Abstract: Tobacco extracts are important tobacco flavors, but macromolecular impurities such as pectin can have adverse effects on the sensory quality. To reduce pectin content and to improve quality and aroma of tobacco extracts, a composite carrier of gel beads with sodium alginate-gelatin (SA-GE) were built to immobilize pectinase. By conducting single-factor experiments and the response surface optimization, the preparation process of pectinase immobilization was optimized and its application effects in tobacco extracts were evaluated. The results showed that: 1) When the total content of SA and GE was 4% and m(SA)∶m(GE)=1.0∶1.0, the immobilization capacity of pectinase was high, and the enzyme activity recovery rate of pectinase was the highest. Under the conditions of an initial pectinase content of 3%, an immobilization temperature of 33 ℃, an immobilization pH value of 3.6, and an immobilization time of 3.5 h, the enzyme activity recovery rate reached 46.99%. 2) Compared with free pectinase, the immobilized pectinase maintained a high relative enzyme activity when both the contents of ethanol and propylene glycol were 50%. When the pH value was 1-7, the stability of immobilized pectinase was relatively high. When the temperature was 80 ℃, the relative enzyme activity of immobilized pectinase was 63.47%. After 5 repeated uses, the relative enzyme activity still exceeded 40%. 3) After adding Yuyan extract treated with immobilized pectinase to cigarettes, the cigarette samples exhibited enhanced sensory performance with increased aroma richness, reduced off-notes, and significantly diminished irritation. This study demonstrates the feasibility of improving the quality of tobacco extracts through SA-GE composite gel immobilization technology, providing a new pathway for enhancing the quality and efficiency of tobacco extracts.