Abstract:
This study aimed to investigate the quality characteristics and chemical composition of Baimudan white teas processed from different tea cultivars in the Yibin tea region, the quantitative descriptive analysis, biochemical analysis, high-performance liquid chromatography (HPLC), and headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME-GC-MS) to analyze the sensory quality and flavor compounds of white teas processed from eight cultivars, ‘Zhongcha 302’ (ZC302), ‘Fuding Dabaicha’ (FDDB), ‘Wuniuzao’ (WNZ), ‘Chuancha 2
#’ (CC2), ‘Fuxuan 9
#’ (FX9), ‘Mingshan 131’ (MS131), ‘Zhongcha 108’ (ZC108), and ‘Huangjinya’ (HJY). The results indicated that all eight tea varieties exhibited favorable sensory qualities, though significant differences existed among them. FDDB, ZC302, and CC2 presented a distinct tip aroma or floral fragrance, fresh and sweet taste, and soft, yellow-green infused leaves, achieving higher overall sensory scores. In contrast, WNZ and FX9 exhibited a clean and refreshing with noticeable grassy odour, along with approach fresh and mellow taste accompanied by grass or sour off-flavors, resulting in relatively lower sensory scores. HJY showed the highest free amino acid content and lowest phenol-ammonia ratio, yet it also had the lowest water extractives content. FDDB, ZC302, and CC2 displayed higher levels of free amino acids, theanine and sweet-tasting amino acids, while lower contents of tea polyphenols, total catechins, ester-type catechins, and bitterness-astringency index. Conversely, MS131 and FX9 had significantly higher levels of tea polyphenols, total catechins, ester-type catechins, and exhibited the highest bitterness-astringency index among all cultivars. Multivariate statistical analysis identified nine differential taste-related compounds, namely epigallocatechin gallate, caffeine, epigallocatechin, catechin, gallocatechin, tea polyphenols, theanine, water extractives, and epicatechin gallate. Furthermore, 28 key aroma compounds were identified in the three superior tea varieties. Among these, linalool, geraniol, and phenylacetaldehyde were more abundant in CC2, contributing to its prominent floral aroma, while green-note compounds such as (Z)-3-hexenol and hexanal occurred at relatively lower levels in FDDB and ZC302. In conclusion, tea varieties significantly influenced the quality characteristics of white tea. FDDB, ZC302, and CC2 demonstrated superior suitability for white tea production, providing a scientific basis for tea varieties selection and quality enhancement of Yibin white tea.