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was observed. Adenosine monophosphate (AMP) deposition was observed at all
temperatures with a decrease in ATP. Inosine (HxR) increased more rapidly than
other temperatures at −3 °C and hypoxanthine (Hx) increased more slowly than
HxR (Kawashima and Yamanaka 1992). It was reported that Hx is associated with
loss of freshness and flavour, and Hx deposition in the scallop (Nodipecten subnodosus) adductor muscle stored in ice (0 °C) after 12 days reflects the initial stage of
autolytic deterioration as well as bacterial degradation (Pacheco-Aguilar et al.
2008). Increase in Hx of adductor muscle of chilled scallop (Chlamys tehuelchus)
(De Vidode Mattio et al. 2001). Similar increases have been reported for Placopecten
magellanicus (Hiltz and Dyer 1973).
The K value is defined as the ratio (×100) of non-phosphorylated ATP breakdown products to the total ATP breakdown products. Despite that, K value is widely
accepted as a freshness index for many fish species, it is not the same for shellfish
(Ocano-Higuera et al. 2006; Pacheco-Aguilar et al. 2008). However, K value showed
a linear increase in the adductor muscle of Catarina scallop (Argopecten ventricosus) stored in ice (0 °C) and it was stated that K value can be used as good indicator
for monitoring loss of freshness during the shelf life of Catarina scallop (OcanoHiguera et al. 2006). Similarly, a logarithmic increase in K value of adductor muscle
of Pacific lions-paw scallop (Nodipecten subnodosus) during the storage at 0 °C
(ice) (Pacheco-Aguilar et al. 2008).
Formation of octopine from arginine and pyruvic acid is one of the major biochemical processes occurring in postmortem scallop muscle (Venugopal 2006). The
final anaerobic glycolysis products in molluscs are different from vertebrates.
During anaerobic metabolism, octopine accumulates in the muscles of invertebrates
instead of lactic acid. However, it was found that octopine scallop is an inappropriate freshness index (Wongso et al. 1998).
One of the biochemical changes that occur in fisheries after death is the formation of biogenic amines. Biogenic amines are formed by decarboxylation of amino
acids. In a study investigating the biogenic amine contents of scallop (Pecten maximus) stored in ice and at 10 °C, agmatine was found to be the dominant amine and
increased during storage and reached the limit values. Putrescine and cadaverine
increased rapidly after 2 days in ice and 6 days at 10 °C storage respectively (Mackie
et al. 1997). In a similar study, it was reported that agmatine, putrescine and cadaverine increased with the progression of deterioration in scallop adductor muscle
stored at 5 and 15 °C and putrescine and ornithine were good indicators for the
freshness of the scallop adductor muscle (Yamanaka 1989).
3.1.4.3 Post-harvest Handling of Scallops
Transport and Live Storage of Scallops
The main goal regarding live transport must be to deliver live scallops in good condition, every time, and without significant product loss (Overaa 2001). To be able to
mention quality for a food product, freshness is essential, it is essential to be alive
3 Molluscan Shellfish
was observed. Adenosine monophosphate (AMP) deposition was observed at all
temperatures with a decrease in ATP. Inosine (HxR) increased more rapidly than
other temperatures at −3 °C and hypoxanthine (Hx) increased more slowly than
HxR (Kawashima and Yamanaka 1992). It was reported that Hx is associated with
loss of freshness and flavour, and Hx deposition in the scallop (Nodipecten subnodosus) adductor muscle stored in ice (0 °C) after 12 days reflects the initial stage of
autolytic deterioration as well as bacterial degradation (Pacheco-Aguilar et al.
2008). Increase in Hx of adductor muscle of chilled scallop (Chlamys tehuelchus)
(De Vidode Mattio et al. 2001). Similar increases have been reported for Placopecten
magellanicus (Hiltz and Dyer 1973).
The K value is defined as the ratio (×100) of non-phosphorylated ATP breakdown products to the total ATP breakdown products. Despite that, K value is widely
accepted as a freshness index for many fish species, it is not the same for shellfish
(Ocano-Higuera et al. 2006; Pacheco-Aguilar et al. 2008). However, K value showed
a linear increase in the adductor muscle of Catarina scallop (Argopecten ventricosus) stored in ice (0 °C) and it was stated that K value can be used as good indicator
for monitoring loss of freshness during the shelf life of Catarina scallop (OcanoHiguera et al. 2006). Similarly, a logarithmic increase in K value of adductor muscle
of Pacific lions-paw scallop (Nodipecten subnodosus) during the storage at 0 °C
(ice) (Pacheco-Aguilar et al. 2008).
Formation of octopine from arginine and pyruvic acid is one of the major biochemical processes occurring in postmortem scallop muscle (Venugopal 2006). The
final anaerobic glycolysis products in molluscs are different from vertebrates.
During anaerobic metabolism, octopine accumulates in the muscles of invertebrates
instead of lactic acid. However, it was found that octopine scallop is an inappropriate freshness index (Wongso et al. 1998).
One of the biochemical changes that occur in fisheries after death is the formation of biogenic amines. Biogenic amines are formed by decarboxylation of amino
acids. In a study investigating the biogenic amine contents of scallop (Pecten maximus) stored in ice and at 10 °C, agmatine was found to be the dominant amine and
increased during storage and reached the limit values. Putrescine and cadaverine
increased rapidly after 2 days in ice and 6 days at 10 °C storage respectively (Mackie
et al. 1997). In a similar study, it was reported that agmatine, putrescine and cadaverine increased with the progression of deterioration in scallop adductor muscle
stored at 5 and 15 °C and putrescine and ornithine were good indicators for the
freshness of the scallop adductor muscle (Yamanaka 1989).
3.1.4.3 Post-harvest Handling of Scallops
Transport and Live Storage of Scallops
The main goal regarding live transport must be to deliver live scallops in good condition, every time, and without significant product loss (Overaa 2001). To be able to
mention quality for a food product, freshness is essential, it is essential to be alive
3 Molluscan Shellfish