Effect of Surimi Ratio and External Additives on the Gel Properties of Composite Antarctic krill Surimi

Antarctic krill surimi was made by method of isoelectric precipitation. After being analysed with nutritive value, this surimi was combined with Alaska pollock surimi to improve gelling properties. Gel strength, water holding capacity, differential scanning calorimetry and dynamic rheological analyses were carried out to determine the optimum krill surimi ratio. Effects of external additives and their amout on the plural gel system were studied as well. According to the results, the Antarctic krill surimi made in the research possessed a good quality with high percent of crude protein (81.01%), low content of fluorine (79.79 mg/kg) and high content of essential amino acid (521.5 mg/g protein). The best ratio of krill surimi to Alaska pollock surimi was 3:7. The thermal transition temperature of composite surimi gel (45.73, 108.26℃) was significantly higher than that of Antarctic krill (19.24, 97.56℃) (p<0.05). Phenomenan of phase-transition temperature and storage modulus increasing indicated that the mixed gel system had better gelling properties compared with krill surimi. External additives in the mixed krill surimi, with 15% soy protein isolate, 15% egg albumen power, 20% potato starch or 0.4% TGase, could maximize the gel strength, which showed that texture properties of the mixed krill surimi could be increased with food additives.