Drying and Roasting
The coca beans are spread under the sun for dry for over 2 weeks. Then, those beans would be shipped to chocolate factory countries for further process. Further process include Roasting, Pressing and Grinding. After these, bitter coca beans develop flavor and color. And they become coca powder or liquor, which is ready to be chocolate.
The process takes place in chocolate factories. As the map shows, the chocolate factories are pretty dense. Main chocolate factories, like Hershey, locate in U.S and Europe. There are much fewer in other states and region.
Roasting includes killing the harmful germs, preventing the organisms from growing and further developing the taste and the color of the chocolate. As I learned from the resources, the color development relies on the chemical reaction, known as Maillard browing. The maillard reaction will produce the brown color in the end. (water 7)