20. Saccharin
Constantin Fahlberg, a Russian chemist, discovered saccharin which is chemical compound commonly used in alternative sugar sweeteners. The chemist was working for Ira Remsen, a well-known chemist at Johns Hopkins University at the time of the discovery. While developing coal tar derivatives, the sweetener was accidentally discovered when Fahlberg went home and forgot to wash his hands. His wife had baked some biscuits that happened to taste sweeter than normal and after much deliberation and investigation, he realized it was one of the chemicals on his hands. After another taste test at the lab the next day it was determined to be the compound known today as saccharin. The jury is still out on the debate about whether or not artificial sweeteners are a healthy alternative, but this accidental invention has changed the sugar game.