Shellfish safety

Shellfish include seafood such as prawns, and live molluscs such as mussels, oysters, cockles, whelks, scallops and clams. Risks to food safety include chemicals, toxins, viruses and pathogenic bacteria.

Shellfish toxins (Paralytic, Diarrhetic and Amnesic ) are produced by naturally occurring marine phytoplankton, and detected levels are higher in summer months. Diarrhetic shellfish poisoning can result in nausea, vomiting, diarrhoea, and abdominal pain accompanied by chills, headache, and fever. Symptoms generally present themselves between 30 minutes and two or three hours after eating affected shellfish, and can last for two or three days. (Food Standards Agency)

The main controls relate to the use of reputable approved suppliers who have obtained live molluscs from approved harvesting areas, correct storage, preparation, removal of dead molluscs, rinsing and correct cooking (except oysters which are generally eat raw).

Buying Shellfish

• Ensure that your supplier or source is reputable (and if possible) the shellfish is sustainable.

• When the shellfish is delivered, make sure that it is refrigerated or kept on ice. Store the shellfish in a fridge as soon as possible.

• Check the freshness of the shellfish by looking at the harvest health certificate. It should be no more than 2 days since the shellfish was harvested.

Storing Shellfish

• Store your shellfish in a refrigerator as soon as it has been delivered: refrigerate at < 5°C or if frozen <-18°C. It is critical that a use by date/best before date is made visible on the product. Fresh shellfish should be consumed with 5 days of its harvest.

• Fridge/freezer temperatures should be checked and recorded twice a day.

• Live shellfish cannot be stored in an airtight container it must be able to ‘breathe’.

• If the shellfish is to be cooked store in a non-ready to eat storage area in a high-sided container.

Preparing Shellfish

• When preparing live bivalve shellfish such as mussels, make sure that the outer shell closes when you tap it – discard any that don’t

• Before cooking do a visual check of each (discard any with broken shells) and consider the smell of the shellfish – it should be fresh and salty.

• Shellfish must be cleaned in running water (not left in a sink of water) prior to cooking.

• Don’t allow raw shellfish or its fluid to come into contact with ready-to-eat food. Also use separate utensils and boards for raw and ready to eat shellfish.

• Consider customers with allergies.

• Cook the shellfish to 70^oC for 2 minutes to kill the pathogenic bacteria – note this will not kill viruses or inactivate any toxins present, hence the controls already mentioned are critical to ensure the safety of the shellfish

It is a legal requirement for businesses to put in place appropriate controls to ensure the safety and hygiene of all food consumed. Therefore, it is worth implementing a secure HACCP plan for shellfish safety in your business.

If you have any queries or would like more information, please do not hesitate to contact us.