Application of Recombinant Chum Salmon Cystatin to Alaska Pollock (Theragra chalcogramma) Surimi to Prevent Gel Weakening

• Published in: Journal of food science 2007-06, Vol.72 (5), p.C294-C299
• Main Authors: Li, D.K, Lin, H, Kim, S.M
• Format: Article
• Language: English
• Subjects: acidity; Alaska pollock surimi; Animals; Biological and medical sciences; cathepsins; Cathepsins - antagonists & inhibitors; Cathepsins - metabolism; Chromatography, Affinity - methods; Cystatins - chemistry; Cystatins - isolation & purification; Cystatins - pharmacology; cysteine; Cysteine Proteinase Inhibitors - chemistry; Cysteine Proteinase Inhibitors - isolation & purification; Cysteine Proteinase Inhibitors - pharmacology; Dose-Response Relationship, Drug; Enzymes; fish; Fish and seafood industries; Fish Products; food additives; food analysis; Food Handling - methods; Food industries; food quality; Food science; Fundamental and applied biological sciences. Psychology; gel strength; gel weakening; Gels; Hydrogen-Ion Concentration; inhibition; myosin heavy chains; Oncorhynchus keta; papain; Papain - antagonists & inhibitors; Papain - metabolism; protein degradation; proteinase inhibitors; Proteins; reaction inhibition; recombinant chum salmon cystatin; Recombinant Proteins - pharmacology; Saccharomyces cerevisiae; Salmon; Salmonidae; surimi; Temperature; Theragra chalcogramma; Yeast
• ISSN: 0022-1147; 1750-3841
• DOI: 10.1111/j.1750-3841.2007.00393.x

Recombinant chum salmon cystatin (RC) expressed in Saccharomyces cerevisiae was purified by His-select nickel affinity chromatography. The specific inhibitory activities of RC against papain and cathepsin L were 7.45 and 10.24 U/mg, respectively. RC was stable over pH 5.0 to 7.0 and at temperature below 65 °C. RC was used to prevent the gel weakening of Alaska pollock surimi. RC at 100 μg/g showed the highest inhibitory activity against the autolysis of surimi based on the analysis of TCA-soluble peptides. As the concentration of RC increased, both the breaking force and deformation of modori gel greatly increased (P < 0.05). The addition of RC resulted in less expressible drip, which coincided with the increase of whiteness. More myosin heavy chain (MHC) was retained as the addition of RC increased. Therefore, RC could prevent the degradation of proteins in Alaska pollock surimi and was better than egg white (EW). Thus, RC could be applied to Alaska pollock surimi to prevent gel weakening and RC at 100 μg/g was the optimal concentration.