What Role Can Machinery Play in Specialty Coffee Processing?

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Sometimes, it’s hard to separate the concept of specialty coffee from something artisanal and small-scale. It’s the human knowledge and care, we think, that produces some of the world’s best coffees. It’s human hands, not machines.

And there is no denying that human hands are indispensable for quality coffee. Yet if machinery can assist them in producing consistent specialty coffee and perhaps even increase the quality, why not take advantage of every tool we have available to us?

To discover more about the role that machinery can play in specialty coffee processing, I spoke to experts from Ipanema Coffees, a Brazilian group of farms, as well as some of their partners.

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The cupping lab at Fazenda Rio Verde, Minas Gerais, Brazil, where an average of 200,000 coffee samples are cupped every year. Credit: Ipanema Coffees

Which Machines Can Be Used For Harvesting & Processing?

Let’s evaluate the process from the coffee tree to the bag.

1. Harvesting

Coffee cherries are harvested from the coffee trees, a step that can be done manually or mechanically.

Christiano Borges, Ipanema Coffees’ COO, tells me that the highest-quality coffees come from the perfectly ripe cherries. “Harvesting perfectly ripe cherries is nearly impossible, or very expensive,” he tells me.

Large-scale producers in countries like Brazil often use mechanical harvesters, while small-scale producers working with uneven ground tend to harvest by hand. The challenge, when using machinery, is to control the ripeness of the harvest.

When harvesting by hand, producers can select only ripe cherries, leaving the under-ripe ones on the tree to be harvested later. They can also discard over-ripe or defective ones. (However, not all small-scale producers do this. Some use strip-picking, a faster method that involves placing their hand around the base of the branch and tugging along the length. In doing so, they pull all the cherries, leaves, and small branches off at the same time. This method tends to be favored by commodity-grade producers.)

When harvesting with machines, producers are unable to inspect the cherries in the same way. They can, however, carefully pick the day on which they harvest their crop so as to ensure the highest-possible percentage of ripe cherries. Some producers also harvest different lots on different days.

The use of machinery doesn’t mean that these producers can’t work toward specialty coffee, however. They just have to then invest more time into sorting their harvest. Producers must ask themselves which is most efficient: reducing the labor during the harvesting, so that they can pick their coffee more quickly, or reducing the number of discarded cherries during sorting. Often, this is a matter of farm size and economies of scale.

Coffee is harvested mechanically at Ipanema Coffees. Credit: Ipanema Coffees

2. The Wet Mill

Eduardo Tassinari is the Agricultural Director at Ipanema Coffees. He talks me through their methods. “After the coffee arrives from the crop, it first passes through a washing process. The washer is actually a separator… The lighter coffee fruits float in the water… the green beans and ripe cherries sink and go to another machine.”

But that’s not the only machinery that Ipanema Coffees use at the wet mill. In 2012, they launched their Premiere Cru program on Fazenda Rio Verde in Mantiqueira de Minas, a mountainous region in Minas Gerais. The goal was to produce a large portfolio of specialty coffees and micro lots with varied flavor notes. But to do on a large scale, without sacrificing quality or consistency, they decided to turn to machinery.

They partnered with Colombian coffee machine manufacturer JM Estrada to develop wet and dry mill equipment adapted to Brazilian conditions. They also worked with the Spanish corporation MultiScan to adapt a machine originally developed for separating fresh olives by color for use with coffee.

Christiano tells me, “The machines have basically two main objectives: one is the selection, which means the separation of the beans, with the aim to select the best beans… in terms of ripeness, physical attributes, size, weight, and color. And the second main objective is basically to dry the coffee.”

When working with specialty coffee, it’s important to ensure you are working with the best possible quality cherries. On small farms, this is often done by hand. Teams of workers will manually inspect cherries at every stage, classifying them by quality and removing any that don’t meet standards.

Yet when working with large quantities of coffee, machines can help humans manage the work without errors.

Machine sorting can also be particularly useful for certain lots. Christiano says, “We know the exact potential of each area and we are able to prioritize areas according to their potential… which includes setting up the equipment and processes to get the best from each area.”

Luis Guillermo, Director of Design at JM Estrada, tells me, “I think the machinery plays an important role with high quality during processing coffee, because of the control after post-harvest coffee will be supported by the high technology of the machinery.

“The quality of the coffee depends on good management in the farm, and high technology for processing coffee in post-harvesting.”

3. Processing

At this point, natural processed coffees go directly to the drying phase. However, for washed/wet and pulped natural coffees, the process is different.

“The second piece of equipment is the husk remover,” Eduardo tells me. This, he explains, removes the husk by friction. However, since under-ripe cherries have a harder husk, only ripe cherries are peeled. The unpeeled, green ones are kept for the internal consumer market, ensuring that there is no waste.

Those “peeled” cherries are dried as pulped naturals, Eduardo explains, while washed processed coffees go to the fermentation tanks so that all of the fruit can be removed. Careful monitoring ensures the fermentation is controlled and consistent.

Aerial view of the drying station of Fazenda Rio Verde. Photo credit: Ipanema Coffees

4. The Drying Stage

Poor drying can let down excellent harvesting and processing. Too much moisture for too long can lead to mould, uncontrolled fermentation, and uneven flavours – not to mention dissatisfied roasters, if they find that lots contain more moisture than expected. After all, they’re paying by weight, and water isn’t light.

Coffee beans can be dried mechanically, in greenhouses, or under the sun. If not dried mechanically, they can be dried on patios or on raised beds.

Eduardo tells me that a slower drying phase is key for coffee quality but that, depending on the type of coffee being processed, a mixture of the above methods might be best.

