Freezing & Defrosting FAQs

A good way to know that it is time to defrost is when you see around 1/2 inch thickness of ice around the inside of the freezer. Another way is to look out for ice crystals forming on frozen food packages and frozen ready meals. Luckily most freezers today are made to be frost-free and require little or no defrosting. However if you have an older model and you want to keep it running efficiently, use these steps to do so. Taking the time to defrost periodically will save you the headache of having a huge mess later down the road.

How to defrost your freezer:

  • Wrap frozen items and frozen ready meals in newspaper and place in a box in a cold area
  • Unplug your freezer and wedge the door open
  • Remove freezer drawers
  • Place towels or any type of absorbent material at the bottom and in front of the freezer to mop up the water as the ice thaws
  • Do not use any sharp implements to remove the ice build-up from the freezer, as this will damage the appliance
  • Once all the ice has thawed, clean the freezer and drawers with warm water
  • Wipe the freezer dry and replace the drawers
  • Plug the freezer back into the mains, making sure that the thermostat is set at the correct level
  • Re-pack the freezer.

Click here for more information on defrosting your freezer.

Refreezing thawed frozen foods is not advised from either a safety or quality point of view. The main reason is to avoid the risk of improper defrosting methods. Freezing foods stops any bacteria found naturally in foods to grow, until the food is defrosted. Once frozen food is thawed, the bacteria become active again. We recommend that thawed foods should be cooked as soon as possible.

However, frozen ingredients can be cooked and then frozen again. Once you have cooked food, you should wait until it has completely cooled to room temperature before placing it in a Tupperware container and then storing it in the freezer. The food will now be stored safely until you decide to warm in up and eat it!

Click here to see more about storing and cooking your frozen food.

A recent poll said that 70% of us buy a frozen turkey at Christmas so here is our guide to defrosting safely.

In the fridge

Defrosting the Christmas frozen turkey in the fridge is the safest way and our recommended method.

Your frozen turkey should be kept in its wrapper in the fridge for the duration and it should be kept on a dish large enough to catch any leaking juices. Thawing your turkey this way might take several days depending on its size (see below for recommended thawing times) but it is the safest way. Your fridge minimises bacteria growth in the meat with its lower temperature. Up to five hours in your fridge per pound of meat should be allowed to thaw your bird. But remember, times vary depending on the temperature of your fridge.

Recommended turkey thawing times

Frozen turkey size Defrost time
8 to 12 pounds 1 to 2 days
13 to 16 pounds 2 to 3 days
17 to 20 pounds 4 to 5 days
21 to 24 pounds 5 to 6 days

Alternatively, follow the instructions provided on the packaging

Microwave Thawing

This method of defrosting is not recommended for turkeys. While waiting for the bird to defrost fully, harmful bacteria will grow quickly in areas where the turkey is already thawed

Note: Additional Safety Recommendations
  • Do not thaw your turkey at room temperature. Harmful food poisoning bacteria may grow
  • Frozen turkey that has been thawed should not be frozen again until after the meat is cooked (cooking reduces the risk of harmful bacterial growth)
  • Frozen pre-stuffed turkeys should not be thawed before cooking (bacteria can multiply in the stuffing whilst defrosting)

Meal Ideas

Check out this superb Sunday dinner made with frozen ingredients.

Depending on the time you have available there are two methods to defrost frozen chicken; in the fridge or in your microwave. Remember – frozen chicken should never be defrosted at room temperature.

Defrosting in your fridge

To defrost your frozen chicken place it at the bottom of the fridge, in a bowl large enough to catch any juices that may drip. Do not allow any of these raw meat juices to come into contact with fridge surfaces or food as this may contaminate them. If the bird has packaging or wrapping this should be kept on during the defrost process. The thawed chicken can be stored in the fridge for a couple of days before you cook it. If your chicken does not have any packaging you should cover the bird whilst it is in the fridge.

This is the slowest method but this is the safest method. You should plan your defrosting time for roughly five hours per pound of meat (see below).

Defrosting times

Chicken size Defrost time
3 lbs 15 hours
5 lbs 24 hours
7 lbs 34 hours
10 lbs 48 hours


Defrosting frozen chicken using your microwave

If you are pressed for time, this method can be useful. Refer to the microwave manual as many microwaves are different and require different times to defrost a whole bird. Care needs to be taken to ensure that you do not dry out the meat when you defrost.

For chicken breasts or small pieces of chicken, ensure that the wrapping is removed before putting the meat in the microwave. Put the pieces in a microwave dish so as to catch dripping juices and, using the defrost setting, defrost two minutes at a time checking progress between each go. Once the chicken pieces have been defrosted, they should be cooked straight away.

Chicken must be properly defrosted before it is cooked. Ensure your chicken is completely defrosted by feeling for ice crystals inside the cavity of the bird. If crystals are there, the bird is not defrosted yet. You can also test thicker parts of the meat with a fork to see if it feels frozen.

Never refreeze chicken once it is defrosted, it is however safe to do so once the meat is cooked. Always clean plates, utensils, surfaces and hands thoroughly, after they have touched raw or thawing meat, to stop bacteria from spreading.

Meal Ideas

Here’s the ideal Sunday dinner made with frozen food ingredients.

Or if you fancy something a little lighter, try one of our other chicken recipes.

Defrosting frozen fish should be carried out overnight in the refrigerator. Do not thaw frozen fish at room temperature as this encourages bacteria growth. Once defrosted, the fish should be eaten within 48 hours.

