TITLE:
Microstructure of Annona muricata L. Leaves Extract Microcapsules Linked to Physical and Chemical Characteristics
AUTHORS:
Oscar Jordán-Suárez, Patricia Glorio-Paulet, Leslie Vidal
KEYWORDS:
Soursop, Microencapsulation, Microstructure, Spray Drying, Encapsulants
JOURNAL NAME:
Journal of Encapsulation and Adsorption Sciences,
Vol.8 No.3,
September
25,
2018
ABSTRACT: Microstructure is closely related to techno-functional properties in
microencapsulated powders intended to protect bioactive compounds. Soursop
leaves provide phytochemicals that need to be protected to ensure their
functionality. This investigation aimed to study the microstructure of
microcapsules containing soursop leaves extract and its linkage with physical
and chemical characteristics of the resulting powder. Microcapsules were
prepared by spray drying using gum Arabic and maltodextrin as encapsulating
agents at 5 and 10%. Powders were characterized by scanning electron
microscopy, particle size analysis, solubility, infrared spectroscopy and
encapsulation efficiency. Microphotographs showed spherical shape particles
ranging from 0.25 to 13.87 μm, where the particles morphology depended on the
concentration and the type of the encapsulant used. At higher concentration of
encapsulant, there was an increase in the sphericity, integrity, size, and
surface smoothness of particles. This relationship was inverse for solubility
in treatments with gum Arabic. The extract encapsulation was confirmed by
Fourier Transform infrared spectroscopy and encapsulation efficiency index,
revealing that the treatment with maltodextrin at 10% showed a better
capability for entrapment (72.12%). The results evidence that microstructure of
microcapsules is closely linked to the type and concentration of encapsulant,
which in turn determine the physical and chemical characteristics of powders
intended for instant drinks solubility and entrapping soursop bioactive
compounds.