Abstract: Taking tobacco bud as raw material and the content of water-soluble amino acids and water-soluble reducing sugar as indexes, the enzymolysis temperature, pH, enzyme dosage and enzymolysis time were optimized by single factor test. Then, Maillard reaction at different temperatures were carried out on the enzymolysis products obtained under the optimized conditions. The volatile components were extracted by simultaneous distillation extraction and analyzed by GC-MS. The results showed that the optimum conditions for enzymatic hydrolysis were enzymolysis temperature 50 ℃, pH 7, enzymolysis time 5 h and enzyme dosage 1.5%. Under these conditions, the contents of amino acids and reducing sugar were the highest. There were 45, 48, 47 and 43 kinds of volatile compounds at the Maillard reaction temperature of 50, 60, 70 and 80 ℃, mainly including alcohol, aldehyde, acid, ester, ketone, furan and pyridine. When the Maillard reaction temperature was 60 ℃, the total amount of aroma compounds was the most, up to 497.85 μg/g, in which palmitic acid, myristic acid, benzyl alcohol, phenylacetaldehyde and tricyclic terpenes had high content. Dihydrokiwifruit lactone, damascone, oleamide and 2-pentylfuran were the key aroma components in tobacco, which contributed significantly to the aroma of tobacco. The waste tobacco buds were treated by Maillard reaction after enzymatic hydrolysis to prepare the spices, which provided a new method for the actual production of tobacco spices.

Key words: enzymatic hydrolysis, Maillard reaction, tobacco bud, process optimization