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North Paciˆc krill Euphausia paciˆca has very low market value due to its small size and quick quality degradation. To add high value to the krill, the eŠect of isoelectric solubilization/precipitation using food additives to recover the krill protein was investigated. The krill protein could be solubilized by adding alkaline additives (K 2 CO 3 , Na 2 CO 3 , K 3 PO 4 or Na 3 PO 4 ) and precipitated by adding organic acids (citric acid, DL-malic acid, L-tartaric acid or acetic acid). The protein recovery yield was the highest when solubilized at 10.0 and precipitated at pH 4.0. In particular, the treatment using K 2 CO 3 and citric acid showed the highest protein recovery yield (58.8) which was higher than that of the control (NaOH and HCl treatment; 40.9). SDS-PAGE pattern, proximate composition, mineral composition and amino acid composition of the protein recovered by K 2 CO 3 and citric acid treatment were comparable to those of the control. From the above, it can be concluded that the isoelectric solubilization/precipitation using K 2 CO 3 and citric acid is eŠective to recover proteins from the krill.

North Paciˆc krill Euphausia paciˆca has very low commercial value in Japan due to its small size and high autolytic activity. To utilize the krill as a raw material of gel products, a new method to recover the krill protein by salt water treatment was investigated. The krill was homogenized with NaClaq (ˆnal conc. 4) and then diluted to 10 times (v/v) to obtain precipitate as recovered protein. Both Ca-ATPase and Mg-ATPase activities of the recovered protein were high. Thermal gels from the recovered krill protein were obtained when heated at 80

To utilize North Paciˆc krill Euphausia paciˆca as a raw material of gel products, protease inhibitors were used to suppress proteolysis during the krill protein recovery process to improve the thermal gel-forming ability of the recovered protein. The krill was homogenized with NaClaq (ˆnal conc. 4) and then diluted to 10 times (v/v) to obtain recovered protein. Intense autolysis including myosin heavy chain (MHC) degradation in the recovered protein was observed at the dehydration step and it was eŠectively suppressed in the presence of serine protease inhibitors such as 50 mmol/kg Benzamidine, 1.0 mg/g SBTI or 5 mmol/kg PMSF. The thermal gel-forming abili

To utilize blue shark Prionace glauca which is under-used resource, the effect of sodium alginate and calcium chloride on the gel property of the fish meat gel was investigated for improving its low gel-forming ability. Breaking stress of the fish meat gels was enhanced by adding more than 3％ sodium alginate and then immersing 1％ calcium chloride (aq). On the other hand, breaking deformation of the gels was decreased by the addition of sodium alginate and their physical properties were similar to those of abalone. SDS-PAGE patterns showed that protein polymerization in the gels depended on the concentration of sodium alginate. These results indicated that a new gel product having unique textures like abalone can be developed using blue shark meat with sodium alginate and calcium chloride.