Did you know the use-by date on food isn't valid once you've opened the packet?
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Packaged foods with a shelf life of less than 2 years must have a label showing the use-by or best-before date.
Use-by dates are about food safety. The date’s determined by the time required for the pathogens in food to grow to levels above which illness might occur. As long as the food is stored correctly and isn't opened, it should be safe to eat before its use-by date. After the use-by date, a food can't legally be sold and shouldn't be eaten.
Use-by dates usually appear on perishable food like meat, poultry and deli products.
Best-before dates are about food quality. Food can be sold and eaten after its best-before date as long as it’s been stored according to the instructions on the label. But it may have lost quality and some nutritional value.
You'll find best-before dates on less perishable foods such as cereals, flour and canned goods.
As soon as you open any packaging, the shelf life becomes the same as if the product was unpackaged.
For example, a packet of vacuum-packed smoked salmon may have a use-by date that’s 1 month away – but once you’ve opened it, you should keep it in the fridge and eat it within 2 days.
Another important factor in food safety is how it's stored in your fridge. Here are the basic rules:
How long it is safe to keep a particular food depends on many factors: its water and protein content, its freshness and quality when you bought it, the temperature at which it has been stored, the type of pathogens likely to grow on the food, and your immune status.
Also, use-by dates should be treated with caution if you are pregnant or have lowered immunity due to illness or medical treatment.
Always take note of the use-by date and storage instructions if there are any. As a general guide, our table shows how long you can keep food in your fridge once the packaging is opened.
|Product||How long it lasts|
|Camembert or brie||1 week|
|Canned baked beans||3 days|
|Canned fish||2 days|
|Canned whole peeled tomatoes||3 days|
|Cooked chicken||2 days|
|Cottage cheese||5 days|
|Cream cheese||2 weeks|
|Long-life milk||3 to 10 days, depending on brand|
|Mayonnaise (store-bought)||8 weeks|
|Pasta sauce||2 days|
|Pickles and chutney||8 weeks|
|Sliced ham||5 days|
|Smoked chicken||3 days|
|Smoked salmon||2 days|
|Sour cream||1 week|
|Soy milk||5 days|
|Tomato sauce||8 weeks|
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