The effects of different extraction methods on physicochemical, functional and physiological properties of soluble and insoluble dietary fiber from Rubus chingiiHu. fruits

Abstract

• IDF and SDF extracted from Rubus chingii Hu. fruits by four methods are analyzed. • W-SDF and AC-SDF represented distinctive features in physicochemical properties. • W-SDF and AC-SDF displayed the excellent oil holding capacity in vitro. • W-SDF and AC-SDF promoted oil excretion and decreased oil absorption in vivo. In this study, we compared the chemical, physical, and functional properties of insoluble dietary fiber (IDF) and soluble dietary fiber (SDF) that were extracted from Rubus chingii Hu. fruits using four methods. The results showed a wide variation in structural and functional properties among IDFs and SDFs extracted by different methods. Compared with the other DFs, water extraction SDF (W-SDF) and acid extraction SDF (AC-SDF) exhibited a more complete structure, higher thermal stability, and larger apparent viscosity, which in turn enhanced their functional properties. Notably, the oil holding capacity of W-SDF and AC-SDF reached very high levels at 19.89 ± 1.47 g/g and 12.62 ± 1.31 g/g, respectively. In vivo experiments in mice showed that W-SDF and AC-SDF effectively inhibited soybean oil absorption, promoted its release from the body and decreased serum triglyceride levels. In summary, W-SDF and AC-SDF from R. chingii fruits can effectively reduce the absorption of fats.