One way degassing valve affects the coffee beans

04 Jun 2018

Many customers asked, why did the coffee packaging bag that we bought are broken? The quality seems to be ok but why do the bag inflate after a period of time. Shunde Wojin one way degassing valve can perfectly solve the problems. In fact, people have ignored a factor that is the coffee itself. When roasted, coffee beans or coffee powders produce a gas called carbon dioxide, which is usually used in sodas, and a lot of carbon dioxide is sealed and explodes like a shaken soda. Therefore the packaging bag burst.

Another asked, why did my coffee beans decay for no reasons? Why is that? What is the solution?

Today, Wojin plastic production factory tells what is known about the reasons of the decay of coffee beans.

1. Oxidation. Most aromatic compounds produced by coffee roasting are unstable. When exposed to air, it will be oxidized to produce, some impurities, especially protein and oils, even likely to produce stale taste. Some expired coffee beans smell musty, accompanied by a foul smell of rotting, mostly for this reason.

2. Volatilization. After baking, coffee produces the aroma that is inherently volatile and releases the carbon dioxide which takes away a lot aroma. Just like the sweet fragrance of caramel, flowers and plants, it will disappear quickly.

3. Hydrolysis. Excessive air humidity will make the coffee beans damp and internal material is extracted advance, which causes the hydrolysis occurred, thus some aromatic substances will be transformed and disappeared.

4. Maillard reaction. When the coffee is stored at room temperature, the maillard reaction occurs and the coffee’s complex chemical components interact to slowly degrade or aggregate to produce a lot of mixed flavors. Low temperature storage can inhibit the process of this reaction to some extent.

In fact, in many coffee shops, the coffee beans always have been using the kraft paper, wrapped with aluminum foil, with one way degassing valve, which is designed for coffee international packaging. The holes on the package are the vents of the one way degassing valve.

Installing one way degassing valve on the kraft paper bag or aluminum foil bag can discharge the carbon dioxide released by the baked coffee. The gas can be discharged out of the bag through the mini degassing valve, which also has a protective effect, so the customers don’t have to worry about the gas entering into the bag. The exhaust valve prevents the outside air from entering in and keeps the coffee beans from oxidation so that they don’t smell rancid.

Customers can smell the aroma of coffee beans/ coffee powder through the one way degassing valve. In order to prevent the powder leakage, Wojin has researched and developed a degassing with filter. The thin filter can keep the powder from leakage and is suitable for the storage of coffee powder, which has the same effect with the degassing valve without filter.

Now let’s talk about how this mini one way degassing valve exhaust the gas and prevents reflux.

First, as we known, the mini one way degassing valve is made of valve body and the silicone sheet. In the market today, many degassing valves are two way exhausting, which connect the outside world and don’ have the function of oxygen and humidity. In order to save the cost and time of production, many fraudulent sellers cheat on workmanship and materials in the production process of one way degassing valve, which causes a lot of problems, such as silicon oil volatile, silicon sheet small deformation. These problems will cause gap between body and silicon sheet resulting in the inside of the package has the direct connection with the outside world.

If the low quality one way degassing valve were installed on the packaging bag, the quality of fermented feed, coffee beans and coffee powder would be greatly reduced in the process of storage. Therefore, we suggest that do not covet the cheap exhaust valve and it’s best to have good reputation in the degassing valve production manufacturers choose quality of one way degassing valve. For example, Wojin, such a manufacturer with good reputation, not only has high visibility but also produces the degassing valve that is recognized better quality.

Tag: one way degassing valve

Originally published 04 Jun 2018, updated 04 Jun 2018.


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