Should You Be Adding Salt To Milk To Make It Last Longer?

Another day, another hack for reducing food waste – but food safety experts urge caution.
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With more people tightening their purse strings this winter, the nation’s focus is collectively turning to all the small ways we can make things stretch.

One money saving website is recommending that people add salt to their milk to make it last longer. But does this actually work?

According to Moneyboat’s list of 10 food hacks to make your weekly shop go further, you can make your carton of cow’s milk last that little bit longer by adding a pinch of salt to the carton immediately after opening.

This is because salt is a preservative, the site explains, so it deters bacteria from growing. “Do make sure to give the carton a good shake,” it advises, “and place it into the fridge as soon as possible.”

But food safety experts are urging people to take this particular hack with a pinch of salt.

Narriman Looch, of the Food Standards Agency, tells HuffPost UK: “We do not recommend adding salt to milk to preserve it for longer, but you can freeze milk to preserve it.

“We know many people are concerned about food affordability and food waste, so we encourage people to follow the date labelling and storage instructions on their food.”

Food safety expert Sylvia Anderson agrees. “In all the 35 years I’ve worked with food, I’ve never heard of that comment,” she tells HuffPost UK.

“I don’t think it would work, because the process [of producing the milk] is already done.”

Usually salt, sugar, oil and vinegar are added to products at the beginning of production to make the dish safe and stop bacteria from growing, she explains.

“So you know when you go to the supermarket and you buy a ready-to-eat meal and you have the traffic light system: green, yellow and red, and it will say it’s got salt, sugar, in it, etc. It’s not sprinkled on the top once it’s been processed, it’s done beforehand.”

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You can freeze milk if you’ve got a surplus and don’t want to waste it. According to the Dairy Farmers of Canada, unopened milk can be frozen in its original packaging for up to six weeks.

When you come to defrost it, simply pop it in the fridge and it should be thawed in about 24-36 hours, the group suggests, before advising to give the carton a “quick shake before opening” as sometimes the milk can separate. If you do find this happens, you can beat it with an electric mixer to get it back in shape.

From a safety perspective, it’s worth getting to grips with use-by and best-before dates. The FSA’s Narriman Looch explains that use-by dates are about safety, so if the milk has a use-by date, it can be used until the end of this date, but not after.

“You should not use the ‘sniff test’ on milk that has a use-by date,” he adds.

“Food can look and smell fine even after the use-by date has passed, but that doesn’t mean it’s safe to eat. We can’t see or smell the bugs that can cause food poisoning and make you sick.”

A best-before date, on the other hand, is about quality. For milk with a best-before date, you can check the look and smell to decide whether it’s appropriate to drink, he adds. “You can check if there are lumps or smell it to see if it smells bad.”

For Anderson, the key way to tell if milk has gone off is by pouring it into a cup of tea and coffee and seeing whether it separates. “If it splits, then you know it’s off,” she adds.

Ultimately, if you do find you’re wasting lots of milk on a weekly basis, it’s best to reduce the amount you buy.