Abstract
Microencapsulation of extract pequi pulp by spray drying, using Arabic gum as a microencapsulating agent, was studied. Tween 80 was used as a secondary emulsifier. A factorial design was conducted with the following independent variables: inlet air temperature (140 to 200°C), surfactant concentration Tween 80 (0 to 5%), and microencapsulating agent concentration (10 to 20%) on the responses; moisture content (0.3 to 1.9%), hygroscopicity (10.7 to 14.3 g adsorved water/100 g solids), process yield (25.8 to 56.1%), water activity (0.07 to 0.17), vitamin C (113.0 to 306.6 mg ascorbic acid/g pequi solids), and carotenoids content (10.9 to 74.3 mg carotenoids/g pequi solids). Only powder moisture content, hygroscopicity, water activity, and vitamin C content were statistically influenced by independent variables. Spray drying was optimized for maximum vitamin C and carotenoids content and minimal water content and hygroscopicity. Powder obtained under optimum conditions was characterized as to particle morphology, bulk, absolute density, and particle size distribution.
ACKNOWLEDGMENTS
The authors acknowledge the Foundation of Research Support of São Paulo–FAPESP (process number 2009/54170-9) and the Faculty of Agricultural Engineering of the University of Campinas for financial support.
Notes
AOAC = Association of Analytical Chemists.
N.S. = non-significant at p > 0.10.