Structural changes of proteins in fresh noodles during their processing

Abstract

Structural changes of proteins in fresh noodles during mixing, resting, sheeting, and cooking were investigated. The protein structural changes were evaluated by measuring the protein content, molecular weight, thiol and disulfide contents, secondary structure, thermal properties, microstructure, and mean particle size. The protein content was not significantly changed during fresh noodle processing. The wheat protein molecular weight decreased from 66.2 to 22.0 kDa during the cooking process. The disulfide content increased during the mixing and cooking processes. Additionally, the cooking process caused an increase in the number of gluten protein absorption peaks in the FTIR analysis. The secondary structure was mainly composed of β-sheets, and their proportion decreased in the cooking process. Gluten proteins were demonstrated to have high thermal stability with an average denaturation temperature of 84.9°C. There was a significant relationship between the gluten protein properties and fresh noodle processing.