How do I clean the odor out of a stainless steel travel mug?

Question

It says I can't put it in the dishwasher. I left milky coffee in it for too long and no matter how many time I fill it with hot soapy water it still has a noticable bad milk smell.

Answer 1

The best way to get that yuck out of there is sprinkle some baking soda in it then take a wet cloth or a bottle brush and wipe it with a bit of elbow grease, lol. then rinse clean. I promise this will work, my mom has to have her coffee and this is how she always cleaned/cleans her mugs after its set for a day to a few days. Good Luck.

Answer 2

Put some white vinegar and baking soda in some water and let set for a little while then wash with a bottle washer.

Answer 3

Why not combine Bert and Jen's suggestions then toss in a small piece of an abrasive pad, the type  used to clean badly soiled/stained cooking utinsels. Put the lid on the mug and toss in a car and leave for a few days. The movement of the car should keep the whole solution in motion thus cleaning the inside of mug. Don't fill the mug too full or you won't get the full effect of the agitation.