Defrosting frozen fish is easily done but to get the best results we have some useful tips:

Thawing frozen fish fillets under water is not recommended as the flavour of the fish will be lost. The flavour of fish is salt based and these minerals will be washed away and dissolved in your water.

Defrosting frozen fish in the microwave should be avoided unless you’re in a hurry and the fish has to be cooked immediately. If you use a microwave incorrectly the fish can partially cook and dry out, stop the defrost cycle while the fish is still icy but pliable.

Defrosting Frozen Fish in a fridge

Thawing frozen fish in the fridge is the slowest but safest method

Thawing Time: 6 to 24 hours, depending on quantity. Generally, 6 to 8 hours per pound.

The temperature of the refrigerator should be maintained at 8°C or below as anything between 8°C and 63°C may allow the multiplication of bacteria.

Leave the fish wrapped and place on a plate or a tray to catch the drips as it thaws. Place in the fridge to thaw and keep away from ready-to-eat foods.


Defrosting Frozen Fish in cold water

Thawing frozen fish in cold water is a faster way of defrosting fish

Thawing Time: 1 to 2 hours per pound

This method of defrosting is faster but precautions need to be taken.

  • Fill a basin or bowl with enough cold tap water to cover the frozen fish. Put your fish in a sealed bag and submerge it in the water. The water should be changed every 30 minutes.
  • Do not use warm water, even though it will thaw the fish faster, it may also encourage the growth of bacteria to harmful levels.
  • Once the fish is thawed, it should be cooked immediately.
  • Once the fish is thawed, remove it from the sink and clean all utensils and surfaces affected during the thawing period with hot water and soap.

Defrosting Frozen Fish in a microwave

Thawing frozen fish in a microwave is the quickest method

See your manual for defrosting details

Using a microwave to defrost your frozen fish is a quick method but is not recommended because of the difficulty in getting the different thicknesses of fish fillets to defrost evenly.

Defrosting times vary according to different microwaves and according to the form of fish (whole or pieces) you are thawing. Use the steps below for thawing in the microwave:

  • Place the fish on a microwave rack in a microwave safe pan.
  • Microwave for 1/2 the defrosting time. See time chart below. Then turn the fish pieces over. Place on the rack so the thinnest sections are towards the middle and are overlapping each other.
  • Finish microwaving. Pieces should still be pliable and still cool to the touch. They may be slightly icy but they will finish thawing while they stand for 5 minutes.

Note – If the individual fish pieces are frozen together, defrost in microwave just long enough to be able to separate the pieces and then follow directions above.

Microwave Defrosting Times

Using Defrost Feature or at 50% Power Level

Fish Thickness Frozen-No Ice Glazed
Minutes per lb. Minutes per lb.
Whole-Small   1″ – 1¾” 3½ – 6½   4 – 6½
Fillets   ¼” – 1″  3 – 5  3½ – 5½
Steaks 1″  3 – 5½   3½ – 6

Other thawing tips:

Do not defrost fish at room temperature

  • Always cook defrosted fish that hasn’t been thawed in a refrigerator as soon as possible.
  • Fish thawed in a refrigerator can be kept refrigerated for 2 days.
  • Do not refreeze thawed fish. It is safe to refreeze fish once it has been cooked but some of its quality will be lost

Cooking frozen fish

How you want to cook your fish can determine whether you need to defrost

  • Deep frying in batter – cook from frozen
  • Deep frying in bread crumbs – cook from frozen (although the bread-crumbing is more successful if done with defrosted fish
  • Shallow frying – defrost first. This is mainly a safety issue: the water within the fillets will likely cause the fat / oil to spit or sometimes the fillet can explode in parts
  • Grilling – cook from frozen if thin fillets / steaks (maximum 3cm) or defrost if thick fillets / steaks
  • Baking – cook from frozen if thin fillets / steaks (maximum 3cm) or defrost if thick fillets / steaks
  • Baking in tinfoil – cook from frozen
  • Baking in a crust / pastry – defrost first or the water within will cause soggy pastry
  • Making a stew – cook from frozen if you can safely cut the fillet to size.

Has reading this made you hungry for fish? Try one of our fantastic fish recipes.

Always refer to the on-pack ‘best before’ date. The manufacturer’s ‘best before’ date on frozen foods is a quality indicator and is the date until which the product will remain in peak quality (when stored at -18°C or below).

After the ‘best before’ date a reduction in eating quality may become evident, whilst the product remains safe to eat.

Try to rotate foods; putting newly purchased items at the back of the freezer so older items are used first.

For a handy list of common frozen foods and how long they can be stored visit our pages on storing, defrosting and cooking frozen foods.

The purpose of thawing frozen foods thoroughly before cooking is to ensure that during cooking the food is heated sufficiently to kill harmful bacteria.

There are three safe ways to defrost food:

  • In the refrigerator
  • In cold water
  • In the microwave*

*Most importantly, follow instructions from manufacturer

  • It’s best to plan ahead for slow, safe thawing in the refrigerator. The bottom of the fridge is ideal.
  • For faster defrosting, place food in a leak proof plastic bag and immerse it in cold water. Change water every 30 minutes. After thawing, cook immediately.
  • For defrosting ready meals, always follow the instructions.

Click here to see our guide on how to store, defrost and cook frozen foods.

Most home freezers should operate at temperatures -18°C or lower. Rule of thumb, if your freezer can’t keep ice cream solid, its temperature is above the recommended level.