What Grade is Wet-Hulled Mandheling Coffee? How Are Wet-Hulling and Semi-Washed Drying Related?

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As the darkest roasted single-origin coffee in FrontStreet Coffee's bean selection, Mandheling coffee possesses rich roasted aromas, a solid and mellow mouthfeel, with low acidity. When deep roasted, we can experience both its lingering bitterness and enjoy its elegant sweetness. Through both smell and taste, we can simultaneously perceive its unique earthy fragrance, which is truly intriguing.

At this point, some might ask: among all medium-dark roasted coffee beans, why does only Mandheling have this unique flavor?

As we know, Mandheling originates from Sumatra Island, Indonesia. The biggest difference from many coffee-producing regions is Indonesia's variable weather—humid and rainy, with humidity levels between 70-90% year-round. Sometimes it's sunny in the morning and rainy in the afternoon, with typhoons appearing unexpectedly. Annual rainfall even exceeds 2000mm. Under such harsh climate conditions, completely drying parchment beans to the specified moisture content is extremely difficult and time-consuming. Since Indonesia is a major coffee-producing country focused on mass production, people devised a unique semi-washed method to shorten coffee processing time and sell beans quickly: the Wet Hulling method.

Wet Hulling, known as "Giling Basah" in Indonesian, has existed and been practiced in coffee production for many years, just like washed, natural, and honey processing methods. Currently, wet-hulled coffee is still primarily produced in Indonesia, with the northern regions of Sumatra and Sulawesi being the main production areas.

Initially, this region also mainly used natural processing, but quality was unstable, so they switched to a semi-dry method similar to Brazil's. However, unlike Brazil's arid climate, they couldn't dry the sticky parchment beans outdoors for several days after removing the coffee fruit pulp—doing so in Indonesia's hot, rainy conditions would cause them to mold directly. Therefore, they would only dry them outdoors for one to two days.

When the moisture content of parchment beans drops to 30-50%, they are purchased by brokers. At this point, the mucilage layer hasn't solidified yet, and the beans are still semi-hard and semi-soft, but they need to be quickly brought to processing plants and hulled with specialized machines to prevent over-fermentation and sour odors.

Due to the greater difficulty of hulling in wet hulling, machines need to use more friction to tear away the parchment layer tightly adhered to the green beans. At this stage, white or green viscous liquid typically flows out. Due to long-term immersion in this liquid and the humid environment, the green beans become soft, pale and swollen, forming a gray-green color. Stirred by friction, the green beans are also more easily crushed or bruised, especially at both ends, forming small notches shaped like goat hooves—this is why Sumatra has a higher proportion of "goat hoof beans."

It's important to know that coffee beans have four protective layers: pulp, mucilage, parchment, and silver skin. Wet hulling removes the third and fourth protective layers midway. This means the coffee beans directly expose their "inner beans" to sunbathe.

After the parchment beans are hulled by machines, they continue drying until the moisture content reaches approximately 12-15%, at which point they can be bagged. Finally, these coffee beans are sent for machine selection to remove various impurities, then classified by particle size, with G1 being the highest grade. FrontStreet Coffee's Mandheling uses G1 grade beans processed via wet hulling, which can be purchased directly from FrontStreet Coffee's Taobao store or Tmall flagship store.

The "naked beans" without parchment dry very quickly and are directly exposed to sunlight and humidity, allowing various microorganisms to grow, giving Indonesian coffee its unique woody, spicy, and herbal notes—what we call "terroir flavor."

From this, we can understand that Mandheling's unique herbal and woody flavors result from the local high humidity, which forced the post-processing to be divided into three stages for drying the mucilage layer. This is also a rare processing method worldwide that accidentally created Mandheling's special low-acidity, thick-bodied, and earthy flavor profile.

Customers might ask FrontStreet Coffee: which Mandheling should I choose? If you're a coffee newcomer just beginning to explore different regional flavors, FrontStreet Coffee recommends starting with our cost-effective Lindong Mandheling as a daily drink. This way, you can understand the flavor characteristics of several major producing regions before choosing your preferred type. But if you're already a coffee connoisseur, FrontStreet Coffee believes PWN Golden Mandheling is an excellent choice.

Brewing Methods

Mandheling presents rich roasted coffee aromas and a solid mouthfeel, suitable for various brewing extraction methods such as pour-over, siphon, French press, AeroPress, moka pot... FrontStreet Coffee's favorite way is tasting Golden Mandheling's rich flavors as a pour-over black coffee.

FrontStreet Coffee prefers using KONO drippers to extract full-bodied coffee beans. The KONO dripper has short ribs only in the middle and lower sections, with the upper part being a smooth curved surface. When we wet the dripper, it fits tightly with the filter paper, restricting coffee exhaust during extraction. This increases the residence time of hot water in the dripper, enhancing coffee extraction rate and concentration, resulting in richer, fuller coffee flavors. KONO drippers are also suitable for other full-bodied beans like Brazil Queen Estate coffee.

Brewing Parameters

FrontStreet Coffee typically chooses 15g of coffee grounds, with the amount based on the dripper's design specifications. FrontStreet Coffee's dripper is suitable for 1-2 servings, between 15-20g of grounds, as excessive amounts can affect extraction. Regarding coffee-to-water ratio, 1:15 is most commonly used, with ratios between 1:13-1:17 being acceptable. FrontStreet Coffee believes everyone's taste is different—1:13 might be too strong for some, while 1:17 might be too weak, so we take the middle value of 1:15.

Brewing parameters: KONO dripper, 87°C water temperature, 1:15 coffee-to-water ratio, China No. 20 standard screen-sieved 70% grind size, 15g coffee grounds, three-stage extraction.

First wet the dripper so the filter paper fits tightly with it, then pour in the ground coffee, trying to level the coffee bed as much as possible. Pour 30g of 87°C hot water from the center to start the 30-second bloom, during which you'll see the dark-roasted Mandheling form a high dome. Then begin evenly pouring the second stage until the liquid weight reaches 125g. When the coffee level drops to halfway, start pouring the final 100g. Note to maintain a small, steady water flow throughout to avoid uneven extraction. Once all the coffee liquid has finished dripping, you can remove the dripper, shake the sharing pot to mix the coffee, and begin tasting.

The brewing parameters mentioned by FrontStreet Coffee are based on fresh coffee beans, so fresh roasted coffee is the primary condition here. Coffee beans shipped by FrontStreet Coffee are freshly roasted within 5 days, so when you receive them from logistics, they are just at their optimal flavor period. This is done so that every customer can enjoy coffee with the most complete flavor profile.

Freshly brewed PWN Golden Mandheling clearly has a solid mouthfeel, with intensified cedar, spice, dark chocolate, and roasted hazelnut notes. The finish is clean, with enhanced flavor layers where you can perceive caramel sweetness and aftertaste.

Important Notice :

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