The moisture content of coffee beans can determine the resulting quality of a brew. This is why it’s important to make sure that each batch of harvested coffee has just the right moisture content, which is recommended to be at around 11.5% when the beans are ready for storage and shipping. Considering that various circumstances such as climate and altitude in different regions of the world would also affect coffee’s moisture content, it’s essential to take note of the proper way of handling the beans in all the stages of processing.


Mishandling or neglecting the beans during the drying stage can be disastrous for farmers and roasters alike. Taking care not to overexpose the beans is a must during the drying process, while under-drying can cause plenty of problems as well.


black coffee beans processing


Over-drying can cause irreparable damage to the coffee beans such as the loss of quality in terms of aroma and acidity, giving way to reduced flavor and taste. At the same time, the beans may become too brittle and can break easily when milled. Over-drying can also reduce the freshness and color of the beans, which would translate to a loss in quality and a reduction in price.


Moreover, roasters who handle coffee with not enough moisture content can over-roast the beans, resulting in burnt coffee and loss of profit. This is why gentle slow-drying is needed while constantly monitoring the state of the beans.


post harvest wet coffee processing from machine


Related: A Beginner's Guide to Roasting Coffee


When under-dried on the other hand, coffee beans can develop molds because of the excess moisture. The growth of these toxic fungi on coffee beans can bring health risks to those who ingest them. Substances such as aflatoxins and mycotoxins can become prevalent in under-dried coffee. These substances are known to be carcinogens and can potentially cause damage to all internal organs, especially to the kidneys and liver. Ensuring that no mold growth occurs is a crucial part of processing coffee.


Be it through netting, patio drying, or using drying racks, it’s recommended that no matter what the drying method, handlers should always monitor the moisture content of the beans. The use of sanitary facilities in handling and storing coffee is important to make sure that impurities are not blended into the beans. Solutions such as hermetic technology provided by GrainPro are perfect tools for ensuring that coffee is protected from farm to cup.


Related: How to Perfectly Dry Green Coffee Beans


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Date Published: October 3, 2018

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