There is nothing like having a thermos flask of hot coffee to help you through a long cold day. But to get a really clean flask is quite a task. Here's are some tips on how you can get them really clean:
Put in half an eggshell and two tablespoons of vinegar. Stand for a few minutes and then shake vigorously, add a glass of warm water and shake well again. The flask will become stain free. Fill up the flask with boiling water and add two tablespoons of soda bicarbonate. Shake well and leave it for a few minutes before rinsing. Put three tablespoons of soda bicarbonate in the thermos flask, fill with warm water, shake well and leave to stand for fifteen minutes. Rinse and leave to dry.
To get rid of the smell of coffee, and coffee stains, pour in a cup of boiling water and one tablespoon of raw rice, shake for a few minutes and rinse. Two or three lumps of sugar left in the thermos flask when it is not in use will prevent the development of a stale odour.
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