Valorization of bio-waste eggshell as a viable source of dietary calcium for confectionery products

The market of innovative foods is developing very dynamically and consumers are paying increasingly more attention to the health properties of the food offered. In addition, many studies on food consumption indicate a deficiency of minerals in the diet and experts suggest that the consumption of fortified functional foods in a selected group of consumers may contribute to the improvement of their health and quality of life.

The aim of the work was to present the possibility of using bio-waste eggshell as a source of calcium in designing confectionery products. A snack with high calcium (0.567 g Ca kg^-1 of product) and fiber (11.44 g kg^-1 of product) content and potentially high calcium bioavailability was prepared. The results of the sensory expert-based assessment indicate a high (6-7 conventional units) overall sensory quality (OSQ) of the four flavor versions of the product during up to 3 months storage. In order to accurately illustrate the effect of storage time on the quality of the samples, texture analysis was carried out and the presented results indicate low correlations (r = -0.5554; r = -0.1494) between instrumentally measured hardness and sensory attribute of crispness, as well as hardness and OSQ, respectively.

It is possible to reuse bio-waste eggshells as a calcium-fortifying substance for food design. The addition of powdered eggshells to food is an interesting direction, both for nutritional reasons (high concentration of calcium and optimal bioavailability) and also for environmental protection (reduction of post-production waste). © 2021 Society of Chemical Industry.