Waste utilization and optimization of calamansi peels: a formulation study on biodegradable microbeads

One environmental challenge posed by agricultural waste in the Philippines can be mitigated by converting fruit peel waste into valuable cellulose-derived microbeads. Utilizing the ionic gelation technique, this study introduces a sustainable, “waste-to-value” innovation designed to replace synthetic microplastics in the cosmetic industry. The resulting microbeads are characterized by a yellowish-green, spherical morphology with a standardized particle size of 850 micrometers, well within the functional limit for exfoliants, and an excellent flowability rating indicated by a 26.55° angle of repose. When incorporated into formulations, the microbeads maintained high structural stability; the resulting hand sanitizer had a pH of 3.55, while the facial gel exfoliant had a pH of 7.6, demonstrating excellent homogeneity and foam stability. By successfully validating these bio-based alternatives, the study highlights a circular-economy approach that mitigates food-processing waste while providing eco-friendly, high-performance materials for the global personal care sector.