In 1765, the Scottish inventor James Watt built a steam engine that made goods quickly and cheaply. Using a steam - powered chocolate grinder made chocolate a cheaper treat for everyone. In 1828, the Dutch chemist Conrad van Houten invented a chocolate press and this made the chocolate taste better.Cocoa beans are made up of cocoa mass and fatty cocoa butter. Cocoa butter makes the chocolate greasy and doesn't mix well with water. The chocolate press separated out much of the cocoa butter. The result was chocolate that had a purer flavour and mixed easily with water.