Influence of high hydrostatic pressure treatment on the soluble dietary fiber content and physicochemical characteristics of edamame

We used non-thermal high hydrostatic pressure (HHP) technology to process edamame to increase the soluble dietary fiber content of the product. We also comprehensively explored the impact of HHP on the functional properties and fiber structure of edamame. Edamame was treated at a high pressure of 600 MPa for 5-, 10-, and 15-min. Edamame treated with HHP exhibited elevated water-holding, oil-holding, and water-swelling capacities, which were attributed to alterations in the fiber structure. Scanning electron microscopy, used to assess the porous characteristics of the surface, revealed gaps that could retain liquid. This structural modification facilitated enhanced in vitro performance in cholesterol adsorption and bile acid-binding force tests. X-ray diffraction analysis revealed that the broken fibers strengthened the (101) crystal plane of fiber crystal I; the reduction in crystallinity caused the fibers to form a loose structure under thermal stability, which increased the water retention and swelling properties. HHP destroyed part of the fiber structure, contributing to the altered functional properties. The findings indicate that HHP treatment adds significant value to edamame, making it a promising raw material for developing functional foods and healthcare products.