State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, Jiangxi 330047, China.
State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, Jiangxi 330047, China; National R&D Center for Freshwater Fish Processing, Jiangxi Normal University, Nanchang, Jiangxi, 330022, China; Engineering Research Center for Freshwater Fish High-value Utilization of Jiangxi Province, Jiangxi Normal University, Nanchang, Jiangxi 330022, China.
J Dairy Sci. 2020 Apr;103(4):2993-3001. doi: 10.3168/jds.2019-17322. Epub 2020 Feb 11.
Bovine β-lactoglobulin (β-LG) is the major allergen in milk powder. The IgG/IgE binding capacity and structural characteristics of β-LG after spray drying in the presence or absence of α-lactose at 120 and 180°C were investigated by ELISA and mass spectrometry. At a drying temperature of 120°C, no change was found in the IgG/IgE binding capacity of β-LG and no change was observed in free amino group content, fluorescence intensity, or detectable glycation. At a drying temperature of 180°C, aggregation of β-LG occurred, leading to a decrease in the IgG/IgE binding capacity. When α-lactose was also present, 7 lysine side-chains in β-LG were modified by glycation and the IgG/IgE binding capacity was further decreased. Therefore, the glycation and structural changes in β-LG were responsible for the reduction in the IgG/IgE binding capacity during high temperature (180°C) spray drying.
牛β-乳球蛋白（β-LG）是奶粉中的主要过敏原。通过 ELISA 和质谱法研究了在 120 和 180°C 下存在或不存在α-乳糖时喷雾干燥对β-LG 的 IgG/IgE 结合能力和结构特性的影响。在干燥温度为 120°C 时，β-LG 的 IgG/IgE 结合能力没有变化，游离氨基含量、荧光强度或可检测的糖基化也没有变化。在干燥温度为 180°C 时，β-LG 发生聚集，导致 IgG/IgE 结合能力下降。当α-乳糖也存在时，β-LG 的 7 个赖氨酸侧链发生糖基化修饰，IgG/IgE 结合能力进一步降低。因此，β-LG 的糖基化和结构变化是导致高温（180°C）喷雾干燥过程中 IgG/IgE 结合能力降低的原因。
