Improvement of Textural Stability in Cooked Alkaline Noodles by Egg White Powder: Mechanisms of Disulfide Bond Crosslinking and Microstructural Reinforcement.

Abstract

The textural deterioration of yellow alkaline noodles during post-cooking storage poses a challenge in non-ready-to-eat scenarios. Adding exogenous proteins offers a promising solution to enhance the textural stability of cooked noodles, but the optimal ingredient remains unidentified. This study examined the effects of egg white powder (EWP) on the quality of yellow alkaline noodles in comparison to other protein sources, including casein, whey protein, and salted duck egg white powder. A range of EWP additions (0%, 0.5%, 1%, 1.5%, and 2%) was implemented to explore the improvement mechanisms using texture profile analysis, disulfide bond quantification, and noodle microstructure examination. Results showed that noodles with 1.5% EWP retained a hardness of 3.43 N after 60 min, significantly (p < 0.05) exceeding that of the control (3.13 N) and equating to the control's hardness at 30 min. Additionally, noodles with 1.5% EWP demonstrated a 37.21% reduction in adhesion area and an 11.81% decrease in soluble solids compared to the control. Mechanistically, EWP enhanced gluten co-aggregation through thermal gel networks, elevating disulfide bonds by 60.71% and forming dense protein matrices with reduced porosity. These findings indicate EWP's efficacy in optimizing post-cooking textural stability through reinforcement of the gluten network and covalent crosslinking, suggesting that a 1.5% EWP addition is optimal for alkaline noodles.