Fiber-rich ingredients obtained from agroindustrial residues through combined hydrothermal-chemical processes

Abstract

The objectives of this study were to evaluate the composition and techno-functional properties of fiber-rich ingredients that were obtained from three agroindustrial residues (oat, soybean, and coffee hulls) through a one-step hydrothermal-chemical combined process. The residues were subjected to an alkaline hydrogen peroxide treatment (2%, pH 11.5) combined with a hydrothermal treatment in an autoclave (121 °C/30 min/1.5 atm). Ash, protein, and lipid contents decreased for all residues, and total (up to 86 g/100 g) and insoluble dietary (up to 83 g/100 g) fiber contents increased for all processed residues. All treated samples exhibited an increase in hydration capacity, with values ranging from 5.2 to 6.6 g/g of water absorption capacity and 5.6 to 5.7 g/g of swelling capacity. The one-step process was efficient in improving the nutritional and techno-functional quality of the residues of oat, soybean, and coffee, and it can be considered a promising alternative for future obtaining of new fiber-rich ingredients.

Keywords

• Oat, soybean, and coffee hulls
• Hydrothermal treatment
• Alkaline hydrogen peroxide