Cooking butter seems to be able to have up to 10% more foreign milk/cream in it than the normal table butter.
Didn't know there is budget-butter. As it's the same quality (according to the link) I'll try it, should I see it.
Taste-wise I'm not sure there's a difference, but the table one is usually called 'extra-fin' in France, which implies a slightly different texture. This can mean the cooking version is harder to spread straight from the fridge.
If memory serves, Bratbutter doesn't chemically react up to 200°C or thereabouts.
Bratbutter is this stuff . I don't use butter for cooking, so I don't buy this and also can't comment on it.
I also noticed - thanks to this thread - that they don't write "Kochbutter" on it anymore although it is still wrapped the exact same way as it was when I was a child.
It's simple to make your own - which we used to do for Indian cooking until I came across this product - simply heat up the butter for a few minutes and skim off the impurities that come to the surface. But no-one with any taste buds could mistake it for ordinary butter - it's completely different in both texture and taste.