Decrease of marine toxin content in bivalves by industrial processes.
Harmful algal blooms cause important economical losses due to the accumulation of toxins in shellfish. Natural detoxification occurs but this mechanism is very slow in most cases. The achievement of a method for the rapid detoxification of commercial bivalves would be very interesting for the shellfish harvesting sector in order to diminish economical losses due to harvesting areas closure. In this work, four different methods easily applicable in the food industry (freezing, evisceration, ozonization and thermal processing) were studied to gain the detoxification of four species of bivalves (mussels, scallops, clams and cockles) contaminated with the three main types of toxins (ASP, DSP, PSP). Results show that for ASP a significant decrease of the toxin levels below the legal limit (20 microg/g) is achieved by using hepatopancreas ablation or combination of simple steps (evisceration and/or thermal processing/and or freezing). In our hands, PSP toxin levels are sharply decreased under the limit of detection (35 microg STX eq/100g) after a thermal processing, inducing percentages of detoxification higher than 50%. The effect of freezing on the levels of PSP is very dependent on the matrix studied. DSP toxins are not significantly reduced with none of these methods.
Reboreda
Antonio
A
Microbiology and Toxins Area, ANFACO-CECOPESCA, Campus Univ. 16, 36310 Vigo PO, Spain.
Lago
Jorge
J
Chapela
María-José
MJ
Vieites
Juan M
JM
Botana
Luis M
LM
Alfonso
Amparo
A
Cabado
Ana G
AG
D000818:Animals; D001681:Biological Assay; D049872:Bivalvia / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D004064:Digestive System / Q000737:chemistry; D005511:Food Handling / Q000379:methods*; D019649:Food Industry; D005615:Freezing; D043143:Hepatopancreas / Q000737:chemistry; D006358:Hot Temperature; D006868:Hydrolysis; D007202:Indicators and Reagents; D007608:Kainic Acid / Q000031:analogs & derivatives / Q000737:chemistry; D008387:Marine Toxins / Q000032:analysis*; D019319:Okadaic Acid / Q000031:analogs & derivatives / Q000737:chemistry; D010126:Ozone / Q000737:chemistry; D012015:Reference Standards; D012530:Saxitoxin / Q000737:chemistry; D017747:Seafood / Q000009:adverse effects* / Q000032:analysis*
D007202:Indicators and Reagents; D008387:Marine Toxins; D019319:Okadaic Acid; D012530:Saxitoxin; D010126:Ozone; C012301:domoic acid; D007608:Kainic Acid