Encapsulação do óleo essencial de pimenta preta (Piper nigrum L.) por coacervação complexa, utilizando proteínas e alginato de sódio como materiais de parede

Abstract

The black pepper (Piper nigrum L.) essential oil (EO) is a rich source of biologically active compounds (e.g.terpenes) and your applicability as a food additive has been the subject of several studies due to the antimicrobial and antioxidant activity of these compounds. Terpenes, however, are volatile and when exposed to certain conditions (high temperatures, light, low pH and gastrointestinal fluids) can reduce their biological potential and, in this sense, microencapsulation is an alternative way to the conserve EOs properties and their components. Among the microencapsulation methods, the complex coacervation method has advantages such as low concentrations of the wall materials, high encapsulation efficiency, and a variety of biopolymers that can be applied as wall materials. The aim of the present study was to characterize and evaluate the stability of black pepper EO encapsulated by complex coacervation using different biopolymers wall materials. The biopolymers and cross-linking agents used were effective in the protection of the EO, presented high encapsulation efficiency and preserved their main terpenes. Capsules formed by lactoferrin/sodium alginate and β-lactoglobulin/sodium alginate preserved the EO when exposed to simulated oral and gastric conditions in vitro. In simulated aqueous foods, the EO release was lower from β-lactoglobulin/sodium alginate microcapsules, and the EO release was by Fickian diffusion according to the Rigger-Peppas model. The obtained results suggest that the wall materials used were efficient and could be applied to encapsulate new active ingredients.