Co-encapsulation of anthocyanins extracted from grape skins (Vitis vinifera var. Syrah) and α-tocopherol via spray drying

Abstract

The present study sought to characterize the microparticles obtained from the co-encapsulation of anthocyanins extracted from red grape skins and α-tocopherol via spray drying. Briefly, grape skin extract was homogenized with gum arabic, Tween 80, and different concentrations of α-tocopherol. Anthocyanin content, antioxidant activity, total phenolic content, α-tocopherol concentration, color, hygroscopicity, morphology, and the Fourier transform infrared spectroscopy (FTIR) results of each treatment were analyzed. The highest concentration of α-tocopherol led to the highest total phenolic content, and the lowest hygroscopicity and anthocyanin content. Intermediate concentrations of α-tocopherol resulted in an increased incidence of microparticles with smooth surface and elevated antioxidant activity. The FTIR spectra verified the efficacy of the process, showing characteristic bands of the co-encapsulated compounds. Overall, α-tocopherol concentrations between 1.5% and 2.0% (w/w) led to good powder properties (hygroscopicity, total phenolic content and antioxidant activity), generating further research interest to evaluate the use of α-tocopherol in foods.