Sumatran coffees - always an exciting challenge
Sumatra has played a significant role in the long history of coffee.
Some of the most popular early blend combinations involved pairing Sumatran coffees with Yemeni heirloom lots to create the famous Moka.
With Yemen coffees now extremely rare and difficult to source, naturally processed Ethiopians like Harrar and Sidamo are better for combining with Sumatrans to become the famous "Mocha" blend.
These days, it is rare for Sumatra coffee to be used in a coffee brand's Mocha or Moka blend.
For nine years, Sumatran coffees have been in chronic short supply.
Most Import Brokers are less inclined to source Sumatran for fear of taints or being stranded with expensive coffee they can't sell.
There are two primary reasons for the ongoing shortfalls.
Firstly, adverse weather conditions can "ruin" crop yields and "spoil" the traditional wet hulling techniques used to process Sumatran coffees.
Putting aside the climate change argument, Indonesia has experienced many consecutive seasons of abnormally high rainfalls due to the effects of global warming.
Secondly, the more profound impact has come from the US market being the largest buyer of Sumatrans, and a few of those large US brands (Starbucks and Green Mountain in particular) travel directly into Indonesia to "pre-purchase" vast quantities of current and future crops, in effect buying up forward volumes.
Naturally, prices rise whenever there is a shortfall of supply against an increased level of demand.
So why are the US coffee companies buying up Sumatran coffees?
They love using Sumatran coffees because many US coffee companies tend to roast them to "almost death" or very dark.
Sumatrans can indeed take plenty of heat; they need and love lots of heat during the roasting process.
At darker roast levels, the margins for error with Sumatrans are lower compared to many other origins that will fry up or char, hence why the US companies love them because it's almost a coffee that needs little or no talent in the roasting department.
Sumatran coffees are quite intense, typically ranked high in terms of strong flavours, acidity and complexity.
They punch well above their weight, and generally, the roaster seeking a "strong or bold" cup prefers to play with Sumatrans as it's like a "turbo" boost.
After many consecutive years of shortfall in supply and with increased US demand, prices remained consistently higher compared to other origins, a reason they always commanded high premiums in the market, regardless of cup quality.
The other important point to note about Sumatrans is the high risk of cup shame due to the unique and distinctive process used by Sumatran coffee farmers called "wet hulling".
No other coffee origin uses this technique. It's exclusive to Sumatra.
Small family farms process the coffee in highly manual ways, beating the coffee pulp with sticks in tubs.
This process has far greater challenges in controlling the end product quality as most Sumatran coffee farmers often need more basic infrastructure to protect and manage the processing cycle, even just simple sheds or warehouses.
Sumatran coffees are often dried uncovered on tarps, making them vulnerable to rain and affecting final quality.
The wet hulling process also retains much more moisture in the coffee beans, so carefully drying and handling the processed raw coffee is important.
If coffee is not stored properly, it can develop mould and musty taints, making Sumatran lots a risky purchase.
Due to the limited availability of well-controlled storage options, the coffee is often stored in humid conditions, resulting in high moisture levels, causing the coffee to "sweat", especially if packed with liners.
Paying high prices and discovering defects or taints will only end in tears, and it's fair to say that most long-established roasters will have had at least one or more disappointing and frustrating experiences with Sumatrans that are "off".
But it's not all bad news.
Sumatrans are both complex and interesting.
They provide something exciting and not found in other coffee origins, and they certainly have that X-Factor.
It's also not unusual for the cup to change from day to day and from bag to bag when roasting coffee from the same "lot".
Sumatran coffees require a long period from roasting to develop - up to 2 weeks. If you attempt to drink Sumatran coffees when they are just a few days old, you will likely experience an unpleasant brew and incorrectly assume it's defective or tastes herbal.
Yes, that's right, they go bad before turning good, and time is important to rest and develop.
Sumatrans generate amazing flavours and a bold cup.
Over a decade ago, most coffee roasters used Sumatrans to supercharge intensity. Still, with high costs, scarcity and significant risks of unknown defects (or quality and consistency), it has turned many roasters away from Sumatrans.
It's only been recently that the high pricing of Sumatrans has eased down a little - but they are still expensive relative to other origins.
Our understanding for the slight price drops is that it has been due to lower demands from the large US roasters as a direct impact of COVID during 2020, so with a bit more supply from softer US demand, prices have flattened a bit.
Australian coffee drinkers increasingly seek sweeter, cleaner and lighter experiences, which is at odds with Sumatrans's bold, complex, funky intensity.
With many roasters having dropped Sumatrans from their portfolio because of cost-sourcing difficulty, we expect a resurgence in the short term.
Sumatran tend to overpower in blends. Even when used for less than 30%, the Sumatran may hide the delicate features of other origins, so a careful blend design is needed to ensure the result is balanced and complimentary.
Not everything in the coffee universe needs to subscribe to the same playbook of sweet, clean and smooth, and it's the reason we will continue to support and feature Sumatran coffees in our store so that enthusiasts can indulge and discover some of the rewarding secrets of this unique and distinctive origin.