In daily life, many people don’t know that coffee is a kind of high-quality drinks with delicate taste. After drinking, coffee should be immediately separated from oxygen and moisture so as to extend its freshness preservation. Therefore, coffee packaging requires a composite packaging bag with low oxygen transmission rate plus heat-seal and it is 100% seal.
Multilayer composite film with aluminum foil can mutually play a best preservation effect. The baked coffee will release a lot of carbon dioxide in two or three weeks. So how to keep the coffee in a sealed, air-isolated place and discharge the carbon dioxide from the packaging bag. Of course, it is necessary to use one way degassing valve on the packaging bag. The quality of measuring the packaging bag and one way degassing valve lies in its ability to maintain low oxygen content in the bag. Less than 1% is preferred, while less than 5% is the basic requirement.
Wojin one way degassing valve is welded in the packaging bag by using Wojin VM01 valve pressing machine in the way of heat-pressing. While heat pressing, three holds are punctured on the packaging bag. Sometimes, two to six holds can be customized according to the customers’ requirement. When the carbon dioxide released by the baked coffee bean have reached the set pressure, the gas will be discharged through the one way degassing valve but the outside air can never entered into the packaging bag. So the packaging bag has the function of exhausting and anti-oxidation. At present, it is widely used in coffee bad and fermented feed bag.
Because a one way degassing valve is set on the top of the plastic packaging bag, in the process of stacking, the residual air in the lower bag is discharged from the one way degassing valve under the weight of the goods in the upper packaging bag, which can improve the stability of stacking and increase the height of stacking.
One way degassing valve has improved impact resistance of the packaging bag. When carrying or falling from height, the inside air of packaging bag filled with goods can be released through a one way degassing valve to reduce the shock wave from residual air in the bag and reduce or avoid the resulting breakage.
There are a lot of buyers confused, said that so much about the benefits one way degassing, which one should we choose, if our coffee powder need a one way degassing valve for packaging bag. We suggest you to choose the one way degassing valve with filter. Because coffee powder is small particles and Wojin one way degassing valve WJ1901 is a degassing valve with filter which is suitable for powder articles like coffee powder. With a filter, the small particle will not be exhausted out of the bag but can prevent the air from entering into the packaging bag, causing oxidation.
What about packaging bag for coffee beans? Which valve should we choose? We suggest you to choose the one way degassing valve without filter. For example, Wojin one wat degassing valve WJ1902 is a kind of one wad degassing valve without filter which is suitable for large particles like coffee beans.
If it is the other products with volatile gases in the packaging bag, the corresponding one way degassing valve can be selected according to the size of the goods.
Here we recommend a more special degassing valve. That is a pasted degassing valve, as the name implied, is a patch. Poking a small hole in your packaging bag or can and then aim at the hold apply the Wojin WJ01p pasted degassing valve.
Pasted degassing valve is a functional packaging component. When a certain pressure has reached in the container, the gas can push open the degassing valve plate from the inside and then be discharged. When the inside pressure in the container is less than the pressure that push the disc open, the valve close automatically. What’s more, only when the inside pressure had been higher than that outside the container, the valve will open, vice versa. The outside air and vapor can’t enter into the container.
Compared with WJ1901 and WJ1902, pasted degassing valve only need to poke holds by human hand and glue the patch. It has no use for valve pressing machine and it is easy to operate and understand.
Because it is easy to operate and need not to be heat-sealed, it is used on all large packaging bag as well as plastic can and iron tank. A wide range of products, such as pickle jars are now using Wojin pasted degassing valve.