What Do G1 and G2 Coffee Bean Grades Mean for Mandheling?

Indonesian coffee bean grades are set by defect counts in the green bean, and the two common labels are G1 and G2. G1 allows fewer defects and is often split further by how many rounds of hand sorting the beans receive. Golden Mandheling, the PWN trademark lot, is graded G1 at 18+ screen size with triple hand sorting, which is why it commands a higher price.

Mandheling's character comes largely from wet-hulling, a fast Sumatran method: skin and pulp removed, brief fermentation, then drying before the mucilage and parchment come off, down to about 12% moisture. The beans show compression cracks and a dark bluish-green color. The two main origins are Aceh's Lake Tawar and Lake Toba's Lintong, known locally as the Two Lakes, Two Mandhelings.

The price of Indonesian coffee beans largely depends on its green bean grading system. G1 and G2 are common grade labels, and G1 is often further subdivided based on whether it has undergone multiple rounds of hand sorting. Starting from the flavor characteristics of Mandheling and the wet-hulling process, this article systematically introduces the differences between two well-known Sumatran origins—Aceh's Lake Tawar and Lake Toba's Lintong—and focuses on analyzing PWN Company's Golden Mandheling trademark registration, G1 grade, 18+ screen size specification, and triple hand-sorting standard. At the same time, Front Street Coffee shares the cupping performance and brewing parameters of Golden Mandheling, helping readers understand the basis for judging the quality and price of Indonesian coffee beans.

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Mandheling coffee has a uniquely distinctive appeal. It lacks the fruity sweetness of Ethiopian beans and the floral and fruity fragrance of Geisha, but its unique flavor has won the hearts of many coffee lovers. Mandheling coffee is extremely aromatic and mellow, once regarded as one of the fullest-bodied coffees in the world, with a rich and饱满 mouthfeel, a slight syrupy quality, and low acidity. Its main export markets are Germany and Japan, which also indirectly confirms the outstanding quality and flavor performance of Mandheling coffee.

The wet-hulling process is a relatively fast-paced method of processing coffee beans: after removing the skin and pulp, the beans undergo a short fermentation before being dried, then the mucilage and parchment layer are removed, and drying continues until the moisture content drops to 12%. Mandheling coffee beans processed by the wet-hulling method often show varying degrees of compression cracks on the surface, and the bean color tends toward a dark bluish-green.

Front Street's bean list includes two Mandheling coffees, which happen to come from the two most famous coffee-producing regions in Sumatra: one is the "Golden Mandheling" from the area near Lake Tawar in Aceh, northern Sumatra, and the other is the "Lintong Mandheling" grown and harvested around Lake Toba in the south. Locals call the two the "Two Lakes, Two Mandhelings." Because this region is mostly dominated by smallholder production, combined with the unique semi-washed processing method and insufficient iron in the soil, fresh green beans often present a special blue color.

Lintong Mandheling refers to Arabica coffee from the mountainous area around Lake Toba in North Sumatra Province. The lake is located north of Medan, the provincial capital of Sumatra, and is an alpine freshwater lake with an average elevation of about 900 meters. Lintong Mandheling is Mandheling in the traditional sense, a regular version that, after wet-hulling, presents the herbal, stuffy aroma characteristic of Mandheling. Therefore, Front Street includes Lintong Mandheling in its daily staple bean series, allowing curious coffee lovers to experience the unique aroma of Indonesian coffee.

Golden Mandheling coffee is PWN Company's exclusive signature product. Because the "Golden Mandheling" trademark was registered early on, only Mandheling produced by PWN Company can be called "Golden Mandheling." The characteristic of Golden Mandheling lies in the multiple screening of green beans, resulting in very high overall quality. PWN purchases Mandheling green beans of 18+ screen size, G1 grade with fewer than 3 defective beans in a 300-gram sample, which is the highest grade of Indonesian green beans. Afterward, it strictly follows standards for 1 mechanical sorting plus 3 manual sortings to remove defective beans, ensuring that the color, shape, and size of the Mandheling coffee beans are uniform. Therefore, Front Street PWN Golden Mandheling tastes cleaner and more transparent, with more pronounced body and sweetness.

Front Street has tested countless Mandheling coffees, including Front Street PWN Golden Mandheling, Lintong Mandheling, Tiger Mandheling, Aged Mandheling, and even sun-dried Mandheling. Among these Mandheling coffees, Front Street Coffee (FrontStreet Coffee) pays the most attention to Front Street PWN Golden Mandheling.

