Why vinegar is so good at cleaning

Vinegar is a staple in housekeeping hacks and cleaning tips. BBC Future looks at why it might just be the most useful product in your pantry.
 

All it took was some white vinegar, a rubber band and a Ziploc bag. Within 25 minutes, the limescale encrusted onto a metallic bathroom tap had become so soft, it could simply be wiped it away with a toothbrush. The hack is part of a viral trend on social media – #CleanTok – involving online gurus sharing simple tricks with satisfying payoffs, as dirt is erased to reveal sparkling surfaces.

But though there are thousands of commercial cleaning products out there, many influencers choose to use vinegar. From de-greasing windows to washing strawberries or transforming toilets, it seems there is nothing this household ingredient can't do. It's being added to dishwashers, washing machines, and even used by scientists to disinfect laboratories. But what makes it so versatile?

Vinegar is made via a two-step fermentation process. First, carbohydrates of any kind are fed to yeast cells, which turn their sugars into alcohol and carbon dioxide. This alcohol is then exposed to oxygen and fermented again, this time with the bacteria Acetobacter instead of yeast, and voila – the alcoholic liquid is turned into a mixture of water and acetic acid. It's the same phenomenon that produces the sour flavour in wine that might have been accidentally been left open overnight.

When it comes to cleaning, vinegar's most useful asset is arguably its acidity – mild enough to not damage fabrics and surfaces, but strong enough to get rid of stubborn stains and deposits. The household staple can have a pH as low as 2.2 – around 10 times as acidic as the average soft drink. Commercial vinegar tends to fall on the lower end of the range, while homemade versions have a pH of around 3. When vinegar is added to stains, particularly those caused by mineral deposits such as limescale – a chalky build-up consisting mainly of calcium carbonate – the acid helps to breaks it down. The reaction produces a salt – calcium acetate, which readily dissolves in water – and carbon dioxide.

The other advantage of vinegar is its antimicrobial properties. While some highly specialised bacteria can survive in acidic environments, most everyday ones find it difficult to survive and replicate in these conditions. Enter pickling, an ancient method of preserving food by creating an inhospitable environment using salt and vinegar. Cleaning with vinegar relies on the same logic, and research has found that it can kill a range of pathogens, including E. coli. The product has been found to be effective for a wide range of uses, from cleaning dentures to disinfecting fruits and vegetables.
 

Another popular cleaning hack is to apply vinegar to a surface that needs to be cleaned, then sprinkle on some baking soda and watch as it foams up – the same trick used to make the "lava" for volcanoes at school. In this case, the reaction produces water and carbon dioxide bubbles, which interact help to physically break up dirt. As a "base", a substance that will react with an acid, baking soda is also useful for drawing grease and stains into the cleaning liquid – it makes the organic molecules within them more soluble in water.

However, there is one situation where vinegar should never be used: on certain types of stone. Adding vinegar to limestone, travertine or onyx floors, worktops or tiles will replicate the baking soda reaction – these rocks contain calcium carbonate, which is also a base. As the acetic acid in vinegar gets to work, you'll end up with a beautifully clean surface – with holes in it.

Can vinegar be used for cleaning electronics?

Vinegar isn't recommended for cleaning the inside of electronic items because it's an acidic liquid which can corrode metal parts. The exterior of unplugged laptops and computer equipment can, however, be safely wiped down with a mix of distilled water and vinegar sprayed on to a microfibre cloth – spray onto the cloth and not the electrical item, and don't plug it back in and turn it on until the streaks have dried.

Even laptop and phone touchscreens – normally a no-no for harsher, alcohol-based cleaners – can be cleaned with this approach. But the impurities in vinegar, which mostly consists of undistilled water, can present problems if it's used on circuit boards.

However, one realm where vinegar is a staple – film camera repairs. Cameras stored for a long time with batteries often suffer catastrophic battery leakage which can stop the camera working. Vinegar, it turns out, is the solution, says Tokyo-based camera dealer Bellamy Hunt. "You don't need much, just a Q-tip and some patience," he says. "And a sense of wonder as the acid gently removes the corrosion, leaving your Q tips a blue green. Science in action.

"For the battery compartment there is no better or cheaper alternative. Unless of course you have a lemon tree in your garden."

Australian camera repairer Brett Rogers says it has other uses too. "It is good for removing odours from really dirty kit, like gear that has lived in a smoker's house for years. That can be gross. Usually I prefer to attack exterior dirt and grime with a cloth and a little isopropyl. But if something is really gross, out comes the vinegar.

"I have also used it on a few lenses that had severe haze. It is not my first recourse. But if I have a real problem case and a lens is so bad there is nothing to lose I'll try acetone or vinegar." Vinegar is a very effective mould killer and the interior of camera lenses can easily become infested in humid conditions; Rogers warns that even diluted vinegar can be too harsh for some lens coatings, so tends to use it on more modern optics.

Can vinegar banish odours?

The acetic acid in vinegar is itself highly pungent and one that not everyone finds pleasant. It is a common component in body malodours, for example. But as a mild acid, it will also readily react with odorous alkaline chemicals (bases) such as ammonia, which create the strong smell in concentrated urine, and trimethylamine, which has a distinctly fishy odour.


Some cleaning enthusiasts recommend boiling a pan of vinegar to help get rid of strong odours by turning the acetic acid into a vapour that might more readily react with any volatile bases in a room. But concentrated acetic acid vapours can also irritate the airways and eyes. Then there is the lingering smell of vinegar throughout your home.

An alternative might be to treat the offending surfaces with vinegar instead. The strong odour left by fish, for example, can be neutralised by washing with a mild acid such as vinegar. It reacts with the amines in the fish oils to form salts that cannot become airborne and offend the nose. But lemon juice – which contains citric acid rather than acetic acid – is often recommended as a more palatable alternative, especially when it comes to getting the smell of fish off the hands.

Some vinegars – such as wood vinegar, which is far more pungent that the household malt and wine kinds – have even been found to be effective at neutralising the powerful stench from pigsties.

So, vinegar can have a range of household uses, though there are some situations where it might be best to opt for a commercial alternative. And whatever you do, don't use the balsamic kind – unless you want to spend hours scrubbing out that stain, too.