Thermal Degradation of Thaumatin at Low pH and Its Prevention Using Alkyl Gallates.
Thermal Degradation of Thaumatin at Low pH and Its Prevention Using Alkyl Gallates.
复制标题
低 pH 条件下索马甜的热降解及其使用烷基没食子酸酯的预防。
DOI：
10.1016/j.foodhyd.2023.108544
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发表时间：
2023
影响因子：
10.7
通讯作者：
Abbaspourrad,Alireza
中科院分区：
文献类型：
--
作者：
Pomon,Benjamin;Zhao,Yu;Lai,AlexL;Lin,Tiantian;Freed,JackH;Abbaspourrad,Alireza
Thaumatin是一种从凯特菲植物中提取的有效甜味蛋白质，正在成为合成非营养甜味剂和风味增强剂的天然替代品。作为一种食品添加剂，其在热加工过程中在食品基质中的稳定性是食品工业非常关注的问题。当在中性或碱性条件下加热时，由于巯基催化的二硫键交换导致蛋白质聚集，索马汀失去了其甜度。在较低的pH下，虽然索马汀在加热后也会失去甜度，但速度较慢，对甜度损失表现出更强的抵抗力。SDS-PAGE分析表明，在酸性pH条件下加热，索马菌素碎裂成多个小片段。使用BEMPO-3，一种亲脂的自旋陷阱，我们能够在加热过程中检测到蛋白质疏水区域中自由基的存在。蛋白质氧化的副产物-蛋白质羰基含量也随着加热而增加，这为蛋白质被自由基途径切割提供了额外的证据。没食子酸己酯在加热过程中成功地抑制了索马汀的自由基生成和蛋白质羰基的生成。
Thaumatin, a potent sweet tasting protein extracted from the Katemfe Plant, is emerging as a natural alternative to synthetic non-nutritive sweeteners and flavor enhancer. As a food additive, its stability within the food matrix during thermal processing is of great interest to the food industry. When heated under neutral or basic conditions, thaumatin was found to lose its sweetness due to protein aggregation caused by sulfhydryl catalyzed disulfide bond interchange. At lower pH, while thaumatin was also found to lose sweetness after heating, it does so at a slower rate and shows more resistance to sweetness loss. SDS-PAGE indicated that thaumatin fragmented into multiple smaller pieces under heating in acidic pH. Using BEMPO-3, a lipophilic spin trap, we were able to detect the presence of a free-radical within the hydrophobic region of the protein during heating. Protein carbonyl content, a byproduct of protein oxidation, also increased upon heating, providing additional evidence for protein cleavage by a radical pathway. Hexyl gallate successfully inhibited the radical generation as well as protein carbonyl formation of thaumatin during heating.