Simulated accelerated aging controlled by temperature and humidity for regulating the quality of Citri grandis fructus immaturus.

Citri grandis fructus immaturus (CGFI) is well-known for its dual usage in medicine and food. After aging, it wound bring about the transformation and enrichment of its medicinal components in CGFI. The content of active ingredients including flavonoids (such as naringin and rhoifolin) would increase, making its medicinal properties milder and its taste more mellow. However the transformation of active components in CGFI proceeds slowly under natural aging conditions, rendering conventional aging methods not only time-consuming but also inefficient. To address this issue, the present study employed an accelerated aging simulation under controlled temperature and humidity conditions to comprehensively evaluate changes in the quality attributes of CGFI. Three experimental groups were established for verification. CGFI were periodically assessed for visual appearance, moisture content, infusion color, as well as the contents of total flavonoids, naringin, and rhoifolin. Besides, non-targeted metabolomics analysis was conducted to investigate alterations in metabolite profiles and related pathway enrichment. The results demonstrated that the constant group (35 °C, 75% RH) treatment exhibited favorable aging effect, significantly increased the flavonoid compounds and enhanced antioxidant metabolites accumulation, due to the fact that the stability of flavonoids and tangerine glycosides was highly dependent on the storage environment. The research provides a theoretical foundation and methodological framework for optimizing the aging process of CGFI. This study is expected to provide new insight into the simulated accelerated aging-related evolution of active ingredient, as well as the material basis and sensory features of CGFI, thereby offering a candidate chemical basis and theoretical reference for CGFI quality evaluation and targeted regulation.