Abstract:
To investigate the suitability of different tea plant strains bred from local populations in Guangxi for green tea production, fresh leaves of nine new tea strains were used as raw materials to process green tea, with Fuyun No. 6 as a control. The differences in sensory quality, major biochemical components, and aroma components were analyzed. Results showed that all of the nine new tea strains produced green tea with overall sensory evaluation scores above class B. Among them, strains H012, 2018-11, 2015-14, and Pin-2 achieved class A scores, outperforming the control sample. Regarding taste profiles, the respective features were: brisk and mellow, aromatic with robust body, fresh and mellow, and floral with intense, well-rounded flavor. Aroma characteristics for these strains were identified as rich tender chestnut, tender with floral overtone, strong and persistent floral, and pronounced floral notes. Biochemical analyses revealed significant differences in major constituents and their contents across green teas from the nine new strains. Water extract, flavonoids, tea polyphenols and total catechin contents were also markedly higher in strains 2015-11, 2018-10, 2018-18, and Pin-2 relative to the control (
P<0.05). Free amino acid content was elevated in strains H012, 2018-10, 2018-11, and 2015-14. A lower phenol-to-amino acid ratio was observed in strains H012, 2018-11, 2015-14, and 2018-10, while Pin-2 exhibited a higher ratio. The correlation analysis showed that the taste score was positively correlated with the content of free amino acids (
P<0.01), and negatively correlated with the content of tea polyphenols and phenol-amine ratio. This suggested an alignment between biochemical composition and sensory assessment. Aroma component analysis detected 193 volatile compounds in green teas from the different strains and the control, primarily comprising alcohols, hydrocarbons, nitrogenous compounds, aldehydes, esters, and ketones. Among these classes, alcohols represented the highest relative abundance. A PLS-DA model constructed from aroma profile data effectively distinguished among the ten green tea samples. Incorporating relative odor activity values, seven key differential aroma constituents were identified. In summary, all nine new tea strains demonstrate suitability for green tea manufacturing. Among these, H012, 2018-11, 2015-14, and Pin-2 exhibit notable advantages for the development of premium specialty green teas, each with individual characteristics. This research provides a scientific foundation for the utilization of
Camellia sinensis germplasm resources in Guangxi and the selection of high-quality raw materials for distinguished green tea production.