What makes Golden Mandheling coffee different from other Sumatras?

Golden Mandheling is a PWN Pwani Coffee Company selection from Sumatra, produced through machine sorting plus repeated rounds of hand-picking. It comes mainly from the Lintong area and the Lake Toba region of North Sumatra, with Gayo and Aceh coffee also falling under the Mandheling name. The wet-hulling process and the ateng variety shape its heavy body and low acidity.

Dutch colonists moved Java Mandheling north to Lake Toba in 1888, and the Lintong area's finest lots include Sidikalang, Bergendar, Siborong borong and Telok Sanggul. Lake Tawar in Aceh has recently matched or exceeded Lake Toba in both quality and volume. Green bean analysis, roast profiling and staged pour-over parameters follow from that base.

Golden Mandheling is the benchmark of Indonesian Sumatra coffee, produced by PWN Pwani Coffee Company and made through machine sorting and multiple rounds of hand-picking. This article begins with the producing regions, variety composition, and the principles of the wet-hulling process, then extends to green bean analysis, roast profile design, and cupping performance, and finally provides complete pour-over brewing parameters and a staged pouring plan. It also introduces specific recommendations from Front Street Coffee for the roasting and brewing of PWN Golden Mandheling, making it suitable for coffee enthusiasts who want to understand the source of Mandheling's flavor and practical methods.

PWN GOLDEN MANDHELING

Golden Mandheling

01 | Introduction to the Producing Regions

Indonesia's coffee-growing map mainly covers the three islands of Sumatra, Java, and Sulawesi, among which Sumatra produces the most famous Mandheling.

Mandheling is also called Sumatra coffee. Most coffee from North Sumatra is Gayo, with ateng as the main variety; the area around Lake Tawar at the northern end of the island can be called Aceh coffee or Tawar Lake coffee; Lintong in South Sumatra and the area around Lake Toba are also classified under the Mandheling name. The Lintong region is the core producing area of Mandheling, and its four finest varieties are Sidikalang, Bergendar, Siborong borong, and Telok Sanggul.

Lake Toba is located in the central part of North Sumatra Province. In 1888, Dutch colonists moved "Java Mandheling" north to the Lake Toba area, thus writing the legendary modern chapter of Mandheling.

Lake Tawar is located in the central part of the Aceh Special Region, at the northernmost tip of Sumatra Island, with a water area less than one-tenth that of Lake Toba. But in recent years, both the coffee quality and production in this area have surpassed Lake Toba.

The Gayo Mountains are located in the Aceh producing region of North Sumatra Province, and most of the coffee farmers working there are local farmers. The word Gayo comes from the name of a tribe in the Aceh region of Indonesia. This area has ideal growing conditions, a long history and culture, and a distinctive flavor profile. Coffee there is generally grown organically, without chemical fertilizers, and it is regarded as a green coffee production area in the world. Therefore, Gayo coffee is also often called green coffee or Gayo organic coffee.

What is Golden Mandheling?

To talk about Golden Mandheling, we must start with PWN. This abbreviation often appears alongside the name Mandheling coffee, but it is actually the abbreviation of a company—Pwani Coffee Company.

This company is extremely famous locally in Indonesia, and its main business is purchasing Mandheling coffee. It has brought almost all of Indonesia's best producing regions under its control, so most beans produced by PWN are unique specialty coffees.

Golden Mandheling is exactly a product launched by this company. After the green beans are purchased, they first undergo one machine sorting, then more than three rounds of hand-picking, selecting plump and defect-free beans. Only these excellent beans that pass层层 screening like a talent contest can be classified as Golden Mandheling grade.

The purpose of machine sorting is to first screen out beans that must reach a specification of 18 mesh or above, while the subsequent multiple manual selections are to remove irregular defective beans. Once the defect rate is reduced, the quality of Mandheling coffee naturally improves greatly.

However, PWN has registered Golden Mandheling as a trademark, which means that from now on only Golden Mandheling produced by PWN can be considered true Golden Mandheling. Many beans on the market that are not produced by PWN but bear the name Golden Mandheling should actually be called specialty Mandheling.

The Golden Mandheling coffee beans sold by Front Street Coffee all come from PWN. At Front Street's offline stores, you can see the certification certificate issued by PWN, as well as green bean burlap sacks printed with the PWN logo.

02 | Processing Method

Wet hulling, also called wet hulling, is known in the local language as Giling Basah, and it is a traditional Indonesian coffee processing method. Judging by the name alone, wet hulling seems quite similar to wet processing (washed processing), yet the flavors of the two in cupping are completely different. Coffee processed by wet hulling is usually full-bodied and intense, with a very distinct character.

