How to Tell if Milk is Off – Try The Sniff Test

Want to know how to tell if milk is off?  Let me share with you the very best method so you’ll never unnecessarily waste a drop again.

I’ve talked before about expiration dates on eggs, and how to check to see if you can eat them past their date.  

But what about milk?  Food waste is a huge problem.  Particularly when it comes to milk.  Here in the UK, a huge one in six pints of milk is thrown away each year.  This is problematic because, in terms of carbon emissions, land use, water use, dairy milk has the biggest impact on the planet.  Wasting less milk where we can is therefore incredibly important. 

Morrisons announced in January 2022 that they are scrapping use by dates on milk. This is great news because this will save millions of pints of milk from being thrown away unnecessarily every year. This is because, when it comes to milk, the use-by date isn’t a great indication of if your milk is usable or not. Instead, bottles of milk sold by Morrisons will still carry “best before” dates. These will give an indication of when the milk will have the best taste, but can often still be used safely for several days after that point.

So, if your milk has reached its expiry date and you’ve still got some left then how do you tell if milk is off? Or if it is still safe to drink?  Do you sniff the carton to see how it smells?  If you do, then what if I tell you then that you’ve been doing it all wrong?

Why The Carton Sniff Test Is Wrong

It’s true.  If you’ve been sniffing the carton/bottle to tell if your milk is off, then chances are unless the milk is definitely off, then you will have been getting a false picture of how the milk actually smells.  

Instead of the milk, you’ll actually have been getting a whiff of the horrible dried-up bits of milk around the rim of the carton.  This may have perhaps caused you to bin the milk unnecessarily early.

My 99-year-old grandad has scant regard for expiration dates on food.  Want to know a true story? Some time ago he found a tin of tomatoes 10 years out of date in the back of his cupboard.  A lesser person might have put the can in the bin.  But no, not my grandad. Nope, he used the tomatoes to make them into tomato soup and ate it regardless.  And you know what?  He was perfectly fine! 

His rule for how to tell if milk is off is simple but dubious.  If he puts milk in his tea or coffee and it curdles then it’s off.  If not, then the milk is fine for consumption, regardless of the date on the carton.

I personally think my grandad’s milk testing method is a bit extreme.  I mean, who wants to potentially waste a perfectly good cup of tea?

So What Is The Best Method To Tell If Milk Is Off?

I disagree with my grandad. In actual fact, the best way to tell if milk is off or not is to pour a little bit of milk into a clean glass.  Then sniff the milk in the glass. If your milk is off, you’ll smell a sour smell indicating that the milk has spoiled.

The glass method gives you a much better idea of if the milk is off or not. This way the dried-up bits of milk around the rim aren’t going to throw you off the scent of fresh milk.

Of course, if in any doubt, do look to see if your milk has curdled. This means you should look for lumps that formed in the milk. If you see any, this is a sign it should not be used.

I find this method fail-safe – you’ll never throw out perfectly good milk again!

Do also remember that milk’s life can be extended by keeping it cool in the fridge. You should also keep milk bottles closed as much as possible.

Do you have any tips to reduce food waste?  Do share in the comments below! And if you’re thinking about switching to oat milk, then here’s my guide to the best oat milk.