What vinegar does in a wash

Short answer: Vinegar is a weak acid. It dissolves limescale, neutralises alkaline odour compounds and removes residue of detergent and fabric softener from the fibres. Used in small amounts in the rinse compartment, it can leave clothes cleaner and softer, but it does not replace the wash itself and does not suit every fabric.

Acid against limescale and soap residue

Limescale and soap residue are alkaline. A little acid in the rinse water dissolves them, so the fibres feel clean and soft without a film. When limescale sits in the textile, the fabric often feels stiff and heavy, and an acidic rinse can loosen it without adding another product that itself has to be rinsed out.

Some odour compounds are neutralised

Several of the molecules that smell of old sweat are alkaline. The acid turns them into compounds that smell less and rinse out more easily. That does not mean vinegar solves every odour problem, but it can help when the smell lingers after a normal wash. See bamboo tights for women.

Softener residue

Fabric softener can leave a greasy film on the fibres that holds on to both smell and dust. Using vinegar instead means the film does not form, and the fabric absorbs moisture better. That is especially an advantage for textiles that sit close to the skin and should draw sweat away.

How to use it

Half to one glass of ordinary household vinegar in the rinse compartment. The smell of vinegar disappears as the clothes dry. Start with the smallest amount and check whether the result is good enough. See bamboo underwear for women and all bamboo socks for women.

Why the rinse compartment

Vinegar belongs in the rinse compartment because it should work after the wash itself. If it is poured in the detergent drawer together with soap, the soap neutralises it and it does not do its job. Use a compartment that opens at the end of the programme.

What to watch out for

Rubber and seals in the machine can be affected by large amounts of acid over time, so keep to the small dose and run the machine empty now and then. If you have an older machine or one under warranty, look in the manual first.

Vinegar and smell in the wardrobe

The smell of vinegar usually disappears quickly, and the clothes will not smell of it once dry. If a faint scent remains, hanging the clothes in fresh air helps. Let them dry completely before putting them in the drawer.

When vinegar is not enough

If the smell sits deep in the fibres or a thick layer of fat has built up over many washes, vinegar alone will not help. Then wash at a higher temperature, use a detergent that breaks down fat, and let the garment soak first.

The routine of the season

Use vinegar when you notice clothes have gone stiff or the smell comes back, and not at every single wash. A fixed, simple routine is easier to keep. Note what works on your garments and stick to it.