State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, China.
Hunan Engineering & Technology Research Center for Food Flavors and Flavorings, Jinshi, China.
J Sci Food Agric. 2023 Feb;103(3):1261-1272. doi: 10.1002/jsfa.12220. Epub 2022 Sep 28.
Glycosylation is an effective method to modify protein. However, there is a lack of research on the property changes of glycosylated protein during storage. In the present study, the changes in the physicochemical, functional, and structural properties of xylo-oligosaccharide (XOS) glycosylated egg white powder (EWP) (XOS-EWP conjugates) prepared with different glycosylation conditions (XOS/EWP ratio and reaction time) were investigated when stored at 25 °C and 60% relative humidity.
In the 12 weeks of storage, the degree of grafting, browning, and the formation of Maillard reaction products of XOS-EWP conjugates increased. The increase in XOS/EWP ratio and reaction time led to an increase in protein aggregation, though a decrease in solubility, due to increased degree of glycosylation and structural changes. Furthermore, improved gel hardness of XOS-EWP conjugates deteriorated, while improved emulsification ability was kept stable during storage. For the sample with a lower XOS/EWP ratio and reaction time, the gel hardness and emulsifying properties underwent little or no deterioration even improving during storage. The results could be attributed to the limited degree of glycosylation, further unfolding of the protein structure, increased surface hydrophobicity of protein, and improved thermal characteristics.
During storage, the Maillard reaction would continue to occur in the glycosylated EWP, further affecting the performance of modified EWP. Modified EWP prepared under different glycosylation conditions performed differently during storage. Modified EWP with a larger XOS/EWP ratio and reaction time meant it was harder to maintain good performance. Modified EWP with a smaller XOS/EWP ratio and reaction time changed significantly to better performances. © 2022 Society of Chemical Industry.
糖基化是一种有效的修饰蛋白质的方法。然而，在储存过程中，糖基化蛋白质的性质变化研究还很缺乏。在本研究中，考察了不同糖基化条件（XOS/EWP 比和反应时间）制备的木寡糖（XOS）糖基化蛋清粉（EWP）（XOS-EWP 缀合物）在 25°C 和 60%相对湿度下储存时理化性质、功能和结构性质的变化。
在 12 周的储存期内，XOS-EWP 缀合物的接枝度、褐变和美拉德反应产物的形成增加。XOS/EWP 比和反应时间的增加导致蛋白质聚集增加，尽管溶解度降低，这是由于糖基化程度增加和结构变化所致。此外，在储存过程中，XOS-EWP 缀合物的凝胶硬度提高，而乳化能力保持稳定。对于 XOS/EWP 比和反应时间较低的样品，即使在储存过程中，凝胶硬度和乳化性能也没有或几乎没有恶化，反而有所提高。这可能归因于糖基化程度有限、蛋白质结构进一步展开、蛋白质表面疏水性增加以及热特性得到改善。
在储存过程中，糖基化 EWP 中的美拉德反应会继续发生，进一步影响改性 EWP 的性能。不同糖基化条件制备的改性 EWP 在储存过程中表现不同。XOS/EWP 比和反应时间较大的改性 EWP 更难保持良好的性能。XOS/EWP 比和反应时间较小的改性 EWP 变化显著，性能更好。© 2022 英国化学学会。
