Why Do Freshly Roasted Coffee Beans Need Degassing? How to Brew Under-Rested Pour-Over Coffee for Better Taste?

Whenever FrontStreet Coffee's delivery arrives, some coffee enthusiasts can't wait to unbox the beans and brew a cup to satisfy their cravings! But then they check the roast date... Oh no, these were just roasted in the past couple of days... The beans haven't rested yet... But I really want to drink them right now! What should I do!!!

Why do fresh coffee beans need resting?

FrontStreet Coffee knows that many eager coffee lovers, upon receiving coffee beans roasted within the past couple of days, immediately brew a cup only to discover that the coffee lacks distinctive flavors and instead has a heated sensation (dryness), leaving a feeling similar to smoke stuck in the throat. However, after letting it rest for two to three days, they find the coffee becomes much rounder, with flavors becoming more pronounced.

This is because coffee beans generate large amounts of carbon dioxide during the roasting process, and these carbon dioxide molecules remain highly active in the initial period after roasting completes. During subsequent brewing, the presence of carbon dioxide impedes water from penetrating these fiber structures to dissolve the flavor compounds in the coffee. The higher the carbon dioxide content, the stronger this blocking effect becomes, which means it hinders the coffee flavors from properly infusing into the water, resulting in uneven extraction.

The primary purpose of the "blooming" step during brewing is to release carbon dioxide, reducing the likelihood of uneven extraction caused by continuous changes in water flow channels through the coffee grounds due to excessive carbon dioxide release. FrontStreet Coffee recommends a coffee blooming time of 30 seconds—this is the suggested blooming time for properly rested coffee beans. However, very fresh coffee beans contain more carbon dioxide than properly rested beans, so within the same timeframe, very fresh coffee beans cannot effectively release their carbon dioxide.

The heated sensation often occurs because coffee beans retain residual smoky flavors after high-temperature roasting. These smoky flavors require time to dissipate along with the carbon dioxide release. Therefore, compared to freshly roasted coffee beans, those sealed and left to rest for several days will have a cleaner taste and more prominent flavors.

How to rest freshly roasted coffee beans?

Quite simple! No need to open the package or refrigerate—just keep it in the original packaging in a cool, dry place. FrontStreet Coffee's bean packaging features a one-way degassing valve, which allows carbon dioxide to "push open" the valve along with the dryness sensation when it reaches a certain pressure inside the package. Since it only opens one-way, you don't need to worry about external air and moisture entering the bag.

Using the coffee beans sold by FrontStreet Coffee as an example, each package is marked with a roast date. Generally, light to medium roast pour-over coffee beans need about 4-7 days of resting, medium to dark roast pour-over coffee beans need about 7 days, while espresso beans are recommended to rest for about 10 days.

Impatient! Want to drink it right away...

Is there a way to reduce the dryness of fresh coffee beans and bring out their flavors?

Method 1: Let the ground coffee rest for 30 seconds to 1 minute

When coffee beans are ground into particles, carbon dioxide releases more quickly. So if you're truly eager to brew a cup of pour-over coffee, you can let the ground coffee rest for 30 seconds to 1 minute after grinding.

However! While this approach can release most of the carbon dioxide, the coffee's aroma will also escape along with the carbon dioxide release! Although this method can reduce the dryness of fresh coffee beans, the aroma of the coffee might be less noticeable.

Method 2: Extend the blooming time

Blooming has an exhaust effect because when water comes into contact with coffee grounds, the soluble and volatile substances in the grounds accelerate their movement when heated, thereby speeding up the release of carbon dioxide.

As mentioned above, FrontStreet Coffee normally recommends a blooming time of 30 seconds for properly rested coffee beans. If the coffee beans haven't rested sufficiently and still contain high amounts of carbon dioxide, we can appropriately extend the blooming time by 10-20 seconds (meaning 40-50 seconds of blooming), giving carbon dioxide more time to release. While this method of brewing fresh coffee beans can extract their flavors, there will still be some degree of dryness.

Final Thoughts

Although very fresh coffee beans can be brewed using the two methods above, the resulting coffee will still have shortcomings. Therefore, FrontStreet Coffee still recommends that everyone wait patiently, allowing the coffee beans to rest and then present their best selves~

Important Notice :

前街咖啡 FrontStreet Coffee has moved to new addredd:

FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473