Why I rinse the thermos before I fill it with soup

The soup is already in the pot — the hand reaches to pour it into the thermos “as is”. Inside sits yesterday’s tea or coffee: a dry smell, a thin film on the wall. I rinse the thermos first with hot water, shake it out, and only then pour the soup — otherwise by lunch a foreign taste rides along.

Why I rinse the thermos before I fill it with soup. Cooling soup before the cold is about a jar in the fridge; rinsing rice until the water runs clear is about porridge; a clean tasting spoon is about the pot. Here it is only the thermos before the pour: an empty flask without yesterday’s smell — not a speech about a new flask from the aisle.

If I already poured over dry tea — I tip it out, rinse once more and pour again. I don’t poke a soapy sponge “for luck” into a narrow flask. This note is only the thermos already by our hob — not a brand comparison.

I don’t need soup that tastes of yesterday’s tea. I need a clean flask and a quiet lunch. In your kitchen is the thermos rinsed before the soup — or already filled over a dry bottom?