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How to prepare oysters

How to prepare oysters
Image | Matt Slater © Copyright | Cornwall Good Seafood Guide

Recipe by

The Cornish Fishmonger

The Cornish Fishmonger is a family run specialist online fishseller, involved in the fishing industry since its creation by Robert Clifford-Wing some thirty years ago.


The Cornish Fishmonger



Firstly, discard any oysters that are not tightly closed. 

Wash and open oyster just before serving. 

You will need a clean tea towel and an oyster knife (or any sharp knife with a strong, short blade).



Firstly, discard any oysters that are not tightly closed. 

Wash and open oyster just before serving. You will need a clean tea towel and an oyster knife (or any sharp knife with a strong, short blade) to open your oysters.

1. Use a folded towel, hold the oyster with the hinge facing away from your palm.
2. Insert the tip of the blade into the hinge. If you are using a normal kitchen knife, hold the knife by the tip of the blade and NOT by its handle, this will ensure that should the knife slip whilst opening the oyster you will not cut yourself. By moving the blade side to side the hinge will break open.
3. Remove the oyster from its shell, wash in salted water and return it to the shell.



Pacific - Gigas Oysters

Pacific or gigas oysters as they are also known, are cultured or farmed. Being native shellfish of warmer waters, the pacific oyster does not naturally spawn in local waters as the temperature required to start this process is not reached under normal climatic conditions. Breeding is induced by warming tanks of sea water to the required temperature and adding mature oysters. Once the oysters have spawned, the warmed water containing the pelagic spat (immature oyster) holds the microscopic oysters in suspension until sufficient calcification or shell has formed, giving the oyster enough weight to fall and settle out on to catchment mats located on the base of the holding tanks.

Once the oysters are of collectable size (5mm) they are held in suitable containers and regularly graded and re-housed in plaited sacks and placed in deeper water to grow on to marketable size. This process will take around two years, with the eventual weight of saleable oysters being around 80 to 100g.
Water quality and available nutrients are very important in the growth of oysters; being filter-feeding bivalves, the location for oyster beds is critical for healthy growth. The crystal clear waters surrounding Cornwall are well known for their quality and make an ideal habitat for immature oysters.

Native - Helford Oysters

The native or flat oysters are indigenous to local waters and have been harvested for hundreds of years, providing an invaluable source of high quality protein. Cornwall is renowned for its "Helford" oyster fishery that is operated within the river Fal close to Falmouth.

This ancient fishery is unique, in as much as the only motive power used to catch the oyster is "sail or oar". The fishery is tightly controlled by the issue of licences, the months of the year, days of the week and hours of the day that fishing is allowed.  A minimum landing size also protects immature fish, thereby ensuring the fishery for years to come.
Native oysters are in prime condition when there is an "R" in the month; September to April being the months when the oyster is most plentiful.


Native Oyster

Sail and Oar

Truro river and Fal Estuary

Sustainably harvested using lightweight dredges that are towed by traditional sail boats and rowing boats. The unique management of this fishery has resulted in a sustainable harvesting regime that has kept stocks healthy for 150 years.

Pacific oyster



Farmed on the shore in semi rigid plastic mesh cages.

Hand Collection


Hand collection of feral oysters is one method to keep wild populations of this non native species under control. Wild oysters are much more variable in shape and can be very large. They must be depurated before consumption.

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