Effect of pH treatment on egg white protein digestion and the peptidomics of their in vitro digests

Ting Zhang; Tingting Chen; Hongyu Jiang; Min Zhang; Ping Gong; Jingbo Liu; Xuanting Liu

doi:10.1016/j.foodres.2023.113327

Effect of pH treatment on egg white protein digestion and the peptidomics of their in vitro digests

Food Res Int. 2023 Nov;173(Pt 1):113327. doi: 10.1016/j.foodres.2023.113327. Epub 2023 Jul 26.

Authors

Ting Zhang¹, Tingting Chen², Hongyu Jiang³, Min Zhang⁴, Ping Gong⁵, Jingbo Liu⁶, Xuanting Liu⁷

Affiliations

¹ Jilin Provincial Key Laboratory of Nutrition and Functional Food, College of Food Science and Engineering, Jilin University, Changchun 130062, China. Electronic address: tingzhang@jlu.edu.cn.
² Jilin Provincial Key Laboratory of Nutrition and Functional Food, College of Food Science and Engineering, Jilin University, Changchun 130062, China. Electronic address: Tingtc0508@163.com.
³ Jilin Provincial Key Laboratory of Nutrition and Functional Food, College of Food Science and Engineering, Jilin University, Changchun 130062, China. Electronic address: jhystudy@163.com.
⁴ Jilin Provincial Key Laboratory of Nutrition and Functional Food, College of Food Science and Engineering, Jilin University, Changchun 130062, China. Electronic address: zmyfwzhangmin@163.com.
⁵ Jilin Provincial Key Laboratory of Nutrition and Functional Food, College of Food Science and Engineering, Jilin University, Changchun 130062, China. Electronic address: ping19962020@163.com.
⁶ Jilin Provincial Key Laboratory of Nutrition and Functional Food, College of Food Science and Engineering, Jilin University, Changchun 130062, China. Electronic address: ljb168@sohu.com.
⁷ Jilin Provincial Key Laboratory of Nutrition and Functional Food, College of Food Science and Engineering, Jilin University, Changchun 130062, China. Electronic address: lxt920523@163.com.

PMID: 37803637
DOI: 10.1016/j.foodres.2023.113327

Abstract

The pH treatment significantly enhanced the functional properties of egg white protein (EWP), but little is known about the relationship between pH treatment and in vitro digestion of EWP. In this paper, we explored the effect of pH treatment (pH 2, pH 2-7, pH 12 and pH 12-7) on the digestibility of egg white protein and peptide profiling using the digestion kinetics and peptidomics methods, separately. The results implied that all pH treatment reduced the protein digestibility in gastric phase, while alkaline pH (pH 12 and pH 12-7) showed greater digestion level and more gastric peptides, and more importantly, produced a greater amount of potentially bioactive peptides than acid treated samples. Besides, the least number of potentially bioactive peptides was obtained at pH 2, but this could be improved by adjusting pH 2 back to 7. Notably, the unique bioactive peptides induced by pH were mainly relevant to DPP IV inhibitor. These differences of digestibility and peptide profiling might be attributed to the change of protein structure and the formation of molten sphere, altering cleavage sites of digestive enzymes. This work would give an enlightening insight into the digestive and nutritional characteristics of the pH-induced EWP to expand their application in the field of food and healthcare.

Keywords: Digestion kinetics; Egg white protein (EWP); Peptidomics; Structure characteristics; pH treatment.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Egg Proteins* / chemistry
Hydrogen-Ion Concentration
Peptides* / chemistry
Proteolysis

Substances

Egg Proteins
Peptides