Fortification of chocolate using Moringa oleifera extract encapsulated in microemulsions

The aim of the present study was to evaluate the physical and antioxidant properties of microemulsions containing Moringa oleifera leaf extract (MLE) produced by the means of a deep eutectic solvent. Selected microemulsions containing MLE were incorporated in chocolate products to enrich them. Their color properties including CIE L*, a*, b* parameters and whitening index (WI) along with DPPH radical scavenging activity were assessed during a period of 8 months. The antioxidant activity of microemulsions depended on the oil phase used, while it was unaffected by the concentration of MLE. Samples prepared with soybean oil as oil phase containing MLE presented the highest radical inhibition percentage (I% = 26.8–27.8%). Coconut microemulsions were finally incorporated at 2 and 4% w/w concentration into chocolate products, as coconut oil is a known cocoa butter substitute. Although the incorporation of MLE microemulsions did not affect the color properties of most of the chocolates, enriched products did not exhibit superior antioxidant activity compared to control samples.