Study On The Production Technology Of Liquid Fructose From Apple Juice

Over the past 10 years, China, which produces up to 65% of the world's apples, has become the top supplier of concentrated apple juice in the world. Concentrated apple juice has become one of the important export agricultural products in China.The acidity of concentrated apple juice produced in China is about 1.8%, whereas the acidity of concentrated apple juice produced in other countries is above 1.8%.The price of China's concentrated apple juice is lower than high acid concentrated apple juice produced in other countries.So how to increase the acidity of China's concentrated apple juice is the critical point of solving this export problem.The research shows that the fructose and glucose contents were about 52% and the sucrose content was about 16% in apple juice respectively. Apple juice is rich in fructose and is the high quality raw material for producing high quality fructose. The kinetics of separation of fruit acid in apple juice was studied.The static adsorption capacity, dynamic adsorption capacity and adsorption equilibrium time were achieved through this study.The optimum dynamic adsorption condition was also achieved.The distribution of nutrient matters in preparing process of concentrated apple juice were studied,using Granny Smith,Fuji Apple and Qin Guan Apple.The technology of preparing high acid concentrated apple juice through fruit acid separation and adding fruit acid into middling acid apple juice were also achieved.The optimum conditions of sucrase enzymolysis and decolourization condition of apple juice were achieved. The achievements of this study can resolve the problems which restrict the export of China's concentrated apple juice.Liquid fructose can be produced using apple juice. optimumThe main results of this study:1. It indicated that: Resin D380 had the highest absorption efficiency, and the static adsorbance was 30.73 milligram per microlitre wet resin. The absorption balance time was 270min. Dynamic adsorbance reached 60.24 mg/mL. The optimum concentration of juice for absorption was 11Brix.2. The results showed that:①the nutrient content of Granny Smith strain was superior to Fuji and Qinguan strains;②the parameters of best fruit acid separation efficiency for the D380 resin were: temperature 25℃, juice density 30%(in terms of sugar content), flow velocity 3ml/min;③The best elution condition were: 50% ethanol as the eluent, temperature 25℃, flowing velocity 6ml/min, 3 times elution, and the volume scale of eluent versus resin was 2:1.This research proved that it was possible to make the medium acidic apple juice concentrate to be high acidic by adding the separated fruit acid.3. the optimal condition of sucrase digestion were: pH4.5, apple juice concentration 12Brix, sucrase concentration Tmg.kg^-1 and temperature 55℃.4. Decolourization condition of resin XDA-5 were: pH3.5, concentration of apple juice 20Brix, temperature 50℃and fluid velocity 150mL.h^-1.