Adaptação de aerógrafo para microencapsulação de óleo essencial de laranja doce por gelificação iônica

Abstract

Sweet orange essential oil has compounds with antioxidant, anti-inflammatory, gastroprotective, and anticancer properties and can be used as a food preservative. Microencapsulation is the process of forming microparticles in order to physically and chemically protect a chemical compound. Since essential oils are susceptible to degradation in contact with oxygen and ultraviolet light, microencapsulation can aid in their preservation. The advantages of microencapsulation by ionic gelation are that no toxic compounds are used, making it possible to use it in foods, drugs, and cosmetics, as well as its low cost. The formation of smaller microcapsules is desirable to improve the organoleptic characteristics of foods and drugs, as well as to increase the total surface area of the active ingredient. The airbrush is a tool that uses compressed air to atomize a liquid, usually used for artistic purposes such as oil paintings. The present work aims to adapt an airbrush to allow its use in the confection of sweet orange essential oil microcapsules by means of ionic gelation. To verify the effectiveness of the equipment, the conventional and reverse ionic gelation microencapsulation methods were tested. Emulsions were made with 20%, 40%, 60% and 80% essential oil in sodium alginate solution, and it was observed that the viscosity and stability of the emulsions increased proportionally to the essential oil concentration. It was observed that the airbrush without modification was not able to atomize the emulsions due to their high viscosity, só a proposal to modify the airbrush by using a peristaltic pump to pressurize the upper cavity was set up. The proposal was successful, and microcapsules with an average diameter of 20 to 30 µm could be obtained for all emulsions tested in the conventional ionic gelation process, the reverse method did not result in capsules. No statistically relevant differences were observed in the morphology of microcapsules made with different concentrations of essential oil.