Abigail Tucker presents some interesting historical facts about the traditional cake served at a wedding in the West:
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One early British recipe for “Bride’s Pye” mixed cockscombs, lamb testicles, sweetbreads, oysters and (mercifully) plenty of spices. Another version called for boiled calf’s feet.
By the mid sixteenth century, though, sugar was becoming plentiful in England. The more refined the sugar, the whiter it was. Pure white icing soon became a wedding cake staple. Not only did the color allude to the bride’s virginity, as Carol Wilson points out in her Gastronomica article “Wedding Cake: A Slice of History,” but the whiteness was “a status symbol, a display of the family’s wealth.” Later, tiered cakes, with their cement-like supports of decorative dried icing, also advertised affluence. Formal wedding cakes became bigger and more elaborate through the Victorian age. In 1947, when Queen Elizabeth II (then Princess Elizabeth) wed Prince Philip, the cake weighed 500 pounds.
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Its now usually only ever about wealth. The bigger, more illustrious and well decorated cakes cost more. Its the perfect one time (usually) opportunity to go all out and impress your friends.