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Hard Beans, Green Beans and Making Coffee Science Accessible to the Community

What makes the speciality coffee scene so fun yet frustrating (all at once) is the newness of it. 

Compared to it’s cousin, the fine wine industry, speciality coffee is definitely the baby of the family. Only in the past 30 years or so have we seen the market break into popular culture. In this short time, the number of people interested in buying something other than straight dark roast at the supermarket has grown rapidly. 

Now, people are far more curious about their coffee – people want to know about roast profiles, tasting notes and origin countries. With this interest, comes far more of a reason to invest finances in perfecting the process, and paying finer beans the respect that they deserve. 

Krzysztof Barabosz brewing coffee at Hard Beans roastery space in Opole, Poland.

Hard Beans is an innovative company at the very forefront of all these developments. This Polish roastery is responsible for a huge number of game-changing pieces of research, which have given producers of speciality coffee a far greater knowledge of how their processes can be improved. In this article, we’ll be delving into one such piece of research that is coming into its very final stages. 

We spoke to Krzysztof Barabosz, the Head of Coffee at Hard Beans, about the roastery’s research into the green coffee storage. Once the project successfully received EU funding, the project was able to take on a whole new level of scope and detail. 

In our discussion, Krzysztof broke down the steps that the team have taken, gave us a sneak peek into their results, and spoke about what their results could mean for speciality roasters across the globe.  

Green coffee samples, ready to be evaluated.

Why is the storage of green coffee important?

Krzysztof said that Hard Beans started by considering the coffee industry on a broader scale, before considering what gaps there were in the knowledge of the processes, or any areas where potential miscalculations influenced the methods that were being used. 

“We were thinking, what innovation or improvement in production can be done, and what research can be done to gain some new knowledge? And, while building the roastery, there was no good information out there that detailed the best temperature or what the best conditions to store green coffee at the roastery.”

The vast majority of the time, when you visit a small speciality or craft roastery, the coffee bags are lying on the pallets near the roasting machine. This is done this way simply for the sake of convenience. No real thought has been previously put into how this may impact the coffee. The bags have simply been placed there so that the roaster can get the coffee from the bag quickly, ready for roasting. 

There is currently no widely-accessible knowledge amongst the independent coffee community about whether or not this practice was influencing the coffee beans. So, the Hard Beans thought that it would be worth checking this out. Not to leave you on a cliff-hanger, but the results were pretty shocking. 

Green Coffee Research funded by the European Union

Starting such a large-scale research project was not something that Hard Beans could have undertaken on their own, without financial backing. The green coffee storage research task that they envisioned required hundreds of hours’ worth of intensive labour, data gathering and then data compiling. As such, this kind of data is something that normally only massive global corporations can possess. And, because this knowledge is so valuable, unsurprisingly, they’re highly reluctant to share it. 

This – both the importance of the knowledge and the difficulty for the world’s independent roasteries to access it – is how the team convinced the EU that speciality coffee was worth investing into. 

Green coffee samples stored for the study.

The funding application process involved writing up the proposed project. The final paper was over 150 pages long, and it took half a year to complete. This involved a huge amount of explanation, covering not only why they wanted to know what the best temperature would be to store green coffee, but also the basics of what speciality coffee is and why it is important. 

“Writing the project for funding wasn’t easy because still, for many assessors of the project, coffee was seen as ‘just coffee’. They believed that there is nothing special about it, so why would you need to make improvements in coffee? They didn’t understand that there is speciality coffee, which is more expensive, more transparent, and very delicate, which means that it is constantly losing its quality with time, depending on how the coffee is stored.”

When it came to writing up the proposal, one thing that proved to be especially useful was the fact that one of the roastery’s co-owning companies is an organisation which specialises in gaining funding for EU projects. With the support and advice of this company, Hard Beans submitted a proposal to the EU which was successfully accepted.  

“The EU funding gave us as a company a far faster speed of growth. Starting out this big and so fast would not have been possible without additional funding.” 

What research methods have you used for this project?

The first step was to build a warehouse, which contained a number of storage rooms, each one with different storage conditions. 

One chamber was set at minus 10°C, the second chamber had a temperature of 5°C, the third chamber a temperature of 10°C, the fourth chamber was kept at 20°C, and so on. Across all of the chambers, the relative humidity was kept at the same consistent level. For example, the minus 10°C chamber was set at around 35-40%. 

Green coffee storage with temperate and humidity controlled environment.

In total, there were six measuring spaces. Within these facilities, the team stored the green coffee and tracked its relative deterioration over time. The chosen coffee was from Guatemala from the Huehuetenango region. The washed variety was caturra, the processed came from Finca La Maravilla and the natural from  Finca El Oregano. It was packed in small GrainPro bags and Jute bags.

After building the warehouse, the Hard Beans team enlisted the support of Łukasiewicz Research Network-Institut of Heavy Organic Synthesis “Blachownia”. This institute undertook all of the chemical and physical measurements that were required for the experiment. 

Another laboratory from Warsaw that was heavily involved in the green beans project was JARS S.A. The help of these institutions was vital as, between them, the team of researchers were measuring over 20 different parameters of the coffee beans. This included measurements of a wide variety of the coffee’s composition, including its volatile compounds, chlorogenic acids, acrylamide and caffeine content. 

