Cocoa beans arrive at the manufacturer containing an assortment of impurities, such as stones, pieces of metal, twigs, and every type of foreign matter imaginable. Obviously these items must be removed prior to further processing. Cleaning takes place in stages and is accomplished by several methods, including sieving, the use of magnets, and the removal of dust to ensure the purity of the chocolate.
Historically, the blending of several varieties of bean at the manufacturer is another important step in chocolate production. In recent years, there has been a marketing effort emphasizing single-origin chocolate made from beans from one country, region, or even plantation. Opinions regarding single-origin chocolates vary. Some claim this chocolate to be of highest quality; others maintain that the best chocolate is made by mixing beans with different characteristics to create a chocolate with the most complex flavor. A case can be made for either argument, but, as with all things taste related, opinions on this matter are highly subjective. Each confectioner must choose chocolates based on their flavor profile and working characteristics and on economic realities.