In the process of roasting, coffee beans will produce some carbon dioxide. The carbon dioxide is only attached to the surface of the coffee beans at the start. So as the time of roasting and storage increases, the carbon dioxide will be released from the surface by degrees to support the packaging bag. The content of carbon dioxide affects the degree of roasting of coffee to a great extent. In most instances, coffee beans with a higher degree of roasting will emit more carbon dioxide. 100g of roasted coffee beans maybe produce 500cc of carbon dioxide, whereas relatively lower degree roasted coffee beans will emit less carbon dioxide. The release of a large amounts of carbon dioxide sometimes may break the packing of coffee beans, so consider the safety and quality, it is necessary to find a method to solve the carbon dioxide release. In addition, the coffee beans should not be exposed to oxygen too much simultaneously. So many clients choose to use coffee bags with one-way degassing valve.

Because there is a one-way degassing valve on the coffee bag, when coffee beans are roasted, they themselves will release carbon dioxide. If the one-way exhaust valve is not installed, the bag will expand, and even result the bag to explode in severe cases. Oxygen from the one-way exhaust valve cannot enter the inner bag, and extra gas can be exhausted through them as well. Now there is a packaging that is very suitable for coffee beans, plus a breathable valve, which can solve this problem very well. This breathable valve is a one-way degassing valve, which can just only allow the carbon dioxide of small molecules inside to be discharged, but the outside air cannot enter, in this way it can be discharged timely and when carbon dioxide is generated, the inner bag of the bag can also be released. Maintaining the oxygen at a low level to ensure the quality of the coffee.