Effect of Different Pretreatment of Raw Materials on Flavor Quality of Zhaotong Soybean Paste

In order to explore the effect of different pretreatment processes of raw materials (soybean) on the flavor of Zhaotong soybean paste, the amino acids and volatile compounds of Zhaotong soybean paste were analyzed by steaming at 115 ℃ for 10 min (S-10), 15 min (S-15), 20 min (S-20) and 25 min (S-25), and frying at 180 ℃ for 5 min (F-5) and 10 min (F-10). The results showed that there were significant differences in amino acids and volatile components of Zhaotong soybean paste pretreated with different raw materials. The score of Zhaotong soybean paste treated with F-10 was the highest, 89 points, and the total amount of amino acids was the highest in the S-15 treatment group, 29.314 mg/g, included 14.196 mg/g of essential amino acids and 15.082 mg/g of flavor amino acids. The second was the F-10 treatment group, the total amount of amino acids was 28.570 mg/g, of which the content of essential amino acids was 13.047 mg/g and the content of flavor amino acids was 17.949 mg/g, and the content of fresh amino acids in the F-10 treatment group was 15.067 mg/g, which was significantly higher than that in other treatment groups. Different pretreated Zhaotong soybean paste also showed great differences in the content and distribution of volatile components. The volatile components in Zhaotong sauce were mainly composed of olefins, alcohols and esters. The relative content of alcohols in cooking group was higher, up to 17.29% in S-10 group. The relative content of esters in frying group was higher, and phenols were produced. The highest relative content of esters was 12.74% in F-10 group, which was 3.72%~6.91% higher than that in other groups. A total of 12 common components were detected in all samples, of which anethole contributed the most to the flavor, accounting for more than 50%, followed by (+) terpene diene γ-terpinene, eucalyptus oleanol, n-pentadecane, linalool, linalyl acetate, terpinyl acetate α-terpineol, 4-methoxystyrene, anethole, phenylethanol and p-isopropyl benzyl alcohol. These substances mainly present fragrance, licorice, fruit and flower fragrance, which form the common basic flavor components of Zhaotong soybean paste. This paper compared the flavor quality of Zhaotong soybean paste pretreated with different raw materials, so as to provide reference for improving the development of local soybean sauce industry and popularizing local plateau characteristic agricultural products.