Effect of wall components on characteristics of natural canthaxanthin microencapsulated using spray-drying

Canthaxanthin is a ketocarotenoid used in pharmaceutical، medical، cosmetic، fishery، poultry، and food industries. The restriction of synthetic carotenoids in food industries has led to the development of canthaxanthin from biological resources. Canthaxanthin is a highly unsaturated molecule that is susceptible to environmental conditions. Spray drying microencapsulation is a technique to protect carotenoids from adverse environmental conditions and was used in this study to increase the stability of microbial canthaxanthin. The objective of the study was to compare the effects of polysaccharides used as wall materials on the characteristics and stability of microencapsulated canthaxanthin. A strain of the bacterium Dietzia natronolimnaea HS-1 was used as the source of canthaxanthin. Gum Arabic (GA)، maltodexterin (MD)، and pullulan (PL) were used as wall materials for microencapsulation of canthaxanthin using spray drying. The effect of adding MD and PL to GA as wall materials on the characteristics and stability of the microcapsules produced were investigated. It was shown that the type of wall did not affect the moisture and water activity of the microcapsules، but did influence other characteristics. Microcapsules made from GA and PL were smaller in size and contained less surface carotenoid. Microcapsules produced with MD were largest in size and showed the least microencapsulation efficiency. The results also showed that the degradation of microencapsulated canthaxanthin using GA and PL proceeded more slowly than did that using MD over 6 mo of storage. The results of this study found that GA and PL are potential wall materials for the encapsulation of canthaxanthin using the spray-drying method.