/diy/ - Do It Yourself

>>1757262
It is whatever you are putting in it. Likely coffee. Have you been using a bottle brush on it when you clean it? Picture related. OXO brand set you can get on Amazon for a 10 spot. Works well. I've picked up a few vintage vacuum bottles over the years and some people man, they don't even attempt to clean them. Open them up and the inside is solid brown and smells like death. If it is super nasty you can use something like Krud Kutter on it and it will dissolve in short order. The vinegar will probably do a good job but will take longer. Remember to get up around the shoulder area. Shit gets trapped in there and you really need to use a brush on it as you can't see it (without a dental mirror or endoscope at least) and it can make stuff taste bad when the bottle otherwise seems 'clean'.