Encapsulation Systems in the Food Industry

Abstract

Encapsulation is a useful tool to improve the delivery of bioactive and living cells into foods. Encapsulation aims to preserve the stability of the active compounds during processing and storage and to prevent undesirable interactions with the food matrix. In addition, encapsulation may be used to immobilise cells or enzymes in food processing applications, such as fermentation processes and metabolite production processes. This chapter aims to provide an overview of commonly used processes to encapsulate food actives and numerous reasons for employing encapsulation technologies. The most widely used materials for the design of protective shells of encapsulates are presented (polysaccharides, their derivatives, plant exudates, marine extracts, proteins and lipids) with a special focus on requirements such as food-grade purity, biodegradability and the ability to form a barrier between the internal phase and its surroundings. A number of techniques are available for encapsulation in the food industry. Spray drying is the most extensively applied encapsulation technique on an industrial scale; the other encapsulates are prepared by, for example, spray-chilling, freeze-drying, melt extrusion, and melt injection.