If you have bought or seen a coffee bean/coffee powder bag, you will find out a object likes a button on the back of the bag,
there may be some small holes on it. That is the best device for coffee protection. it is called one-way degassing valve.
Oxygen, humidity, and temperature are the three major factors that affect the quality of coffee. How to make the oxygen in the
bag less and less is very important. The function of the one way degassing valve is to allow carbon dioxide to be discharged from
the bag and prevent oxygen from entering. This device, which can only go out and not go in, can effectively slow down the aging
rate of coffee.
During the roasting process, coffee beans will release part of the carbon dioxide, but most of the carbon dioxide remains in the
coffee beans, and the coffee beans will slowly discharge the internal gas about two weeks after roasting. If there is no one way
degassing valve to assist the exhaust, the coffee beans in the bag will continue to release the carbon dioxide, which will cause the
bag to expand excessively. In case of squeezing, it is easy to cause the bag to burst.
In addition, some people will squeeze the bag to smell the coffee, but this action will destroy the quality of the coffee beans.
When coffee beans exhaust the carbon dioxide, they will release a lot of aroma of coffee beans, which is why when the bag is
squeezed, the valve can smell aroma, but this is not the original design idea of the valve. The carbon dioxide in the bag is actually
one of the factors that keep the coffee beans fresh. The degassing valve is used to exhaust the air to control the speed of coffee
bean ripening. Once the air in the bag is emptied, it will accelerate the aging of coffee beans, so try to avoid squeezing bags to
smell aroma.
In addition to the above functions, the degassing valve also maintains the dryness and mellow flavor of coffee beans, and has a
moisture-proof function.
