Monsooning of coffee beans is a special process. In an old time, coffee beans were exported from India to Europe by sailing boat and it took for many months to arrive.  Poor packed green coffee beans in a bad condition of hold of boat for long time turned to yellow color. Nowadays Monsooning coffee beans are purposely done by leaving out coffee beans in large open roof silo or open warehouse and exposed to the moisture of Monsoon winds for 2 seasons or so
The color of coffee beans turn to yellowish or light brown color. Acidity is suppressed and body is increase to heavy that makes unique taste.