Going crabbing is a lot of fun, and sometimes we return home with many more crabs than we can use immediately. If you are in this position, you need to find a way to keep your crabs alive until you can cook them (never cook a dead crab). You may be eyeing your fridge, but now you want to know: how long will blue crabs live in the refrigerator?
Blue crabs typically live only for 6 to 8 hours in an unmodified fridge. However, if you modify your fridge with a temperature controller, open the door from time to time to replenish the oxygen, and keep it humid, the crabs will live for more than 48 hours.
Although you can keep blue crabs alive for a short while in the refrigerator, several factors in the design of fridges make them undesirable for use for this purpose. However, you can modify a refrigerator to create a custom cool room for storing your blue crabs, and we will look at how to do this.
How Long Blue Crabs Can Live In The Fridge
Although some people have had success keeping blue crabs alive for up to 48 hours inside stock refrigerators with the temperature on its maximum setting (warmest), most often, people have reported that crabs die after only 6 to 8 hours or so in an unmodified fridge.
However, it is possible to modify a fridge to keep crabs in. Under such circumstances, they will keep for more than 48 hours, but people typically use them sooner because they get hungry after about 48 hours despite being chilled and dormant. They will start eating each other, which is undesirable or starve.
If your crabs starve or die for any other reason, enzymes in the mid-gut gland attack the gland’s tissue, destroying the barrier between the gut and the meat. The enzymes then spread into the flesh and digest it, making it mushy and bacterial numbers grow explosively. The flesh tastes unpleasantly of ammonia and rapidly becomes toxic to eat, causing a nasty type of food poisoning.
How To Store Blue Crabs In A Refrigerator
Most refrigerators are designed to keep things in the range of between 30 and 45 degrees Fahrenheit. This range is generally too cold for crabs and will kill them (although the upper end of the range of some fridges will work okay).
Get a cheap infrared thermometer to monitor temperatures in your refrigerator.
Keep your crabs covered in a towel, newspaper, or burlap, and keep this layer moist to prevent the crabs from drying out. Keep the humidity in the highest possible setting to raise moisture levels inside the fridge.
To ensure that the crabs get enough oxygen, open the door occasionally to replenish the air inside the fridge.
If you can, try to get hold of a commercial refrigerator, as these will hold a lot more bushel baskets of crabs than a household fridge and allow you to set the temperature to the correct range (48 to 58 degrees Fahrenheit).
How To Modify A Fridge For Keeping Blue Crabs Alive
You can modify a fridge to stay warmer using a temperature controller commonly used by people making their own beer. Search for a reliable brand of temperature controller and hook it up to the fridge you want to use as per the instructions. Set the temperature on the controller; you will have a refrigerator in the magic range.
The 3 Factors In Keeping Blue Crabs Alive In The Fridge
Blue crabs will survive for a certain length after you’ve caught them, with 3 major factors affecting how long they survive: temperature, oxygen, and humidity.
The Ideal Temperature Range To Store Blue Crabs
Blue crabs stay alive best when temperatures are between 48 and 58 degrees Fahrenheit. Although this is a range of 10 degrees, we recommend you avoid large temperature swings, as these stress the crabs and cause them to die. You also do not want to chill your crabs too rapidly, which stresses them. Gradually lower the temperature you keep them at.
When transporting crabs home in a cooler or bushel basket, keep it inside your vehicle with the air con running to keep the temperature cool and stable. If you must have the container in the back of a truck, keep it behind the cab to reduce wind turbulence that has a drying effect. If summer temperatures are high, in the 70s, get your crabs home quickly.
Maintaining Oxygen And Humidity When Storing Blue Crabs
Blue crabs naturally live in water and breathe oxygen dissolved in the water using their gills. However, they can also breathe air. When taken from the water, they dispel the water from their gills (which causes the foaming you see). Doing so allows them to take up oxygen from the air.
Once they have started breathing air, submerging them again will stress them and cause them to die quicker. If transporting the crabs by cooler, do not allow standing water to accumulate and cover them.
They will not be submerged in water if you store them in the refrigerator. However, oxygen levels will gradually decrease as the crabs use it. Once the oxygen has depleted, the crabs will die. As dead crabs are unsuitable for cooking, this limits how long you can keep them in the fridge.
The fridge’s fans also tend to have a slight drying effect on the crabs, which reduces the humidity around their gills. As they require moist gills to breathe, they gradually asphyxiate in the fridge.
Assess Whether Blue Crabs Are Still Alive Before Cooking
Assess whether your crabs are alive before cooking them – you should only cook live crabs to avoid food poisoning. If your crabs are visibly moving and annoyed, that’s a good sign. If not, put them on the ground and see whether they move. If a crab doesn’t move on the ground, that doesn’t necessarily mean it’s dead. There are two more tests you can perform to see whether it’s alive.
Try pulling down on the crab’s mouth. If it tries to close its mouth, you can cook it. If it doesn’t, hold it with the underside facing you and gently pull down on a leg so that it just detaches. If it bounces back into place when you release it, the crab is safe to cook. If the leg hangs loosely, discard the crab.
Conclusion
If you have a glut of blue crabs, you can keep them alive for a few hours in the refrigerator. If you have an old fridge you can modify, you can keep your crabs alive for longer and enjoy them when you are ready. But ensure that you discard any dead crabs before cooking.
