超声辅助冷冻对面筋蛋白二级结构的影响

Effects of Ultrasound-assisted Freeze on Secondary Structure of Gluten Protein

本文通过对湿面筋蛋白冷冻时间和冷藏过程中二级结构变化的检测,研究超声改善冷冻食品品质的微观作用机制。用激光显微共聚焦拉曼光谱仪测定了不同环境下冷冻,冷藏不同时间的面筋蛋白二级结构,结果显示:传统环境下冷冻的湿面筋蛋白二级结构中的α-螺旋的含量随着冷藏时间的延长逐渐减少,无规卷曲的含量随着冷藏时间的延长逐渐增加;超声环境下冷冻的湿面筋蛋白二级结构随着冷藏时间的延长,其二级结构变化不明显。冻结完成时间的测定表明适宜的功率超声能加速湿面筋蛋白的冷冻过程,显示超声辅助冷冻是改善冷冻食品品质的实用技术。

The freezing time of wet gluten and the changes in protein secondary structure of wet gluten in freezing or cold storage were studied to investigate the microcosmic mechanism of the quality improvement of frozen food during the ultrasound-assisted food freezing. The changes in protein secondary slrueture in the wet gluten fi, ozen and cold storage for different times were investigated by Raxnan spectroscopy. In the conventional freezing process, a decrease of the amount of α-helixes in protein secondary structure in the wet gluten was found accompanied by an increase of the content of the extended β-sheet conformations. Under ultrasound-assisted food freezing conditions, no obvious changes in the protein secondary structure was found by prolonging frozen storage time. Besides, the freezing time of wet gluten was improved greatly when 360W ultrasound power was applied. Ultrasound-assisted freezing process was a suitable technique for food freezing.