Freeze-drying microencapsulation of turmeric (Curcuma longa l.) using an amorphous matrix of maltodextrin, modified cassava flour and skim milk

This study aimed to evaluate the effect of freeze-drying microencapsulation of turmeric (Curcuma longa L.) assessing the influence of wall materials on microstructure characteristics, physicochemical composition, phytochemical, antioxidant properties, and in vitro release studies of turmeric microcapsules. The following four different samples were created: turmeric control (T0), turmeric in an amorphous matrix of maltodextrin (T1), turmeric in an amorphous matrix of modified cassava flour (T2), and turmeric in an amorphous matrix of skim milk (T3). The optimal treatment process was freeze-drying microencapsulation of turmeric polyphenols in an amorphous matrix of maltodextrin (T1), since it enabled high bioactive compounds with low values of moisture, water activity (aw), and curcumin release. Maltodextrin as a coating material in turmeric affected the increased level of yield, encapsulation efficiency, and microcapsule solubility. For instance, it showed a positive effect on the value of the total phenolic content, total flavonoid content, total tannin content, ascorbic acid, and consequently led to higher antioxidant activity. Turmeric (Curcuma longa L.) with the addition of maltodextrin can be used as a natural antioxidant compound and natural colorant for food products. © 2020, Galati University Press. All rights reserved.