Quality control in the production of microencapsulated natural antioxidants from Clove (Syzygium aromaticum)

In the present work, powdered lipid formulations encapsulating natural antioxidants from Clove (Syzygium aromaticum) were prepared by spray drying and freeze drying. The microencapsulation of eugenol (EU) and eugenyl acetate (EA), the main phenolics compounds from clove, is justified by their volatility and poor water solubility. Lipid formulations have gain especial attention as delivery systems of plant-derived compounds due to their encapsulation efficiency, stability and modification of solubility. The formulation developed in this work was composed by a mixture of the solid lipid glyceryl behenate (Compritol 888 ATO), the liquid lipid buriti oil (Mauritia flexuosa), a surfactant Poloxamer 188 (Kolliphor® P 188) and Maltodextrin DE10 as drying carrier. High Performance Liquid Chromatography (HPLC) was employed to monitor the concentration of EU and EA during the production process of the microcapsules, which involves the extraction process, preparation of the liquid formulation involving homogenization by ultrassound and the drying process. Results showed that the concentration of EU and EA was significantly higher in the powder obtained by freeze drying than the one obtained by spray drying, and the antioxidant activity was correlated with the concentration of those compounds. The main advantage of freeze drying over spray drying is that the losses of compounds was significantly lower, although it is a more expensive and time consuming process.