Physicochemical and sensory quality of mackerel fish ball formulated by dumbo catfish (Clarias gariepinus) protein isolate as a binder

Catfish is a freshwater fish with high protein content and productivity. However, its use is still limited. Food processing and formulation can be a solution to utilize catfish protein in fish-based products. This study investigated the physicochemical and sensory quality of mackerel fish balls (MFBs) formulated with catfish protein isolate (CPI) as a binder. The catfish protein was isolated using the pH-shifting method with extraction at pH 11 and precipitation at pH 5.5. The fish ball formulation contained mackerel crushed meat (MCM) and catfish protein isolate (CPI), with ratios of F1 (100:0), F2 (85:15), and F3 (70:30). The MFBs were also analysed for their physical (e.g., colour, water holding capacity (WHC), cooking loss, texture), proximate, and sensory properties. The results showed that the CPI had a high protein content (93.46% db), which followed the Codex Alimentarius standard. The addition of CPI had a significant effect on the colour, WHC, cooking loss, hardness, proximate composition, and sensory properties (colour, aroma, taste, texture, and overall attributes) of MFBs (p<0.05). The CPI improved WHC, hardness and protein content while reducing the cooking loss of MFBs. The MFBs with the ratio of MCM: CPI of 85:15 (F2) were the best formulation based on the hardness value, protein content, and sensory properties. The protein content of F2 increased by 6.89% from the control. CPI can be an additive ingredient in highly nutritious fish-based products with good physical and sensory properties.