Microencapsulation of myrtle berry anthocyanins: spray-dried maltodextrin-gum Arabic microcapsules with enhanced antioxidant stability and controlled release

Abstract

Myrtle berries contain phytochemicals and natural anthocyanins. However, despite their many health benefits, anthocyanins face stability challenges in food applications due to their sensitivity to environmental factors. The objective of this study was to determine the most effective wall material for microencapsulation myrtle berry extract (MBE) with combinations of gum Arabic (GA) and Inulin (IN) at five different ratios (GA/IN: 1/5, 1/2, 1/ 1, 2/1, 5/1). The microcapsules formulated with GA/IN (2/1) (F4) showed the highest encapsulation efficiency (97.8%). Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) confirmed the successful encapsulation of the extract. HPLC analysis results showed that delphinidin-3-glucoside and other anthocyanins were not degraded after encapsulation. Among all formulations, F4 demonstrated the smallest decline in antioxidant activity compared to the other treatments after 60 days of storage. The retention of anthocyanins in five formulations storage at 40 ◦C ranged from 87.1% to 95.9%. The in vitro release profile further demonstrated that the encapsulated anthocyanins had a more controlled release compared with the crude extract. Overall, the findings support the concept that microencapsulation can enhance the stability of anthocyanins.