Response Surface Optimization of Steamed Green Cake Tea Decocting Method

Fresh one-bud, two-leaf tea from the local small-leaf population in Sichuan Province was used to make steamed green cake tea according to the traditional process recorded in Lu Yu’s The Classic of Tea, and the decoction method was employed to prepare the tea soup. The effects of tea dosage, salt injection and salinity of water on the main taste components of the tea soup were analyzed. The results showed that the tea dosage had significant influenced the extraction of free amino acids, tea polyphenols, caffeine and water-soluble compounds. The salinity of water and the interaction between the salinity of water and salt injection had a significant effect on free amino acids. A multiple regression equation model with sensory scores of tea soup as response value was developed. The optimal brewing conditions for steamed green cake tea decocting were: tea dosage 3 g (tea-water ratio 1:200), salt dosage 0.7 g and water salinity (TDS) 0 mg/L. Under these conditions, the tea liquor had a mellow, sweet taste with high balance, a fresh, pleasant aroma, and a bright apricot-colored appearance.