Release kinetics in liquid medium of oregano essential oil microencapsulated by complex coacervation

• Grant number: 19/05085-0
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): June 01, 2019
• Effective date (End): May 31, 2021
• Field of knowledge: Agronomical Sciences - Food Science and Technology - Food Engineering
• Principal researcher: Vânia Regina Nicoletti Telis
• Grantee: Vítor Mathias Muneratto
• Home Institution: Instituto de Biociências, Letras e Ciências Exatas (IBILCE). Universidade Estadual Paulista (UNESP). Campus de São José do Rio Preto. São José do Rio Preto , SP, Brazil

Abstract

Oregano essential oil consists mainly of phenolic compounds with antimicrobial and antioxidant properties, which are significant in the food industries. Nevertheless, the essential oils have volatile compounds that can be degraded by the exposure to harmful levels of light, temperature and oxygen. Therefore, those bioactive molecules need to be protected from the environment conditions, which leads to the use of microencapsulation techniques. This method is widely used because it is capable to protect the core material and can also control the release pattern of the bioactive material in different mediums. Microencapsulation by complex coacervation is a relatively simple, low cost, high-efficient and traditional method based in the electrostatic interactions between charged proteins and polysaccharides with opposite charges. However, there are few studies investigating essential oil release kinetics, especially the ones focusing on the liberation medium characteristics and the parameters that could play the role of triggers. Thus, the present paper has the objective of studying the in vitro liberation of oregano essential oil encapsulated by complex coacervation, using Arabic gum and gelatin as wall materials. Moist and freeze-dried microcapsules will be evaluated in liquid medium with different ionic strength, temperatures and pH as well, in order to understand the effect of these parameters as release triggers.