南川大树茶红茶初制过程中品质特征分析

以南川大树茶春季1芽2叶为原料,加工传统工夫红茶,研究感官风味及主要品质成分在加工中的变化规律,并以云南大叶种红茶为对照,评价大树茶红茶的适制性及品种特色.结果表明:在南川大树茶红茶加工过程中,水浸出物和茶多酚总量逐渐减少;儿茶素总量大幅减少,除没食子儿茶素没食子酸酯(GCG)在加工中有所增加外,其余7种儿茶素质量分数在加工中均大幅减少.没食子酸(GA)在加工过程中质量分数显著增加.揉捻后,茶黄素总量及茶黄素(TF)、茶黄素-3-没食子酸酯(TF-3-G)、茶黄素-3'-没食子酸酯(TF-3'-G)、茶黄素双没食子酸酯(TFDG) 4个组分质量分数都急剧增加,之后的工序中有增有减,只有TFDG持续积累,且是质量分数最高的组分.茶红素质量分数先增多后减少,而茶褐素在整个加工过程中持续累积.游离氨基酸总量在加工中有所增加,鲜叶含24.11 mg/g,毛茶中达到最大值36.34 mg/g.茶氨酸、天冬氨酸、谷氨酸等质量分数较高,茶氨酸、谷氨酸等随着加工的进行质量分数减少,而天冬氨酸、天冬酰胺、谷氨酰胺等质量分数增加;绝大多数氨基酸经萎凋后质量分数都大幅上升;从发酵结束到烘干的过程中,所有的氨基酸质量分数都有所增加.感官审评表明,整个加工中,发酵80 min时滋味最好,甜醇爽口;综合得分最高的是大树茶红茶,条索紧结,橙黄明亮,甜醇鲜爽,有甜香.相较之下,大树茶汤色不如云南大叶种,但香气更优,整体品质更佳.

Analysis of Quality Characteristics of Camellia nanchuanica During Primary Processing of Black Tea

In this experiment, Camellia nanchuanica with a bud and two leaves, was used as the material to process orthodox black tea. The changes of each major quality component during processing were studied. With C. sinensis var. assamica in Yunnan as the CK, the adaptability of processing and variety characteristics of C. nanchuanica were evaluated. The results showed that during the processing of black tea, the total amount of water extracts and tea polyphenols decreased gradually; the total amount of catechins was greatly reduced; of the 8 catechins studied, the contents of 7 decreased significantly, with the exception of gallocatechin gallate (GCG), and the content of gallic acid(GA)increased significantly. The total amount of theaflavins and the four monomers:theaflavin (TF), theaflavin-3-gallate (TF-3-G), theaflavin-3''-gallat (TF-3''-G) and theaflavin digallat (TFDG) increased sharply after rolling, only TFDG continued to increase in the subsequent processes, and it was always the component with the highest content. The content of thearubigin increased first and then decreased, while the tea brown pigment was steadily accumulated throughout processing. The total amount of free amino acids increased during processing, reaching a maximum of 36.34 mg/g in raw black tea. Theanine, aspartic acid and glutamic acid had higher content. The content of theanine and glutamic were decreased with the processing, Aspartic acid, asparagine, and glutamine increased. Most amino acids increased significantly after withering, and all amino acids increased from the end of fermentation to drying. The sensory evaluation showed that after 80 minutes'' fermentation the taste of the product was the best, sweet and mellow and refreshing. The primary tea of C. nanchuanica had the highest comprehensive score, its knot being tight and the soup being orange and bright in color, sweet and refreshing in taste, and sweet and fragrant in smell. Compared with the black tea, the fermentation time is shorter in 80 minutes, which is beneficial to processing. Comparatively, the soup color of CK was better, but its aroma was not as good as C. nanchuanica black tea, which was better in overall quality.