Where does Sumatra Mandheling coffee come from and how is it processed?

Sumatra Mandheling coffee comes from the Indonesian island of Sumatra, where coffee cultivation is centered in the highlands around Lake Toba and Aceh. Despite the name, Mandheling refers to a people and a trading tradition rather than a botanical variety; the beans are typically Typica, Catimor, or other Arabica types grown at elevations of 1,000 to 1,500 meters in volcanic soil.

The wet-hulling process, known locally as giling basah, sets Sumatran coffee apart from washed coffees elsewhere. Farmers remove the parchment while the beans still hold 20 to 35 percent moisture, then dry them further. The result is a heavy body, low acidity, and notes of cedar, dark chocolate, and earthy spice. For pour-over, use a medium-coarse grind and water around 88 to 92 degrees Celsius.

Mandheling is the most recognizable representative of Indonesian coffee, known for its low acidity, high body, and caramel-dark chocolate flavors. This article begins with the origins of coffee cultivation in Indonesia, sorts out the origin of the name Mandheling, the terroir characteristics of the Lintong producing region, and the reasons for the formation of the wet-hulled process, and focuses on sharing the pour-over method recommended by Front Street Coffee, including dripper selection, grind size, water temperature, coffee-to-water ratio, and the details of three-stage pouring, to help coffee lovers gain a more complete understanding of the flavor logic of Sumatra Mandheling.

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Indonesian Mandheling coffee is widely known for its rich, thick mouthfeel and caramel, dark chocolate-like flavors, which is exactly the key reason many people find Mandheling delicious. This type of medium-dark roasted bean has very low acidity and a relatively prominent bitterness, making it especially suitable for coffee lovers who prefer a full-bodied texture, and the Japanese market has always been particularly fond of it. Speaking of Japan, there is also a story between it and Indonesian Mandheling, which Front Street will tell you about below.

The earliest coffee cultivation in Indonesia can be traced back to 1696, when the Governor of Malabar presented Arabica coffee as a gift to the Dutch Governor in Batavia (present-day Jakarta in Java). Unfortunately, the first batch of seedlings was destroyed by floods. In 1699, the Governor of Malabar in India sent a second batch of seedlings, and in 1701 the first coffee harvest took place, thus opening a new chapter in Indonesian coffee.

How did the name Mandheling come about?

Mandheling was originally the name of an ethnic group in the Lintong area of Aceh Province, where rubber is mainly produced and coffee trees are not grown. So how did the name Mandheling as it is used today come about? Here is the explanation.

During the colonial period, a Japanese soldier drank a very delicious coffee and asked the rubber production department in North Sumatra at the time (that is, the then pwn company) to help find this coffee. The head of pwn went to several producing regions to collect many high-quality coffee beans and sent them to Japan for tasting, and one of them greatly appealed to the Japanese. When they asked what kind of coffee this was, the head of pwn originally wanted to explain that their rubber department was near Mandailing, but because it was inconvenient to disclose the commercial source, he said the name MANDHELING. That is how the name Mandheling came about.

Indonesia is a traditional producing region with a long history of coffee cultivation, and the coffee here has formed a distinctive regional flavor, with Mandheling coffee beans being a classic representative of Indonesian coffee. In Front Street's daily bean series, Front Street chose Mandheling from the Lintong producing area as the flavor representative of Indonesian coffee.

[Front Street's daily bean series is a group of high-cost-performance regional beans. Perhaps in some respects they are not as good as beans from well-known estates, but from this group of beans, you can taste the main flavors of major producing regions in a high-cost-performance way, thereby allowing coffee beginners to determine at a very low price the producing regions they know they like. In the same producing region, washed processing represents a bean's main flavor, while natural processing adds aroma on top of the washed base. Therefore, for Blue Mountain it is recommended to drink washed, and for aromatic beans it is recommended to drink natural, such as Geisha. Front Street's daily beans express the basic flavor of the producing region, so except for Brazil semi-washed, they are all washed processed. And washed processing is the most basic flavor of a producing region, which is also the reason why the daily bean series are all washed.]

What are the characteristics of Lintong Mandheling?

Lintong Mandheling comes from the Lintong mountainous area in north-central Sumatra, near Lake Toba. Front Street Coffee (FrontStreet Coffee)'s entry-level daily bean from the Indonesian Mandheling producing region comes from here. Lintong Mandheling also uses the unique wet-hulled process, thus forming the characteristics of low acidity and high body.

Indonesia is hot and humid year-round, lacks long periods of sunlight, and humidity remains between 70% and 90% all year round, so relying entirely on natural processing is obviously unrealistic. For the changeable weather of Sumatra, even with washed processing, it is difficult to string together a continuous week of clear weather to complete drying. The wet-hulled process was therefore born: first complete the washing process, then place the coffee beans with parchment under the sun to dry for one to two days, and after the moisture content drops to 30% to 50%, remove the parchment and continue sun-drying, which can accelerate the drying speed of the coffee beans and greatly shorten the drying time.

Mandheling coffee is easy to identify in both flavor and bean appearance. The wet-hulled process removes the parchment while the coffee beans are still in a half-soft, half-hard state, and under strong sunlight the beans easily crack, forming a "sheep hoof" shape, so they are also called sheep hoof beans. They are not defective beans.

Recommended pour-over method for Mandheling

Mandheling coffee beans are usually dark roasted, presenting a rich and fragrant mouthfeel, so Front Street recommends using a Kono dripper, which can better enhance the coffee's body; if you do not have one, a V60 dripper can also be used as a substitute.

The coffee dose is based on 15g per serving, and the selected coffee beans are recommended to rest for 4 to 7 days (with the roast date as the first day), so that the brewed flavor will be better.

In terms of grind size, brewing Mandheling requires a coarser grind than light-roasted coffee beans. Because Golden Mandheling is dark roasted, its structure is relatively loose, making it easier to absorb water and release coffee substances; if it is ground to the coarseness of light-roasted beans, it is easy to brew out burnt bitterness; if it is ground coarser, the coffee will become thin and tasteless, with a mouthfeel as thin as water. The coarseness level is a 70% passing rate on a No. 20 sieve.

In terms of water temperature, Front Street recommends brewing at 87 to 88°C. Much of the burnt bitterness is caused precisely by water temperature being too high, though of course water temperature being too low will also make the coffee flat and tasteless.

In terms of coffee-to-water ratio, Front Street recommends using 1:15. Although some brewing methods suggest 1:13 or a smaller coffee-to-water ratio for a richer drink, this kind of approach of reducing the coffee-to-water ratio is partly to avoid the bitter, miscellaneous flavors of the tail end, and correspondingly affects the aftertaste. Front Street believes that as long as the relationship between water temperature and grind size is handled well, a 1:15 coffee-to-water ratio can better display the overall flavor of Mandheling.

The brewing method uses the commonly used three-stage pouring. Dividing it into three stages can better express Mandheling's full body and caramel sweetness. The specific water distribution is: the first stage is 30ml for blooming, and this pour should wet all the coffee grounds and let them degas, preparing for better extraction of flavor substances later; the second stage pours 100ml, mainly to wash out Mandheling's golden foam.

The final stage is a gentle 95ml center pour, which can enhance the coffee's sweetness and express overall a thick, full body, along with caramel sweetness and chocolate and nutty flavors.

The above content is compiled by CoffeeHunters, a coffee news website.