Studies on the Development and Evaluation of Zinc Microcapsules for Milk Fortification

Abstract

In the present study zinc microcapsules was prepared by using solvent evaporation newlinemethod, spray cooling method, and spray drying method. Microcapsules formed through newlinesolvent evaporation method were not spherical but concave in shape, and had sharp edges and newlinesurface cracks. Microcapsules was not formed through spray cooling method. In spray drying newlinemethod, zinc sulphate heptahydrate (ZnSO4.7H2O) and zinc picolinate (Zn(C6H4O2N)2) were newlineused as core materials, gum arabica was used as primary wall material along with newlinemaltodextrin, modified starch, whey protein isolate, soy protein isolate, pectin and sodium newlinealginate as filler materials. Zinc microcapsules were prepared using wall and core materials in newlinethe ratios of 10:1 and 20:1 with different inlet temperatures (140, 170, 200°C), with different newlinefeed flow rate (6 ml to 20 ml) and evaluated for their encapsulation efficiency (EE), newlineencapsulation yield (EY), storage stability (6 months) through zeta potentiality (ZP), shape newlinethrough SEM, size through particle analyser, identification and quantification of zinc through newlineEDX. Results revealed that, EE of 20:1 wall to core ratio was selected, through zeta newlinepotentiality test four combinations of microcapsules was selected namely, GA+WPI+ newlineZn(C6H4O2N)2, GA+WPI+ZnSO4.7H2O, GA+SPI+Zn(C6H4O2N)2, and GA+SPI + newlineZnSO4.7H2O and selected microcapsules was kept for storage studies for 6 months and every newline1 month interval zeta potentiality was evaluated. Based on EE, EY, and ZP, GA+WPI + newlineZnSO4.7H2O and GA+SPI+Zn(C6H4O2N)2 was selected for SEM and EDX analysis. The newlineparticles were almost spherical in shape with slight wrinkles and depressions on the surface. newlineEDX spectra identified and quantified the presence of zinc (0.59 and 0.79% in newlineGA+WPI+ZnSO4.7H2O and GA+SPI+Zn(C6H4O2N)2 respectively) content in microcapsules. newlineWhole cow milk (4.5% fat and 8.5 % SNF) was selected as a vehicle for fortification, newlineZnSO4.7H2O and Zn(C6H4O2N)2 salts and microcapsules at 10 mg, 15 mg and 20 mg newlineelemental zinc per 250 ml whole cow milk was fortified. Fortified mil