Got the missus to have a look, it is definitely a joke thing, Gesoeff basically means a rank drink, Teeloeffel means teaspoon, schaumkrone means the froth or head on top of a beer!
So, fill a glass with water, chuck some of this stuff in and wait for your mate to come back from the toilet, "There's your pint Dave!", "Oh, Cheers mate!" and hilarity will prevail! Who said the Germans haven't got a sense of humour!!