Research Of Clarification Vinegar With Immobilized Enzyme

Vinegar is a traditional acidic condiment, with various health functions and nutritional value. However, because of its technical characteristics, brewing and storage process will form turbidity and precipitation. The turbidity and precipitation in vinegar not only seriously affects domestic acceptance of vinegar, but also the vinegar export. Therefore, vinegar turbidity and precipitation phenomenon is a serious problem. At present, there is no clarification method can clarify while maintain the nutritional value, especially has a low-cost. In order to reduce the precipitation in vinegar, improve product quality and acceptance, and maintain the nutritional value, we used glucoamylase, pectinase and vinegar acid protease to biodegrade pellet major macromolecules in the precipitation, and used the immobilized enzyme to clarify vinegar. Glucoamylase, pectinase and vinegar acid protease were used to biodegrade pellet major macromolecules in the precipitation, and the immobilized enzyme was utilized to clarify vinegar. The Synergy between three gels of sodium alginate, agar and guar gum was utilized to prepare composite gel, which was then used to immobilize glucoamylase, pectinase and protease acidic. The effect of enzyme's content, curing time and curing liquid CaCl2 concentration on immobilization was investigated, and optimized immobilization condition was obtained by using response surface methodology. The effect of immobilized enzyme on vinegar clarification under optimal condition was investigated. The main results are as follows:(1) The best glucoamylase immobilized carrier was agar-guar gum composite gel, and the best composite immobilized gel concentration was 2.0g/100mL, with the best carrier ratio was agar:Guar gum as 2:1. The optimal conditions of glucoamylase immobilization was that the amount of enzyme was 30mg/ g carrier, while the concentration of enzyme and curing solution CaCl2 was 6.0% and 3.0%, respectively, for a best soliding time of 1h.When using the immobilized glucoamylase, the immobilized enzyme dosage was 8g/100mL, for a processing time of 24h, after the treatment, vinegar, light transmission rate up to 99.4%, compared with the original vinegar improves the transmittance of 3.9%.(2) The best pectinase immobilized carrier was sodium alginate-agar gel composite. The optimal clarification condition were that the composite immobilized gel concentration was 3.0%, with the best ratio of sodium alginate of carriers:Agar as 2:1. The optimal conditions of pectinase immobilization was that the amount of enzyme was 31 mg/g carrier, while enzyme and curing liquid CaCl2 concentration was 2.1% and 2.1%, respectively, for a best soliding time of 6.8h. When using the immobilized pectinase, the immobilized enzyme dosage was 4g/100mL, for a processing time of 12h, after the treatment, vinegar, light transmission rate up to 98.2%, compared with the original vinegar improves the transmittance of 2.7%.(3) The best acid protease immobilization carrier material was alginate-guar gum composite gel. And the optimal condition was that the immobilization of composite gel concentration was 2.5g/100mL, with the best ratio of sodium alginate:guar gum to be 2:1. The optimal conditions of acid protease immobilization was that the amount of enzyme was 1.7mg/g carrier, while enzyme and curing liquid CaCl2 concentration was 2.1%, and 2.1%, respectively, for a best soliding time of 6.8h, the immobilized enzyme prepared in this condition up to the maximum of its activity. When using the immobilized vinegar acid protease the immobilized enzyme dosage was 1.5g/100mL, for a processing time of 8h, after the treatment, vinegar, light transmission rate up to 99.1%, compared with the original vinegar improves the transmittance of 3.6%.(4) When used both of immobilized glucoamylase and immobilized pectinase for vinegar together for clarification, the maximum light transmission rate was 99.7%, while that for both of immobilized pectinase and immobilized acid protease was 99.5%, which were superior to clarify the effect of an individual immobilized enzyme treatment.(5) Three kinds of enzymes and a combination of two of them were used for vinegar clarification treatment, and the results showed good clarification effect. Based on the physical and chemical indicators of vinegar before and after treatment, the immobilized enzyme treatment approach had no adverse effects of vinegar quality. And by the enzymatic decomposition of macromolecules, reducing sugar and amino nitrogen content of vinegar increases, so the immobilized enzyme treatment is an ideal vinegar clarification method.