These chemical measurements were made every month. In addition to this, a sensory summit took place once every three months. In attendance at these summits were Q Arabica Graders in Poland, the SCA AST’s, and sensory skills professionals from SCA certificates. In order to ensure complete accuracy at the sensory summits, a minimum of five judges were required to make the assessment. All of these samples were cupped as double blind, triple coded samples at the cupping tables.

Testing over 600 individual green coffee samples

In total, between 600 and 700 samples were stored in the chambers in this warehouse. Every month, a sample was taken from the chamber, roasted using a ROEST sample roaster and, after roasting, both roasted and green samples were shipped to the Institute of Heavy Organic Synthetics and JARS S.A.

The coffee was split into six chambers, meaning six different climate zones with two types of coffee, different varieties of storage bags, and coffee that experienced two different processing methods (natural and washed) in each. So, this gave the team a total of 24 samples. 

Then, a double-blind assessment was required on the cupping tables, (which brought the number up to 48 cups of coffee to sample). And then, every sample was present on the table three times. So, in order to judge two different types of coffee, 144 cups needed to be judged. 

On 10-11 December 2020, the final sensory summit and assessment by the judges took place. 

This is the biggest project that the Hard Beans team are currently involved in. Now that the last report has been completed, the team will need to cover all of the data that has been gained over the entire two year period. It’s no mean feat. 

Is freezing green coffee beans the best storage method?

Already, before the data has been fully processed, the team can see some changes in the different coffees, which have arisen as a result of their storage conditions. 

One of the most interesting results from this experiment concerned the potential of freezing green coffee beans. 

At the very start of this project, the team’s original thesis was that freezing coffee should be the best option. However, they soon found that this method did not work for green coffee. This is due to the water content inside the green coffee. 

Although you can freeze roasted coffee very successfully, the water content in green coffee is far higher than that of roasted coffee. So what was witnessed when green coffee was frozen was a change of state within the bean’s liquid components into a solid state, and then back again to a liquid state. 

This dramatic structural transition changed the structure of the coffee considerably. That’s why freezing the coffee did not provide the best results, both in terms of retaining its chemistry and its score on the cupping table. 

The other key area of research that this project has focused on is the impact that each chamber has on the coffee’s freshness. By doing this, the aim is to identify the optimum storage conditions for green coffee beans. 

‘The last measurement was done in December 2020, and now we see the correlation between the chemical results and the sensory results. We now know which chamber keeps the beans fresher for longer. We also know what the best parameters are to store the coffee at the roastery, and how important it is to store it in a cool space. 

‘When you store coffee in a hot space, what can I say? The fastest degrading chamber was set at 20°C. And the coffee was like falling apart, it scored around minus four points in December 2019, just four months into the project. So it’s losing its quality very fast at that temperature. In fact, on the final sensory assessmentassesment the 20°C chamber lost by a significant margin on every single table, in some instances scoring as low as 73 points.’ 

When can we read the results of the study?

In typical 2020 fashion, ‘Everything depends on COVID now.’

When the project finishes and the data has been collected, the team will be able to bring about the goal that has formed the cornerstone of this project right from the outset. 

‘We as a company we need to share the results publically, for free.’ 

Now that the Hard Beans researchers have ascertained this knowledge – covering not just how to build optimum green coffee storage facilities, but also an understanding of green coffee’s degradation – this will help to transform the day-to-day roastery practices of companies across the globe. This will significantly benefit the quality of the coffee that is produced, and so the success of these indies. 

Hard Beans plans on sharing the results of the project at conferences. It will also be detailed in articles and publications, which will be produced alongside the institutes and universities that were involved in the project. 

These articles will detail each of the different changes and results that were found during the project. But, if you don’t think you can wait till then, Krzysztof has shared a little sneak peak into the results for us. 

‘The one result that I can now share with you is the findings from Łukasiewicz Research Network-Institut of Heavy Organic Synthesis “Blachownia” after their measurements of antioxidant levels in coffee, and how these levels are changing depending on how you store the coffee.’

The results indicated that the conditions that you choose can actively influence the amount of antioxidants that your coffee has. Roasters can successfully promote higher levels of antioxidants in the coffee by choosing to store their coffee in good conditions. Equally, however, if you store your beans in ‘bad’ conditions, the antioxidant levels will drop. 

As we mentioned, this project has taken 2 and a half years. It also involves over 20 people, so it is hardly a surprise that the roastery could never have afforded this kind of project without the funding. 

This otherwise-inaccessible data is information which will hugely benefit independent roasteries operating across the world. And Hard Beans feels as though it is its duty to respect the community’s inherent lean towards collaboration. For Krzysztof, one of the main goals that shaped this project was the concept of sharing these results to better the entire speciality coffee community. 

‘What is amazing in speciality is that there are many theories at play here, but if you ask for data, numbers or any proof, you cannot find it. Or you cannot find any good proof, at least – you’ll almost always just get the answer ‘I do not know’, cause it has always just come from word-of-mouth advice. What’s the actual data behind these practices?’ 

‘So that’s our goal – to make clear coffee statements that we have a proof for and have data to back up. This kind of project is giving us proof.’ If this glimpse into the work of Hard Beans has successfully piqued your curiosity, you can find out more about this exciting upcoming project on the Hard Beans website.