Integration of targeted metabolomics and volatilomics with electronic sensory technologies to reveal key components of Chinese white tea from five major production regions

Compared with Baimudan, Baihaoyinzhen contained higher levels of amino acids, catechins and volatile compounds. • Compared with Baihaoyinzhen, Baimudan contained higher levels of phenolic acids, flavonols and flavones. • Isoschaftoside, salicylic acid and 4-hydroxybenzoic acid were key taste compounds in white tea. • Benzaldehyde, phenethyl alcohol and citral were shared key aroma compounds in white tea. In this study, fresh tea leaves were collected from five major white tea production regions in China and processed into Baihaoyinzhen (silver needle) and Baimudan (white peony). Electronic sensory technologies were used to characterize electronic sensory response profiles, while UHPLC-QqQ-MS and HS-SPME-GC–MS were used to quantify 18 amino acids, 52 polyphenolic compounds, and 64 volatile compounds. Overall, Baihaoyinzhen contained higher levels of volatile compounds, amino acids, and catechins than Baimudan. In contrast, Baimudan exhibited higher total contents of phenolic acids, flavonols and flavones than Baihaoyinzhen. Glu and Phe were linked to sweetness and astringency, respectively, whereas EGCG was consistently associated with astringency. Isoschaftoside, salicylic acid and 4-hydroxybenzoic acid were identified as key compounds associated with taste differences. For aroma, benzaldehyde, phenethyl alcohol and citral were identified as shared key aroma compounds in Baihaoyinzhen and Baimudan. These findings provide a multidimensional chemical basis for quality differentiation among Chinese white teas. Download: Download high-res image (180KB) Download: Download full-size image