Increased consumer interest in omega-3 fatty acids (FA) has led to novel foods with added omega-3 FA. Additional information regarding omega-3 FA fate within foods is needed for improving quality and stability. This research modeled DHA, an omega-3 FA, fate and explored means of preventing degradation and oxidation of FA in algal oil and mozzarella cheese.
In algal oil, TBHQ (synthetic antioxidant) at 0.0175g/g algal oil prevented DHA degradation for at least 6 weeks, and mixed tocopherols (natural antioxidant) at 400ppm prevented DHA degradation and oxidation for about 4 weeks. DHA degradation in algal oil was modeled by an autocatalytic equation.
The fate of DHA from algal oil in mozzarella cheese was also modeled by an autocatalytic equation. In an effort to prevent DHA degradation and oxidation, mixed tocopherols were added. The optimum combination of those tested was found, using a response surface design, to be 3% algal oil with 110ppm mixed tocopherols for maximum DHA and minimum oxidation over 2 weeks. This algal oil/antioxidant combination in mozzarella cheese successfully prevented oxidation and DHA degradation over 3 weeks of storage. Approximately 0.1g DHA may be consumed from a 28g serving of this cheese. Approximately 0.5-18 servings of this cheese are equivalent to DHA consumed from a 3oz serving of fish, depending on fish type. Sensory evaluation tests found consumers could distinguish between mozzarella cheese with/without algal oil. Results from this study improve understanding of omega-3 FA behavior in mozzarella cheese and provide a means for preserving quality and nutrition.
