Alkali Extraction of Dietary Fiber from Trigonella-foenum graecum L. Seeds (Dietary Fiber of Fenugreek Seeds)

In this study, alkali dietary fiber extraction method was evaluated to obtain soluble and insoluble dietary fiber from Trigonella-foenum graecum L. (fenugreek) seeds. The process conditions of alkali extraction method ensuring the highest total dietary fiber yield were investigated by response surface methodology. Furthermore, some physicochemical and functional properties of extracted soluble and insoluble dietary fiber from fenugreek seeds such as water retention capacity, oil adsorption capacity, swelling capacity, glucose adsorption index and α-amylase inhibition capacity were determined. Total dietary fiber yield was 78% at 52.50 g/L of sample: NaOH ratio and 1.01 M NaOH concentration as the optimum process conditions. Furthermore, insoluble dietary fiber gave better results than soluble dietary fiber when physicochemical and functional properties were compared.