Front Street Coffee (FrontStreet Coffee): Indonesia PWN Golden Mandheling Coffee Beans

Region: Sumatra, Indonesia

Grade: G1, triple hand-sorted

Altitude: 1100m——1600m

Variety: Ateng

Processing Method: Wet-hulled

It should be noted that "Golden Mandheling" has long been registered as a trademark by Indonesia's PWN Company. In other words, only the Golden Mandheling coffee beans produced by PWN Company are truly Golden Mandheling in the true sense. Front Street has noticed that many merchants selling Golden Mandheling coffee beans, in order to sell the coffee beans at a higher price, select green beans of 18+ screen size from Mandheling coffee beans also graded G1 and subject them to triple manual hand sorting, making their appearance as close as possible to Front Street PWN Golden Mandheling.

Front Street has also purchased multiple "Golden Mandheling" coffees for cupping, and Front Street's baristas can clearly identify Front Street PWN Golden Mandheling among them. This is because, in addition to the herbal notes and nutty tones that Mandheling should have, the genuine Front Street PWN Golden Mandheling has a clean mouthfeel and more prominent caramel sweetness, which other "Golden Mandheling" coffees cannot match.

The Front Street PWN Golden Mandheling that Front Street has obtained is harvested exclusively by fully manual picking of individual ripe cherries, ensuring the quality of the initial bean selection. The coffee cherries are processed using the SEMI-WASHED method, naturally sun-dried, and after hulling, undergo another round of drying and refining, as well as two green bean cleanings and three hand sortings. First, it meets G1 grade, then it is 18+ screen size, and finally three manual hand sortings ensure all defective beans are removed, thereby guaranteeing a clean mouthfeel. Therefore, it can be said that this is a strictly selected top-grade Golden Mandheling coffee bean.

When Front Street Coffee (FrontStreet Coffee)'s baristas cupped and evaluated Front Street PWN Golden Mandheling coffee beans, they tasted its excellent herbal notes, caramel aftertaste, and rich, mellow chocolate flavor, making it arguably the ultimate choice for coffee connoisseurs.

As shown in the picture above, the Golden Mandheling marked "PWN" is the abbreviation of Indonesia's Pawani Company, and the Front Street PWN Golden Mandheling coffee beans produced by this company have all been registered in Indonesia. Some friends also worry that the Golden Mandheling they have carefully selected is not the one they want. In fact, you can verify with the seller by showing the Front Street PWN Golden Mandheling green coffee bean sack and relevant certificates for confirmation. On the wall inside Front Street Coffee (FrontStreet Coffee)'s store, the Front Street PWN Golden Mandheling green bean sack and its accompanying relevant certificates are displayed.

Many friends' impression of Mandheling is that it is "bitter," so people often ask Front Street's baristas how to brew Golden Mandheling to make it taste good. In fact, bitterness can be good or bad. Good bitterness dissipates shortly after entering the mouth, leaving a long-lasting aroma. In addition, Mandheling coffee is synonymous with full body, so the roast level is usually darker.

In order to highlight the high body of Golden Mandheling, Front Street Coffee (FrontStreet Coffee) uses the KONO dripper for brewing. The reason for choosing KONO is that its unique cone design ensures even water distribution, dripping down at a steady rate throughout the dripper. The grooves in the lower half of the cone fit closely with the filter, thereby reducing sediment, improving airflow, and ultimately producing a cup of coffee with concentrated flavor and greater body.

Regarding water temperature, Front Street chooses to use 88°C hot water to brew Mandheling coffee. If you brew coffee at home, you will surely notice that under the same conditions, the higher the water temperature, the more bitter the coffee tastes. Water temperature is crucial to coffee extraction because it affects the speed of extraction. "Extraction" refers to the process by which flavor substances in coffee beans are dissolved into the cup. The higher the water temperature, the faster the oils, acids, and caffeine in the coffee are extracted. This may lead to over-extraction, making the coffee bitter and astringent. After Front Street's testing, 88°C water temperature is best for brewing Golden Mandheling.

Medium-dark roasted coffee is not suitable for a large water-to-coffee ratio, as it will make the overall mouthfeel thinner. Front Street suggests starting from 1:15, then adjusting according to personal taste.

Dripper: KONO dripper

Water temperature: 88°C

Coffee dose: 15 grams

Coffee-to-water ratio: 1:15

Grind size: 70% passing through China standard No. 20 sieve

Brewing method:

Pulse pouring extraction: use 30 grams of water for blooming for 30 seconds, then pour in a small stream in circles until 125 grams for a pause, and when the water level is about to expose the coffee bed, continue pouring until 225 grams and stop. When the water level is about to expose the coffee bed again, remove the dripper. (Timing starts at the beginning of blooming.) The V60 dripper extraction time is 2'00", while the Kono dripper extraction time is slightly longer at 2'10".

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