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For hundreds of years, the chocolate making process remained unchanged. When the Industrial Revolution arrived, many changes occurred that brought the hard, sweet candy to life. In the 18th century, mechanical mills were created that squeezed out cocoa butter, which in turn helped to create hard, durable chocolate. But, it was not until the arrival of the Industrial Revolution that these mills were put to bigger use. Not long after the revolution cooled down, companies began advertising this new invention to sell many of the chocolate treats we see today. When new machines were produced, people began experiencing and consuming chocolate worldwide.

Raimundo Madrazo's Hot Chocolate.

At the end of the 18th century, the first form of solid chocolate was invented in Turin by Doret. This chocolate was sold in large quantities from 1826 by Pierre Paul Caffarel. In 1819, F. L. Cailler opened the first Swiss chocolate factory. In 1828, DutchmanCoenraad Johannes van Houten patented a method for extracting the fat from cocoa beans and making powdered cocoa and cocoa butter. Van Houten also developed the "so-called" Dutch process of treating chocolate with alkali to remove the bitter taste. This made it possible to form the modern chocolate bar. It is believed that the English company, J. S. Fry & Sons made the first chocolate for eating in 1847, followed in 1849 by the Cadbury brothers.

Daniel Peter, a Swiss candle maker, joined his father-in-law's chocolate business. In 1867, he began experimenting with milk as an ingredient. He brought his new product, milk chocolate, to market in 1875. He was assisted in removing the water content from the milk to prevent mildewing by a neighbour, a baby food manufacturer named Henri Nestlé. Rodolphe Lindt invented the process called conching, which involves heating and grinding the chocolate solids very finely to ensure that the liquid is evenly blended. This enabled Milton Hershey to make chocolate even more popular by mass producing affordable chocolate bars.