What is the use of the air hole in the coffee bag? Coffee beans are easy to go away in the bag. Is it fresh?

I don't know if you have ever tried, holding the bulging coffee beans in both hands, the nose close to the hole in the coffee bag, squeezing hard, the fragrant smell of coffee ejected from the hole. The above description is wrong, children do not learn yo!

Small hole and great knowledge

There is a small hole in the bag of almost every bag of coffee. As soon as you squeeze the coffee bag, there will be delicious gas coming out (it's fun)!

In fact, these "small holes" are called one-way exhaust valves. As the name suggests, like an one-way street, the gas is allowed to flow in only one direction, never retrograde.

Why do coffee bags need an one-way exhaust valve?

Coffee is usually put into the bag as soon as the beans are roasted and cooled, which has the advantage of ensuring that the flavor of the beans is reduced. But as we all know, freshly baked coffee is very rich in carbon dioxide, and these gases will continue to be emitted for a few days.

Packaged coffee must be sealed, otherwise there will be no point in packaging. However, if the saturated gas is not emitted, the bag may explode at any time.

So I designed a small air valve which can only get out of this effect. The valve closes automatically when the pressure in the bag is reduced to not enough to open the valve disc. And only when the pressure inside the bag is higher than the pressure outside the bag will the valve open automatically, otherwise it will not be opened, and the air outside can not enter the bag. Sometimes, the release of large amounts of carbon dioxide may break the packaging of coffee beans, which can be avoided with an one-way exhaust valve.

(actual one-way exhaust valve device)

Squeezing coffee bags has an effect on coffee beans.

Many partners like to squeeze the coffee bag to smell the coffee, which will affect the flavor of the coffee. Because the gas in the coffee bag can also maintain the freshness of the coffee beans, when the gas in the coffee bag is saturated, it will inhibit the coffee beans to continue to emit gas, so that the whole exhaust process will be slower, which will help to prolong the taste period.

After artificially squeezing out the gas inside, due to the difference between the pressure in the bag and the outside world, coffee beans will accelerate the removal of gas to fill the space. Of course, the aroma of coffee that we smell when we squeeze coffee bags is actually the loss of flavor substances from coffee beans.

So, be careful, don't squeeze the coffee bean packing bag.