Cultivar-Specific Chemical Profiles and Processing-Related Changes in Lushan Yunwu Green Tea

Tea cultivar and processing strongly influence the chemical composition and sensory quality of Lushan Yunwu green tea (LYGT). Despite its economic and cultural significance, dynamic changes of key metabolites across cultivars and processing remain unclear. Five cultivars were analyzed, identifying 28 non-volatile and 12 volatile differential metabolites. Fresh leaves showed cultivar-dependent variations in flavonoids, catechins, phenolic acids, amino acids, and aroma compounds dominated by alcohols and terpenoids. During processing, metabolic changes were most pronounced at the fixation stage, with non-volatile compounds undergoing enzymatic transformation, thermal degradation, and oxidation, while volatile compounds decreased, reducing grassy notes and forming characteristic high-temperature aromas. These findings clarify the chemical basis of cultivar-specific sensory traits and provide guidance for cultivar selection and process optimization.