Microencapsulation and antimicrobial activity of carvacrol in a pectin-alginate matrix

Carvacrol is a natural phenolic compound that has received great attention for its high antimicrobial activity. However, the applications of this compound are limited due to its high volatility and low water solubility. In this research, the use of food grade polymers for microencapsulation of carvacrol in a pectin-alginate matrix using a spray drying method was studied. The physical properties, encapsulation efficiency, stability, and the microstructure of the microcapsules were analyzed as well as the products' antimicrobial and antioxidant properties. The microcapsules were regularly spherical particles with 4.51% moisture content, 0.33 g cm(-3) bulk density, 4.55 min wettability, and a hygroscopicity of 34.44 g 100 g(-1). The microcapsules also showed high encapsulation efficiency (76.98%) and stability. The microencapsulation process did not significantly affect the antimicrobial activity against Escherichia coli K12 (minimum inhibitory concentration (MIC) = 0.25 mg mL(-1)) and antioxidant activity (DPPH percentage inhibition (PI) = 89.96%) of carvacrol. The results indicated that the carvacrol microcapsule product can potentially be used as a controlled-release decontaminator in food and nutraceutical processing industries.