Study On Preparation And Physical-chemical Properties Of Pectin From Jiashi Melon Rind

In this study, Xinjiang Jiashi melon- processing waste resources rind as a raw materials, to explore a practical, efficient method of pectin extraction purification, concentration, precipitation, drying and determination of its important features, in order to develop high quality and new products of Jiashi melon rind pectin, to turn waste into treasure, to provide the basis for the development of comprehensive utilization of Jiashi melon and pectin resources. The main topic was study the Preparation and physicochemical properties of pectin from the Jiashi melon rind, the results are as follows:(1) To rind of the Jiashi melons as raw materials,the optimization extraction condition of pectin through acid treatment conditions was investigated by orthogonal test and optimization extraction condition of pectin by acid extraction combined with microwaved and the enzyme combined with microwaved was investigated by the response surface.The results showed that,of all 3 kinds of methods enzyme extraction combined with microwave. had the highest extraction rate, the optimal process parameters were determined:enzyme dosage was 3U/mL, time was 120 s, the temperature was 60℃, the extraction rate of pectin reached 6.81%. Microwave extraction of pectin enzyme with yield, high purity, light color, and acid extraction required more than four small time can be shortened to two minutes, significantly increased Jiashi melon pectin extraction rate.(2) The condition of resin purification, membrane concentration and precipitation conditions of pectin was researched. The results showed that, compared with of all five kinds of the AB-8 macroporous resin adsorption was shown excellent adsorption capacity and higher than that of the other four, the static was 87.86mg/g, the elution rate was 90.88%. The optimum conditions was as followed:p H=5 ~ 6, 60% ethanol concentration, column liquid concentration 4BV,flow rate was 2BV/h; of all threekinds of membbrance,the flux and yield of the ultrafiltration efficiency of 10 kDa.the was higher than that of the other two, membrane concentration optimum parameters: pressure, 0.3MPa the temperature of 40℃, the as the index,condition of the highest rate of pectin by ethanol precipitation was as followed: when pH=4, the temperature was 60℃, ethanol concentration was 75%, time was 60 min.(3) The optimization condition of vacuum drying and spray drying process was investigated by orthogonal test. The pectin yield and moisture content was used as the index. The results showed that, the optimal conditions for pectin vacuum drying: vacuum 0.06 MPa, temperature 40, time 6h. The pectin yield reached 68.44%, the moisture content was 2.18%. The best drying parameters for spray drying of pectin: inlet temperature of 130℃, injection speed of 400mL/L, air temperature is 75 degrees centigrade, pectin yield reached 80.12%, the moisture content was 5.63%.(4) The national standard method was used of for the physicochemical properties of pectin in Jiashi melon rind The results showed that,the degeree of esterification of Jiashi melon pectin, galacturonic acid, dry weight loss, total ash, pH values was 53.55%, 75.12%, 3.45,5,57 %,4.33%. pectin color, properties identification test, determination of rheological properties, solubility, thermal stability and acid resistance was good, the physicochemical properties of pectin was consistented with the standard.