Addition of a mushroom by-product in oil-in-water emulsions for the microencapsulation of sunflower oil by spray drying

Abstract

The by-product generated after ergosterol extraction from mushrooms (A. bisporus) is rich in polysaccharides (β-glucans) and proteins. The usefulness of this mushroom’s by-product (MC) in oil microencapsulation by spray drying was evaluated partially replacing maltodextrin (13.5% w/w dry matter) and totally substituting Tween®20 with MC. Ergosterol was investigated as antioxidant. Non-Newtonian stable emulsions with mono-modal droplet size distributions were obtained with MC. Oil encapsulation efficiency was high (≥89%) and oil within microcapsules containing MC exhibited higher (p < 0.05) oxidative stability during spray drying. Powders containing MC exhibited larger particles (d5027% larger), 12% lower solubility in water and perceptible color changes. During storage (35 °C 50% RH), conjugated dienes increased more slowly in microcapsules containing MC. Reductions up to 28% in linoleic acid were observed after 150 days. Ergosterol was 95% degraded after 150 days in powders with MC and totally degraded after 2 days in powders without MC.