A review of the progress in enzymatic concentration and microencapsulation of omega-3 rich oil from fish and microbial sources

Abstract

Technology continues to evolve for the concentration and stabilisation of omega-3 fatty acids for delivery into food and beverage products. The use of lipases for selective concentration of EPA and DHA, or for re-esterification reactions, is important in the production of omega-3 concentrates. Enzymatic strategies require robust enzymes that can be immobilised and multiply re-used. Novel and mild processing methods are particularly important for providing oils with good sensory properties, which are required for successful use as functional food ingredients. Although in some cases good quality oils can be used directly in some foods, such as margarine, many foods require that microencapsulated and stabilised omega-3 oils be used. This is particularly important when the oils are preconcentrated. There are a number of industrially used microencapsulation methods, but the most widely used are complex coacervates and spray dried emulsions. Fish oil is still the most widely used source of long-chain omega-3 fatty acids for addition to food, although algal oil is the primary source of DHA for infant formula use in North America. Algal oil is still significantly more expensive than fish oil for most applications, although many groups are improving both the cost and quality of omega-3 oil from algal sources. In particular, Thraustochytrid and Schizochytrid strains are a promising source of both DHA and EPA, and with further improvement could be used to provide varying ratios of these omega-3 fats. In this short review we will describe some of the current research in omega-3 fat concentration and microencapsulation, with particular emphasis on the use of lipases for concentration and complex coacervation for microencapsulation.