Delivery of bioactive fatty acids in dairy matrices

Abstract

Addition of beneficial unsaturated fatty acids into dairy food provides relevant healthproperties. However, they are unstable and susceptible to environmental conditions suchas oxygen, light, temperature, pH and ionic charge, and can decrease both food functionalityand quality. Our research focuses on two approaches to achieve stability of bioactivefatty acids: encapsulation and homogenization. For the first approach we have studiedliposome delivery, formulating CLA-liposomes as ingredients for dairy applications. Wecharacterized the vesicles morphologically (TEM microscopy), in size (by DLS), for encapsulationefficiency (GC) and resistance to freeze-drying. Besides, we assessed the performanceof the liposomes as an ingredient in yoghurt. They showed resistance to thermaltreatment, oxidation stability and high CLA recoveries. No detrimental effects were found.For the second approach, we used a homogenization step to incorporate CLA in yoghurtmilk. We studied the effect of CLA at two levels on fermentation, particle size distribution,CLA content, fatty acids profiles, oxidative stability and physicochemical properties. Wesuccessfully increased CLA in all formulations.