Well, I don't drink since more than 20 years and all my experience is either theoretical or by memory :wink: .
However, I'm rather sure that 'Blume' is the name of the froth/foam on top of a Plis (beer).
[Knowing only Elbschlößchen, Astra or St.Pauli-Bavaria-Pils, hamburger, I can understand that you never heard of that
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