Microencapsulation of Calcium Derived from Eggshell Powder Utilizing a Combination of Coating Materials

Microencapsulation is a proficient method for safeguarding bioactive chemicals and enhancing their stability during the production and storage of food products. This study sought to identify the optimal ratio of gum Arabic (GA) and rice starch (RS) as coating agents for producing calcium microcapsules with improved retention and physicochemical stability. A Completely Randomized Design (CRD) was utilized, comprising seven formulations with varying chicken egg shell powder (ESP) and coating ratios (GA: RS, w/w): P1 (1:0:0), P2 (1:0.5:0), P3 (1:1:0), P4 (1:0:0.5), P5 (1:0:1), P6 (1:0.5:0.5), and P7 (1:1:1), employing 10 g of chicken shell powder as the calcium source. Each treatment was duplicated three times, producing 21 experimental units. The findings indicated that the coating composition considerably influenced product yield (16.47–37.97%), moisture content (3.00–6.16%), pH (8.01–8.48), solubility (7.95–22.62%), and calcium content (15.43–25.57%). The maximum calcium retention (25.57%) was observed in P6, with a formulation coating ratio of 1:0.5:0.5 (ESP:GA:RS, w/w), indicating that an optimal encapsulation efficiency was achieved with a balanced mixture of Gum Arabic and rice starch. This synergy improved the physicochemical stability, water solubility, and calcium retention of the microcapsules after freeze-drying. The research validates that combining the emulsifying and film-forming properties of Gum Arabic with the structural integrity of rice starch produces an efficient encapsulation matrix. These findings highlight the potential of GA–RS microcapsules as an effective calcium-delivery technology for fortified beverages, baked goods, dairy products, and nutraceutical supplements.