How to Brew Fresh Coffee Beans and Expired Beans? Why Does Pour-Over Coffee Easily Become Over-Extracted?

Sometimes, we get sudden urges to try what coffee tastes like when brewed with freshly roasted or overly aged beans. If we use our regular brewing method for pour-over, we'll likely end up with either under-extracted or over-extracted coffee. Therefore, today FrontStreet Coffee would like to share how to brew fresh and stale beans respectively~~

How to Brew Fresh Coffee Beans?

Roasted beans contain abundant carbon dioxide, which hinders hot water extraction and affects the release of aromatic compounds. Therefore, we use blooming to remove this gas. However, when beans are too fresh, they contain excessive carbon dioxide, and the short 30-second blooming time may not be sufficient to release all of it. So, we might try extending the blooming time to allow more carbon dioxide to escape. Typically, we bloom for 30 seconds, but when brewing fresh beans, we can extend the blooming time by 5-10 seconds, depending on the roast level of the beans. The darker the roast, the longer the time~

In addition, we can slightly increase extraction efficiency. Because extending the blooming can only release a limited amount of carbon dioxide, the remaining gas in the beans will still hinder hot water extraction. Therefore, improving extraction efficiency will also greatly help the brewing process. Taking FrontStreet Coffee's standard light roast extraction protocol as an example: 15g of coffee, 1:15 coffee-to-water ratio, 92°C water temperature, ground at EK43 setting 10, using a V60 dripper. Extraction parameters that can be increased for light roast beans include: water temperature, which can be increased by 1-2°C; grind size, which can be adjusted one setting finer; or extending extraction time by adjusting water flow is also a good option. (Only need to increase one of these!)

Another negative effect of overly fresh coffee beans is that they can have a "roasty" or "dry" sensation! When drinking coffee brewed from these beans, you might experience a feeling similar to being lightly choked by smoke in your throat. In this situation, we can try pre-grinding! This means grinding the coffee beans in advance and letting them sit for a while (1-2 minutes longer than usual). This approach helps release carbon dioxide and reduce the roasty sensation more quickly. Because after grinding, the surface area of coffee powder exposed to air increases, allowing it to release gases more quickly than when in whole bean form. Therefore, by letting pre-ground coffee sit, we can degas and reduce the roasty sensation.

How to Brew Stale Beans?

When coffee beans have been stored for more than two months, carbon dioxide has almost completely dissipated. Besides hindering hot water extraction, carbon dioxide also helps preserve aromatic compounds. So when carbon dioxide is completely lost, not only can hot water extract substances from coffee more effectively, but the coffee's aroma will also dissipate more quickly. The negative situations that easily occur when brewing this type of coffee are: over-extraction and insufficient aroma expression.

The over-extraction situation is easy to resolve - we just need to appropriately reduce extraction efficiency! Because our extraction formulas are all based on parameters customized for beans at their optimal flavor period. Generally, such extraction formulas have relatively high efficiency for beans past their optimal flavor period, making over-extraction likely. When large amounts of carbon dioxide have dissipated, the substances hindering extraction have disappeared, so we no longer need such high efficiency for extraction! Therefore, adjusting to a coarser grind or reducing extraction time are adjustment directions that FrontStreet Coffee recommends~

Since most aromatic compounds in coffee are volatile, when beans are stored for too long, these aromatic substances will also be largely lost. Even with normal extraction rates, brewed coffee will exhibit a bland and thin condition. At this point, we can use another method to remedy the situation: "high concentration, low extraction." Simply put, this means using the original extraction formula but increasing the coffee dose or adjusting the coffee-to-water ratio to increase concentration. When flavors are not prominent, it indicates that the flavor concentration of the coffee is no longer as high as before, so we can enhance flavor expression by increasing concentration~

Specific operations could include: keeping the water amount constant while increasing the coffee dose (changing from 15g coffee with 225ml hot water to 16g coffee with 225ml hot water); or reducing the water amount while keeping the coffee dose constant (changing from 15g coffee with 225ml hot water to 15g coffee with 210ml hot water). But FrontStreet Coffee must remind you that these are only improvement plans that can slightly improve beans lacking flavor; they cannot make stale beans taste as rich as fresh ones. There is absolutely no comparability between the two, and they must not be confused~ After all, coffee is best when freshly roasted~

Important Notice :

前街咖啡 FrontStreet Coffee has moved to new addredd:

FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473