Since the roasted coffee beans will produce carbon dioxide, this valve can discharge the carbon dioxide from the coffee bag, and also prevent the oxygen outside the bag from entering the bag to oxidize the beans, thus ensuring the fresh quality of the coffee and eliminating the resulting coffee bag. Risk of swelling or bursting of the bulge.

In addition, the air valve is installed on the coffee bag, and the customer can directly squeeze the bag when purchasing, and the aroma of the coffee will be transmitted directly from the bag to allow the customer to smell its aroma so that the customer can better confirm the freshness (quality) of the coffee.

The ventilation holes of the “exhaust valve” of the coffee bag can isolate the intrusion of light and air outside the packaging bag so that the coffee beans can keep the fresh and original taste of the coffee beans in the best preservation and packaging state.

Therefore, it is very important to install a one-way exhaust valve on the coffee bag, and the Wojin one-way exhaust valve must be used on professional coffee packaging bags.