Chapter 10 - Bioencapsulation for food additives

Abstract

Chemical preservatives such as sodium benzoate, sodium nitrite, and sulfur dioxide are generally used to prevent nutritional and sensory losses in foods caused by microbiological, enzymatic, or chemical changes. However, in recent years, consumers have interested in food products preserved with natural additives, since the accumulation of synthetic preservatives in the tissue can be harmful to health. In addition, consumer demands for foods protected with antimicrobial substances found in plants, animals, and microorganisms are increasing. Various studies have been conducted to control the microbial growth of food products, especially seafood and meat products, using lactic acid bacteria and their bacteriocins. However, losses in probiotic viability occur during food processing and storage due to various kinds of environmental stress including temperature, acid, salt, low pH, nutrient reduction, and exposure to osmotic and oxidative stress in product matrices. Encapsulation of probiotic bacteria for example L. rhamnosus and L. reuteri is recommended to overcome these problems and protect food and cells in unfavorable conditions. The encapsulation process is applied in the food industry to integrate bioactive ingredients into several food types, preserve them from unwanted environmental situations and enhance the shelf life of the product. These bioactive additives are completely surrounded by a wall material, thus removing unfavorable properties from the original component. Although various methods have been improved to nano and microencapsulate food constituents, spray drying is the most preferred technology in the food sector due to its low cost and existing equipment. Spray drying is generally used in the food industry to reduce the water content and water activity of products, to provide microbiological stability, to eliminate the risk of chemical and/or biological degradation, to decrease storage and shipping costs, and to get a product with specific features such as instant solubility. Also, electrospraying and electrospinning techniques in nanoencapsulation of the mentioned materials above are currently gaining much more importance in the food industry and food science.