Summary: | 碩士 === 國立屏東科技大學 === 食品科學系所 === 96 === Pectinolytic enzymes are usually used in winemaking for clarification and yield increasing of juices and wine making , extraction of oil and color from vegetables and fruits , so commercial pectinolytic enzyme is important in making wine. The PE can catalysis the de-esterification reaction, the methyl ester group on the C6 carboxyl of D- galacturonic acid in the pectin could be hydrolyzed by PE to produce the free carboxyl group and the methanol. Methanol usually causes headache, vertigo, vomiting, blurred vision, blindness and even death, so, the separation of pectinesterase from pectinase is needed in wine making. The commercial pectinolytic enzymes is affinity to the 83 DE and 50 DE cross linking alcohol insoluble substances, the PL of pectinase could be separated with the PE, the remaining PL containing 445 unit/mg of PG and 8.3 unit/mg of PL, the purified fold of PL was 6.7 and the recovery was 84.3%, the separated PE containing 100 unit/mg PE, PG 6.5 unit/mg and PL 82.4 unit/mg, the purified fold was 4.8, and the recovery was 68%, the removing PE from commercial pectinolytic enzymes could be used in sweet orange wine making for methanol reducing. The result showed the transparency increases in the fermentative process along with the time increase with pectin enzyme function on pectin, all adding pectinolytic enzyme groups that were slightly different form the control, the result all showed adding commercial pectinolytic enzyme and adding PE alone, the methanol content was 60 ppm and 85 ppm respectively, the methanol were higher than the other test, there were no any obvious difference on the physical property of the tests except on methanol content.
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