Using vinegar in the laundry

People across the internet love using vinegar for cleaning, removing mould and as a fabric softener replacement. Let’s look at the chemistry and whether any of these recommendations hold truth.

We are a source you can trust, combining science expertise and hands-on cloth nappy experience. Our team of qualified chemists and health professionals develop and test all our advice.

What is vinegar

Vinegar (acetic acid) is produced by a fermentation process from alcohol. It is a weak acid with a pH of 2.5. Vinegar is at least 4% acetic acid by volume; the rest of the solution is water. Most vinegar sold in the supermarket is 4-8% acetic acid.

In food, acetic acid reduces pH, controls microbial growth, and enhances flavour. It can also preserve food.

Vinegar does not sanitise

Acetic acid also has the functionality of a local antiseptic agent. It is important to remember that vinegar is diluted acetic acid, it does not have the same properties as concentrated acetic acid used in laboratories.

Vinegar does not sanitise. When vinegar is added to a large quantity of water, there is very little change to the pH of the water. This is because the already diluted acetic acid component is further diluted to a point that it becomes ineffective.

Vinegar has limited effectiveness with mould

It is a common myth that vinegar (diluted acetic acid) is effective at killing all types of mould. Currently the only mould that can be partially killed by straight vinegar is Penicillium chrysogenum. Most household moulds are Aspergillus species.

There is no other evidence to support the use of vinegar as a broad-spectrum antibacterial product or mould killer.

The fallacy of vinegar with bicarb (baking soda)

People across the internet love using vinegar and bicarb soda (sodium bicarbonate) for cleaning. When vinegar is combined with bicarb soda it creates water and carbon dioxide.

The carbon dioxide fizzes and bubbles away, leaving behind a mixture of sodium acetate and water. Although this fizzing looks impressive, it is not that useful for cleaning.

Vinegar is not a fabric softener

People love using vinegar in their laundry. There is a prevailing urban myth that it acts as a fabric softener. The chemistry of how fabric softeners work does not support this.

Using vinegar to dissolve slime

Vinegar is an effective cleaner for removing slime from fabric. It breaks down the stickiness of the slime, particularly the glue used to make it.

Saturate the affected area with vinegar and water, let it soak, and then use a brush or cloth to work the slime loose

Dissolving concrete dust with vinegar

Vinegar is also useful for dissolving concrete dust. The acidity of the vinegar dissolves the concrete dust.

If your washing machine has concrete dust, use neat vinegar to clean the filters and the inside of the machine. However, only do this if is absolutely necessary as neat vinegar is corrosive and will eventually damage seals and other parts of the machine. Other machine cleaning methods such as a drum clean cycle or dilute bleach wash are also effective and won’t damage the machine.