Spray-drying microencapsulation of fixed oils: An innovative and sustainable technology to enhance oxidative stability, functionality and application in food systems

Fixed oils are economically valuable due to their diverse applications in foods and other industrial processes. However, their potential is limited by instability under harsh conditions, such as oxidative stress and high temperatures, largely due to their high polyunsaturated fatty acid (PUFA) content, restricting their direct use in food products. Innovation on the preservation of PUFA for improved stability and application in the food industry has focussed on a number of technologies that includes microencapsulation. Microencapsulation is an effective, sustainable technique that protects PUFA and bioactive phytochemicals, such as tocopherols, polyphenols, and carotenoids, from degradation during storage, while also controlling their release and extending stability and shelf life. This review critically examines recent literature on the microencapsulation of fixed oils, emphasizing wall materials, the spray-drying microencapsulation technique, its optimization, and impact on microencapsulation efficiency, technofunctional properties, biological activities, bioaccessibility, and oxidative stability. Furthermore, the application potential of spray-dried fixed oils capsules or powder particles in food systems is discussed, along with future research directions in the spray-drying microencapsulation of fixed oils.