Weißwurst shall be eaten before noon. Nowadays this is only and old tradition but when the Weißwurst was introduced 1857 there was no sufficient way to cool them. Since they were made always fresh in the morning you had to eat them before noon. Today this is not any longer issue but a nice tradition. Some places stick to the tradition and will not serve Weißwurst after noon. So Weißwurst became a breakfast /brunch item which is traditional combined with a Weißbier.