Study on the Quality Difference of Yun Kang 10 Anaerobic Processed White Tea in Different Seasons

In this study, the fresh leaves of Yun kang 10 with one bud and two or three leaves in spring, summer and autumn were used as raw materials. After anaerobic treatment, white tea was processed by the same process. The quality differences of white tea made from raw materials in three seasons after anaerobic treatment were explored by sensory evaluation, physical and chemical composition determination and UHPLC-MS/MS high-throughput detection technology to detect the content of amino acid components. The results showed that there were significant differences in the quality of white tea in the three seasons. The dry tea of white tea in spring was bright green in color. The aroma was strong, lasting, high and intensive, and had a variety of aroma types such as flowery, honey, tip aroma, medicinal and the fragrance of unique process. The taste was strong, fresh, sweet and brisk. The color of tea soup was bright yellow. Infused leaf was soft and bright. The quality of sensory was the best. The contents of amino acids, soluble sugar, caffeine, water extract and flavonoids of white tea were the highest in spring, and the content of tea polyphenols white tea was the highest in summer. A total of twenty amino acids were detected, of which 18 amino acids were significantly different (P<0.05). The highest content of γ-aminobutyric acid (GABA) of white tea was 1.22 mg/g in spring. The content of 8 amino acid components was the highest in spring white tea. The content of three amino acid components was the highest in summer white tea. The content of six amino acid components was the highest in autumn white tea. Through PCA principal component analysis and differential compounds screening, a total of fifteen differential compounds were obtained to distinguish the three seasons of white tea. Based on the results of sensory evaluation, physical and chemical components and amino acid components, white tea in spring was significantly different from white tea in summer and autumn, and the overall quality of white tea in spring was better.