Coffee

In detail

Coffee stains with polyphenols and tannins, the same broad family that colours tea and red wine, which is why the three behave alike on textiles and why none of them yields to detergent the way an oily soil does. A surfactant lifts what is sitting on a fibre; a tannin that has bonded to one is not sitting on it. The carpet trade's sequence is instructive because it is a sequence rather than a product recommendation: a weak detergent solution first, and a white vinegar solution only if that has not finished the job, followed by a rinse with cold water and blotting until no moisture remains. Two details in that guidance carry more information than they appear to. The dilution is emphatic — a quarter teaspoon of liquid dish washing detergent per cup of lukewarm water, with the explicit instruction never to use a stronger concentration — which is a statement about what damages carpet rather than about what cleans it. And laundry detergent and automatic dishwasher detergent are ruled out entirely, because they can damage fibres or cause discolouration. Heat sets this class of stain, so a hot wash before the mark has gone makes it substantially harder.

What works

• Sodium bicarbonate is effective against Coffee Supported

  Sprint 29. And the distinction is the point: bicarbonate for the coffee deposit, washing soda for the tannin.

Hacks and claims involving this

• A stronger solution cleans better Does not work
• Using laundry detergent on a carpet stain Does not work
• The care label allows oxygen bleach even when it bans chlorine Does not work
• A stain method that works on cotton works on anything Does not work