Encapsulation Techniques for Food Purposes

Demand for functional food that offers health benefits beyond basic nutrition is increasing. However, challenges in development of nutritionally-enriched food are often limiting its wider production. Generally, the bioactivity losses during food processing, the immiscibility of active ingredients with the food matrix, the change in sensorial properties of the food products and the low bioavailability of some of the active ingredients are challenges faced when developing functional foods. This chapter reviews the state-of-the-art in microencapsulation techniques that can help to overcome aforementioned difficulties. Microencapsulation of sensitive food ingredients provides not only protection against detrimental effects of temperature, light, pH or oxygen, but also delayed/controlled release of actives, masking of unpleasant flavors and it can impact food structure. The most applicable microencapsulation techniques for food purposes are described, and the main advantages and current challenges, as well as the latest advances in application of these technologies are discussed. The microencapsulation techniques included in this chapter are spray and freeze drying, electrospraying, spray-chilling and spray-cooling, emulsification techniques, fluidized-bed coating, supercritical fluid techniques, production of microgels, coacervation, liposomal techniques and inclusion complexation.