One of the topics in today's newsletter from Cookthink was soy sauce. I was surprised to learn that one of the ingredients I use when making beef jerky derived from leftovers. More precisely:
When the Chinese were fermenting soybeans for a flavoring paste in the 2nd century BCE, they realized that the liquids left behind were also pretty tasty.
Buddhist monks took the process to Japan, and by the 1600s it developed into the standard recipe of fermented soybeans and wheat we eat today.