## 3 Results and Discussion
### Analysis of Main Biochemical Components  
The major biochemical components such as catechins, caffeine, tea polyphenols, and amino acids in teas are greatly affected by harvest seasons and tea cultivars [23]. As shown in Table 2, comparing SH-S to SH-A, the contents of EC, ECG, polyphenols, and caffeine in SH-S were significantly lower (\(p<0.05\)) than SH-A, and the contents of EGC, water extracts, soluble sugar and free amino acids in SH-S were significantly higher (\(p<0.05\)) than SH-A. However, there was no significant difference in EGCG between SH-S and SH-A. Comparing FD-S to FD-A, the contents of EC, ECG, caffeine, and polyphenols in FD-S were significantly lower (\(p<0.05\)) than FD-A, and the contents of EGC, EGCG, free amino acids, and soluble sugar in FD-S were significantly higher (\(p<0.05\)) than FD-A. Conversely, there was no significant difference in water extract contents between FD-S and FD-A (Table 2). The biochemical components of the two cultivars exhibited consistent trends in spring and autumn tea, with significant differences observed solely in the levels of EGCG and water extract contents. The results of this study were consistent with the seasonal variation trend in Fujian white tea [4; 24]. According to previous studies, the biochemical components of teas are greatly affected by harvest seasons [25; 26; 27]. Light intensity and temperature can synergistically regulate catechin synthesis [28]. The temperature in spring and autumn is not much different, and it is guessed that the light intensity is the main reason for the change in components. The observed biochemical differences in compositional disparities between spring and autumn tea samples in this study, processed under comparable temperature conditions, are hypothesized to result primarily from differential light intensity exposure during cultivation.  
\begin{tabular}{c} SH-S: Sanhua1951, spring; FD-S: Fudingdabai, spring; SH-A: Sanhua1951, autumn; FD-A: Fudingdabai, autumn. Different lowercase letters in the same column indicate a significant difference among white teas (\(p<0.05\)).  
\end{table}
Table 1: Sensory assessment of ‘Sanhua1951’ and ‘Fudingdabai’ from different seasons.  
It was worth noting that ECG content in SH-A was 36 times higher than that of SH-S, and that ECG content in FD-A was 68 times higher than that of FD-S in this study. ECG is the key component in tea soup, which has the lowest bittermess detection threshold and the most intense taste among catechins [29], and the content was affected by factors such as tea cultivars, growing environment, processing, and so on [30; 31]. In addition, catechins, major polyphenols in tea, are known for contributing to the astringent flavor of the tea broth [32]. Therefore, spring teas (SH-S, FD-S) were less astringent than autumn teas (SH-A, FD-A). The presence of astringency was also confirmed through a sensory evaluation of the SH-A sample (Table 1), which is consistent with the observed chemical profile. Free amino acids, especially theanine, are responsible for the tea's umami taste, and the taste intensity increases with the amino acid concentration [33]. In this study, spring teas (SH-S, FD-S) had higher (\(p\) < 0.05) amino acid and lower (\(p\) < 0.05) polyphenol contents than autumn teas (SH-A, FD-A) (Table 2).