N ε-(carboxymethyl)lysine formation from the Maillard reaction of casein and different reducing sugars

Food Sci Biotechnol. 2019 Oct 15;29(4):487-491. doi: 10.1007/s10068-019-00689-3. eCollection 2020 Apr.

Abstract

Dietary advanced glycation end products (AGEs) are involved in the pathogenesis of diabetic complications, atherosclerosis, and kidney disease. Formation of N ε-(carboxymethyl)lysine (CML), a well-known AGEs, was evaluated from the reaction of casein from bovine milk with different reducing sugars (glucose, tagatose, and xylose) at various sugar concentrations and heating temperatures (75 and 120 °C) used in food processing to determine the best sweetener to be used in dairy products. The concentration of CML was measured using an enzyme-linked immunosorbent assay. Additionally, SDS-PAGE was carried out to observe the changes in the molecular weight of casein. The results reveal that tagatose leads to a lower CML concentration at 75 °C than glucose or xylose, whereas no significant differences are observed at 120 °C. We conclude that it would be more appropriate to use tagatose rather than glucose or xylose as a sweetener, considering the AGEs contents in heat-treated dairy products.

Keywords: Advanced glycation end products; Casein; Maillard reaction; Nε-(Carboxymethyl)lysine; Reducing sugar.