Sumatra Coffee: What’s the Coffee Expert’s Verdict?

Coffee from Sumatra is a unique experience. But it’s not for everybody. In this article, I take a close look at the details of this idiosyncratic bean.
Sumatran coffee is one of the most interesting beans in the coffee world today.

It’s a bean that packs a punch. Many people love it, but some also hate it.

See, while many of the big coffee producing regions by now are doing things in a similar ‘professional’ way, the farmers in Sumatra still stick to their ‘original’ and more crude style of processing.

In that sense, it’s unlike most other coffee out there.

Read on, if you want to understand all the little details of this unique bean.

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If you want to try a real Sumatran, this is a good bet. It has notes of nuts and tobacco, which is typical of the region. It’s full bodied and low in acidity.

It’s roasted by the legendary coffee company Stumptown, so you know the coffee beans are sourced from the best farmers on the island.
Stumptown Coffee...

Where is Sumatra coffee from?

Sumatra is an island belonging to Indonesia. It’s the 6th largest island in the world and home to more than 50 million people. Along with Borneo and Java, it is one the three main islands comprising Indonesia.

Coffee production on the island of Sumatra is thought to have begun around 1884, near Lake Toba, which is the largest volcanic lake in the world. Today, Sumatra is the largest coffee producing region in the country.

sumatra island coffee

Bonus-Info: mystical historical events surround Sumatra and Lake Toba. A volcano erupted around 75.000 years ago in a so-called super-volcanic eruption. Speculation suggests that this lead to mass extinction of humans in the area and a global climate change.

What is Sumatra Coffee? A bit of History

As you might know, Indonesia and coffee have a long history. Initially, coffee grew wild in Ethiopia, but via Yemen, the Dutch colonialists brought the plant to Indonesia in 1699.

Here it thrived, and Indonesia quickly became the largest coffee producing nation in the world. The coffee was exported from Jakarta on the island of Java, and that’s how Java became almost synonymous with coffee everywhere in the world.

This isn’t that strange since the bags the coffee was packed and exported in all said ‘Java.’ A bit like how tissue is often called a Kleenex, even though it’s a brand name.

Sumatra Coffee Facts

  • Sumatra is an Indonesian island with fertile volcanic soil.
  • It’s the largest coffee producing region of Indonesia
  • The taste of the coffee from Sumatra is often described as earthy, rich, chocolate, and even mushroomy
  • The beans are typically low-acid (but this also has to do with the roast and processing)
  • The most famous subregions of Sumatra are Mandheling, Lintong, and Gayo.
  • Sumatran coffee is often processed with the ‘gilling basah’ method.

Is Sumatra coffee lower in acid?

Bali Kintamani...

Coffee from Sumatra is known for being low acid coffee. There are several reasons that this is the case, but the way the local farmers process the coffee is the most important one. The process is known as wet hulling or ‘giling basah in the local language. It’s a more crude and random way to process the cherries compared to the washing method popular in Latin America.

When the coffee cherries are picked, they are depulped right away. The seeds – what we know as ‘the beans’ – are then put in a large plastic sack and left to ferment over the night. The next day the remaining pulp is removed by hand, and the beans are left to dry on a patio.

Soon after, a middleman will show up and buy the beans, and then he’ll take them to a warehouse and remove the parchment layer, and let them dry further before the export.

The processing changes the flavor

Compared to coffee that is washed at a station and dried more carefully, this leads to a more earthy and less acidic flavor. The body and mouthfeel are enhanced, but the subtle notes of stone fruit and berry are muted.

For many coffee buyers, especially in specialty coffee, this means that Sumatra coffee isn’t that appealing. However, many old-school coffee drinkers appreciate a dark and brooding character when it comes to coffee, so for them, it might be worth checking out.

It should also be said, that there are of course exceptions to the rule. Not all Sumatran beans are wet hulled nor low in acidity. One of the most memorable coffees, I had in 2016 was from Kerinci, and that had plenty of acidity and interesting flavor notes.

Is Sumatra a dark roast?

2lb Sumatra Gayo...

A lot of people think that coffee from Sumatra is necessarily a dark roast, but this is entirely up to the roaster who deals with this bean. In your case, this probably means an American roaster or coffee company.

But since the flavors that many people like about Sumatran coffee is more prominent at a medium to dark roast level, this is what will most likely be enhanced by the roaster.

Starbucks and similar chains buy vast quantities of coffee from this region of the world and roast it quite dark to use it as a base in their espresso blends. This is maybe what has given birth to the idea of a specific ‘Sumatra roast.’

The fact is, however, you can roast any coffee just the way you like it. If you’re looking for a roast with low acid and plenty of chocolate, leather, and nuts, then make sure that your coffee is a medium-dark roast or what coffee experts like to call a ‘full city.’

Types of coffee grown on Sumatra

There’s a wide range of coffee grown in Indonesia. This is due to the long history of coffee here, compared to most other places.

  • Typica was the first varietal planted on Java and Sumatra back in the days, but this type of plant was almost entirely wiped out by leaf rust more than hundred years ago. A few local varieties of typica can still be found at really high altitudes on Sumatra.
  • Several of the most commercially viable arabica lines in Indonesia do have a bit of robusta heritage to make them more disease resistant. This is the case with both Catimor, and Hibrido de Timor.
  • Linie S, another widespread disease resistant varietal, is a natural mutation of Liberica and Bourbon, originating in India.
  • There’s also a group of Ethiopian coffees brought to Sumatra in the late 1920’s that are still viable today. They are called Abyssinia and Rambung.

Indonesia also grows enormous quantities of robusta coffee, but this kind is usually found at lower altitudes and is used for instant coffee or consumed domestically. This kind of coffee is cheap, but frankly, it tastes so harsh that it won’t be of any interest to the average Western coffee drinker. Trust me on this one!

The Coffee Chronicler’s Verdict: Every coffee drinker should try a single origin Sumatran coffee at least once. Since Indonesia is such a huge producer as well as an important coffee country historically, we owe it to the coffee gods. If you’re a third wave coffee drinker, you should seek out a one of the premium washed coffees from Kerinci, and I’m sure you will have a blast.


Top Featured Image: Dennis Tang Source
about the author

about the author

Hey, I'm Asser Christensen from Denmark – the founder & editor of this site.

I have been crazy about caffeine for almost as long as I can remember. Today, I'm a licensed Q Arabica Grader and full time coffee writer.

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