Using biopolymer blends for shrimp feedstuff microencapsulation -: I.: Microcapsule particle size, morphology and microstructure

dA shrimp feedstuff was microencapsulated through spray drying using different biopolymer treatments as wall materials after a three component Simplex Centroid experimental design, employing wall material to feedstuff ratios of 2:1 and 3:1, and pH values of 4 and 8. The response surface methodology indicated that the three above mentioned variables affected the microcapsule particle size and microstructure, as evidenced by scanning electron microscopy. Predictive equations show that the factor that affected significantly the microcapsule particle size was the binary interactions among the biopolymers. The higher the wall material-feedstuff ratio the larger the microcapsule particle size. As pH varied from 4 to 8, the biopolymer adsorbed layers around the core material were more extended. All the resulting microcapsules were of the matrix type, in which the feedstuff microparticles were distributed within the solid wall material matrix. (C) 1999 Canadian Institute of Food Science and Technology. Published by Elsevier Science Ltd. All rights reserved.