Application of polymannosylated cystatin to surimi from roe-herring to prevent gel weakening.

A recombinant glycosylated cystatin with a polymannosyl chain was added to roe-herring surimi for preventing gel weakening due to autolysis during cooking. Proteolysis of myosin heavy chain in the surimi was effectively suppressed while cooking at 90 degrees C for 20 min after preincubation at 40 degrees C for 30 min. The glycosylation of cystatin improved the stability against heating as well as proteolysis by cathepsin D. This process markedly improved the texture of the cooked surimi gel with gel strength 2.5 times that of unglycosylated control cystatin.