柿饼干制过程中理化性质的变化规律研究

为探索柿饼干制过程中柿饼的生理生化变化规律,以求为柿饼的干制方法和工厂化生产提供理论依据,采用对比试验,研究柿饼人工控制干制和自然干制过程中柿子中的水分、单宁、原果胶、水溶性果胶、乙醇、乙醛、乙醇脱氢酶活性和果胶酶活性的变化规律,测定自然干制过程二氧化硫含量的变化,比较人工干制与自然干制柿饼的卫生状况。柿饼的人工干制与自然干制过程中的水分、单宁、原果胶、水溶性果胶、乙醇、乙醛、乙醇脱氢酶活性和果胶酶活性的变化趋势一致,而人工干制的时间是自然干制时间的1/7,人工干制柿饼不受天气影响,无二氧化硫残留,细菌总数只有23 CFU/g,而自然干制需要进行6次二氧化硫熏蒸防霉,最终产品二氧化硫残留量高达150 mg/kg,细菌总数达3500 CFU/g,是人工干制细菌总数的152倍。证明柿饼的人工干制完全可以替代自然干制过程。

Patterns of the Physiological and Biochemical Changes during the Persimmon Drying Process

The aim of this study was to explore the pattern of the physiological and biochemical changes in persimmons during the drying process and provide a theoretical basis for the best method to dry and produce persimmons in a factory. The patterns of changes in moisture, tannins, original pectin, soluble pectin, ethanol, and aldehyde content, and the alcohol dehydrogenase and the pectinase activities of persimmon during artificial and natural drying processes were investigated and compared. The changes in the sulfur dioxide content during the natural drying process was determined, and the total number of bacteria in dried persimmon samples prepared by artificial and natural drying processes were compared. The results showed that the moisture, tannins, original pectin, soluble pectin, ethanol, and aldehyde content, and the alcohol dehydrogenase and the pectinase activities of the dried persimmon samples prepared by artificial and natural drying processes were consistent, but the artificial drying process required about one-seventh of the time required for natural drying. Dried persimmons prepared from artificial drying were not affected by the climate and did not contain sulfur dioxide residue, and the total number of bacteria was only 23 CFU/g. Nevertheless, for natural drying process, the persimmon needed to be fumigated six times with SO2 to prevent mildew, the dried persimmon prepared from natural drying contained 150 mg/kg sulfur dioxide residue, and the total number of bacteria was 3500 CFU/g, which was 152 times of that in the dried persimmon prepared by artificial drying. The above findings showed that the artificial drying process could completely replace natural drying for producing dried persimmons.