Utilization of eggshell waste in calcium-fortified foods and other industrial applications: A review

Greater consumption and utilization of chicken eggs worldwide prompts an expanded amount disposed of egg waste, mainly eggshell and eggshell membrane. The significant challenge with the generation of these massive waste products is the environmental impact. From an industrial point of view, when the production of chicken eggs tempts to rise, the quantity of eggshell residue is also increased. Being rich in organic and inorganic compounds, the eggshell wastes, which are primarily considered waste and of no value, could be utilized in various forms. In this review, information about the potential of eggshell waste to be converted into a bioavailable source of calcium for food fortification is reviewed. Its potential applications in other fields such as pharmaceuticals and agriculture were discussed. In addition to this, several eggshell calcium-based novel fortified products were also reviewed. Key findings and conclusions: Bioavailable salts can be used to fortify food products like cakes, yogurt, sausages, biscuits, and coffee. Besides, eggshells can be used as soil enhancers and also as animal feed. Based on this literature review, cheaply available and easier to extract eggshell calcium can provide an ideal alternative source of natural calcium in an environmentally safe way. All the products and processes suggested in this paper present high economic, health, and environmental benefits.