Physicochemical Stability and Sensory Evaluation of Novel Fish Oil Fortified Plant Milk Beverages

Omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are imperative for general biological functions and may be involved in the prevention and treatment of various diseases. Despite the benefits, US consumption of fish, and consequently EPA and DHA, is below recommended levels. Developing an alternative food product which contains EPA and DHA is a strategy to increase consumption. In this study, 1% fish oil (FO) was emulsified and incorporated into plant-based milk beverages and compared to 1% high-oleic sunflower oil (HOS) controls. The HOS and FO beverages were analyzed for their physicochemical stability, comparing three different beverage bases: soy, oat, and almond, and water. It was found that oat and almond milk were the most physically stable to emulsion separation and sedimentation, and there were no differences between control sunflower oil and fish oil. Soy and oat milk with fish oil were most resistant to oxidation compared to other fish oil-fortified beverages. Following the physicochemical study, the consumer rejection threshold of FO in the three plant milk beverages was investigated. Generally, 0.2% of fish oil could be added to oat and soy milk without causing consumer rejection, containing approximately 360 mg of combined EPA and DHA per 240 mL serving. Almond milk was found to be a poor vehicle for fish oil, as any concentration led to rejection. This study provides valuable preliminary data to support fortifying oat or soy milk with EPA and DHA to increase intake; however, further optimization of beverage functional characteristics and flavor is needed.