232
M.L. Cancela et al.
seafood consumption is projected to grow throughout the developing world, while
developed-country consumption remains virtually unchanged (Delgado et al. 2003).
Although provision of seafood from capture fish is declining and partly not sustainable, seafood from aquaculture will potentially overcome this supply issue. It
can deliver a product of defined quality, composition and safety to the market in
all seasons of the year enabling a greater penetration of fish products in the diet of
consumers.
7.5.1 Seafood Quality Has a Multifactorial Background
Quality as a concept must now be considered, as a convergence between consumers’
wishes and needs and the intrinsic and extrinsic quality attributes of food products.
The increasing number of quality attributes which must be considered, increasing globalization and the heterogeneity in consumption habits between countries
are making this convergence progressively more difficult. Fish quality is a broad
and complex concept embracing many components, which have differing relative
importance for producers, processors, retailers, distributors, caterers, consumers,
regulatory authorities and legislators. Recent studies regarding consumers concerns
about seafood clearly point out that strongest interest was displayed for aspects
related to safety guarantee, quality marks and health benefits (Pieniak et al. 2006,
Werbeke et al. 2007). Flesh quality in fish is species-dependent, results from a
complex set of intrinsic traits such as muscle chemical composition (fat content,
fatty acid profile, glycogen stores, oxidative stability, color) and muscle cellularity
(Johnston 1999) and is strongly influenced by a variety of extrinsic factors such as
feeding, pre- and post-slaughter handling, processing and storage procedures. The
trait of flesh quality has proven difficult to improve by traditional selection because
its hereditability is low and the measure for the quality trait is difficult, expensive
and in most cases only possible after slaughter. Furthermore, it is now clear that flesh
quality has a multifactorial background and is controlled by an unknown number
of QTL.
In this section we will try to summarize the information currently available
regarding the application of genomic and proteomic approaches to the improvement
of flesh quality in aquatic species.
7.5.2 Fish Quality Traits Assessed by Genomic
and Proteomic Methods
Selection research in fish has often focused on basic physical traits with high heritability, such as growth rate in salmonids, and this has already made a marked
impact on the aquacultured phenotype. Other traits, especially those linked to quality, have received less attention in selection programs. Quality traits are often highly
complex, being the end results of a number of physiological processes, each of
M.L. Cancela et al.
seafood consumption is projected to grow throughout the developing world, while
developed-country consumption remains virtually unchanged (Delgado et al. 2003).
Although provision of seafood from capture fish is declining and partly not sustainable, seafood from aquaculture will potentially overcome this supply issue. It
can deliver a product of defined quality, composition and safety to the market in
all seasons of the year enabling a greater penetration of fish products in the diet of
consumers.
7.5.1 Seafood Quality Has a Multifactorial Background
Quality as a concept must now be considered, as a convergence between consumers’
wishes and needs and the intrinsic and extrinsic quality attributes of food products.
The increasing number of quality attributes which must be considered, increasing globalization and the heterogeneity in consumption habits between countries
are making this convergence progressively more difficult. Fish quality is a broad
and complex concept embracing many components, which have differing relative
importance for producers, processors, retailers, distributors, caterers, consumers,
regulatory authorities and legislators. Recent studies regarding consumers concerns
about seafood clearly point out that strongest interest was displayed for aspects
related to safety guarantee, quality marks and health benefits (Pieniak et al. 2006,
Werbeke et al. 2007). Flesh quality in fish is species-dependent, results from a
complex set of intrinsic traits such as muscle chemical composition (fat content,
fatty acid profile, glycogen stores, oxidative stability, color) and muscle cellularity
(Johnston 1999) and is strongly influenced by a variety of extrinsic factors such as
feeding, pre- and post-slaughter handling, processing and storage procedures. The
trait of flesh quality has proven difficult to improve by traditional selection because
its hereditability is low and the measure for the quality trait is difficult, expensive
and in most cases only possible after slaughter. Furthermore, it is now clear that flesh
quality has a multifactorial background and is controlled by an unknown number
of QTL.
In this section we will try to summarize the information currently available
regarding the application of genomic and proteomic approaches to the improvement
of flesh quality in aquatic species.
7.5.2 Fish Quality Traits Assessed by Genomic
and Proteomic Methods
Selection research in fish has often focused on basic physical traits with high heritability, such as growth rate in salmonids, and this has already made a marked
impact on the aquacultured phenotype. Other traits, especially those linked to quality, have received less attention in selection programs. Quality traits are often highly
complex, being the end results of a number of physiological processes, each of