Microencapsulação do carvacrol na matriz de gelatina/goma arábica reticulada com transglutaminase via coacervação complexa

Abstract

Several studies have identified the potential for high bioactive interest in carvacrol. However, due to its volatility, it becomes susceptible to degradation and loss of its characteristics. In order to overcome these difficulties and make the application of carvacrol (CA) feasible, the bioactive was microencapsulated by complex coacervation, coating the particles with polymers. For this process, gelatin (GEL) and gum arabic (GA) biololymers were chosen as wall materials and transglutaminase (TGL) as cross-linking agent. Particles with different levels of carvacrol - 40% (2g CA), 50% (2.5g CA) and 60% (3g CA) w/w - were produced in relation to the biopolymers, in order to observe the behavior of the encapsulated bioactive. The microparticles produced at different concentrations of carvacrol were evaluated for morphology, chemical structure and thermal resistance. Regarding morphology, the samples showed spherical structure and better production behavior in the GA/GEL/2.5CA sample. The particle size varied according to the increase in bioactive concentration, in a range of 468 to 608 µm. However, GA/GEL/2.5CA sample presented larger diameter distributions. All samples presented chemical characteristics that identify the presence of the bioactive in the capsules, however, the GA/GEL/2.5CA sample presented greater intensity of the existence of carvacrol. By evaluating the particles for thermal resistance, it was found that the sample GA/GEL/2.5CA showed better behavior, increasing the temperature at the beginning of degradation from 68.5°C (pure compound) to 130.7°C. When this sample cross-linked, it was observed that the transglutaminase enzyme slowed down the degradation of carvacrol by 20°C compared to the sample without cross-linking.