Guangxi Old Tree Black Tea uses fresh leaves of old tea trees (more than 100 years) as ingredients. It uses a special tea-making method of Gongfu black tea technique. Gongfu black tea technique refers to using elaborated technique and taking losts of manpower and efforts to make black tea. As a result, black tea made through this technique is very unique. Compared with other tea, old tree tea contains more water extract substances, tea polyphenols, amino acids, etc. The taste of old tree tea is sweeter and smoother. Old tree tea also has higher brew resistance. According to the experts, the special leaves of old tree tea has an obvious effect of lowering blood glucose.