Study On The Preparation Of Resistant Maltodextrin By Microwave And Its Properties And Application

Resistant maltodextrin is of certain physiological functions as a new type of soluble dietary fiber. In this thesis, we studied the producing of the resistant maltodextrin by microwave from starch.Firstly,the resistant maltodextrin was prepared with catalyzer of nitric acid and hydrochloric acid respectively,and hydrochloric acid was chosen to be the catalyzer of resistant maltodextrin preparation by comparation. The effects of normal corn starch and waxy corn starch on resistant maltodextrin were studied. On the basis of single-factor experiments, the effects of different acid weight percent, microwave power and treating time by microwave on the resistant maltodextrin yield and whiteness from resistant maltodextrin were investigated with a three-factor Box-Behnken center-united design. The parameters were optimized with Response Surface Methodology. The result of normal corn starch indicated that the conditions of 6.43% acid, 630 W and 10.12min of microwave were optimum, and the yield of resistant maltodextrin could be 43.30% and 76.9% on whiteness. The result of waxy corn starch indicated that the conditions of 6.16% acid, 645w and 9.40min of microwave were optimum, and the yield of resistant maltodextrin could be 47.84% and 79.88% on whiteness. Waxy corn starch was decided to be the material of resistant maltodextrin based on test.Secondly, the characteristics of resistant maltodextrin were analyzed. The results showed that the intrinsic viscosity, stability, solubility, freezing and thawing, transparency and thermal stability were all good and suitable for beverage. The results of HPLC revealed that the structure of resistant maltodextrin was complex.Finally, syrup containing resistant maltodextrin was prepared by enzyme. Based on the single factor experiments, the optimum conditions of enzyme adding were:0.2%α-amylase, 0.4% glucoamylase, 3% active carbon and 3mL/min cleansing solution velocity. The optimum conditions of the technology to prepare sports drink were got by sensory score in the orthogonal experiments: 0.15% citric acid, 0.5% fructose and 15% resistant maltodextrin syrup.