What Changes Occur in Coffee Bean Flavor During the Aging Period? Can Single-Origin Coffee Beans Be Aged in Completely Sealed Containers?

FrontStreet Coffee - Introduction to Coffee Bean Degassing

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1. What is Bean Degassing

Bean degassing refers to the process where roasted beans, stored in sealed coffee bean bags after baking, release carbon dioxide and other gases produced during the roasting process. Through several days of resting, various substances inside the coffee beans stabilize.

The coffee bean bags we use for storing coffee have one-way degassing valves. The function of the one-way degassing valve is to allow gas to escape from the bean bag while preventing air from outside entering the bag. The advantage of this is that it can avoid contact with air before opening, and basically all bean bags are light-proof.

At this point, some people might ask: Why are beans from some coffee shops stored in transparent jars? This is because they have already gone through the degassing period. At this time, baristas don't want the coffee beans to continue releasing gas, because whether during the degassing period or the optimal tasting period, coffee beans are always releasing their aromatic substances into the air. Unfortunately, baristas don't have magic powers and cannot use vacuum sealing, so they can only use sealed jars for storage, minimizing the loss of aromatic substances as much as possible. Additionally, the location of these sealed jars must be light-proof.

Some roasters will conduct cupping immediately after roasting. In this case, there's no need for degassing. They might cup right after roasting or perhaps wait one day. Because cupping methods are special, this approach presents both the good and bad aspects of the coffee. Therefore, as something like a "magic mirror," this method doesn't really care whether the beans have been degassed or not.

Other extraction methods are quite different. Pour-over, siphon, French press, and AeroPress all place great importance on bean degassing.

Among these, the extraction method most affected by whether beans are degassed or not is the espresso machine. Fresher coffee beans are harder to extract because there's too much carbon dioxide, which significantly hinders water's extraction of coffee grounds.

Coffee that hasn't been degassed immediately after roasting tastes a bit more stimulating compared to degassed beans, with less pronounced flavors and overall less roundness.

Alright, as mentioned earlier, coffee beans are always releasing their aromatic substances into the air, so there's a time limit for tasting coffee beans. Based on my personal understanding, the tasting period for single-origin coffee is 20-30 days, while for espresso coffee, it's 30 days.

So how long does the coffee degassing period take?

Single-origin light roast degassing time: 3-4 days

Single-origin dark roast degassing time: 4-7 days

Espresso coffee degassing time: 15-21 days

Key Point:

Overall, degassing mainly targets espresso extraction and doesn't have as many requirements for pour-over - just 3-4 days is sufficient.

In Summary:

FrontStreet Coffee is a coffee research establishment that enjoys sharing coffee knowledge with everyone. We share without reservation only to help more friends fall in love with coffee. Additionally, we hold low-discount coffee activities three times every month. This is because FrontStreet Coffee wants to let more friends enjoy the best coffee at the lowest prices, which has been FrontStreet Coffee's principle for the past 6 years!

Important Notice :

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