Drying aids are important for improving the quality properties of food bioactive compounds in coacervated microcapsules. The purpose of this work was to systematically explore the effects of low molecular weight carbohydrates as drying aids on the preparation and properties of fish oil powders. Three carbohydrates (monosaccharide glucose, disaccharide sucrose and trehalose) were used as drying aids to prepare freeze-dried fish oil@gelatin-pectin@carbohydrate powders, and their effects on powder properties were studied. The carbohydrate coating enhanced oil oxidative stability and delayed the release of free fatty acid (FFA) during in vitro simulated digestion. Compared with the monosaccharide, the disaccharides resulted in lower FFA released percentages (52.2–58.5% vs. 64.4% at 2 h). However, the disaccharides led to higher color differences (1.44–2.51 vs. 1.06), larger particle sizes (D50 = 147–170 vs. 106 μm), increased bulk densities (0.09–0.11 vs. 0.08 g/cm3), higher tapped densities (0.15–0.18 vs. 0.14 g/cm3), improved loading yields (91.5–98.1% vs. 84.3%), higher loading capacities (26.3–28.6% vs. 24.2%), greater encapsulation efficiencies (98.3–98.7% vs. 97.9%), and elevated peroxide values (540–602 vs. 517 mmol/kg oil) than the monosaccharide. The results indicate that low molecular weight carbohydrates are promising drying aids for fish oil encapsulation and contribute to understanding the relationship between carbohydrate drying aids and the properties of oil powders.
Zhang et al. (Wed,) studied this question.