Ambergris was one of the most royal and rare foods in ancient China. They believed it to be the saliva of the dragons. However, it is excreted by whales when fat and bile forms in the stomachs of whales and it becomes hard after floating on the sea. It was said to be extremely tasty and the Chinese used it in special occasions.
Nowadays, Ambergris is rare due to decline in the whale population and it is even illegal in America.
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So is known as the only dairy dessert ever made in Japanese cuisine history. It was extremely popular in between 8th and 14th centuries and only noble people could afford it. It was a way to keep milk for a long time before the days of refrigerators. It must have tasted sour and concentrated.
So is so rare as cattle were always used for farming and pulling carts, never for milk and meats.
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