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What is the hole in the coffee bean package? understanding the exhaust hole in the coffee bean package

Published: 2026-04-04 Author: World Gafei
Last Updated: 2026/04/04, Professional coffee knowledge exchange more coffee bean information please follow the coffee workshop (Wechat official account cafe_style) Italian exhaust valve invented by Goglio Luigi-Milano S.p.An in the 1960s, widely used in flexible packaging, won many awards: 1968 Italian Packaging Academy Award 1968 European Star Medal 1970 World Packaging Organization World Chapter 1

Professional coffee knowledge exchange more coffee bean information please follow the coffee workshop (Wechat official account cafe_style)

Italian exhaust valve, invented by Goglio Luigi-Milano S.p.An in the 1960s, is widely used in flexible packaging and has won many awards:

1968 Italian Packaging Award 1968 European Star Medal 1970 World Packaging Organization World Medal

Let's bring you to know this exhaust valve!

If you have looked at the coffee bean bag, you will find that there is an object on the back that looks like a button, and there may be a small hole in it, called an "air valve".

The purpose of this device is to remove carbon dioxide from the bean bag, because freshly roasted coffee beans have to be vented, which is more aptly said to feel like breathing.

The function of the air valve is to help release the carbon dioxide from the coffee beans, so for the coffee beans, the air valve is a device that keeps the air out, effectively slowing down the aging rate of the coffee beans.

Fresh coffee beans release carbon dioxide

In the process of roasting coffee beans, part of the carbon dioxide is released, but most of the carbon dioxide remains in the beans, so the beans slowly vent the gas after about two weeks of baking.

At this time, if the bag containing coffee beans does not have an air valve to assist in exhaust, the coffee beans in the bag will continue to exhaust, which will cause the bag to over-expand. If the storage environment causes compression, it may cause the bean bag to burst, thus destroying the preservation of the coffee bean. (it may take you half a day or several days to realize that the coffee beans have gone bad due to exposure to the air.)

The harm of air to coffee quality

At the beginning, it is mentioned that the air valve of the coffee bean bag is a device that does not enter and exit only, that is, the one-way valve. The function of the valve can not only discharge the gas from the coffee beans, but also prevent the outside air from seeping into the bean bag, affecting the quality of the coffee beans.

There are three major factors that affect the quality of coffee beans: oxygen, humidity and temperature, which will shorten the best taste period of coffee beans and destroy the quality of coffee beans. Therefore, it is very important to discharge the internal gas without letting the air in.

FrontStreet Coffee is a long-established specialty coffee roaster in Guangzhou China, selling freshly roasted beans from its own farm in Yunnan as well as dozens of carefully selected single-origin beans from around the world for both pour-over and espresso. The products deliver consistently excellent quality and great value, with shipping within 24 hours. Guangzhou’s FrontStreet Coffee shop is recommended by many coffee lovers, and the beans are now available online at the Tmall 。

Important Notice :

前街咖啡 FrontStreet Coffee has moved to new addredd:

FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473

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