Studies On Processing Technology Of Small Or Medium Sized Apples

This article took 4 small or medium sized apples in Heilongjiang Province as test materials(K₉, Jinhong, Huangtaiping, Lingdang). Tested their Chemical Index separately, according to quality index of processing apples that required: high juice yields, approprite brix and acid ratio, light browing etc., selected K₉ as test matierials in this experiment.Took K₉ as test materials, studied the key control point on processing techniques of small or medium sized apples: pretreatment techniques, enzymolysis techniques, clarification techniques and concentration techniques.In pretreatment techniques, compared 4 heating methods that influence the quality index: juice yields, browning degree, losses values of Vc, dissolubility solids and total acid. After comprehensive consideration, selected water blanching lmin, break up 30s as pretreatment techniques.According to single factor and orthogonal test with pectin enzyme, established the optimum enzymolysis parameter. In single factor enzymolysis, when enzymolysis temperature was 50℃, enzymolysis time was 4h,enzymy addition level was 900u/100g, had the best quality index. Based single factor experiment, took breed, enzymolysis temperature, enzymolysis time, enzymy addition level do 4 factor 4 level orthogonal test, results showed when breed selected K₉, enzymolysis temperature was 50℃, enzymolysis time was 4h, enzymy addition level was 800u/100g, had the best index. Under this technology, juice yields improved 41%, total sugar improved 27%, dissolubility solids improved 9%, total acid improved 39%, protein and total phenol were not reduced, color value was reduced 82%. Breed was the main factor that influnce the quality index, after that was enzymolysis temperature.3 Clarification test was done which used apple juice that enzymolysised by optimun techniques: centrifugal purification, chitoson clarification and ultrafiltration membrance clarification. Results showed, when rotating speed was 4000r/min, rotated after 25min, centrifugal purification had the best light transmittance 94.07%.With chitosan additives, experimentized addition level, clarification time, clarification temperature with single and orthogonal test. In single factor test, when chitosan added on was 0.3g/L, clarification temperature was 60℃, clarification time was 220min, had the best light transmittance. Orthogonal test showed, when chitosan addition level was 0.3g/L, clarification temperature was 50℃, clarification time was 180min, had the best light transmittance, and was over 95%. In ultrafiltration experiment, used 3 different mol.wt cut membrance( Ultra-50, Ultra-30, Ultra-10 that cut melecular weight was 50000,30000,10000) to made consolidation line, calculated...