Optimization of ultrasonic-assisted extraction of soluble dietary fiber (β-glucan) from different barley varieties and study of its characterization and functional attributes

Abstract

Green technology, encompassing sustainable practices in food production, extends to dietary fiber extraction. This study aimed to enhance dietary fiber extraction from the selected barley varieties (Jou-17, Sultan-17, and Pearl-21) using the ultrasonic-assisted extraction (UAE) technique. This process involved washing, drying, de-fatting (using ethanol as green solvent), and protein removal steps. The response surface methodology (RSM) technique was used to optimize the yield of soluble dietary fiber (SDF; β-glucan) with time, temperature, and power. Optimal conditions yielded the highest SDF (5.21%) in all selected varieties after 17.5 min at 41.70°C with 130.5 W. FTIR pattern confirmed the functional group in the tested sample. TGA and DSC spectra determined the thermal of SDF (β-glucan). Monosaccharide composition confirmed that SDF (β-glucan) is glucose in nature. Proximate analysis indicated that Jou-17 had the highest moisture (13.4%) and crude fiber (10.10%) content. Sultan-17, on the other hand, had the maximum levels of ash (2.75%), crude fat (1.22%), and protein (8.84%). The NFE, water-holding capacity, oil-holding capacity, and foaming capacity of extracted SDF (β-glucan) in the “Pearl-21” barley variety were determined to be 78.37%, 14.07 g/g, 6.99 g/g, and 126.17%, whereas highest foaming-stability (96.26%) was observed in Jou-17 variety. PCA also confirmed the association in studied variables. In a nutshell, optimizing the extraction of SDF (β-glucan) from the selected barley varieties using green technology and its favorable properties opens up promising paths for future endeavors and contributes to the advancement of sustainable and health-conscious practices in the food industry.

Keywords Green Extraction, Polysaccharides, RSM, Sonication