Comparison of different degreasing technique of Pneumatophorus japonicus

The study focuses on the comparison between degreasing technique of chub mackerel( Pneumatophorus j aponicus) fillet and surimi w ith alkaline lipase hydrolysis and physicochemical method ( bleaching and pressure) respectively . These research result s indicated the degreasing of physicochemical method ( w ith 11. 01 of lipid residue rate based on dry weight, the below is as the same) is superior to enzyme hydrolysis ( with 19. 48% of lipid residue rate) for chub mackerel f illets, but on the contrary the enzyme hydrolysis ( with 3. 49% of lipid residue rate) is much superior to the physicochemical method ( with 7. 52% of lipid residue rate ) for chub mackerel surimi. The optimum conditions of enzyme hydrolysis are selected as follows pH from 8. 7 to 9. 2; temperature at 32 e ; alkaline enzyme solution w ith a lipase activity of 40U#mL- 1; the ratio between enzyme solut ion and surimi to be 5: 1; time of enzyme hydrolysis for 50 min. The results showed that the lipid residue rate of Chub mackerel surimi is less than 4% by using alkaline lipase and about 8% by using physicochemical method respectively under the above enzyme hydrolysis. The residual lipid rate of f illet is dif ficult to reach below 10% either by alkaline lipase or by physicochemical method.