Obtaining pequi pulp and babassu coconut milk microencapsulated by spray drying

Author(s)

Audirene Amorim Santana

• Document type: Doctoral Thesis
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Faculdade de Engenharia Agrícola
• Defense date: 2013-07-02

Examining board members

Kil Jin Park; Cristina Yoshie Takeiti; Wanderley Pereira Oliveira; Flavio Luis Schmidt; Rael Augustus de Oliveira

• Advisor: Kil Jin Park; Louise Emy Kurozawa

Abstract

Pequi (Caryocar brasiliense Camb), fruit rich in oil, protein and carotenoids, is grown throughout the Brazilian Cerrado. Another product found in this region is the babassu (Orbignya phalerata, Mart.), which is one of the most important representatives of Brazilian palms. It is obtained the almond that has a nice flavor and nutritional value recognized. Drying of these products is set up between the various technologies for its use. A widely used kind of drying for the processing of a product in a fluid state to solid in powder form is spray drying. The objective of this research was to obtain pequi pulp and babassu coconut milk powder microencapsulated with maltodextrin DE10, gum Arabic and dextrin through the process of spray drying. Initially, centesimal characterization was made of raw materials and preliminary tests for some powders formulated with different agents encapsulants. From data obtained in preliminary tests for pequi pulp was performed three central composite rotatable design (CCRD with 17 assays), and the moisture content, hygroscopicity, process yield, vitamin C, Aw and total carotenoids were evaluated. For babassu coconut milk three CCRD (11 test) were evaluated to verify the effect of inlet air temperature and encapsulating agent concentration, on the responses moisture content, hygroscopicity, process yield, Aw and lipid oxidation. Vitamin C and the yield obtained for particles of pequi pulp were very similar for the three experimental matrix studied, but the particles with dextrin had higher levels of total carotenoids. For capsules babassu coconut milk, dextrin showed less oxidative conservation than other encapsulants. Through these experimental, the optimized conditions of the process were obtained. The powders obtained under these conditions were evaluated for the real and apparent density, porosity, particle size distribution, wettability, scanning electron microscopy, critical storage conditions through the analysis of sorption isotherms and glass transition temperature and study of stability through analyzes of total carotenoids, lipid oxidation, color and antioxidants. The greatest mean diameter was obtained for powders of pequi pulp and babassu coconut milk microencapsulated with dextrin and consequently had the shortest time wetting. The powders of pequi pulp and babassu coconut milk with gum Arabic, maltodextrin and dextrin were presented heterogeneous size. The sorption isotherms of the pulp pequi and babassu coconut milk microencapsulated with different encapsulating agents showed a good fit to the BET model to two parameters. The critical Aw for the powders pequi pulp was 0.62, since, above this value powder shows physical transformations as collapse, stickiness and caking. As for the babassu coconut milk powder the critical value of Aw was 0.96, but the critical moisture could not be determined. In the analyzes of stable capsules pequi pulp and babassu coconut milk, gum Arabic is more efficient encapsulation and protection in the presence of oxygen, which may be fixed in future studies for these products (AU)