关键词: 大豆膳食纤维, 生物解离, 可溶性膳食纤维, 理化性质, 功能特性

Abstract: The residue from biological dissociation (BD) of soybeans can be considered as a rich source of dietary fibers due to its richness in dietary fibers. In order to investigate the effect of BD on the quality of soybean dietary fiber and hence to obtain high-quality soybean dietary fiber, the chemical composition, physicochemical and functional properties of the resulting soybean dietary fiber were determined and compared with those obtained from water extraction, chemical treatment, fermentation and water extraction following extrusion pretreatment. The results showed that the purity of dietary fiber prepared by BD was 82.58%, and approximately 60% of the total dietary fiber was soluble, suggesting that high-quality dietary fiber was obtained. The water-holding capacity, oil-holding capacity, expansibility and solubility of dietary fiber from BD were 6.87 g/g, 5.48 g/g, 8.22 mL/g and 5.07%, respectively, which were significantly higher than those of dietary fibers from other extraction methods. The results of functional properties showed that the functional properties of dietary fibers from different extraction methods were in the decreasing order of BD, extrusion, fermentation, chemical extraction, and water extraction. In addition, the adsorption capacity of BD dietary fiber toward Pb2+, As3+, and Cu2+ were 351.2, 304.1 and 214.1 μmol/g at pH 7.0, respectively. The glucose adsorption capacity, α-amylase-inhibitory activity and bile acid retardation index were 6.56–35.78 mmol/g, 18.42%, and 33.12%–35.52%, respectively, which were significantly higher than dietary fibers from other extraction methods. Therefore, the residue from biological dissociation of soybeans has good physicochemical and functional properties, indicating that it has great potential for application in the food industry as a new source of dietary fiber.

Key words: soybean dietary fiber, biological dissociation, soluble dietary fiber, physicochemical properties, functional properties