Valorization of Milkfish (Chanos chanos) Bone By-Products into Bone Powder and Milkfish Bone Floss Based on Nutritional Characterization and Calcium Contribution

The utilization of fish processing by-products represents an important strategy to improve production efficiency and support zero-waste principles. Milkfish (Chanos chanos) bone by-products, generated from deboned milkfish processing, have significant potential as a value-added food ingredient. This study aimed to characterize the nutritional composition of milkfish bone powder and milkfish bone floss products and to evaluate their potential calcium contribution to the recommended dietary allowance (RDA) for adults. Bone powder was produced through washing, boiling, oven drying at 60-70°C, grinding, and sieving (80 mesh). Bone floss was prepared through pre-boiling, high-pressure cooking (±121°C for ±2 hours), grinding with spices, and roasting until low moisture content was achieved. The study involved two product treatments, namely milkfish bone powder and milkfish bone floss. The nutritional composition of each product was determined using proximate analysis based on AOAC methods, including moisture, ash, protein, fat, and carbohydrate contents, with all analyses conducted in triplicate. Results showed that bone powder contained 3.52% moisture, 21.50% protein, 10.28% fat, 52.44% ash, and 12.26% carbohydrates, while milkfish bone floss contained 3.30% moisture, 20.82% protein, 23.32% fat, 25.88% ash, and 26.68% carbohydrates. The calculated energy values were approximately 227 kcal/100 g for bone powder and 400 kcal/100 g for bone floss using Atwater factors. Assuming that 30% of total ash represents calcium, bone powder is estimated to contain approximately 15,730 mg calcium per 100 g, theoretically exceeding 100% of the adult RDA (1000 mg/day) with a 10 g serving. Bone powder shows strong potential as a mineral fortification ingredient, while bone floss is suitable as a ready-to-eat high-energy product. These findings demonstrate that simple thermal processing can generate nutritionally competitive products from fish bone waste.