Xu Lijing, Wang Xin, Xu Yaping, Meng Junlong, Feng Cuiping, Geng Xueran, Cheng Yanfen, Chang Mingchang
College of Food Science and Engineering, Shanxi Agricultural University, Taigu 030801, China.
Shanxi Key Laboratory of Edible Fungi for Loess Plateau, Taigu 030801, China.
Foods. 2023 Aug 4;12(15):2948. doi: 10.3390/foods12152948.
Changes in the functional properties and structures of protein isolate (CSPI) in the process of freeze-thaw (F-T) cycles were explored. Remarkable alterations and the reduced content of protein ordered structure were revealed through structural analysis of CSPI after F-T treatments. The surface hydrophobicity and free sulfhydryl content of CSPI first increased and then decreased. However, after the F-T treatments, the carbonyl content of CSPI continued to increase. Similarly, the water holding capacity (WHC), oil holding capacity (OHC), and solubility of CSPI all declined as the number of F-T cycles increased. The foaming properties and emulsifying properties of CSPI were significantly improved and reached maximum values after three F-T cycles. CSPI undergoing two F-T cycles showed the highest digestibility, maximum polypeptide content, and highest DPPH and ·OH-radical-scavenging activities. The ·OH-radical-scavenging activities and reducing power of the gastrointestinally digested CSPI had the highest value after one F-T cycle. Therefore, it has been demonstrated that F-T treatments could be a residue-free and cost-effective tool for improving mushroom protein functional properties.
探究了冻融（F-T）循环过程中蛋白分离物（CSPI）功能特性和结构的变化。通过对F-T处理后的CSPI进行结构分析，发现其结构有显著改变且蛋白质有序结构含量降低。CSPI的表面疏水性和游离巯基含量先增加后降低。然而，F-T处理后，CSPI的羰基含量持续增加。同样，随着F-T循环次数的增加，CSPI的持水能力（WHC）、持油能力（OHC）和溶解度均下降。CSPI的发泡性能和乳化性能显著改善，并在三个F-T循环后达到最大值。经历两个F-T循环的CSPI表现出最高的消化率、最大的多肽含量以及最高的DPPH和·OH自由基清除活性。经胃肠道消化的CSPI的·OH自由基清除活性和还原能力在一个F-T循环后达到最高值。因此，已证明F-T处理可能是一种无残留且经济高效的改善蘑菇蛋白功能特性的工具。
