Frozen storage stability and gel formation of Nile tilapia (Oreochromis niloticus) meat paste and effect of heating time on its gel-forming ability

Abstract

Nile tilapia (Oreochromis niloticus) is one of the most widely cultured fish species in the world. This study investigated surimi production as a sustainability and profitable method for utilization of this species. The objectives were to evaluate the stability of meat paste prepared from washed and unwashed tilapia muscle during stored frozen and to examine the effects of heating time on gel formation and breakdown in the meat paste. We studied the freeze-thaw cycle of mince and surimi prepared from washed and unwashed muscle to understand the stability of frozen storage. The freeze-thaw cycle of mince and surimi were analyzed to assess frozen storage stability including muscle and drip loss measurements. The results showed that freezing surimi at -25°C for five weeks with cryoprotectants (4% sucrose, 4% sorbitol, and 0.2% polyphosphate) enhanced stability. However, the texture and taste of surimi deteriorated over time. Surimi with cryoprotectants showed significantly lower thaw drip loss (p < 0.05) compared to mince without cryoprotectants. Both unwashed and washed minces show the similar result. Further, salt-ground (3% NaCl) paste was incubated in water baths at varying incubation times to evaluate the effects of heating on gel formation and degradation. It was found that gel-forming ability increased with increased heating time at 50ºC, whereas extended heating at 60°C led to degradation of meat paste. These findings demonstrated that cryoprotectants are essential additives for maintaining surimi quality while heating time determines the gelation properties of tilapia meat paste.