Determination of physical and chemical properties of kombucha teas prepared with different herbal teas

Abstract In this research, kombucha tea was prepared using 5 different tea extracts and physicochemical and sensory analyses were made. The tea extracts used are black tea, green tea, sage, linden and mint, respectively. The prepared tea samples were subjected to fermentation for 14 days. In tea samples, pH, electrical conductivity, water-soluble solid and phenolic components were analyzed before and after fermentation. pH values decreased by an average of 63% in all tea samples after fermentation. The electrical conductivity increased in black tea, green tea and mint tea, while sage and linden decreased. Brix values decreased in all tea samples, the most decrease was in black tea. Total amount of phenolic contents of kombucha tea samples decreased excluding mint tea sample. As a result of sensory analysis of tea samples, mint tea got the highest score. As a result of the research, it has been determined that the kombucha tea, which is usually made with black and green tea, can be prepared with teas of different flavors and its consumption can be increased.摘要 本研究采用5种不同茶浸提液制备康普茶（kombucha tea），并开展理化与感官分析。所用茶浸提液依次为红茶、绿茶、鼠尾草、椴树及薄荷的浸提液。将制备得到的茶样品进行14天发酵处理。分别于发酵前后，对各茶样品的pH值、电导率、水溶性固形物及酚类成分进行检测分析。结果显示，发酵后所有茶样品的pH值平均下降63%；红茶、绿茶与薄荷茶的电导率有所升高，鼠尾草茶与椴树茶的电导率则出现下降；所有茶样品的白利糖度（Brix）值均有所降低，其中降幅最大的为红茶样品；除薄荷茶样品外，其余康普茶样品的总酚含量均出现减少。经感官评价分析，薄荷茶样品获得最高评分。本研究结果表明，常规以红茶和绿茶为原料制备的康普茶，可采用不同风味的茶类进行制备，从而提升其消费量。