How does coffee processing shape Wahana Estate Mandheling flavor?
Wahana Estate, near Lake Toba in Sumatra, produces a naturally processed Mandheling that departs from the region's usual wet-hulled style. Grown at roughly 1,000 to 1,700 meters on volcanic soil with Bourbon and Typica varieties, the 2020 harvest G1 lot cups with tropical fruit and fermented notes rather than the heavy herbal profile Mandheling is known for.
Making natural coffee in Indonesia is difficult because of high humidity, and early lots fell short until the coffee process order was rearranged. Wahana Estate, founded in 2005 in the Sidikalang area, relies on cool conditions and a day-night temperature swing above 10°C, pushing red cherry sugar content above 13 percent.
When people mention Mandheling, most first think of the full-bodied herbal notes brought by the wet-hulling process, but Indonesia does not have only one processing method. At the Wahana Estate in the Lake Toba region of Sumatra, an improved natural process has successfully produced a naturally processed Mandheling with a completely different style. This article will walk you through Wahana Estate's growing background, the evolution of its processing flow, as well as the cup profile of this bean and Front Street's recommended brewing method, so you can experience the unique charm of tropical fruit intertwined with fermented notes.
Most people's impression of Mandheling is that it is wet-hulled, but Front Street wants to tell everyone that coffee processing methods are not set in stone. Even in humid Indonesia, there is also naturally processed Mandheling. The naturally processed Mandheling from Wahana Estate at Lake Toba in Sumatra is a Mandheling that stands out from the rest. Producing natural coffee in Indonesia is extremely difficult, and the first obstacle is the extremely humid climate. The quality of early production was not ideal, and it was only after the order of the processing flow was adjusted that success was finally achieved. Front Street greatly admires this spirit of exploration; without the wisdom and hard work of coffee farmers, we would not have the chance to taste such wonderful specialty coffee.
Sumatra Wahana Estate Natural Mandheling
Coffee region: Lake Toba
Altitude: 1,000 to 1,700 meters
Soil: Volcanic soil
Coffee varieties: Bourbon, Typica
Processing method: Natural process
Harvest year: 2020
Grade: G1
Coffee region
Wahana Estate was established in 2005 and is located near LeaMungkur Village in the Sidikalang area of North Sumatra, Indonesia. Sidikalang has been one of Indonesia's famous coffee-producing regions since ancient times. The area where Wahana Estate is located has an altitude of between 1,200 and 1,500 meters, annual rainfall of 2,000 to 3,000 millimeters, and the region also has a relatively cool climate and a day-night temperature difference of more than 10°C. Based on these conditions, the sugar content of Wahana's red cherries is above 13%. In 2006, Wahana Estate was established in the Sidikalang area northwest of Lake Toba in North Sumatra. It is a farm using advanced equipment. On the 460-acre farm, crops such as coffee and vegetables are grown. The coffee department on this farm introduced processing equipment as advanced as that in Brazil, and initially used 100 acres of land to grow coffee. In the autumn of 2008, the refined processing plant was completed. At first, of course, it mainly produced ordinary Mandheling, but it had always been Wahana's wish to produce a different kind of Mandheling, so it began a new production plan—natural Mandheling.
The coffee farmers in this region basically process coffee by hand, so they already possess quite good experience and techniques. Therefore, Wahana Estate combined the farmers' skills with advanced equipment to achieve the goal of producing natural Mandheling. At the beginning, Wahana Estate used a semi-open-air space equipped with skylights for drying, attempting to produce 100% natural Mandheling. However, because the drying period was severely affected by the humid climate, the stability of quality was not ideal. Therefore, the processing flow was finally adjusted to natural sun-drying in the early stage plus machine drying in the later stage, and through this unique processing method, Wahana's distinctive natural Mandheling flavor was refined. Natural Mandheling is different from traditional processing methods. It requires experienced farmers to harvest fully ripe coffee cherries, which are then naturally sun-dried for several days, then completely air-dried using a dryer, and finally dehulled using equipment specially designed for natural beans. Only in this way can a high-quality natural flavor be produced.
Wahana Estate is still a relatively young estate and continues to develop year by year. The estate covers an area of about 500 hectares. The estate owner plans to expand the estate's coffee planting area as much as possible in the coming years. A large part of Wahana Estate is a protected forest coverage area, and this protected area includes many native plant and tree species around valleys and rivers. Another 30 hectares of Wahana Estate are used for coffee breeding to increase the yield of single-origin coffee grown on a large scale. New seedlings are cultivated in sandy seedbeds for 3 months, then transplanted into seedling plastic bags for 7 to 8 months. After that, the coffee seedlings are planted in already divided planting areas and carefully marked for future variety identification. The local seedling varieties currently planted include: Long Berry from Aceh, Toraja from Sulawesi, Rasuna from Sumatra, S795 and dong Sari from Java. International seedling varieties include Villa Sachi from Costa Rica, Caturra from Costa Rica, Cattuai from Costa Rica, and Typica from Colombia. In order to produce high-quality North Sumatra coffee, Wahana Estate has planted shade trees on the farm and uses organic fertilizer (compost), practicing sustainable agriculture. Wahana Estate isolates different coffee varieties by plot and harvests them separately to unleash the potential of each variety. In addition, only red cherries can be harvested and then processed separately.
Processing method
The processing method of this bean is not the wet-hulling method unique to Indonesia, but the more difficult natural process. The natural process first requires manually selecting defective coffee beans, as well as unripe or overripe coffee cherries. After that, the coffee cherries are evenly spread out on the drying patio and need to be turned several times each day. The drying process usually lasts about 2 to 3 weeks, depending on the local climate, and Indonesia's humid and rainy climate makes this time even longer. When the moisture content inside the coffee beans drops to 11-13%, the natural drying step is complete. After drying is completed, the outer shell of the coffee cherries has already become dry and hard, and it only needs to be removed with a huller.
Front Street Wahana Natural Mandheling roasting curve
Front Street Wahana Natural Mandheling cup profile
Front Street Wahana Natural Mandheling brewing parameters Coffee dose: 15 g Ratio: 1:15 Water temperature: 90°C Grind size: BG # 6sf Dripper: Hario v60 #01 dripper
Front Street Wahana Natural Mandheling brewing process: For the first pour, add 30 g of water and bloom for 30 seconds; for the second pour, add 95 g of water (the digital scale shows 125 g), finishing in about 1 minute; for the third pour, add 100 g of water (the digital scale shows 225 g), finishing in about 1 minute 40 seconds.
Extraction time: 2 minutes 10 seconds, remove the dripper to complete brewing.
Flavor description: tropical fruit, fermented notes, moderate acidity, smooth mouthfeel, obvious sweetness.
The above content is compiled by CoffeeHunters, a coffee news website.
