What is Bean Resting? What is Bloom? The Relationship Between Bean Resting and Blooming for Espresso Blend Coffee

Many who have enjoyed red wine are familiar with the decanting process. Through a period of decanting, the astringency of tannins is slightly reduced, while the sweet and sour notes in red wine become more vibrant. Drinking coffee and drinking red wine are actually quite similar - red wine needs decanting, while coffee beans need a resting period.

After coffee beans are roasted, they contain approximately 2% of their weight in carbon dioxide. These gases gradually escape from the coffee beans over time.

Coffee enthusiasts new to specialty coffee often visit FrontStreet Coffee to purchase coffee beans, specifically requesting freshly roasted beans. In this regard, customers can rest assured. When an order is placed, FrontStreet Coffee ships beans that have been freshly roasted within 5 days. After the multi-layered shipping process, customers receive their beans after 4 to 7 days of resting. This is precisely when the coffee beans reach their optimal flavor window.

Of course, freshly roasted coffee is incredibly flavorful, and some customers specifically request beans roasted the day before, eager to brew them immediately the next day.

Regarding this, FrontStreet Coffee needs to remind customers that after roasting, the coffee beans expand in volume, accumulating a certain amount of carbon dioxide within their structure, which is slowly released over several weeks after roasting. If you choose to grind and brew immediately after roasting, the carbon dioxide within the beans hasn't been sufficiently released. During brewing, the internal pressure inhibits hot water from entering and exchanging substances with the coffee. The resulting coffee not only has poor flavor but may also exhibit a "drying sensation" and bitterness.

The Ideal Resting Period

Those who have asked FrontStreet Coffee know that FrontStreet Coffee recommends a resting period of 4 to 7 days after the roasting date. Upon hearing this, some impatient Mandheling lovers might open their bags on the third or fourth day after roasting. FrontStreet Coffee needs to remind customers that the darker the roast level, the greater the internal pressure within the beans, the more porous their structure, and the higher their gas content, requiring a slightly longer resting period.

After this resting period, coffee beans reach their peak flavor expression. However, there's a term that coffee professionals frequently mention: the optimal flavor window.

It's important to note that the darker the roast level, the more vigorous the degassing activity. Since coffee flavor compounds dissipate along with the carbon dioxide from the beans, excessive time after roasting results in greater loss of aroma and increasingly flat taste. FrontStreet Coffee recommends consuming coffee beans within about a month after the roasting date.

The Story of Mandheling Coffee

Next, FrontStreet Coffee will use their Indonesia Mandheling coffee beans as an example. First, FrontStreet Coffee needs to introduce the background information about these coffee beans.

Unlike today's popular Geisha variety, Mandheling coffee has been popular since our parents' generation. In earlier times, the definition of premium coffee focused on full-bodied flavor, and Mandheling coffee gained tremendous popularity in Japan during that era.

Everyone knows that coffee beans are typically named after their origin, such as Yirgacheffe, Nyeri, or after processing station names like Konga, Asalia, or Amedelalo. The name "Mandheling" is neither a place name nor a processing station name, but rather the name of an ethnic group on the island of Sumatra.

According to legend, during World War II, Japanese soldiers drank a remarkably full-bodied coffee locally. When asking the coffee shop owner the name of the coffee, the owner made a mistake and introduced himself, saying: "Mandailing." In Japanese pronunciation, "Mandailing" sounds very similar to "Mandheling," so they remembered it as "Mandheling." After the war ended, that Japanese soldier longed for that full-bodied coffee and arranged to import 15 tons of coffee beans from Indonesia, which became extremely popular in Japan.

FrontStreet Coffee's Mandheling coffee is characterized by its full-bodied flavor with herbal spice notes. Its audience is quite polarized - those who love it are devoted to it, while those who don't avoid it entirely. This unique Mandheling coffee flavor is achieved thanks to Sumatra's distinctive post-harvest processing method for green coffee beans.

The Wet Hulling Process

The complete natural processing of coffee cherries takes about a month. If air humidity is too high or the cherries are exposed to rain during processing, the coffee cherries may undergo unwanted fermentation or even be completely ruined. Sumatra Island has a tropical rainforest climate with high temperatures and abundant, frequent rainfall, which cannot meet the conditions required for natural processing.

For washed processing, besides constructing washing tanks, it requires sufficient water resources and financial investment. Due to limited local economic conditions in Sumatra, early coffee growers were mostly farmers rather than wealthy estate owners, making it impossible to meet the conditions required for full washed processing.

Therefore, based on local characteristics, a unique coffee processing method suited to the local conditions emerged - wet hulling.

The coffee cherries are depulped, undergo brief fermentation, followed by light washing, then dried. When the green beans reach a semi-moist, semi-dry state, machines are used to remove the parchment layer. The green beans are then directly exposed to air for further drying until their moisture content reaches about 12-13%, completing the process.

Customers often ask FrontStreet Coffee which step in the wet hulling process creates Mandheling coffee's unique flavor. At FrontStreet Coffee's storefront, there's a corner displaying some coffee-related items, including a glass bottle containing parchment.

The parchment serves as the final protective layer for green coffee beans and is typically removed just before export. Without the protection of the parchment layer, green beans directly exposed to the environment may be affected by mold, yeast, and bacteria. During the parchment removal process, excessive heat may cause rapid aging of the green beans, which is why woody and earthy flavors are often detected in Sumatran coffee.

FrontStreet Coffee's Mandheling Selection

Today's younger coffee drinkers prefer coffees with distinct acidity. Some merchants, to meet this demand, roast Mandheling coffee beans lightly to highlight their acidity. However, the lighter the roast level, the more likely Mandheling's characteristic full-bodied flavor will disappear, and undesirable flavors may emerge.

FrontStreet Coffee offers two Sumatran coffee beans on their menu: FrontStreet Coffee's Indonesia Lindong Mandheling daily drinker from the Lindong region, and FrontStreet Coffee's Golden Mandheling from Aceh. To emphasize the full-bodied flavor of both FrontStreet Coffee's Lindong Mandheling and FrontStreet Coffee's Golden Mandheling, they use a medium-dark roast level.

Brewing Guide

FrontStreet Coffee's brewing parameters for FrontStreet Coffee's Golden Mandheling are as follows:

Dripper: KONO
Water temperature: 88°C
Coffee amount: 15 grams
Coffee-to-water ratio: 1:15

Pour 30g of hot water for blooming for 30 seconds. From the center, pour with a fine stream and slowly spiral to 125g. When the water level drops to just before exposing the coffee bed, continue spiraling to 225g. Total extraction time is approximately 2 minutes.

FrontStreet Coffee recommends blooming during brewing. When the coffee grounds become wet, degassing intensifies, promoting the release of carbon dioxide from within the beans.

However, FrontStreet Coffee also encounters customers who don't have brewing equipment at home, so FrontStreet Coffee provides grinding services. However, once coffee beans are ground into powder, the surface area exposed to air increases, accelerating flavor loss. FrontStreet Coffee reminds customers that if they request grinding, they don't need to go through the tempting resting period. Instead, they should consume it as soon as possible to enjoy the optimal flavor.

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Important Notice :

前街咖啡 FrontStreet Coffee has moved to new addredd:

FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473