Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro, Tokyo, 153-8902, Japan.
R&D Division, Institute of Technology Solution, Kewpie Corporation, Sengawa Kewport, 2-5-7 Sengawa, Chofu, Tokyo, 182-0002, Japan.
Sci Rep. 2022 Jun 2;12(1):9218. doi: 10.1038/s41598-022-12885-z.
Hen eggs are rich in proteins and are an important source of protein for humans. Pasteurized frozen whole hen eggs are widely used in cooking and confectionery and can be stored for long periods. However, processed eggs differ from raw eggs in properties such as viscosity, foaming ability, and thermal aggregation. To develop pasteurized frozen whole egg products with properties similar to those of unpasteurized whole eggs, it is necessary to establish a method that can differentiate between the two egg types with respect to the structures of their proteins. In this study, size-exclusion chromatography (SEC) and SEC coupled with small-angle X-ray scattering (SEC-SAXS) were successfully used to differentiate between the proteins in unpasteurized and pasteurized frozen whole eggs. We found that proteins in the plasma fraction of egg yolk, especially apovitellenins I and II, formed large aggregates in the pasteurized eggs, indicating that their structures are sensitive to temperature changes during pasteurization, freezing, and thawing. The results suggest that SEC and SEC-SAXS can be used to differentiate between unpasteurized and pasteurized frozen whole eggs. Additionally, they may be useful in determining molecular sizes and shapes of multiple components in various complex biological systems such as whole eggs.
鸡蛋富含蛋白质，是人类获取蛋白质的重要来源。巴氏杀菌冷冻全蛋液广泛应用于烹饪和糖果制作中，可长期储存。然而，加工蛋与生蛋在粘度、起泡能力和热聚集等性质上存在差异。为了开发出具有类似未巴氏杀菌全蛋液性质的巴氏杀菌冷冻全蛋液产品，有必要建立一种能够区分两种蛋类型的方法，以区分其蛋白质结构。在这项研究中，成功地使用尺寸排阻色谱（SEC）和 SEC 与小角 X 射线散射（SEC-SAXS）来区分未巴氏杀菌和巴氏杀菌冷冻全蛋液中的蛋白质。我们发现蛋黄血浆部分的蛋白质，特别是卵黄高磷蛋白 I 和 II，在巴氏杀菌蛋中形成大的聚集体，这表明它们的结构对巴氏杀菌、冷冻和解冻过程中的温度变化很敏感。结果表明，SEC 和 SEC-SAXS 可用于区分未巴氏杀菌和巴氏杀菌冷冻全蛋液。此外，它们可能有助于确定各种复杂生物系统（如全蛋）中多种成分的分子量和形状。
