Our food guru Kim Morphew debunks foodie hearsay – from sell-by dates to ageing cheese – so you can waste less and enjoy healthy and safe cooking
1. Myth: food needs to be washed before cooking
Raw chicken: handle with care as it can harbour lots of harmful bacteria that can make you very ill.
Fact: Never wash your chicken! Droplets of water or spray back from a fierce tap are the quickest way to spread any bacteria. If the chicken has juices from the packaging you wish to remove, dab the meat with kitchen paper and dispose of the paper immediately.
Raw meat and fish: The same rule applies as with chicken, as the cooking process is sufficient enough to kill bacteria. Washing simply spreads bacteria around!
Raw vegetables: These can contain the E.coli bacteria, so rinsing under the tap is a good idea. But if the packet already says, ‘washed lettuce’, then there is no need.
Mushrooms: Mushrooms are porous so a quick rinse under the tap will remove the dirt without destroying them. This is far quicker and easier than brushing the mushrooms, which just moves the dirt around!
2. Myth: leftover raw onion can be toxic
As long as the onion has been prepared in a hygienic way and stored in a freezer bag in your fridge – mainly to prevent it stinking eveything out – then it’s fine to use for up to three days.
TIP: Store onions in the fridge so they are less likely to make your eyes water when cutting.
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3. Myth: cheese gets better with age
Not all cheeses age well, and some can even foster harmful bacteria.
Cheese is best enjoyed fresh, although it can be stored in a cool environment for anything from a couple of days to several months, depending on the type, without affecting taste. Bacteria love moist conditions, which is why hard, dry cheese lasts longer.
Cheese low-down:
Parmesan: this has already been matured for anywhere between 18-48 months, depending on the producer. If you leave this in your fridge it will just dry out further and not improve with age, as it was already old in the first place.
Cheddar or hard cheeses: mature cheddar can also dry out if not stored correctly. However, young mild cheddar will mature with age. Wrap the cheese tightly in plastic wrap, and store in an airtight container in the bottom of your fridge.
Brie or other soft cheeses: never eat these cheeses past their use by date. Bin immediately if your soft cheese shows signs of blue or green mould.
4. Myth: food must be eaten within three days of being opened
Many of us limit juice to once a day given the recent health warnings about the amount of natural sugar in it, so there goes your plan for making it last all week. It’s not just juice that carries warnings though. Here’s why:
Fact 1: Once opened, the juice may become exposed to micro-organisms such as bacteria, yeast and mould, which could spoil it. Just as fruit goes rotten, fresh juice can ferment or go sour.
Fact 2: Manufacturers have to cover themselves legally, as once you take the item home they have no control over the storage. This means that they could ‘possibly’ go off and not taste great, so they advise a safe option of three days.
Fact 3: Use common sense – look at it, smell it and taste it.
5. Myth: food can’t be cooked from frozen
Here’s the low down on cooking from frozen and microwave defrosting. It is always recommended to defrost thoroughly before cooking for food safety and quality reasons.
Fact 1: A chicken or joint will take 2-3 times as long to cook from frozen to ensure it is cooked all the way through.
Fact 2: It takes longer for the heat to kill the bacteria, therefore the risk of food poisoning is very high and by the time the meat is cooked it will be dry, overcooked on the outside and often burnt.
Fact 3: Always defrost large pieces of meat or large portions of batch-cooked foods all the way to the centre, with no ice crystals remaining before cooking.
Fact 4: It is fine to defrost in the microwave, even if some random areas may begin to cook. But you must cook the food straight from microwave defrosting to kill the bacteria that are awakening from their deep freeze.
Fact 5: Food such as prawns, mince and really thin burgers can all be cooked from frozen as long as the internal temperature gets hot quickly enough to thaw the centre and kill the bacteria. Whatever you’re cooking needs to be in the 4˚C-60˚C ‘danger zone’ for as little time as possible.
6. Myth: frozen veg are less nutritious than fresh
Wrong! Did you know fresh vegetables could lose up to 45% of their nutrients from being picked to the time they reach your plate? Fresh produce often spends a long time in storage and transportation, and can then sit on supermarket shelves for two weeks before you take them home. On the other hand, frozen veg are picked when they’re fully ripe and at their peak nutritionally, and are usually frozen within hours of harvest, making them a good choice.
7. Myth: food can’t be eaten after use-by, best before and sell by dates
Use by: you’ll see these dates on foods that go off quickly, such as ready prepared salads, meat and smoked fish. Don’t use food or drink after the ‘use by date’, even if it looks and smells fine – you could put your health at risk.
Best before: these dates appear on a lot of frozen, tinned and dried foods and refer to quality. It doesn’t mean the food will be harmful past its date, but rather its quality may not be at its best, or it could lose flavour or texture.
Sell by: this is the instruction for the shop staff to help with stock control.