Back to basics: how to freeze

I thought it would be good to get back to basics, the ground rules so to speak.  So this week we'll cover everything there is to know about how to freeze.

The basic rule of thumb with freezing food is

freeze quickly and defrost slowly

This gives your food the best chance of being unaffected by the freezing process.  It has something to do with the ice crystals that form in the food but I don't want to get technical here.  I just want your food to taste great, I want your food to taste like it had never stepped foot in the freezer.

So here are my top tips for freezing food (brace yourself, it's quite a list):

  • Make sure your freezer is working well and operating at -18°C (0°F) or below.  You can check the temperature with a freezer thermometer, available from good kitchenware shops. 
  • If you're not sure how long to store food in the freezer: check the inside of the freezer door. There's normally a table or diagram that shows how long you can freeze different kinds of food.  Or check out this link.
  • When cooking, make sure your food cools to room-temperature or refrigerator-temperature before placing it in the freezer.  If you place hot food in the freezer you may cause the surrounding food to defrost (and icecream to melt) and you will slow down the performance of your freezer.
  • Try not to freeze enormous quantities of food at one time, the recommended amount to freeze is 1kg of food for every 25 litres of freezer capacity.  
  • If you have a large freezer it's a good idea to allow plenty of air to circulate around the food to help it freeze quickly.  Once frozen you can pack the food tightly.
  • I will write a separate post about how to store foods (in ceramic dishes, in aluminium trays etc) but the main thing to remember is to store your food as thinly as possible so they can freeze quickly and defrost easily.  For example, pack hamburger patties in a single layer rather than in a large bundle, or store your casseroles and curries in zip-lock bags so they will form flat “pillows” of food, rather than in large, boxy containers.
Source.  Check out those soups!
This photo is a tad unrealistic, but you get the idea
  • Make sure you freeze your food in usable portions.  It is impossible to cut a single portion of soup or casserole from a frozen hunk.  Invest some time up front and create portions that suit you and your household: 1-person size, 2-person size, kid-size, family-size etc.  You'll be glad you did!

  • Dehydration is the enemy of frozen food.  Always store food in air-tight containers or cover well with cling wrap before freezing.  Some websites/books recommend using double layers of cling wrap, but I normally use one layer and it's fine. If I wrap food in aluminium foil I often re-wrap it in cling wrap as the foil isn't airtight.  Any food that is exposed to the cold air in the freezer will eventually become dry on the surface (often called “freezer burn”) and may even taste different.  
  • In my books I refer to "flash freezing".   I recommend this for cookie dough in particular because if you place the balls of dough in a bag or container they will stick together in one large clump when they are frozen.  To flash freeze: line a tray with non-stick paper, place food on the tray so that they're not touching, then freeze.  Once frozen, transfer the food to a zip-lock bag or plastic container and return to the freezer.

  • There are some foods that don’t freeze well so you won't find them in my recipes:  strawberries, salad ingredients (lettuce, carrot, cucumber, tomato etc), boiled eggs, strawberries, mayonnaise, gelatin, custard etc.  Here's a handy A-Z list of what freezes well and what to avoid.
  • Bear in mind that foods that contain salt and fats can become rancid more quickly.  Any recipe containing bacon or ham should be eaten sooner rather than later.
  • Strong flavours such as garlic or chilli can intensify after storage in the freezer.  Keep this in mind when adding chilli to spicy recipes!
  • Full-fat cheeses freeze better than low-fat cheeses.  This is good to know if you like to freeze sandwiches that contain cheese, or if you put cheese in the freezer before it goes off.
  • Many people ask me if it's OK to re-freeze meat.  The answer is yes and no: If you have frozen  raw meat you can defrost the meat and cook it in a recipe then refreeze it, as long as you cook the meat completely.  Eg, you may have minced (ground) beef in the freezer.  You can defrost it, prepare bolognaise using the beef, then you can freeze the cooked bolognaise.  Do not defrost raw meat, prepare it without cooking (eg placing it in a marinade) then refreeze it.
  • When preparing a seafood recipe for the freezer, make make sure you buy fresh seafood.  Most fishmongers will display a sign saying "defrosted for your convenience" or something similar so you'll know that it has already been frozen. Just ask your fishmonger if you're not sure.
  • Cakes freeze well, but there's a few things to know about icing and decorating cakes for the freezer. Check out this blog post I wrote about cakes.  And while we're on the subject of baked goods: here are my handy hints for freezing quiches.
  • If you have food that has been lurking in the freezer for a REALLY long time, don't automatically think you need to throw it out.  According to Food Science Australia (a joint venture between the Victorian government and CSIRO) “frozen foods do not become unsafe to eat even when held for years at -18°C. The changes affect the sensory and nutritional properties of the food rather than its safety.”   This is great news!  Your frozen foods are safe to eat but they might suffer a little in other ways (colour, texture, nutrition etc).  

In the next few weeks I'll cover how to store food for the freezer, and how to defrost. Riviting stuff ... not.  But it's good to get these things squared away so you know the fundamentals.

If you have any questions or comments feel free to drop me a line.

Eat well.  Be well.
Susan x