How do coffee bags work?

Can roasted coffee beans be brewed immediately? Yes, but not necessarily tasty. Freshly roasted coffee beans will have a bean raising period, which is to release carbon dioxide and achieve the best flavor period of coffee. So how do we store coffee? To store coffee beans, we think of using coffee bags for the first time, but have you carefully observed the packaging bags of coffee beans? Ever notice a white or clear valve on the back or inside of the coffee bag? Or did you see it and didn't care? Don't think that this valve is dispensable when you see that the valve is small. In fact, the small beat valve is the secret of the "life or death" of coffee beans.

This valve is what we call the "coffee exhaust valve", and it's called a one-way exhaust valve. The one-way vent valve plays a vital role in helping your fresh coffee stay fresh longer. The one-way vent valve inside the coffee bean bag is a bag accessory that prevents backflow of air. A brief overview of the one-way exhaust valve valve has two functions, one is to discharge the gas in the bag, and the other is to isolate the air outside the packaging bag from entering. Next, the Wo intake valve will introduce these two functions and how it works.

1. Exhaust

Green coffee beans contain acids, proteins, esters, carbohydrates, water and caffeine. After green coffee beans are roasted at high temperature, carbon dioxide is produced through a series of chemical reactions such as the Maillard reaction. Generally speaking, the carbon dioxide and other volatile gases released by roasted coffee beans account for 2% of the weight of the whole coffee beans. And 2% of the gas is slowly released from the fiber structure of the beans, and the release time will depend on the roasting method. Because coffee beans emit carbon dioxide by themselves, we will see roasted coffee beans in a sealed bag that will bulge over time. This is the so-called "inflated bag". With the one-way exhaust valve, it will help to remove these inert gases from the bag in time, so that these gases will not oxidize the coffee beans and maintain a good fresh state for the coffee beans.

2, isolate the air

How to isolate the air while exhausting it? The one-way valve is different from the ordinary air valve. If a common air valve is used, while the gas in the coffee packaging bag is discharged, it will also allow the air outside the packaging belt to flow into the bag, which will destroy the sealing performance of the packaging bag and cause the coffee to continue to oxidize. Oxidation of coffee beans will cause aroma volatilization and composition deterioration. The one-way exhaust valve does not, it exhausts the carbon dioxide in the bag in time, and does not allow the outside air to enter the bag. So, how does it manage to not allow outside air to enter the belt? The Wo intake valve tells you its working principle: when the air pressure in the bag reaches a certain threshold, the valve of the one-way exhaust valve opens to release the gas in the bag; until the air pressure drops below the threshold of the one-way valve. The valve of the one-way valve is closed, and the packaging bag returns to a sealed state.

Therefore, we concluded that the unidirectionality of the coffee exhaust valve is its most basic requirement and also the most advanced requirement. When the coffee beans are roasted more deeply, the exhaust effect will be stronger, and the carbon dioxide will be released sooner.