Crotalaria longirostrata (chipilin) leaves contain phenolic compounds with antioxidant activity. These phenolic compounds, however, could easily degrade after extraction. Microencapsulation is a possible solution for avoiding this degradation. Frequently, microencapsulation is carried out using conventional encapsulating agents. The aim of this work was to evaluate the effect of several non-conventional encapsulating agents on microencapsulation by spray drying of phenolic compounds from chipilin, stability and release of phenolic compounds were also studied. Maltodextrin (MD), gum Arabic (GA), soy protein (SP), cocoa shell pectin (CSP), and protein (PC), as well as the gum (GC) of Cajanus cajan seeds were used. Different blends of these matrixes containing phenolic compounds from chipilin leaves were spray dried at 120 °C. After drying, the yield and microencapsulation efficiency were determined. All results were analyzed by an ANOVA test (p < 0.05). The release kinetics of phenolic compounds were modeled using zero, first-order, Higuchi and Korsmeyer-Peppas models. The R2 was calculated for each model. The blends of encapsulating agents allowed the formation of an efficient polymer matrix with yields between 46 and 64% and microencapsulation efficiency between 65 and 92%. Results show that maltodextrin with soy protein allowed the highest (92%) microencapsulation efficiency, although maltodextrin and cocoa shell pectin were more effective protective agents, showing greater stability. The Korsmeyer-Peppas model was the best in predicting the phenolic compounds release with R2 values higher than 98%. The stability time for microcapsules with MD-CSP was 8.88 years and 1.43 years at 4 °C and 30 °C, respectively.
Keywords: Cajanus cajan; Cocoa shell pectin; Crotalaria longirostrata extract; Gum of Cajanus cajan; Spray drying.
© Association of Food Scientists & Technologists (India) 2020.