Bivalve Purification Operations

Seafish and the Royal Environmental Health Institute for Scotland (REHIS) have joined forces to create a new training programme in Bivalve Purification Operations.

This course develops knowledge of bivalve biology, equipment design and operation and other key issues. The course is designed to cover the technical aspects of operating a purification centre and is suitable for all staff members from operatives to managers.

This is the first time this kind of training has been brought together into a formally recognised course accredited by a major UK food safety awarding body.

This theory-based course can be delivered on site or offsite. Suitable for all staff from Managers to Operatives.

The course lasts around five hours or more and covers the following sections:

  • Threats to Human Health;
  • Legislation;
  • Biological Requirements of Bivalves;
  • Risk Assessment Management;
  • Purification Tank Design and Operation;
  • Shellfish Handling;

There is a short test at the end of the course. participants are awarded a Seafish/REHIS joint award certificate or a Seafish attendance certificate as appropriate.

More Information?

Contact the Scottish or Southern Shellfish Training Centres

View a typical course promotion leaflet

View the course syllabus

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Course Details

This programme aims to provide an introduction to how appropriate bivalve handling can ensure consumer protection by way of the effective purification* of bivalves prior to despatch. The programme will introduce the concepts and terms that apply to bivalve purification operations and will promote the application of this knowledge in the seafood industry.

*(Purification and depuration are in this context interchangeable)

Training courses based around this programme will provide the initial learning input for persons new to purification and should form the basis for further formal and informal learning and development.

A practical approach to training is recommended and individuals should be actively encouraged to participate fully. Examples used during the delivery of training should reflect current best practice within the industry.

All objectives to be prefixed by the words: The expected outcome is that, in the context of bivalve purification, the course participant is able to:

1. Overview

1.1. Describe briefly what is meant by bivalve purification operations;
1.2. State the health and safety requirements associated with the purification process;
1.3. List the threats to human health posed by consuming bivalves;
1.4. State the food safety requirements associated with the purification process;
1.5. List the types of purification systems;
1.6. State their responsibilities under food safety legislation;
1.7. Identify the legal requirements controlling the depuration process;
1.8. List the classifications given to shellfish growing areas and describe how these impact on the depuration process;

2. The principles of shellfish handling and storage

2.1. Explain how to prepare shellfish for adding to the purification system;
2.2. Explain why it is important to remove dead or damaged shellfish before depuration begins;
2.3. Describe how to handle bivalves as live animals and the problems associated with improper handling;
2.4. Describe how shellfish become stressed and why it is important to minimise the stress caused to shellfish;

3. The principles of bivalve purification operations

3.1. Describe how to prepare a purification system for receiving shellfish;
3.2. Explain why shellfish are washed before and after depuration;
3.3. List the environmental conditions required for effective depuration and the parameters for:

  • Water flow;
  • Salinity;
  • Temperature;
  • Oxygenation;
  • Sterilisation;
  • Duration;
  • Biomass density;
  • Species specific needs;

3.4. List the requirements for loading the system and the density of bivalves in the system;
3.5. Describe the signs which indicate that shellfish are purging;
3.6. Describe the role of disinfection and how this is achieved in purification systems;
3.7. Describe the risks presented by harmful algal blooms;

4. Food safety and bivalve purification

4.1. Describe HACCP and list the identified critical control points controlling the depuration process;
4.2. List the identified critical control points associated with the storage and dispatch of shellfish;
4.3. List the risks of cross contamination and re-contamination following depuration;
4.4. List the key legal requirements controlling the dispatch of Shellfish;