Utilization of cocoa pod husk (Theobroma cacao L.) for production of microencapsulated powder rich in alkaloids

Abstract

This study aimed to utilize cocoa pod husk (CPH) and various encapsulating materials (maltodextrin, gum Arabic, and chitosan) for production of microencapsulated powder rich in alkaloids. Physicochemical properties in terms of moisture content (MC), water activity (a_w), water soluble index (WSI), density and morphology, bioactive compounds including total alkaloids content (TAC), total phenolics content (TPC), total flavonoids content (TFC) and total saponins content (TSC), as well as antioxidant activity comprising ABTS/DPPH radical scavenging capacity (ARSC/DRSC) and ferric/cupric reducing antioxidant capacity (FRAP/CUPRAC) of powder rich in alkaloids from the CPH extract without and with microencapsulation were then analyzed and compared. The results showed that the MC and a_w of microencapsulated powders (4.78 to 5.88% and 0.46 to 0.51, respectively) were lower than those of powder without microencapsulation (9.64% and 0.54, respectively). Use of maltodextrin and gum Arabic (9:1 w/w) as the wall materials for microencapsulation of the CPH extract obtained the greatest levels of TPC, TFC, TSC, DRSC, FRAP and CUPRAC (14.91 mg GAE, 22.69 mg CE, 113.21 mg EE, 24.59, 2.92 and 92.68 mg TE per g dried sample, respectively), while use of 100% maltodextrin resulted in the maximum amounts of TAC and ARSC (646.96 mg AE/g dried sample and 36.27 mg TE/g dried sample, respectively). Based on the obtained results, the mixture of maltodextrin and gum Arabic (9:1 w/w) as the wall materials was recommended to microencapsulate the alkaloids-enriched CPH extract for potential application in the nutraceutical and functional food industries.