Piotr Kulawik1, Dani Dordevic2,3, Florian Gambuś4, Katarzyna Szczurowska4, Marzena Zając1. 1. Department of Animal Product Technology, Faculty of Food Technology, University of Agriculture, Krakow, Poland. 2. Department of Meat Hygiene and Technology, Faculty of Veterinary Hygiene and Technology, University of Veterinary and Pharmacutical Sciences Brno, Czech Republic. 3. Department of Plant Origin Foodstuffs Hygiene and Technology, Faculty of Veterinary Hygiene and technology, University of Veterinary and Pharmacutical Sciences Brno, Czech Republic. 4. Department of Agricultural and Environmental Chemistry, Faculty of Agriculture and Economies, University of Agriculture, Krakow, Poland.
Abstract
BACKGROUND: The present study determined the heavy metal contamination (mercury, cadmium, lead, arsenic and nickel) of nori, restaurant-served sushi and ready-to-eat sushi meals available via retail chains. Moreover, both microbiological load and biogenic amine content in ready-to-eat sushi meals were analysed. RESULTS: All of the nori samples contained high levels of Cd (2.122 mg kg-1 ), Ni (0.715 mg kg-1 ), As (34.56 mg kg-1 ) and Pb (0.659 mg kg-1 ). The studied sushi samples contained high levels of Ni and Pb, reaching 0.194 and 0.142 mg kg-1 wet weight, respectively, being potentially hazardous to women during pregnancy and lactation and small children. None of the studied samples contained high levels of Hg. Overall, 37% of ready-to-eat sushi meals exceeded a microbiological load of 106 cfu g-1 . However, biogenic amine content in all of the samples was low, with a highest histamine content of 2.05 mg kg-1 . CONCLUSION: Sushi is not the source of high levels of biogenic amines even with high microbiological loads. Nevertheless, the high microbiological loads at the end of the shelf-life indicate that some processors might have problems with the distribution chain or implement a poor hygienic regime. Moreover as a result of possible risk associated with heavy metal contamination, the present study highlights the need to establish new regulations regarding the contamination of nori and sushi.
BACKGROUND: The present study determined the heavy metal contamination (mercury, cadmium, lead, arsenic and nickel) of nori, restaurant-served sushi and ready-to-eat sushi meals available via retail chains. Moreover, both microbiological load and biogenic amine content in ready-to-eat sushi meals were analysed. RESULTS: All of the nori samples contained high levels of Cd (2.122 mg kg-1 ), Ni (0.715 mg kg-1 ), As (34.56 mg kg-1 ) and Pb (0.659 mg kg-1 ). The studied sushi samples contained high levels of Ni and Pb, reaching 0.194 and 0.142 mg kg-1 wet weight, respectively, being potentially hazardous to women during pregnancy and lactation and small children. None of the studied samples contained high levels of Hg. Overall, 37% of ready-to-eat sushi meals exceeded a microbiological load of 106 cfu g-1 . However, biogenic amine content in all of the samples was low, with a highest histamine content of 2.05 mg kg-1 . CONCLUSION: Sushi is not the source of high levels of biogenic amines even with high microbiological loads. Nevertheless, the high microbiological loads at the end of the shelf-life indicate that some processors might have problems with the distribution chain or implement a poor hygienic regime. Moreover as a result of possible risk associated with heavy metal contamination, the present study highlights the need to establish new regulations regarding the contamination of nori and sushi.