内源性蛋白质调控对米饭消化特性的影响

Effects of Endogenous Protein Modulation on the Digestive Properties of Cooked Rice

摘要:

目的 探究烹饪过程中大米蛋白质减少量对米饭消化特性的影响，揭示米饭淀粉-蛋白质复合物的交联机制。方法 基于电饭煲烹饪体系的米汤收集装置，通过降低蛋白质质量（149.31~258.02 mg），比较不同处理组米饭的质构特性、水分分布与体外消化率，解析蛋白质减少量对淀粉-蛋白质交联的分子作用机制。结果 降低大米蛋白质质量可显著提高米饭的体外消化率，当蛋白质减少量为227.47 mg时，淀粉体外消化率由（85.89±3.03）%提升至（94.17±1.08）%，蛋白质体外胃消化率由（38.88±1.75）%提升至（43.55±2.25）%。体外胃消化0、1、2 h样品的淀粉-蛋白质交联程度均显著下降。结论 降低大米中的蛋白质质量能够抑制淀粉-蛋白质复合物的形成，促进淀粉与蛋白质酶切位点暴露，从而显著提高米饭的体外消化率。

Abstract:

Objective This study explored the effects of protein reduction during rice cooking on the digestive properties of cooked rice, aiming to reveal the cross-linking mechanism of starch-protein complexes.Method The rice-water collection device integrated into a rice cooker system was employed to regulate the protein reduction amount ranging from 149.31 to 258.02 mg. The textural properties, moisture distribution, and in vitro digestibility of cooked rice in different groups were systematically compared. In addition, the molecular mechanism by which protein reduction influenced starch-protein cross-linking was investigated.Result Protein mass reduction significantly improved the in vitro digestibility of cooked rice. When the protein reduction amount reached 227.47 mg, the in vitro starch digestibility increased from (85.89±3.03)% to (94.17±1.08)%, while the in vitro gastric protein digestibility increased from (38.88±1.75)% to (43.55±2.25)%. Moreover, the degree of starch-protein cross-linking significantly decreased after 0 h, 1 h, and 2 h of in vitro gastric digestion.Conclusion Protein mass reduction during rice cooking inhibited the formation of starch-protein complexes, thereby exposing more enzymatic hydrolysis sites in starch and protein. This structural modification contributed to the enhanced in vitro digestibility of cooked rice.