We have Clarence Birdseye to thank for discovering how to freeze food successfully. Back in 1924, on a fishing trip to Canada, he found that by leaving fish on the ice it would freeze so quickly that crystals didn't form to spoil its taste and texture.

Freezing, or frosting, as it became known in the 1940s, got into its stride by the '60s, was the economic and time-saving choice for the '70s and '80s, and has found new favour in the '90s and '00s for the nutritional content of certain foods.

Clarence Birdseye's simple theory stands true today, as it's the speed of freezing food that retains its taste and texture - and ensures it's safe to eat. So if you've ever wondered if the fast-freeze really had a purpose for freezing chilled foods, then the answer is yes. When done properly, freezing is the most natural way to preserve foods, as it just turns water inside food into ice crystals.

General Freezing Tips

• Make sure your freezer is set to -18¢ªC. If you are not sure buy a freezer thermometer.
• Get your purchases home as soon as possible.
• Only freeze food when it's cold.
• Food needs to be frozen quickly, so harmful bacteria doesn't grow and ice crystals don't form, so divide food into smaller portions.
• Wrap food individually in rigid containers or strong freezer bags - this ensures there's no cross-contamination or freezer burn which can damage food in the long run.
• Defrost food thoroughly in the fridge. For a quick thaw, submerge in cold water in an airtight package or thaw in the microwave if you will be cooking it immediately. Do not defrost at room temperature, overnight - and never refreeze.
• Label clearly - with waterproof labels.

Vegetables and Fruits
Birds Eye's claim of its peas being in the bag within two to three hours and staying 'as good as fresh' does hold sway. Research by the British Nutrition Foundation shows that 'in some cases frozen foods actually retain more nutrients than unprocessed'. This includes 'frozen vegetables, which are picked and frozen within hours of harvest, whereas fresh vegetables may have been stored for several days before purchase or use'. Frozen vegetables will keep for up to six months in a properly set freezer. If you have a lot of leftover cooked vegetables, fold into mash to make a homity pie and freeze in portions for up to three months in individual portions. Defrost, sprinkle over grated cheese and heat through in a medium-hot oven.

Gluts of Fruit and Vegetables
Make the most of fresh summer flavours by open freezing. Lay out on a large tray and freeze until solid – this will take a couple of hours – then pack into freezer bags, with as little air as possible. Great for all berries (apart from strawberries, which have too high a water content).

Purée or Blanch
If you have a glut of apples, plums or pears, stew them, then mash and cool completely. Freeze in rigid containers in portions, clearly marked, and use with breakfast cereals, crumbles or as sauces. Peas, broccoli, broad beans and cauliflower are great for blanching. Cook for 2 minutes in boiling, salted water. Tip into a sieve and refresh under cold running water. When cold seal into bags in portions. They take no time to cook straight from frozen.

Herbs
Supermarkets sell such big bunches of herbs you'll have plenty left over to freeze. Strip leaves from robust herbs such as thyme, sage and rosemary and seal in freezer bags. For softer herbs such as basil, chives, parsley and coriander, finely chop and drop into ice cube trays with water, then freeze. Drop into soups, stews and casseroles straight from the freezer.

Chicken
For week days, especially in summer, it saves time to have ready roasted chicken breasts in the freezer. Season with salt, thyme and a little olive oil, then cook in a medium hot oven until cooked through; freeze in single portions in foil when cold. Defrost overnight in the fridge. Serve in salads, noodle soups, chopped with vegetables into couscous or in wraps with avocado, lettuce and tomatoes. Also try sliced chicken with chunks of cooked potato, green beans and pesto to coat.

Meat
Generally, uncooked meat freezes for up to six months (and cooked meat freezes for two to three months) in a four-star freezer. Save a portion of cooked meat from Sunday lunch and freeze in slices with a little gravy to keep it moist - this is an easy option with a portion of your frozen vegetables.
When freezing raw meat, the Food Standards Agency (2006) recommends you:

• Always freeze before the 'use by' date. Use within two days of defrosting.
• When meat thaws, liquid oozes out. This liquid will spread bacteria to any food, plates or surfaces that it touches. Keep the meat in a sealed container at the bottom of the fridge, so that it can't touch or drip onto other foods.
• If you defrost raw meat and then cook it thoroughly, you can freeze it again, but remember never reheat foods more than once.
• Always thoroughly clean plates, utensils, surfaces and hands after they have touched raw or thawing meat, to stop bacteria from spreading.

Pulses
It's best to cook pulses from scratch in big batches, cool them as quickly as possible and then freeze in portions for up to two months. These are good for making chillies (kidney beans), stews (chick peas) and salads (cannellini beans).

Milk
According to the Food Standards Agency, you can freeze milk, providing you follow these guidelines:

• Freeze it before the 'use by' date.
• Follow any freezing or thawing instructions on the label.
• Defrost it in the fridge so that it doesn't get too warm – allow about 24 hours for it to thaw.
• When milk is frozen it expands and this can rupture the packaging. Check that the packaging is intact before you defrost it. If it has ruptured it's better not to use the milk.

You can also freeze hard cheese for up to three months (grated is best), and fromage frais for the same amount of time. You can't freeze natural yogurt on its own, but make it into a frozen yogurt dessert and freeze in slices or individual pots.