What is the function of the one-way exhaust valve of the coffee bag?

Since the roasted coffee beans will produce carbon dioxide, this valve can discharge the carbon dioxide from the bag, and also prevent the oxygen outside the bag from entering the bag to oxidize the beans, thus ensuring the new quality of the coffee and eliminating the resulting coffee bag—the 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 pack to allow the customer to smell its aroma, so that customer can better confirm the freshness (quality) of the coffee. 

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.