Things You'll Need
Packing your morning coffee in a thermos and taking it to work is an excellent idea. It saves you money from stopping at the big name coffee store every morning. Also, the thermos can hold more coffee and keep it hot much longer. The only downside to using a thermos for your coffee daily is that it begins to get stained and contain a permanent coffee odor. However, you can use bleach to get rid of this stain and remove the odor.
Pour 1/8 of a cup of bleach in to your thermos. Bleach is strong stuff and you won't need that much of it to get your coffee thermos clean.
Add 1 tsp. of your favorite dish detergent. The particular brand doesn't really matter in this case.
Fill the thermos up the rest of the way with hot water.
Let the thermos sit for 30 minutes. This gives the bleach and detergent some time to soften up the brown stains inside the thermos.
Use a bottle brush for infants baby bottles to remove any dirt inside the thermos. You will want to move the brush quickly up and down all around the inside of the thermos.
Dump the liquid out of the thermos and inspect it to make sure that it is clean. If not, spend a few more minutes working on it with your bristle brush.
Rinse the thermos out thoroughly with hot water. You want to make sure that all of the soap and bleach have been rinsed away so you don't taste them in your coffee the next morning.
Wipe the outside of the thermos and the lid down with a soapy wash rag and rinse clean.
Dry with a towel immediately afterward. This will give your thermos a nice shine.
If you have a stainless steel thermos, you can clean the outside with a little Windex and a paper towel.
Don't wait a year to clean your coffee thermos. It is best done at least once per month.