Farmed Sea Bass and Seabream: A New Opportunity for High Quality Heat-Induced Gel Products

摘要

The effect of farmed fish species (seabream, 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 seabream and sea bass gels were products of high quality, similar to grade AA surimi, reaching a FT of 5 with MTGase addition. The fat content of the gel products attained from sea bass was higher than that of those prepared from seabream (7.6 vs 6.1 %), thus mirroring a higher fat level in the fish itself. MTGase improved textural quality and reduced protein solubility in SDS+DTT. Species had also an important effect on the quality of the heat-induced gels. The gel strength and cohesiveness of seabream gels were higher than those of sea bass gels (mainly for gels containing MTGase), thus indicating a higher textural quality. On the other hand, sea bass gels were harder and presented a higher water holding capacity. Moreover, sea bass proteins were less soluble in SDS+DTT than seabream proteins. Hence, it was proposed that the higher fat level of sea bass may have caused a negative effect on protein during processing, leading to higher aggregation levels and lower textural quality parameters. Nevertheless, these fat gels prepared with unwashed mince from farmed fish species may present a great potential for the aquaculture and fish processing sectors because, besides adequate gelling ability, these gels have a higher nutritional value than commercial gels, especially given their high EPA+DHA omega-3 fatty acids levels. Therefore, new possibilities for increased profitability of these two farmed fish species were evidenced.