Effect of fortified calcium compounds from oyster shell on the quality of tapioca pearls

Abstract

This study aimed to determine the effect of calcium fortification from dried oyster shells (DOS) and calcined oyster shells (COS) at concentrations of 2, 4 and 6 %(w/w) on physical and chemical properties of tapioca pearls. The results showed that the optimal cooking time of TP-COS decreased compared to TP-DOS and TP (control). The TP-DOS and TP-COS exhibited a remaining calcium content ranging from 8.39 to 41.03 mg/g. During seven days of refrigerated storage, TP-COS showed delayed hardness along with decreases in both the enthalpy of gelatinization and retrogradation. The functional groups observed in TP-DOS and TP-COS showed varying intensities compared to TP. Morphology images depicted the distribution of DOS and COS within tapioca pearls, revealing that TP-DOS and TP-COS possessed a denser and more compact structure. The results suggest that COS fortification could improve the nutritional value and delay the change in the texture of tapioca pearls after storage.