From Waste to Worth: Upcycling Piscindustrial Remnants into Mineral-Rich Preparations

This study investigates the valorisation of piscindustrial by-products, specifically fishbones from mackerel, horse-mackerel, and sardines, as sustainable sources of multi-mineral ingredients (MMIs) for future dietary supplementation. Ground fishbone powders were first analysed for moisture content and total ash to establish baseline composition. Following these preliminary assessments, the samples underwent mineral profiling using microwave plasma atomic emission spectroscopy (MP-AES), enabling quantification of calcium, phosphorus, magnesium, iron, zinc, sodium, potassium, copper, lead, cadmium, selenium, chromium, tin, manganese, and mercury. All three species yielded high concentrations of essential minerals, supporting their relevance as upcycled nutritional resources. A sardine-based capsule formulation was developed and compared with a commercial calcium supplement through 240 min dissolution testing. While calcium release values differed significantly from 75 min onward, both formulations exhibited similar dissolution profile shapes, despite differing dosage forms. Statistical analysis confirmed time- and formulation-dependent effects, with the sardine capsule demonstrating enhanced calcium bioaccessibility in later phases (95.26 ± 10.11 vs. 78.79 ± 5.39 mg). This work contributes to the advancement of the United Nations Sustainable Development Goals (SDGs), particularly SDG 3, SDG 12, and SDG 14. By transforming marine waste into health-promoting ingredients, and enabling revenue streams for ocean-cleaning charities, this initiative exemplifies circular innovation at the interface of nutrition, sustainability, and marine stewardship.