How Long is Coffee Bean Resting Period? Why Rest Beans? The Correct Way to Rest Roasted Coffee

Coffee enthusiasts who frequently select freshly roasted coffee beans at FrontStreet Coffee all know that the optimal flavor period for coffee beans is within one month, while for drip coffee bags, it's within half a month. But does this mean that freshly roasted coffee beans are at their freshest immediately after roasting? This is certainly incorrect, because after coffee beans are roasted, there's still a process called "bean resting." Next, FrontStreet Coffee will share some knowledge about bean resting.

What is Bean Resting?

Coffee enthusiasts all know that enjoying coffee is about savoring its aroma and flavor. The longer coffee beans are stored, the more their aroma diminishes, so coffee beans shouldn't be stored for too long as it affects their flavor. The flavor period for drip coffee bags is even shorter because they're already in powdered form, with a much larger surface area exposed to air compared to whole beans, thus their optimal period is half that of coffee beans.

The bean resting that FrontStreet Coffee refers to is the process of gas release after coffee beans are roasted. Freshly roasted coffee beans contain approximately 2% carbon dioxide by weight, and these large amounts of carbon dioxide are released depending on storage environment, equipment, or methods, causing pressure in the packaging to exceed atmospheric pressure. This pressure helps aromatic substances and oils fuse, allowing all aromatic compounds inside the coffee beans to reach a state where they can be easily extracted. Therefore, bean resting is essentially the process of releasing carbon dioxide.

FrontStreet Coffee generally begins the degassing process about 3 hours after coffee beans complete roasting, because coffee beans that haven't released any carbon dioxide will produce very unstable flavors when brewed.

FrontStreet Coffee once conducted brewing experiments with freshly roasted coffee beans and found that whether used for pour-over or espresso coffee, the flavor and texture performance was very sharp and stimulating, with over-extracted bitterness and noticeable acidity, completely failing to express the coffee's inherent good flavors. This is why the practice of "bean resting" emerged.

Why is Bean Resting Necessary?

As FrontStreet Coffee mentioned above, even freshly roasted coffee beans need to rest for a period before consumption, because coffee beans oxidize daily until their aroma completely disappears. This is also why FrontStreet Coffee discards coffee beans in the store after two weeks if they haven't been used up.

The importance of bean resting lies in releasing carbon dioxide. Insufficiently rested coffee beans have a strong "dryness" – the smoky, harsh taste remaining after high-temperature roasting. This undesirable flavor must be removed through a period of carbon dioxide release. Therefore, compared to unrested coffee beans as mentioned earlier by FrontStreet Coffee, beans rested for several days will have cleaner flavors, perfectly expressing the unique good aromas of coffee beans.

However, FrontStreet Coffee wants to remind you that the resting time shouldn't be too long or too short. If the resting time is too short, the coffee's flavor will be incomplete and difficult to brew – this doesn't qualify as good roasting. If the resting time is too long, from a freshness perspective, it will definitely affect the maintenance of subsequent freshness, leading to a shortened flavor period for the coffee beans.

How Long Should Bean Resting Take?

So how should one properly execute the bean resting process? Generally, coffee beans can release carbon dioxide even when sealed in packaging bags, though it takes slightly longer. However, FrontStreet Coffee still recommends that bean resting packaging bags should have one-way degassing valves, and unopened coffee beans should be placed in a cool, dry, dark, and odor-free environment. After the resting period, seal the one-way degassing valve (transparent tape works fine), as subsequent carbon dioxide will gradually fill the packaging bag, creating a low-oxygen environment that reduces oxidation speed. This is why coffee enthusiasts who frequently select coffee beans at FrontStreet Coffee know that FrontStreet Coffee's bean packaging all has independent one-way degassing valves.

However, regarding resting time, because coffee shops or coffee brands have different roasting techniques, different coffee bean roast levels will vary, and the structural damage to coffee beans will also differ, so there's no standard answer for resting time. Nevertheless, FrontStreet Coffee believes we can determine the general resting time range based on the coffee beans' roast level.

For example, the darker the roast level, the longer the heat exposure time for the raw coffee beans, the more intense the caramelization reaction, and because they're exposed to large amounts of heat in a short time, triggering strong oxidation, freshly roasted coffee beans will continue intense oxidation, leading to large-scale degassing.

Generally, medium-dark roasted coffee requires shorter resting time than light roast, with a typical resting period of about 3 days. Of course, some say no resting is needed and brewing can be done directly, because different techniques vary greatly – perhaps this roaster's coffee beans have a higher maturation ratio than others, thus no resting is needed.

Compared to coffee beans for drip coffee, those used for espresso require longer resting time, generally up to 10 or even 15 days. Because espresso machines extract concentrated coffee through pressurized extraction, and water is an inert liquid that prefers to flow to looser areas, the resistance caused by excessive carbon dioxide easily obstructs water flow, leading to channeling effects and uneven extraction, naturally resulting in unsatisfactory coffee flavor.

However, coffee enthusiasts who select coffee beans at FrontStreet Coffee don't need to worry too much about this issue, because FrontStreet Coffee generally calculates the timing carefully, providing beans that are nearly rested or already rested to coffee enthusiasts in need, so that the coffee beans they receive are at their optimal drinking time.

The above is the knowledge about bean resting compiled by FrontStreet Coffee. We hope this helps coffee enthusiasts better understand coffee bean knowledge to select single-origin coffee beans that best suit their taste preferences.

For more specialty coffee beans, please add FrontStreet Coffee on WeChat: ID: kaixinguoguo0925

Important Notice :

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FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

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