Temporal variation in muscle fibre area, gaping, texture, colour and collagen in triploid and diploid Atlantic salmon (Salmo salar L)

Abstract

Diploid and triploid Atlantic salmon were reared for 32 months in seawater, from October 1998 to January 2000. During this period of time, four samplings were taken to study differences in quality traits and chemical components in the flesh between diploid and triploid Atlantic salmon. Season was found to be the dominant factor explaining the variation in flesh quality traits in both triploid and diploid fish. Ploidy affected the majority of investigated variables while body size had lesser impact. Triploid Atlantic salmon had fewer small muscle fibres and up to 23% larger mean cross-sectional muscle fibre area than diploids. Triploids also displayed more gaping, softer fillet texture, lower post mortem end pH, darker (L value) and redder (a value) flesh colour, and more soluble and less insoluble collagen compared with diploid fish. No effect of ploidy was found on crude chemical composition. Furthermore, a negative relationship was found between gaping score and muscle fibre area, and a weak positive correlation was found between fibre density and texture firmness. However, when body size and sampling time was included in the statistical model, this relationship between gaping and fibre area became very weak, and the relationship between texture and fibre area was completely negated. This suggests that intra-species variation in both texture and gaping is more related to season and body size than to average muscle fibre area size.

Selection for muscle fat content and triploidy affect flesh quality in pan-size rainbow trout, Oncorhynchus mykiss

“…In the present study, we observed that triploid fish had larger white muscle fibers than diploid fish (+9% and + 15% of the mean diameter for the L line and F line, respectively). Such an effect of triploidy on muscle fibers size was already reported in salmonids (Bjørnevik et al, 2004;Johnston et al, 1999;Poontawee et al, 2007;Sigurgisladottir et al, 2001;Suresh and Sheehan, 1998). In the present study, higher values of lightness were found for both raw and cooked fillets of triploid fish.…”

“…These effects of triploidy on fish biology may lead to consequences in flesh quality, as reported in various salmonid species. Differences between diploid and triploid fish were demonstrated in muscle fiber size, fillet gaping, color, texture and some muscle biochemical characteristics, such as protein solubility (Bjørnevik et al, 2004;Gomez-Guillén et al, 2000;Poontawee et al, 2007;Werner et al, 2008).…”

Texture Measurements in Fish and Fish Products

“…Instruments to measure texture do not have the human ability to evaluate and to interpret multivariate input [39]. If texture can be specified in an early processing step, inferior quality in the final product can be reduced [36,38,40,41]. …”

“…Texture and colour differences were attributed to variation in muscle cell size. Moreover, the relationship among fillet texture, fibre arrangement, and density is not consistent [17,34,40].…”

A comparative study of diploid versus triploid Atlantic salmon (Salmo salar L.). The effects of rearing temperatures (5, 10 and 15 °C) on raw material characteristics and storage quality

“…There has been little investigation of the effects of ploidy on the quality characteristics of (lower L*-value) and more reddish (higher a*-value) compared to that of diploids (Bjørnevik,87 Espe, Beattie, Nortvedt, & Kiessling, 2004 …”