Bean Moisture
It helps to use an effective moisture analyzer, which can be purchased for less than $900. To prevent roasting imperfections, the green bean moisture content should be between 10 and 12.5 percent. Green coffee beans usually
become too dry (8–10 percent moisture) or too humid (12.5–14 percent) as a result of improper storage conditions and environmental factors. Think of warehouses in regions with sub-tropical, humid conditions or regions with bone-dry, hot climates. High-moisture beans should be roasted very gently in the first stage and low-moisture beans must be watched
closely because of the risk of an uncontrollable acceleration throughout the process. I also recommend recording the moisture content of all green beans frequently.