Characterization of pickering emulsions stabilized by nano dietary fiber from Lentinula edodes stipes

Abstract

Waste Lentinula edodes (L. edodes) stipes from L. edodes were utilized as raw materials to obtain dietary fibers through a purification process. Following a 24-h cellulase hydrolysis, dietary fibers were subjected to cell disruption with varying durations. Differences in the monosaccharides composition, microscopic structure, size, zeta potential, contact angle, crystallinity, and functional groups of the nano dietary fiber produced through combined cellulase hydrolysis and cell disruption were analyzed in comparison to those obtained through cell disruption alone. Results indicated that the spacing between the nano dietary fibers was increased, and their particle size was reduced by cellulase hydrolysis followed by cell disruption. The wettability of the nano dietary fiber was enhanced by enzymatic treatment, whereas it was reduced by cell disruption. Either treatment did not compromise the crystalline regions of the nano dietary fiber; rather, the crystallinity was increased. Additionally, to emulsify corn germ oil, the prepared nano dietary fiber was employed, resulting in Pickering emulsion formation. A 45-min optimal cell disruption duration produced emulsions with a more uniform dispersion and the smallest particle size. Improved oil droplet encapsulation was exhibited by the emulsions prepared from dietary fiber that underwent cellulase hydrolysis followed by cell disruption, thereby leading to a decrease in free fatty acid release. The stability mechanism of the EEU_24–30 emulsion was attributed not only to the adsorption of the nano dietary fiber onto the oil droplets but also to the formation of a three-dimensional network structure that further enhanced the emulsion stability.