That bag of fresh salad leaves you purchased just three days prior a few handfuls taken, the rest left to curl up or turn slimy - is often tossed straight from the fridge into the bin.

Despite an attempt to salvage the still-crisp leaves, the outcome usually results in waste. With bags priced anywhere from 69p to well over a pound, the annual cost of discarded greens can quickly add up. Many individuals may have chucked out hundreds of pounds worth of salad leaves over recent years. Nonetheless, there's a trick that everyone should consider before hurling any limp leaves today.

James Rogers, director of food safety research and testing at Consumer Reports, advises that even cold water washing doesn't rid vegetables of bacteria. On the Consumer Reports website, he mentions that consumption of leaves adjacent to rotten ones is generally harmless.

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He said: "As gross as slimy greens are, the good news is that the damage caused by age and spoilage bacteria is unlikely to make you sick if you pick out the slimy bits-or, indeed, even if you eat a slimy piece by mistake. I am not going to say absolutely not, because there are exceptions to the rule. There are some people who are very sensitive to eating spoiled food."

According to Mr Rogers, it's also plausible for leaves to harbour more harmful bacteria even before showing signs of spoilage. He explained: "Our leafy greens have a lot of bacteria on them-because of the way they're grown, the soil, the air, the animals that walk through the fields.

"And those bacteria can include types that can cause serious foodborne illnesses, including Salmonella, Listeria and pathogenic strains of E. coli." However, he reassured that boiling these greens would eliminate these harmful bacteria, reports the Express. He recommended either quickly blanching or stir-frying them to kill off the bacteria.

But be cautious if they are overly slimy and producing liquid. Interestingly, if you don't manage to eat all your salad leaves in a day or two and find half a bag left with some starting to curl up and go slimy, you can still cook with them.

I experimented with a bag of past-their-best leaves that I didn't want to waste and tossed them into a tomato pasta sauce I was preparing, writes Jon Austin from the Express.

Within minutes, they wilted down to something resembling spinach. For my next experiment, I simply boiled a bag of leaves, resulting in a dark green pile of spinach-like leaves. Add some salt and pepper, garlic, or any other flavours to taste.

These cooked leaves can be used as a substitute for ingredients like spinach in Indian dishes such as sag aloo. The crispier, iceberg-lettuce type leaves don't work as well, but can be chopped up and they blend in nicely. Once you give it a go, you'll never turn back, and crucially, you'll never waste salad leaves again, saving both money and food.

In the video, I whipped up some wilted pea shoots that were a few days past their use-by date for the first time. It took a tad longer to boil due to the stalks, but the final product was so delicious it could be eaten on its own.

The great news is that experts reckon boiling them should kill any bacteria that might have started to form, and even any that were present when the produce was purchased.