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method for some shellfish products, some species have been reported to remain
toxic for a long time (Shumway et al. 1995).
Although toxins cannot be destroyed by normal cooking procedures, it is reported
that coagulation of proteins in shellfish tissues may cause redistribution in the
organs of shellfish and some toxins can be released into cooking liquids (FAO
2016). It is reported that even if cooking does not eliminate the danger of poisoning,
in case of low toxicity can reduce toxicity to safe levels. Some researchers have
determined that heat treatment and cooking are effective in reducing PSP toxicity.
These effects were probably caused by the release of toxin into cooking water.
MacDonald (1970) reported the effectiveness of pan-frying cooking in shellfish
products in reducing PSP toxicity. Noguchi et al. (1980a, b) identified a sharp
decrease in toxin levels after sterilization of infected scallops. Prakash et al. (1971)
found that cooking caused a 70% reduction in the toxicity of soft-shell clam.
Berenguer et al. (1993) also concluded that the industrial canning process caused a
decrease in the PSP levels of the Mediterranean cockles. The standard canning process provided a reduction (over 50% of toxicity level in raw material) in PSP toxicity of mussel meat (Vieites et al. 1999). A significant reduction (approximately
65%) in toxicity of lobster hepatopancreas was observed after boiling or steaming
(Lawrence et al. 1994).
Reboreda et al. (2010) determined that thermal treatment on PSP contaminated
mussels, oysters and oysters reduces PSP levels below the detection limit.
5.3.2 Diarrhetic Shellfish Poisoning (DSP)
Diarrhetic Shellfish Poisoning is caused by toxins (ocadaic acid, dinofisis toxin,
yessotoxin pectotoxin) produced by dinoflagellates (Aune and Yndstad 1993).
Diarrhetic shellfish toxins (DST) are a group of phycotoxins that include Okadaic
acid (OA) and structurally related toxins. DSP is caused primarily by okadaic acid
(OA) and its derivatives, the dinophysistoxins (DTXs), produced by dinoflagellate
species of Dinophysis and Prorocentrum (Gosling 2015). The first group, acidic
toxins, includes okadaic acid (OA) and its derivatives named dynophysistoxins
(DTXs). The second group, neutral toxins, consists of polyether-lactones of the pectenotoxin group (PTXs). The third group includes a sulphated polyether and its
derivatives the yessotoxins (YTXs) (FAO 2004).
It has been reported that the shellfish causing DSP in Japan are mussels (Mytilus
edulis and M. coruscum) scallops (Patinopecten yessoensis and Chlamys nipponesis
akazara) and short-necked clams (Tapes japonica and Gomphina melaegis) and in
the European Atlantic coast are Mytilus edulis and Ostrea sp. (FAO 2004). Although
DSP is predominantly seen in Europe and Japan, it is reported to be seen in North
and South America, Australia, Indonesia, and New Zealand due to the spread of
toxic dinoflagellates globally (Scoging and Bahl 1998).
The main symptoms of DSP are cramps, severe diarrhoea and vomiting and
patients usually recover within 3–4 days (Gosling 2015). Consumption of shellfish
5 Shellfish Safety
method for some shellfish products, some species have been reported to remain
toxic for a long time (Shumway et al. 1995).
Although toxins cannot be destroyed by normal cooking procedures, it is reported
that coagulation of proteins in shellfish tissues may cause redistribution in the
organs of shellfish and some toxins can be released into cooking liquids (FAO
2016). It is reported that even if cooking does not eliminate the danger of poisoning,
in case of low toxicity can reduce toxicity to safe levels. Some researchers have
determined that heat treatment and cooking are effective in reducing PSP toxicity.
These effects were probably caused by the release of toxin into cooking water.
MacDonald (1970) reported the effectiveness of pan-frying cooking in shellfish
products in reducing PSP toxicity. Noguchi et al. (1980a, b) identified a sharp
decrease in toxin levels after sterilization of infected scallops. Prakash et al. (1971)
found that cooking caused a 70% reduction in the toxicity of soft-shell clam.
Berenguer et al. (1993) also concluded that the industrial canning process caused a
decrease in the PSP levels of the Mediterranean cockles. The standard canning process provided a reduction (over 50% of toxicity level in raw material) in PSP toxicity of mussel meat (Vieites et al. 1999). A significant reduction (approximately
65%) in toxicity of lobster hepatopancreas was observed after boiling or steaming
(Lawrence et al. 1994).
Reboreda et al. (2010) determined that thermal treatment on PSP contaminated
mussels, oysters and oysters reduces PSP levels below the detection limit.
5.3.2 Diarrhetic Shellfish Poisoning (DSP)
Diarrhetic Shellfish Poisoning is caused by toxins (ocadaic acid, dinofisis toxin,
yessotoxin pectotoxin) produced by dinoflagellates (Aune and Yndstad 1993).
Diarrhetic shellfish toxins (DST) are a group of phycotoxins that include Okadaic
acid (OA) and structurally related toxins. DSP is caused primarily by okadaic acid
(OA) and its derivatives, the dinophysistoxins (DTXs), produced by dinoflagellate
species of Dinophysis and Prorocentrum (Gosling 2015). The first group, acidic
toxins, includes okadaic acid (OA) and its derivatives named dynophysistoxins
(DTXs). The second group, neutral toxins, consists of polyether-lactones of the pectenotoxin group (PTXs). The third group includes a sulphated polyether and its
derivatives the yessotoxins (YTXs) (FAO 2004).
It has been reported that the shellfish causing DSP in Japan are mussels (Mytilus
edulis and M. coruscum) scallops (Patinopecten yessoensis and Chlamys nipponesis
akazara) and short-necked clams (Tapes japonica and Gomphina melaegis) and in
the European Atlantic coast are Mytilus edulis and Ostrea sp. (FAO 2004). Although
DSP is predominantly seen in Europe and Japan, it is reported to be seen in North
and South America, Australia, Indonesia, and New Zealand due to the spread of
toxic dinoflagellates globally (Scoging and Bahl 1998).
The main symptoms of DSP are cramps, severe diarrhoea and vomiting and
patients usually recover within 3–4 days (Gosling 2015). Consumption of shellfish
5 Shellfish Safety