Microencapsulation of yerba mate extract by spray-drying technique: Impact of polysaccharide mixtures on powder characteristics

Abstract

This study investigates the microencapsulation of yerba mate (YM) polyphenols using spray drying, employing β-cyclodextrin (β-CD), and binary and ternary mixtures of β-CD with maltodextrin (MD) and gum arabic (GA) as wall materials. Although MD and GA have been widely used for encapsulating plant extracts, β-CD has not yet been applied in spray-dried YM formulations. The wall materials significantly influenced key physicochemical properties of the microcapsules, including dissolution time (42.5–148.3 s), encapsulation efficiency (24.5–96.9 %), colorimetric attributes, total phenolic content (24–42 mg gallic acid equivalents/g YM powder), and antioxidant capacity (DPPH•: 80–290 μmol Trolox equivalents (TE)/g; ABTS•+: 160–270 μmol TE/g). Fourier-transform infrared spectroscopy confirmed the protective role of the wall materials, while morphological analysis revealed spherical microcapsules with irregular surfaces and diameters ranging from 3 to 6 μm. Furthermore, thermogravimetric analysis and differential scanning calorimetry demonstrated enhanced thermal stability for YM powders encapsulated with β-CD/MD and β-CD/MD/GA mixtures. These findings contribute novel insights into the potential of β-CD-based wall systems for the stabilization and functionalization of YM bioactives, providing a basis for the development of natural antioxidant ingredients in the food industry.