Processing of coffee is the method converting the raw fruit (cherry) of the coffee plant into the commodity green coffee. The cherry has the fruit or pulp removed leaving the seed or bean which is then dried. While all green coffee is processed, the method that is used varies and can have a significant effect on the flavor of roasted and brewed coffee. There are several processing methods of coffee: Wet process, dry process, semi dry process. Here let's focus on dry processing.
Coffee Drying Stages
In a study done in Kenya, Kamau reports that there are six stages to drying coffee.
1) Skin drying. Moisture 55-45%.
2) White Stage drying. Moisture 44-33%.
3) Soft Black stage. Moisture 32-22%.
4) Medium Black Stage. Moisture 21-16%
5) Hard Black Stage. Moisture 15-12%
6) Fully dry coffee and conditioning. 11-10%.
Coffee Drying Equipment
There are several coffee dryer systems available. Many older dryers are converted grain dryers that are not as efficient as the new horizontal barrel dryers. The new coffee dryers are designed to mix the coffee evenly to ensure uniform drying. Drying coffee by using mechanical dryers accelerates the slowest part of the coffee drying process (15-11%) and helps prevent fermentation. In some environments that have a high humidity the entire drying process must take place in mechanical dryers. Mechanical dryers should never be set higher than 40-45°C and this question should be asked before buying any coffees that have been mechanically dried. At higher temperatures the germ is killed and the flavor potential of the coffee is ruined. At extreme temperatures the bean crystallizes, and when smashed with a hammer, will break like glass.
Besides, we also produce :  fluid bed dryers, airstream dryer, spray dryer, vacuum and conductive style dryer, oven style dryer, v mixers.