Studies On Modifications Of Konjac Glucomannan Polysaccharide And Quanlity Control

This paper is mainly focused on developing functional additive for beverage by modification of konjac glucomannan polysaccharide (KGM).In this paper, degradation of KGM by ultrasonic,acetylating modification,the functionality and application of KGM and KGMA in the dairy products were studied. Based on reasearching the modification process,critical quality control points(CQCP) were confirmed by HACCP system.In the process of degradation of KGM, influence of reaction conditions on the degree of degradation were studied.During the experiment, single factors` range was confirmed by single factor experiment: ultrasonic power was 250 to350W, degradable time was 7.5 to12.5 min, concentration of KGM was 3 to 5g·L-1.While reaction conditions were optimized by Response Surface Regression Experiment and the best degradable conditions were: ultrasonic power was 300W,degradable time was 10min 35s,concentration of KGM was 4g·L-1. In this section,the molecular weight (Mw)of KGM was 49,000 to 170,000 which is similar to aloe polysacchride.In the preparation of KGMA section, degree of acetyl was measured by hydroxylamine colorimetry. With the indicators of DS andη, the reaction conditions were optimized by orthogonal experiment: reaction time was 40min, reaction temperature was 60℃,mass ratio was 11∶1,sodium acetate was 0.6gram per KGM and the degree of acetyl was 0.68 which is also similar to aloe polysacchride.KGMA infrared spectra shows: during acetylation reaction process, primary structure of KGMA was not changed; but the quantity of acetyl was increased that shows acetylation reaction occurred.The KGMA solution belongs to pseudoplastic fluid and it was stable when the pH was 4.5 to 8.5, and the influence of Mw and DS on the pH stability of KGM were studied respectly,the results were as follows: Mw to the pH stability: 300,000>150,000>50,000,DS to pH stability: 0.5>0.3>0.68 and molecular weight was more important for the stability than DS. DS increase was good for the stability, but molecular weight was not .With the Mw above 10,000 and DS above 0.6, KGMA was suitable for diary products.the X-ray diffraction showed the crystal degree of the solid in diary was decreased .HACCP system was applied in the processing of modification Quality Control and potential Hazard Analysis was carried out. There were four Critical Qulity Control Points: (CQCP1, check and accept of KGM; CQCP2, check and accpte of chemicals and pakage materials; CQCP3,degradation;CQCP4, acetylating;) and Critical Limits, Monitoring Procedures, Corrective Actions of each CQCP,Quanlity Control Plan Table were also established so that we can improve the plan and research of the new product.