Effects of electron beam irradiation pretreatment on the physicochemical components, sensory properties, and aroma compounds of mulberry leaf tea fermented with Eurotium cristatum

Mulberry leaf tea is favored for flavor and health benefits. However, the market products sometimes exhibit astringency, insufficient aroma, and low nutritional content due to limitations in fermentation conditions. The study investigated the effects of electron beam irradiation (EBI) on the chemical composition, sensory quality, and aroma of fermented mulberry leaf tea. Different doses of EBI were applied, and the microstructure was observed using SEM and TEM. Results showed a dose-dependent increase in Eurotium cristatum , with a significant rise at 1.2 kGy. Sensory evaluation revealed that 1.2 kGy irradiation improved color, aroma, and taste, with the highest score (8.81) in this group. Analysis of aroma compounds identified 277 upregulated compounds in the irradiated group, enhancing sweet, fruity, and mushroom flavors. 1-octen-3-ol was the main contributor to the aroma. In conclusion, EBI at 1.2 kGy effectively improved mulberry leaf tea quality, demonstrating its potential as a novel processing technology.