Marmite

Repulsive "foodstuff" occasionally spread on bread by gomers too stupid, tasteless or poor to afford proper food.

Marmite is made of the crap they remove when brewing beer. Essentially it is industrial waste, but repackaged and sold at a hefty profit.

Anybody who enjoys the stomach-turning taste of Marmite's yeasty goodness may also want to consider having some pickle with that.