But it sounds like an unlikely urban legend, doesn’t it? And who’d want to put something with such an intrusive odour onto their jeans?! Like Danny Hodgson from Rivet and Hide, many hate the smell of vinegar, which is why he’s never used it.
Indigo and sulfur (the two most common denim dyes) are ‘unstable,’ meaning the colour bleeds when washed as the dye releases pigmented mineral compounds. Vinegar absorbs and neutralises these minerals.
But vinegar does more than retain colour. It kills bacteria and that it works as a biodegradable fabric softener. But, although vinegar technically does kill bacteria, the dosage you use in domestic laundry is so small that it won’t make much of a difference.
Gordon of Blue in Green says there are examples of vinegar working as a fabric softener, but adds that it also depends on how the garment is dried. With line drying, you often get a stiffer hand compared to machine drying, which softens the denim up due to the agitation and tumbling.
MYTH STATUS: CONFIRMED