Significant fat reduction in deep-fried kamaboko by fish protein hydrolysates derived from common carp (Cyprinus carpio)

BACKGROUND: To evaluate their fat reduction effect, common carp fish protein hydrolysates (FPH) were made using four methods: the conventional enzymatic process, a microwave-intensified enzymatic process, the conventional alkaline hydrolysis process, and a microwave-intensified alkaline hydrolysis process. 

RESULTS: The efficiency of protein extraction was significantly enhanced by microwave intensification. The oil-holding capacities of FPH produced by these four processes were all lower than that of raw fish protein. The water-holding capacities of FPH produced by these four processes were all higher than that of raw fish protein. The FPH from the four processes and raw fish protein were used in the preparation of deep-fried kamaboko. The fat content of deep-fried kamaboko was drastically reduced from approximately 160 g kg⁻¹ to about 50 g kg⁻¹ by replacing 20 g kg⁻¹ fish mince with FPH, regardless of the process. Texture profile analysis (TPA) of deep-fried kamaboko found no significant difference in hardness and brittleness among all the deep-fried kamaboko samples. The similar interior protein cross-linking micro-structure of all these samples further explained the TPA finding. 

CONCLUSION: With the involvement of FPH in the formulation, the fat content of deep-fried kamaboko can be significantly reduced from approximately 160 to 50 g kg⁻¹ , without a change in its texture.