The pH of vinegar (acetic acid) is 2.5, it is a weak acid. Vinegar is produced by a fermentation process from alcohol. In food, acetic acid reduces pH, controls microbial growth, and enhances flavour, it has the ability to preserve food.

Acetic acid also has functionality as a local antiseptic agent. Vinegar sold in supermarkets is diluted and is not pure acetic acid.

Using vinegar as a fabric softener

People love using vinegar in their laundry. There is an urban myth that it acts as a fabric softener. The chemistry of how fabric softeners work does not support this. found vinegar to be no more effective than washing in water alone.

Using vinegar with bicarb (baking soda)

People also love using vinegar and baking soda (sodium bicarbonate) for cleaning. When vinegar is combined with baking soda an acid-base reaction occurs immediately. This reaction is exothermic (energy releasing), followed by a rapid decomposition reaction, which creates water and carbon dioxide. The rapid decomposition means this method is not actually very useful for cleaning.

Using vinegar as a sanitiser and antibacterial product

4.2% acetic acid has been found to be effective against one type of fungus, Penicillium chrysogenum.

Unfortunately, there is no other evidence to support the use of vinegar as a broad-spectrum antibacterial product, at least not yet.

When vinegar is added to a large quantity of water, there is very little change to the pH of the water. The functional acetic acid component is diluted to a point that whatever anti-fungal properties it has, become ineffective, it will not sanitise.

Dissolving concrete dust with vinegar

In the laundry, vinegar is useful for dissolving concrete dust. The acidity of the vinegar dissolves the concrete dust. Use neat vinegar to clean filters and the inside of washing machines. 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 is effective and won’t damage the machine.