Quality differences between heat-induced gels from farmed gilthead sea bream (Sparus aurata) and sea bass (Dicentrarchus labrax)

Abstract

The effect of farmed fish species (sea bream, Sparus aurata, versus sea bass, Dicentrarchus labrax) on the quality of heat-induced gel products was evaluated. Additionally, the effect of microbial transglutaminase (MTGase) incorporation (0.5%, w/w) into the gels on their quality was also assessed.Both sea bream and sea bass yielded gel products of high quality. The fat content of the gel products attained from sea bass was higher than that of those prepared from sea bream (7.6% vs. 6.1%). Therefore, fat gels prepared with unwashed mince from farmed fish species may present a great potential for the aquaculture sector because, besides adequate gelling ability, these gels have a higher nutritional value than commercial gels, especially given their high eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) levels. Moreover, MTGase improved textural quality and reduced protein solubility. The gel strength, cohesiveness, and rupture properties of sea bream gels were higher than those of sea bass gels (mainly for gels containing MTGase), thus indicating a higher textural quality. Sea bass proteins were less soluble than sea bream proteins. Different hypothesis were put forward concerning the protein phenomena underlying such differences between the two farmed fish species.