Abstract: Kudzu plants are widely distributed in China. The total content of dietary fiber (DF) in the root dreg reaches over 70%. The root dreg is a kind of natural sources of dietary fiber. The optimal technology parameters were been studied for four kinds of kudzu root dietary fiber with enzymatic hydrolysis, by using single factor and orthogonal design experments. Results showed that the best conditions for preparation evalusted by DF swelling ability were:(1)mixed enzyme(a-amylase: glucoamylose, 1:2) amount of 0.2%, 70℃,80 min for treatment; and (2) proteinase amount of 0.3%, 50℃,60 min for incubation(Table 1,Fig.6,Fig.7).After incubation of mixed enzymes and proteinase, the acid detergent fiber contents of four kinds of dietary fibers in the wild and cultivated kudzu in Zhangjiajie and Yueyang, Were increased to 78.69%,78.41%,76.34% and 73.11%, respectively(Table 2). Therefore this technology of enzymatic preparation may lay the foundation of processing for kudzu root dietary fiber.

Key words: Pueraia lobata Ohwi, Dreg of kudzu vine root, Dietary fiber, Protein enzyme, Mixed enzyme, Purification