The first solid chocolate was not even close to being so fine and meltable as today. The first major development is attributed to Dutchman Conrad Van Houten, who invented hydraulic press in 1820. This invention enabled chocolate makers greater efficiency in mixing cocoa powder and sugar, so the texture of first solid chocolates was no longer so grain-like.
In 1856 Daniel Peter of Vevey Switzerland developed the first milk chocolate by adding milk to chocolate. The Swiss are also responsible for developing process known as “conching” during which chocolate turns into fine texture which melts in the mouth. This is because the tiniest particles of chocolate inside choncing machine are refined.