Steps of the Wet Hulling Process

① Remove the skin and pulp, keeping the parchment and mucilage

② Ferment in a water tank

③ Wash off the mucilage

④ Sun-dry with parchment for 2-3 days, to a moisture content of 20-24%

⑤ Remove the parchment

⑥ Dry the green beans to a moisture content of 12-13%

⑦ Prepare for export

Why use wet hulling?

a. Climatic reasons

The tradition of using wet hulling in Indonesia begins with the local weather. Indonesia's humidity remains between 70-90% all year round, typhoons are continuous, and in some areas annual rainfall can even reach 2,000 mm. Green beans fear rain the most, so how does Indonesia still produce rich, full-bodied Mandheling coffee under such harsh weather conditions? The answer is wet hulling.

Under tropical climate conditions, coffee generally takes 2-3 weeks on average to dry completely. But Indonesia's climate is so humid that drying coffee becomes a major challenge. Coffee drying must take longer, and during this time the coffee still maintains relatively high moisture, making it easier for bacteria to invade the green beans.

The drying process of conventional washed processing is carried out with the parchment still on, thereby protecting the green beans to some extent from external damage. However, as can be seen, wet hulling removes the parchment before the final drying step. In this way, sunlight directly hits the surface of the green beans, and the green coffee dries rapidly, 2-3 times faster than washed processing.

b. Economic benefits

Dutch colonists first introduced coffee to Indonesia in the 17th century. These colonists sought more and faster economic returns, and wet hulling greatly shortened the time spent on the farm and also significantly reduced labor costs. This coincided with the investment mindset of pursuing quick profits and lowering costs. This is also one reason that drove the wet hulling method.

c. Defects and kuku kambing (goat hoof beans)

When wet hulling removes the parchment, the coffee's moisture content is still as high as 20-24%, whereas in general processing methods the coffee is only hulled after the moisture content drops to 10-12%. In a semi-dry state, the parchment sticks to the surface of the green beans, making it more difficult to remove than when fully dry, and the hulling process requires greater friction.

On the other hand, semi-dry green coffee beans are very fragile at this point, far less hard than fully dried green beans, so the beans are relatively easy to crush and form small gaps. These are what we often call horse hoof or goat hoof beans (locally called kuku kambing).

The extremely fast speed of wet hulling also causes Mandheling to have a relatively high defect rate. Processing plants arrange employees to hand-sort defects, generally DP (double-picked) and TP (triple-picked). Mandheling that has undergone triple-picking will be superior to double-picked in terms of defect rate.

As for the flavor of wet-hulled coffee, aside from those subtle differences, it is generally believed that wet-hulled beans have earthy, smoky, and chocolate notes, with acidity described as low, and a full-bodied yet rather dull character.

The low acidity comes from a shorter, weaker fermentation process and a longer drying time. If you have forgotten about wet hulling's fermentation, go back and take another look. As for flavors such as the earthy notes of wet-hulled beans, opinions vary widely. Some say this is related to the bean varieties used in wet-hulling regions (Timor and Catimor lines: with Robusta ancestry), some say it is the result of organic interactions between the green beans and the outside environment, and some even say it is because there are too many defective beans.

03 | Green Bean Analysis

Front Street PWN Golden Mandheling Gold Mandheling green beans

Front Street Coffee—Front Street PWN Golden Mandheling coffee beans

Producing region: Gayo Mountains, Aceh Province, Sumatra, Indonesia

Company: PWN Pwani Coffee Company

Altitude: 1100-1600 m

Grade: G1 triple-picked

Processing method: wet hulling

Front Street Coffee chooses to drop the beans before second crack, retaining a little gentle acidity. The mouthfeel is high in sweetness, fragrant and full-bodied. Flavor: baked toast, pine wood, caramel, cocoa, with a slight herbal earthiness.

In the specialty coffee system, Sumatra coffee is a fascinating existence. You see, the famous Mandheling is actually not the name of a producing region, nor the name of a coffee variety, and even its bean variety sources are so mixed.

04 | Common Coffee Varieties in Indonesian Producing Regions

Ateng

It is a hybrid variety between Arabica and Robusta, with several subtypes, widely planted in Sumatra and other Indonesian islands. To put it plainly, it is a branch of Catimor, and Ateng is the local name.

