Influence of Process Conditions on the Physicochemical Properties of Pequi Powder Produced by Spray Drying

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 degrees 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 14.3g adsorved water/100g solids), process yield (25.8 to 56.1%), water activity (0.07 to 0.17), vitamin C (113.0 to 306.6mg ascorbic acid/g pequi solids), and carotenoids content (10.9 to 74.3mg 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.