Effects of steam processing conditions on the aroma and "dryness-like" effect of <i>Citri Sarcodactylis fructus</i>(FoShou tea).

Abstract

This study systematically explored the impact of steaming processing on <i>Citri Sarcodactylis Fructus</i>, focusing on changes in aroma, "dryness-like" properties, and the underlying chemical mechanisms. By employing HS-GC-MS, UHPLC-MS, electronic nose analysis, and animal experiments, we found that steaming triggered distinct changes in flavor substances: fresh, citrus-like volatiles diminished, while woody and bitter compounds increased, leading to a more intense aroma. It also drove the transformation of active components: flavonoid glycosides were converted to aglycones, with coumarins and limonoids were rearranged. These changes alleviated "dryness-like" effects: steamed CSF reduced rat water intake and blood viscosity (<i>p</i> < 0.05), normalized the aquaporins expression. Molecular and cellular assays linked this to stronger aglycone-AQP binding and weaker glycoside-induced AQP5 inhibition, which directly linked steaming to reduced dryness. This research clarified how steaming enhances aroma complexity and reduces "dryness-like" properties through targeted chemical transformations, providing a scientific basis for optimizing CSF processing via steaming.