Djember

Looked up on Baidu, Djember is a place name in Sumatra. It seems quite mysterious, but the variety is actually S-795. Because this bean variety was spread to the island by the Jember Coffee Research Center, locals call S-795 by this name.

What is S-795? It is a hybrid created by an Indian botanist by crossing the Typica mutant Kent with S-288.

What is S-288 then? It is a natural hybrid between Arabica and Liberica.

Tim Tim

Tim Tim is a bean from Indonesia. Because of its long shape, many people call it horse-face bean, and some also call it long-strip Mandheling. In fact, Tim Tim is not a pure variety, but a variety formed by the natural hybridization of Arabica coffee trees and Robusta coffee trees.

This variety was discovered on Timor Island in the 1940s and was cultivated because of its natural disease resistance. In the Americas this variety is called Hybrido de Timor, abbreviated as Tim Tim, and in Indonesia this variety is also called Bor Bor.

05 | Roast Analysis

Front Street Coffee notes that Golden Mandheling is a green bean with relatively high moisture, showing a relatively large moisture deviation from sun-dried beans, so special attention must be paid during dehydration. For green beans with high moisture content, you can close the air damper immediately after loading the beans, let them steam for 30 seconds, then open it to 3, until the color of the green beans turns light green or white, then open the air damper to 4, and after first crack open it to 5 (maximum).

Front Street Coffee recommends keeping good data records before roasting, including the coffee beans' moisture content, density, origin, processing method, and the roasting room's ambient temperature and humidity, and planning your roast profile. During roasting, record the relevant chemical and physical changes, all of which will help you better understand the final roasting result and help improve the roast profile.

Roast profile:

Charge when the drum temperature reaches 200°C, set the air damper to 3, after 1 minute adjust the heat to 160°C, keep the air damper unchanged, roast until the temperature reaches 148°C, when the bean surface turns yellow and the grassy smell completely disappears, dehydration is complete, adjust the heat to 140°C, and change the air damper to 4;

At the 9th minute, ugly wrinkles and dark streaks appear on the bean surface, and the toast aroma clearly turns into coffee aroma, which can be defined as the prelude to first crack. At this time, listen carefully for the sound of first crack. When first crack begins, reduce the heat to 60°C and fully open the air damper (adjust the heat very carefully, not so low that there is no cracking sound), and drop the beans at 204.5°C.

Cupping report:

Through comparative cupping, Front Street Coffee found that Front Street PWN Golden Mandheling tastes cleaner than Lintong Mandheling. Mandheling's original herbal, earthy, and woody notes are almost gone, but the caramel sweetness is stronger, and the fruity acidity is also brighter and more elegant. Ordinary Lintong Mandheling is usually best dropped after second crack, which can effectively reduce off-flavors, but Golden Mandheling has very good transparency and sweetness whether dropped before or after second crack, and the space for roasting interpretation is broader.

06 | Brewing Analysis

Front Street PWN Golden Mandheling coffee beans are roasted to a deep level. To let everyone taste a more complete coffee flavor, all coffee beans sold are shipped within 5 days after roasting is completed, ensuring 100% fresh roasting.

Medium-dark roasted beans generally have a relatively high dehydration rate, so they are lighter in weight. During brewing, the grounds do not completely sink to the bottom, and as soon as water is poured in it is immediately absorbed. Because degassing is vigorous, there are bubbles all around the grounds, thus creating channels. The fresher the beans, the longer these channels last, causing the water level to drop quickly. I generally use a thick stream of water and slowly go in circles.

1. Dripper: KONO

2. Water temperature: 88°C

3. Grind size: medium-coarse grind (70% passing through a Chinese No. 20 standard sieve)

4. Roast level: medium-dark roast

5. Coffee dose: 15 g

6. Coffee-to-water ratio: 1:15

Staged pouring: Use twice the weight of the coffee grounds in water to wet the coffee bed, forming a dome, and let it bloom for 30 s. Then pour in a small stream in circles from the inside out until 125 g, pause, and wait for the coffee bed to drop to half the height of the dripper. Continue pouring the third stage with the same fine stream until 225 g, then wait until all the coffee liquid has filtered through, remove the dripper. The time is about 2 minutes. Finally, swirl the carafe to mix the coffee liquid evenly and it is ready to enjoy~

The hand-brewed Front Street PWN Golden Mandheling coffee has an overall multi-layered, rich, and full-bodied profile with a clean mouthfeel. It has nutty and caramel aromas, with chocolate notes, a long finish, and high balance.

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