'crusty' underams... sorry if TMI

[vole3]

Any hints on how to get rid of the crusty white residue from the underams of DH work tunics?
New job, so navy blue uniform, or navy blue with white patches....
Haven't changed deodorant from Mitchum as he's a bit of a sweaty herbert or non-bio washing stuff, have water softener plumbed in and usually use a 40 degree 1 hour wash.

Many thanks

[ELR]

i think white vinegar diluted is suppossed to work

[Starbear]

Yep vinegar