Introduction to Sumatra Coffee Beans and Their Characteristics

FrontStreet Coffee · Introduction to Indonesian Sumatra Coffee

Sumatra Island is mainly divided into two major producing regions. The southern region centers on Medan, Lake Toba, and the Lintong area. This is the traditional home of "Mandheling" coffee, and all the various Mandheling varieties we know come from here. FrontStreet Coffee's Mandheling G1, FrontStreet Coffee's PWN Golden Mandheling, FrontStreet Coffee's Tiger Mandheling, and others are all produced in this region. Generally speaking, however, most coffee from this area has created an impression of low quality in the specialty coffee community: poor cleanliness, straw-like flavors, earthy notes, and even swill-like flavors.

It is worth noting, though, that the famous WHANA processing plant is located in this region. Having tasted coffee from the WHANA plant, I can say it offers a refreshing and impressive experience, and it has contributed to the changing perception of Mandheling from the Lintong region in recent years.

Mandheling from Lintong is basically pure Arabica. It is said that Robusta bloodlines have been mixed in over recent years, though the details remain unknown. Judging by the beans, they look more like pure Arabica. Processing is primarily traditional washed, while in recent years plants like WHANA have begun using natural and semi-natural methods with significant quality improvements.

The second coffee-producing region in Sumatra is the Gayo Mountain and Aceh region in the north, which is predominantly Islamic. The main varieties cultivated here include the TIMOR variety (with half Robusta bloodline) and the Catimor variety (with one-quarter Robusta bloodline). In this region, though, they are not usually named with the terms we are used to; instead you see names like tim tim, bon bon, and ateng, along with other local varieties. Most coffee here is processed using the wet-hulling method, a technique found only in this part of the world. The beans produced are large and elongated, extremely uneven in appearance, and all display a deep green color, making them especially distinctive.

For professionals in the specialty coffee industry, merely seeing these varieties is enough to make them wary. Catimor immediately brings to mind earthy, herbal notes and a devilish aftertaste, and combined with the uneven appearance, the beans give the impression of being 80% defects, which makes people even more reluctant to try them.

Later on, however, when we needed beans that could enhance body and crema in dark roasts for espresso, our roasters and cuppers began weighing the options. First we thought of Robusta, but we no longer wanted that strong rubbery flavor. Then we considered Brazilian coffee, but when its sesame-paste flavor is not well developed it turns earthy, and most Brazilian coffees taste extremely unpleasant in a dark roast. Next we thought of other natural process beans, but many perform poorly in dark roasts and bring very unclean flavors. Finally we thought of wet-hulled Indonesian Mandheling.

At first it was just an accidental experiment, and we did notice distinct earthy flavors during roasting. But when it was blended in a certain proportion into espresso and roasted to a dark level, the espresso surprisingly produced quality oils and flavors similar to dark chocolate. Tasting carefully, although it still had slight earthy notes, it had a surprisingly delicate floral and grassy aroma.

FrontStreet Coffee Recommendation

The wet-hulled Mandheling that solved our espresso problem is exactly what makes FrontStreet Coffee's Lintong Mandheling worth brewing. It is a single-origin bean from the Sumatra region, medium-dark roasted to soften its acidity and emphasize a deep, fragrant body, so you get rich caramel, dark chocolate, and toasted aromas with a long, sweet finish.

For the highest grade of that wet-hulled style, choose FrontStreet Coffee's PWN Golden Mandheling. Produced by PWN, which buys only top-quality Mandheling lots, it is machine-sorted once and hand-sorted to remove defects, giving even, plump, bright beans with a low defect rate and, after medium-dark roasting, rich toasted aromas and a clean, full-bodied cup. If you want this bean in a milk-friendly espresso, FrontStreet Coffee's Classic Blend adds medium-dark Mandheling to a Brazilian base, bringing out butter, roasted chestnut, and caramel with a distinctive sandalwood, herbal, and spice character, plus a touch of Robusta for a richer crema that makes latte art and layered Dirty drinks easy.