03 Apr 2020
Have you noticed that some coffee bags on the display shelf have a small button-shaped accessory when you walk into a café? This accessory is named as one way degassing valve, which is usually used on fermented food and coffee packaging. The degassing valve usually made with HDPE material, and it aims to regularly allow internal gas to escape from the small degassing valve on the package when the internal pressure exceeds a (smaller) value. That is, the air cannot enter the packaging bag from the outside (since it is a ONE-WAY valve), thus creating a sealed exhaust effect to keep the product fresh.
The one-way degassing valve was initially designed for the coffee industry. Because the coffee bean roasted freshly will naturally produce large amount of gas, which mainly contains CO2. Although the amount of CO2 will be different due to the type of coffee, those dark roasted coffee bean could produce more than 5 liters of gas per pound of beans. By choosing the WOJIN one-way exhaust valve WJ1901 with a filter will achieve a well exhaust effect and then keep the coffee fresh.
Currently there are two types of degassing valve on the marketplace, one is the built-in exhaust valve, and the other is external degassing valve.
The built-in exhaust valve is installed in the bag, and it needs to be installed with hot pressing by using a pressure valve machine. The built-in exhaust valve includes both with-filter and without-filter. Usually, the with-filter one has a wider range of applications. It can be used on the packaging bag for coffee beans/powder, fodder for pigs and horses, cat food, dog food, flour, ready-mixed baking powder and any other solid or powdery items. In contrast, the external degassing valve can only be used in less range of functions. It can only be installed on the packaging bags for granular products such as coffee beans and cat/dog food. WOJIN introduced built-in degassing valve WJ1901 (with-filter) and WJ1902 (without filter) in order to satisfy our customers` needs. To let our one-way degassing valve helps to retain the aroma of your coffee.
When we talk about the external degassing valve, it is usually a patch type degassing valve. The user only needs to poke a small hole on the surface of the packaging bag and directly stick the degassing valve on the hole. This simple installation method helps to simply the process, which is different from installing a traditional degassing valve. The external degassing valve is convenient, efficient, and will stick firmly, which have the same effect as the built-in degassing valve. The external degassing valve introduced by WOJIN includes WJ01P and WJ02P, both can be used for soft food packaging, composite packaging bags or films, and can containers anytime and anywhere. People are able to select the most suitable degassing valve according their needs.
Originally published 03 Apr 2020, updated 03 Apr 2020.
Take the coffee bean as an example, the steps from plant, pick, roast, are all connected , without the one-way valve usually make the coffee less fresh.02 Aug 2020
The external oxygen will be stopped from entering the bag, so that the package is in a working state, thereby protecting the freshness of the food in the bag.25 Jul 2020
When storing the coffee, we need to avoid light and heat, and keep it in a dry environment, we then need to use coffee packaging bags with coffee valves.