From the Fruit to the Cup – Part III
PART III – Hulling and Roasting
Many of us quickly categorise our cups of coffee as either ‘good’ or ‘bad’. In truth, even the best made coffee has a staggering amount of variability based on region, growing conditions, processing techniques, roasting recipe and blend. In my previous article – From the Fruit to the Cup, Part II – I looked at how coffee is picked in the Tri Karya subak of Gitgit, Bali, and how their wet processing techniques are used to extract the bean from its fruit. This article will pick up from the point that the green beans arrive at their destination: the wholesaler, who will transform the processed green into a roasted and packaged single origin or blend, ready to be sold to a café or other supplier.
In order to learn more about the roasting process, our group travelled to the mountainous region of Ulian, subak of Kintamani, about 2 hours drive from our home base in Kalibukbuk, Lovina. The previous year, Five Senses had commissioned an Indonesian manufacturer to build a roaster and have it dropped off at a farm in Ulian. Here, the locals were using older roasting techniques, which can sometimes be as simple as roasting beans in a wok over a cooking fire. This new roaster promised to cut down roasting times to as little as 20 minutes, while also drastically increasing roast batch sizes, transforming their subak into a co-op capable of selling directly to Bali cafés and shops.
We arrived to find the roaster in pieces and gathering dust in an otherwise empty hall. Our group leader, Shaughan, had purchased 2 motors from a workshop in Singaraja the day before, which were to be fitted to different sections of the roaster in order to make it operational. As with the wet processing at Tri Karya the day before, it was important that most of the work be completed by, or at the very least watched by, the local farmers so that they would be able to use this knowledge once our group had left.
On the wall of the farm’s dining hall was a large chart keeping track of stock owned by different members of the subak, a remnant from the French who had attempted to unite the Kintamani region under a single brand in order to achieve name recognition similar to that of Bordeaux or Champagne. Unfortunately, when the French left the Kintamani region, farmers did not keep up the practices they had learned (either due to a lack of knowledge or a lack of interest), and so the quality of coffee exports dropped. The chart had not been touched since 2010. It is important that knowledge imparted be used and not left to gather dust, and so we wanted to make sure the benefits of what we were doing could be easily noticed.
Once the motors were fitted to the roaster, we connected the various pieces of machinery and fitted the gas bottle. Most quality roasters in Australia have a self-ignition system, but being a rather cheap model, this one required manual lighting. The Ulian farmers brought us a bag of green beans, and we decided to test out the roaster by roasting 2 batches of 5kg.
A roasting operation will sometimes receive bags of green beans with a hull, called the ‘parchment’, still on the bean. This is a papery husk that needs to be removed prior to roasting, and which accounts for roughly 16% of the weight of the bean. A further 16% of weight will be lost in moisture during roasting. A piece of equipment very similar to a pulper is used to remove the parchment from the bean, after which it is ready to be sorted for any further defects. Like all previous processing phases, consistency is the key to a good roast – therefore, any leftover parchment, small or deformed beans, or miscellaneous debris must be removed.
We had 2 expert roasters, Nathan and Tom, with us to run us through the basics and perform the test roasts. They were also there to show the farmers the ropes, and help them write down any safety information or processes they would need to remember to complete their own roasts. Different coffee types require different roasting times and temperatures, but we used an espresso roast as a rough guide and aimed for a starting temperate of 200 degrees celsius, and a roast time of 15-16 minutes.
After the beans are fed into a hot roaster, it is important that the temperature never goes backwards. This will affect the chemical reactions in the beans and produce an undesirable result. The beans will gradually turn from green to yellow to brown, with consistency again being key – the closer the beans are to each other in colour, the less variation in the batch and the better it will be. Roasters are able to bring out different flavours in the bean by changing the temperature and time of the roast, and this can be a very difficult process to master. Most roasting machines have a window and a sort of shovel for sampling the beans as they are roasted, giving the roasters a way to monitor the batch and decide when it is ready.
When the roast is finished, the beans are dropped into a large cooling bin, or vat, which draws hot air down through the base and out an exhaust, while also using slow spinning arms to keep the hot beans moving around. By doing so, the cooling process is expedited, stopping the beans from continuing to cook due to the exchange of heat between beans. Once the beans are sufficiently cooled, they are spread out and then dropped again into some sort of receptacle, ready to be transported and packaged for wholesaling.
This roaster, despite being considerably less robust than most expensive Italian-made machines many Australian roasters would use, worked fairly well. Both expert roasters seemed fairly satisfied with the end result, though both stopped short of suggesting it would be anywhere near saleable in Australia. Australian wholesalers, and their customers, demand absolute consistency and excellence from their beans, which in turn demands a high level of knowledge and consistency in every process from picking through to roasting. Though Balinese people have been growing coffee for years, only recently have farming practices begun to increase in sophistication, and the level of local knowledge is still developing.
Through the picking and processing stages, right up to the roasting, we have seen how necessary it is to be careful with quality. There are a staggering number of variables which can be altered at any step of the chain, which would negatively affect the final quality of the coffee batch. Even assuming perfection up to the point of sale from wholesaler to café, there are still many more techniques that must be correctly executed, lest the resulting cup of coffee be a complete waste of everyone’s time, effort, money and knowledge.
For these reasons, most cafés use a specific recipe for their espresso shots which should be followed exactly. Here is the one we use at Moana Coffee: every dose of ground coffee should weigh approximately 20g, and be tamped evenly into the coffee machine portafilter. The correct volume of water must be passed through the coffee, and at the correct temperature and pressure. Finally, the coffee should be extracted for only a precise length of time – somewhere between 27 and 31 seconds, usually – lest the shot be either under or over-extracted, therefore failing to bring out the desired flavours or, even worse, producing the dreaded ‘burnt’ taste we all associate with bad coffee. An unskilled or distracted barista can undo all of the hard work of the farmers and wholesalers who have perfected their art.
On the flip-side, it should also be remembered that there is so much knowledge out there in the world, as well as a huge number of people who are committed to getting better, and achieving excellence. Next time you receive a truly memorable coffee, thank not only your barista, but also give mental props to all of those hard-working people along the way who transformed the humble coffee fruit into your little moment living the delicious, caffeine-filled dream.
Part IV will conclude this series, and will take a look at what happens when we leave the farmers to carry on farming with the techniques and processes they have learned.
Andy owns a Perth café and is the Creative Director of FLINT Magazine.