Most of us would check the dates on a packaged food before making a decision on whether to keep or toss it out. But do you know: Dates on food labels are the manufacturers’ best guess about how long a food will taste freshest; after that date, the quality gradually declines. Most date labels tell you about a food’s quality, not safety, US food experts say.

“There is nothing concrete for these dates related to food-borne illness,” said Dr Andrea Glenn, a postdoctoral research fellow and registered dietitian at the Harvard TH Chan School of Public Health.

“These dates generally refer to when a product will have the best flavour or quality or when to sell the product by and are not related to safety of the food,” a Guardian report cited her as saying.

It’s far more useful instead to look for signs of spoilage. Odd or off odour, flavour, colour or texture are better indicators of potential danger.

How to know if food is spoilt? An article in Food Insight gives the following tips:

> Food that is abnormally soft, discoloured or has an uncharacteristically unpleasant odour is likely spoiled and should be discarded.

> Food that has moulded or has developed a “slimy” film on it should not be eaten. Even if you remove the mould or slime, lingering microbes can still pose a foodborne illness threat.

> In the case of canned goods, swollen cans often indicate a spoiled product.

> If in doubt, throw the food away. It is better to be cautious than to eat potentially unsafe food.

(Illustrations: Food Insight)