What is the coffee exhaust valve

10 Jan 2020

Q1: What is the coffee exhaust valve?

A1: The coffee exhaust valve is one of the packaging accessories on the coffee bag, which is also called one-way exhaust valve. The one-way exhaust valve is usually used on coffee bag and fermented feed bag. As the coffee will produce a high volume of carbon dioxide during the roast process, the quality of coffee will be effect and the bag will be broken if we don’t use the one-way valve to let the gas run out for a long time period. The main aim is to keep the product fresh.

Q2: What is the working principle of one-way valve?

A2: When the gas generated by the product sealed in the bag makes the inside of the bag reach to a certain pressure, the gas can be pushed from the inside to the outside to open the exhaust valve sheet, and the excess gas is discharged outward. When the pressure in the bag reduced to the level which is not enough to open the valve, the valve will close automatically. Meanwhile, the valve will automatically open only when the pressure inside the bag is higher than the pressure outside the bag, otherwise, it will not open, and the air outside will not enter to the bag.

Q3: What is the difference between an exhaust valve with filter net or not?

A3: The difference between an exhaust valve with or without a filter net is the item that it used to store. The one with filter net is suitable for coffee bean, coffee powder, feed, kimchi and flour, which refers to granular and powder product. The one without filter net is suitable for coffee bean, cat food and dog food, which refers to granular product.

Tag: coffee valve

Originally published 10 Jan 2020, updated 10 Jan 2020.


How do you keep coffee fresh after opening

10 Jul 2020

Remember to seal the packaging bag after taking some coffee out, so the one-way degassing valve would finish its job to keep the freshness of product.

Does ground coffee need to breathe

03 Jul 2020

Roasted coffee cannot be put directly into a sealed package, because the coffee need to "breathe", that is, the carbon dioxide gas will be released.

Why do coffee packs have an aroma hole if it is recommended to store coffee in an air tight container

26 Jun 2020

This is a hole punched before installing the degassing valve, which purpose is to discharge the CO2 released and avoid the oxidation of coffee.