Abstract:Objective To determine the optimal storage period for bread.Methods Changes in the sensory characteristics, physicochemical properties, and volatile flavor substances of bread are analyzed during storage periods of 0, 1, 2, 3, 4, 5, 6, and 7 days.Results No noticeable mold was observed during storage, but when the storage time exceeded 5 days, a slight off-flavor began to appear. Throughout the storage period, the pH value and total microbial count of the bread increased, while moisture content, water activity, and specific volume decreased. A total of 48 compounds were detected in the flavor profile, primarily alcohols and acids. Principal component analysis (PCA) revealed significant differences in flavor between breads stored for different durations. When storage time exceeded 5 days, the flavor significantly differed from that of the fresh bread (0 days). Partial Least Squares Discriminant Analysis (PLS-DA) identified 10 substances with VIP values >1 (e.g., isobutyric acid and isobutanol-D), which played a key role in distinguishing the freshness of the bread.Conclusion Bread quality significantly deteriorated over the 7-day storage period, especially after 5 days, when both flavor and sensory quality showed a marked decline.