05) between adhesion layer mass of protein and hardness highlighted protein-dependent texture regulation. These findings elucidate a three-stage protein regulation mechanism in rice cooking and propose protein modification as a strategy to tailor texture for consumer preferences.