Development, Proximate Composition, Energy Density, and Sensory Acceptability of Biscuits Fortified with Sentani Gudgeon (Oxyeleotris heterodon) Flour

Sentani gudgeon ( Oxyeleotris heterodon ), an underutilized native freshwater fish from Papua, Indonesia, has rarely been explored as a fortifying ingredient in baked products. This study developed biscuits fortified with Sentani gudgeon flour and evaluated their proximate composition, calculated energy density, and sensory acceptability as an early-stage food product development model. Fish flour prepared from skinned and deboned fish flesh was incorporated into a fish-fortification paste at 13, 15, or 17 g/100 g paste, corresponding to F1, F2, and F3, respectively. The paste was added at 20 g/100 g final biscuit formulation, giving approximately fish-flour levels of 2.6, 3.0, and 3.4 g/100 g product. Proximate composition was determined using AOAC methods, and sensory acceptability was assessed using a 9-point hedonic test and a preference-ranking test with 30 untrained adult panelists. The fish flour had a crude protein content of 88.26%, with low moisture and fat contents. Across the three formulation variants, increasing the fish-flour level in the fortification paste, together with simultaneous sugar reduction, was associated with lower biscuit moisture and carbohydrate contents and higher crude protein, crude fat, ash, and calculated energy values. F3 showed the most favorable overall performance, with the highest crude protein content, calculated energy value, overall acceptability score, and preference score. These findings provide preliminary product-development evidence that Sentani gudgeon flour can be incorporated into biscuits as a local fish-based fortifying ingredient while maintaining sensory acceptability within the tested adult panel and formulation range.