A useless knowledge point: the "vanilla flavor" in ice cream was first taken from the fruit of the vanilla orchid native to Mexico, which is often called "vanilla beans". Vanilla pods need to be processed through complex processes such as killing, fermentation, drying, aging, etc., and the process takes half a year, so natural vanilla pods are sold at the root, which is expensive.
Later, it was discovered that "vanillin" could be artificially synthesized with "guaiacol" and "lignin", so the affordable "vanilla flavor" (Yun Na) rotted on the street; In the sixties and seventies, vanilla flavor was the most basic default taste of almost all ice cream, and it was even regarded as the original flavor of ice cream.
For this reason, the word "vanilla" not only means "vanilla" in English, but also derives the meaning of "ordinary", "simple", "most basic" and "original", such as: vanilla bond (pure bond), vanilla option (simple option), vanilla convolution (original convolution), vanilla sex (bland and uninteresting snap).
