Access to market
To produce a high quality, safer live bivalve in compliance with legal obligations producers must adhere to European Hygiene Regulations. These Regulations came into force in January 2006 and apply to the placing of live bivalve shellfish on the market for human consumption.
Bivalve molluscs filter phytoplankton (natural microscopic plant cells) from the water to grow. They also filter bacteria, some of which can be a risk to human health. However, there is rigorous EU legislation to protect those who consume molluscan shellfish by: ensuring that shellfish sold into the supply chain meet strict food safety (health and hygiene) standards; and by classifying harvesting areas and beds from which shellfish are gathered.
Classification of shellfish harvesting areas
Live bivalve mollusc harvesting grounds must be classified by the Food Standards Agency. This classification is based on the presence of E.coli in the mollusc flesh.
Class A grounds - Mollusc flesh has less than 230 cfu's of E.coli per 100g of flesh. This allows molluscs to be sent straight to market without any intervention.
Class B grounds - Mollusc flesh has between 230 and 4,600 cfu's per 100g of flesh. This means molluscs must be relayed to cleaner waters, purified through an approved dapuration unit or heat treated before they can be sold for human consumption.
Class C grounds - Mollusc flesh has between 4,600 and 46,000 cfu's per 100g of flesh. This means molluscs must be relayed to designated cleaner waters for a minimum of two months, or they are purified or heat treated to meet Class A of Class B standards.
Prohibited area molluscs cannot be harvested for human consumption.
Dispatch centres and purification units
To protect human health, all molluscan shellfish must meet an end product standard of less than 230 before they can be placed on to the market. Most of the UK harvesting areas are Class B which means that UK producers have to purify (i.e. hold in depuration units) their bivalve molluscs before selling them into the food supply chain.
For further information
Good manufacturing practice guidelines -
Live bivalves workbook
Seafish Guidance note - Classification of shellfish harvesting areas
Seafish Guidance note - Reuse of seawater for purification systems
Seafish Guidance note - Co-funding SARF projects
Seafish has prepared guides and forms for correct HACCP (Hazard Analysis and Critical Control Point) procedures for bivalve molluscs.
Risk assessment for bivalves - a brief introduction
An Introduction to HACCP for Bivalve Mollusc Purification and Dispatch Centres
Delivering safer seafood
A good understanding of biotoxin controls and how the animals respond to various handling regimes can lead to safer seafood being delivered to market.