Effects and Mechanisms of Fermentation by Nonconventional Yeast Kazachstania servazzii CDLB-YE05 on the Flavor and Texture of Fresh Noodles.

Noodles are a traditional staple food in Asia, and fermentation has gained increasing attention for improving their quality. This study investigated the effects of the nonconventional yeast Kazachstania servazzii CDLB-YE05 on the quality of fresh noodles, using unfermented fresh noodles (CK) and noodles fermented with commercial Saccharomyces cerevisiae (SC) as controls. Sugar metabolism, volatile flavor, texture, and the protein-starch network were systematically evaluated. Results showed that YE05 maintained high amylase activities, promoted maltose accumulation, and preserved higher levels of fructose and sucrose. In terms of flavor, YE05 fermentation increased the odor activity values of key aroma compounds, including ethyl acetate, isoamyl alcohol, and 2,3-butanedione, whereas cooked YE05 noodles retained a characteristic aroma profile dominated by aldehydes, ketones, and furan compounds. Regarding texture, YE05 fermentation increased the content of α-helix and post-cooking disulfide bond content, altered starch pasting properties by reducing peak viscosity and breakdown, increased gelatinization enthalpy, and enhanced starch gel strength, leading to the formation of a dense and uniform honeycomb-like microstructure, which subsequently increased noodle springiness by 32.83% and reduced cooking loss by 24.77% compared to the control. These findings reveal that YE05 enhances fermented noodle quality by coordinately regulating sugar metabolism, protein network reorganization, and starch structure, providing a mechanistic basis for the development of superior products.