超声辅助冷冻对湿面筋蛋白中冰晶粒度分布及总水含量的影响

Effects of ultrasound-assisted freezing on total water content and ice crystals size distribution in frozen wet gluten

超声辅助食品冷冻过程是一种新的技术。本文通过对湿面筋蛋白中冰晶粒度分布及总水含量的检测,探讨超声改善冷冻食品品质的微观作用机制,为超声冷冻新技术在食品化工中的应用奠定化学工程学基础。测定了有无超声环境下冷冻的湿面筋蛋白经过不同冷冻贮藏时间后总水含量,结果显示:随着冷冻贮藏时间的延长,超声环境下冷冻的湿面筋蛋白中总水含量比传统环境下高。用扫描电镜和压汞仪间接观察和分析了冷冻的湿面筋蛋白中冰晶的形状和粒度分布。研究表明,适宜的功率超声辅助下,冷冻过程能在湿面筋蛋白内部形成细小且分布均匀的冰晶体,减少面筋蛋白网络结构的破坏,从而改善冷冻食品的品质。

The ultrasound-assisted freezing process is a novel technique for food freezing. The total water content and ice crystals size distribution in frozen wet gluten were studied for understanding how ultrasound improves the quality of frozen food intrinsically, and establishing the engineering base for applying the ultrasound-assisted freezing novel technique to food engineering. The total water content of wet gluten frozen under different conditions and preserved with different times was determined. It was found that the total water content of wet gluten frozen in ultrasonic field was higher than that of the conventional freezing process after the frozen storage time. The shape and size distribution of ice crystals in the frozen wet gluten were studied indirectly by microscopy and mercury porosimeter. It was revealed that the ultrasound-assisted freezing process could result in uniform distribution of small ice crystals formation to reduce the deterioration of gluten network and so as to improve the quality of frozen food.