Effect of ozonation and γ-irradiation on post-harvest decontamination of mussels (Mytillus galloprovincialis) containing diarrhetic shellfish toxins

Artemis Louppis , Panagiota Katikou , Dimitrios Georgantelis , Anastasia Badeka (1) , Michael Kontominas

1 Department of Chemistry [Ioannina]

Contamination of shellfish with diarrhetic shellfish poisoning (DSP) toxins readily occurs during algal blooms. Such phenomena raise important public health concerns and thus comprise a constant challenge to shellfish farmers, the seafood industry and health services, considering the increasing occurrence of toxic episodes around the world. To avoid the detrimental effects of such episodes, research has focused on the use of various detoxification methodologies which should be rapid, efficient, easy to apply, and will not alter quality and sensory properties of shellfish. In the present study, both ozonation (15 mg kg^-1 for 6 h) and γ-irradiation (6 kGy) have been utilized in order to reduce toxin content of contaminated shucked mussels, collected during the DSP episodes of 2007 and 2009 in Greece. DSP toxicity was detected using the mouse bioassay (MBA) while determination of toxin content of the okadaic acid (OA) group (both free and esterified forms) was conducted by LC/MS/MS analysis. Toxin reduction using γ-irradiation was in the range of 12-36%, 8-53% and 10-41% for free OA, OA esters and total OA respectively. Appearance and texture of irradiated mussels deteriorated, pointing to a low potential for commercial use of this method. Ozonation of mussels resulted in toxin reduction in the range of 6-100%, 25-83% and 21-66% for free OA, OA esters and total OA, respectively. Reduction of OA content was substantially higher in homogenized mussel tissue, compared to that of whole shucked mussels. In addition, differences detected with regard to quality parameters (TBA, sensory attributes) between ozonated and control mussels were not considerable. Eventhough varying % reductions in OA and its derivatives were achieved using ozonation under specific experimental conditions tested, it is postulated that upon optimization, ozonation may have the potential for post-harvest commercial DSP detoxification of shucked mussels.

Mots clés: Life Sciences

Artemis Louppis, Panagiota Katikou, Dimitrios Georgantelis, Anastasia Badeka, Michael Kontominas. Effect of ozonation and γ-irradiation on post-harvest decontamination of mussels (Mytillus galloprovincialis) containing diarrhetic shellfish toxins. Food Additives and Contaminants, 2011, ⟨10.1080/19440049.2011.603365⟩. ⟨hal-00740353⟩