Development and Characterization of Blended Açaí-Sunflower Oil Emulsions Stabilized with Modified Starch and Maltodextrin for Incorporation into Yogurt

Açaí oil (AO) is extracted from the pulp of the açaí fruit (Euterpe oleracea Mart.), a species native to the Brazilian Amazon region. The oil is recognized for its bioactive compounds and antioxidant properties, making it promising for functional foods. In this study, a commercial lipid blend containing 40% açaí oil and 60% sunflower oil (SO) was emulsified using modified dextrin (Capsul®), maltodextrin, and xanthan gum. The selected formulation, containing 8% of the oil blend, exhibited satisfactory physical stability over 30 days of refrigerated storage, with a mean droplet diameter of 7.3 µm on day 1, remaining within 7–8 µm throughout storage. The peroxide value increased from 2.09 to 3.95 mEq/L emulsion, whereas TBARS decreased from 1.86 to 1.51 mmol MDA/L emulsion. DPPH and ABTS apparent antioxidant activities remained relatively stable over the storage time. Yogurts containing 8%, 10%, and 12% of the oil-blend emulsion and 5% inulin were evaluated for physicochemical, antioxidant, rheological, microbiological, and sensory acceptance. Emulsion incorporation modified yogurt structure and rheological behavior while maintaining microbiological safety. Sensory acceptance scores ranged from approximately 6.0 to 7.4 on the nine-point hedonic scale. Overall, the emulsions effectively incorporated the blended oil into yogurt, providing desirable technological, antioxidant, and sensory properties.