One way degassing valve or often called as the freshness valve or the aroma valve or the coffee valve are used to allow pressure to be released from air tight package while preventing air from getting back into the package. Air especially oxygen (O2) can have the negative effect on the packed contents and its freshness. It has 3 parts, the valve body, filter and the rubber disc. Valve body attaches to the air tight package and supports the rubber disc and filter. Filter prevents small particles from clogging the one way valve while the rubber disc adheres or seals to the valve body via a layer of oil and creates an oxygen proof seal.
One way degassing valve is used in packaging of various food products. Especially in bulk transportation via ship or cargo planes, it has been proved to be very efficient in maintaining the quality and freshness. The degasser is also used in HPLC, for the removal of gases from the mobile phase. However, it is most commonly used in the packaging of the fresh roasted coffee. Fresh roasted coffee emits large amount of CO2 for several days after roasting it. At this time, the removal of CO2 is very important to maintain the taste and freshness of coffee. For this, it proves to be very essential and useful applications .The coffee after processing with the one way degassing valve is then packed in the bags or pouches. Coffee bags are made up of plastic which can be sealed with a zipper for confirming the quality of the product. Easy opening and closing of the bags are facilitated by this zipper profile. They are used to store food items as they secure the nutrients of the food and their by protecting it from environment. Zipper storage bags are versatile, easy to use and low in cost. They can also be used for other types of products such as tools, stationary items and gardening equipment.
Zipper bags are normally thicker and more durable than other types of plastic bags. This kind of bags are available in every size from vary small to a quite long. The main advantage of zipper profile is that it can b used again and again. This is one of the reasons why they are so popular in even household works. But one of the disadvantages is that they become worthless when the zipper doesn't work.