含二硫键的稻米蛋白质对米饭蒸煮食味品质的影响

以6种稻谷样品为材料,测定其蛋白质、二硫键含量,并通过二硫苏糖醇(dithiothreitol,DTT)处理打破蛋白质二硫键,观察米饭蒸煮质构品质处理前后的变化。进而研究大米中含二硫键的蛋白质对米饭食味品质的影响。结果表明,试验材料的谷蛋白含量和二硫键含量呈正相关。稻米中二硫键被破坏后,其蒸煮品质膨胀容积、吸水率、米汤干物质量、碘蓝值都呈增加趋势,米饭变软变黏。我们推测含二硫键的蛋白质在米饭蒸煮过程中,可能通过限制淀粉粒糊化,增加米粒吸水性等影响米饭的食味品质。

Impacts of proteins on cooking and eating properties of rice

6 rice cultivars were chosen to determine the impact of protein on cooking and eating qualities of rice.Their protein contends and disulphide bonds contend were examined and the differences of the cooking and eating qualities of rice with and without treatment with reduced agent dithiothreitol(DTT) were observed.The addition of DTT to cooking water aims to disrupt the disulphide bonds and keep them reduced.It was observed that the addition of DTT increased cooking qualities and the adhesiveness of cooked rice,while decreased the hardness of rice.From these observations,it was anticipated that the proteins with disulphide bonds can impact the cooking and eating properties of rice by restricting starch granule swelling and the water absorbability of rice.