It’s also important to consider the local climate and conditions. There are times when drying may need to be sped up in order to avoid the development of mold or uncontrolled fermentation, especially when the atmosphere is humid or the beans are drying in their pulp.

Rodrigo Rodrigues, Industrial Director at Ipanema Coffees, agrees. He tells me, “Yes, there are traditional techniques that are still in use. Let me give you an example: a naturally, 100% sun-dried, coffee. It’s something that we still sometimes do in processing…

“It is possible to produce good coffees with traditional methods, but it takes a lot of time… And you start to take a lot of risks. If you are drying 100% on patios, the patio is exposed to the sun, rain, humidity… So, can you do it? Yes, you can, but it’s very hard.”

For this reason, when working on a larger scale, he prefers to mix methods. Most of their Ipanema Coffees’ lots start off being sun-dried to get that slow drying. However, the process is then finished in machines in order to have more precise control of the temperature and moisture content.

Vertical Mechanical Dryers at Fazenda Rio Verde, Minas Gerais, Brazil. Credit: Ipanema Coffees

4. Resting, Parchment Removal, & Grading

Eduardo tells me, “After the coffee has been dried, it goes to a silo for resting… There, it is stored for at least 30 days, sometimes longer… and then it goes to the dry mill.”

It’s here that, at Ipanema Coffees, the parchment is removed by a machine and screens are used to grade the beans by size.

But What About The Human Factor?

No matter how good the machinery, it cannot produce quality coffee if it is not used well.

Rodrigo tells me, “In the first year that we worked [with the new equipment], we were in constant contact with a machine technician so that we could, by analyzing our process and understanding the capacity of the machines, try to get the best out of them… I would say that they are excellent pieces of equipment but, if they are poorly calibrated…, you will get very bad results.”

Sometimes, a machine can be calibrated well – but only for one type of coffee. “One of the first machines on the wet line is the pre-cleaning machines,” Rodrigo says, explaining that they “are responsible for removing all impurities from the coffee, which may be coming from the field, from the harvest. They strip leaves, sticks, dirt, impurities…”

Used appropriately, a machine like this can help strengthen relationships with roasters. Stephen Hurst, the Managing Director and Founder of Mercanta, a coffee supplier based in the UK, tells me, “A small, seemingly minor issue, like small pebbles or stones, pieces of metal… is not the biggest deal for larger roasters with de-stoners at the roastery. But for many of our clients, such poor preparation is a disaster, a nightmare.

“The stones get roasted and packaged and break the blades of grinders within cafés. This poor example of preparation leads to no end of problems in our world. So, measures to prepare specialty coffees with near-zero defects, colour sorted, highly selected are indeed very important.”

He adds, “We have honestly hundreds of potential Brazil suppliers, even in our small, specialized niche. We are spoiled for choice from whom to buy. So, factors such as Ipanema’s visible and significant investment in the new facilities at Rio Verde are not only very impressive, but they help ‘tip the scales’ when so many other things are equal.”

Yet it’s not enough for producers to invest in this machinery. It’s important that they also understand how to calibrate it. “These machines are very efficient,” Rodrigo continues, “but the airflow is adjustable and so is a flow that we call ‘vibration,’ which helps to remove these impurities. So, if I put a very dirty coffee with a lot of foreign objects, I need to adjust the machine. If I have a coffee with few foreign objects, I have to do another adjustment.”

It requires human expertise to understand exactly what each coffee lot needs – and then to assure it receives that.

Stephen Hurst, Founder of Mercanta, and Washington Rodrigues, CEO of Ipanema Coffees, at Fazenda Rio Verde, Minas Gerais, Brazil. Credit: Stephen Hurst

Different Circumstances, Different Solutions

It’s not just the different coffee lots that require different treatment. Each coffee-producing region in the world has its own unique climate and production culture, which will determine how the coffee is handled in the farms and mills.

Luis worked on adapting Colombian machinery so that it could be used on Brazilian farms when he partnered with Ipanema Coffees. He tells me that he had to do a lot of research into coffee processing in Brazil – and that Ipanema Coffees also researched Colombian methods so that they better understood the impact of the machinery.

He tells me, “Our machinery was adapted for increasing the efficiency of selection and to achieve a better selection on Rio Verde Farm than in Colombia… this is because, in Colombia, the process is for small farmers, and [for] Rio Verde Farm, the machinery was adapted for processing high quantities of coffee at a high quality.”

There are also other factors that can affect the ideal harvesting and processing method. Steeper inclines can make it harder to use harvesting equipment, as can coffee trees that are planted close together or not in rows.

Coffee processing equipment is not a plug-and-play device. It’s important that producers understand exactly what it is designed to achieve and how best to apply it for their particular farm and coffee.

Depulped washed coffees and natural coffees still in the pulp. Credit: Ipanema Coffees

Andrey Savinov is the General Director of SFT Trading, a Russian green coffee supplier established in Moscow. He says, “For years, we grew accustomed to the idea that a micro lot is to a large extent the baby of nature. One year, it may appear on a particular farm. However, it may easily disappear next year. Ipanema Coffee’s Rio Verde project is contrary to that. I call it a ‘micro lots factory.’”

He has been purchasing coffee from Ipanema Coffees for 14 years and says that their use of machinery is part of the reason he is able to do so. It ensures that coffees are of the same quality and cup profile year after year.

Ultimately, machinery offers consistency and efficiency – when used well. On the opposite side of this is the risk of uniformity, not in coffee quality, but in production methods. The key remains understanding the coffee, the farm, and the market, down to the exact lot. It is the combination of human hands and technology that ensures quality remains high.

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