Why do Bags of Coffee Have that Valve in the Front

19 Jul 2020

"Eat it hot" is a sentence that often hear in life. Especially Chinese people do not like to eat cold dishes or meals. It proves that everyone loves the freshness of ingredients to some extent. People who pursue health have become another popular group in the society. For coffee, "hand punch" and "fresh grinding" have become a benchmark for saying goodbye to instant coffee, and "fresh" is a more avant-garde concept than the first two.

Fresh baked

The shelf life becomes very short when the coffee beans are roasted, which have only 15 days. One week after roasted would be the peak time of aroma and texture of coffee. After this point, the taste would weaken gradually, and disappear in the end.

The freshly roasted coffee contains the most nutrients, which means a stronger ability on preventing various diseases. If you have enough equipment, we recommend you grind and make coffee at home to better ensure the freshness of coffee. In other words, a good coffee mush be roasted freshly. Currently, more and more families like purchasing coffee in the supermarket and keep them at home. However, we know that the best taste period of coffee is comparatively short. So, does it mean that the coffee we purchased cannot be stored for a long time? Will the aroma lose quickly? In this case, our choice of coffee packaging is particularly important. Today, coffee roasting companies have a variety of packaging techniques, including vacuum packaging, gas filling or freezing, etc. The purpose of which is obvious is to avoid coffee oxidation. The reason is that the coffee needs to take some time to arrive to the café or supermarket after roasted. Even the company uses the best packaging method, the oxidization will still have impact on coffee due to the contact with air. Thus, they suggest consumers to drink coffee in a few days after roasted. Many coffee manufacturers consider coffee preservation issues and generally produce and use coffee packaging bags with coffee valves. So why do they choose to use a coffee valve? What effect does it have on coffee?

Coffee valve

The coffee valve is also called "one way degassing valve", it is a small accessory on the coffee package, which is hot pressed on the coffee bag by a professional valve pressing machine. Wojin Valve would share a small knowledge: once the coffee is roasted, it will produce gas (mainly the carbon dioxide) immediately. The carbon dioxide will be produced in larger quantities within 24 hours after roast process and will continuously eject in the following weeks. If we grind the coffee bean before putting them in the storage, the aroma of coffee will be reduced much more quickly because the coffee bean becomes smaller, which will accelerate the CO2 production process. The most important point is that the carbon dioxide will directly affect the texture and taste of coffee beans, and greatly reduce the freshness. In addition, the coffee roasting company is very clear that the sealed coffee bag expands until it breaks if there is no one-way degassing valve on the packaging. Thus, they must install a one-way degassing valve on the package to make the carbon dioxide released by roasted coffee discharge in time. That is also the popular reason that coffee needs to be degassed before drinking. Meanwhile, coffee will not easily oxidized and deteriorated with the installation of one-way degassing valve. Because the one-way degassing valve can not only discharge the internal gas, but also prevent the external oxygen and pollutant from entering in the bag. The function of one-way degassing valve perfectly protects the freshness of coffee and retain its best aroma and taste.

Tag: one way degassing valve

Originally published 19 Jul 2020, updated 19 Jul 2020.