Acessibilidade / Reportar erro

Influence of wall materials on the microencapsulation of pequi oil by spray drying

Influência dos materiais de parede na microencapsulação de óleo de pequi através da secagem por atomização

Abstract

The aim of this study was to assess the influence of the wall materials on the microencapsulation of pequi oil. An emulsion containing pequi oil in the oil phase was microencapsulated by spray drying process at 120 °C using gum Arabic, maltodextrin, or a 25:75 (w/w) mixture of gum Arabic and maltodextrin as wall material. The emulsions were characterized for droplet size, Polydispersity Index (PDI), and zeta potential. Pequi oil microparticles were analyzed for moisture content, water activity, wettability, encapsulation efficiency, antioxidant capacity, and color. Ultrastructural examination was performed by Scanning Electron Microscopy (SEM). The Droplet Size Distribution (DSD) of the emulsions exhibited a relatively wide size distribution (2.67 to 8.96 μm) and high PDI (> 0.3). Smooth microparticles with high encapsulation efficiency (79.17% to 84.20%), and good antioxidant capacity (28.20 to 28.71 μmol Trolox equivalents/g dry extract) were obtained. Microparticles prepared using gum Arabic as wall material had higher antioxidant capacity than that prepared with maltodextrin. All microparticles had satisfactory encapsulation efficiency, water activity, moisture content, and wettability. These results indicate that pequi oil microparticles have characteristics that can contribute to good stability during storage and handling of encapsulated oil. Therefore, pequi oil can be successfully encapsulated by spray drying using gum Arabic, maltodextrin, or 25:75 (w/w) mixture of gum Arabic and maltodextrin as wall materials, but the physicochemical properties of microparticles vary with wall material composition.

Keywords:
Caryocar brasiliense; Pulverization; Encapsulating agents; Characterization; Morphology; Microparticle

Instituto de Tecnologia de Alimentos - ITAL Av. Brasil, 2880, 13070-178 Campinas - SP / Brasil, Tel 55 19 3743-1762 - Campinas - SP - Brazil
E-mail: bjftsec@ital.sp.gov.br