21. Norbert Rillieux (1806-1894)

Notable invention: Multiple-effect evaporator

 This American engineer revolutionized the sugar industry with the multiple-effect evaporator, a device that produced high-quality sugar and reduced production costs by using steam efficiently to evaporate water and prevetn sugar from burning or being discolored. After patenting his creation in 1843, sugar manufacturers from Cuba to Egypt requested Rillieux’s machine. It’s still used today to make glue, soap, milk, and other products. Sweet.