Green Light – Grain Pro

Seasonality has become a key aspect of speciality coffee and part of what distinguishes it from commodity coffee, of course this sits alongside the most important difference, which is that of flavour. Traceability and provenance are tied up with the seasonality factor, but one of the main reasons for focusing on coffee as a seasonal product was the way past crop tastes. The coffees would lose all of their positive acidity and often much of their wonderful character, on top of this they would develop baggy, musty and generally nasty flavour.

The time frame for this degradation was not set in stone, with some coffees dropping off of a flavour cliff very quickly, just a matter of months from arrival in the country, which depending on the country, processing and shipping would have been around a further 3 months form picking the cherries. Because of the almost two half’s of coffee production throughout the year (latitude driven, with north of the equator harvesting throughout our summer months and south of the equator harvesting throughout our winter months) It was tempting to stick to each half for roughly six months of the year, effectively splitting the year into two coffee seasons for consumers of speciality coffee. Of course there are fly crops and countries that have less strict cropping seasons but this was a good general rule. There was the odd coffee from Ethiopia that tasted amazing for longer than it should and so forth, but the last couple of years have seen a change.

At this moment in time I am tasting Guatemalan coffees that taste, vibrant and fresh, coffees that were harvested nearly 12 months ago. And, Its not just that the coffees are from Guatemala. Theres a common theme. Grain pro.

Traditional Jute/Hessian sacks have been the carrier for green coffee for so long that they have become synonymous with the bean, a symbol of the exoticness of the ingredient. However, Jute packagings alluring prettiness hides massive failings as a packaging material for an agronomical product that suffers easily from tainting and degradation.

Grain pro is a type of packaging used to store green coffee from when its harvested through to sitting in a roastery waiting to be dropped into a hot spinning drum. It is increasingly becoming the packaging of choice in the speciality industry. Grain pro is effectively a plastic bag of sorts that is billed as creating a hermetically sealed environment. In practice it is rarely completely sealed, especially the non zip tie option, which ends up looking like a shopping bag tied into a knot at the top. There are also other options on the market, with Vac packed being the most notable. This differs in that it is completely sealed and all of the air is removed from the pack leaving you with a brick of coffee. Vac packing is a requirement for cup of excellence coffees’. Vacuum packing is however considerably more expensive than grain pro and currently is limited to smaller lots of more expensive coffees.

What’s staggering though, is the leap in quality from Jute to grain pro as coffees are stored for longer periods of time. Of course it still has to be good coffee that was well processed in the first place, and yes there are still exceptions, with coffees that drop off relatively quickly even when well stored.

All in all though, this move to grain pro is a very good thing. It does not mean that speciality coffee will become less unique or less seasonal. Lots of coffee from interesting farms will still go within relatively short periods of time after harvest, speciality roasters will still be excited to get hold, taste and sell the freshest and best coffees

It is effectively a great piece of development within the coffee chain that reflects an emphasis on and a regard for flavour in coffee.Its a difference that can be tasted and seen at a consumer level. It means roasters and importers can make more of the coffees they buy. After all its no problem to explain to my customers that the time periods from harvest and the loss of flavour that makes the coffee speciality is not as short as it once was. We will still only be buying and serving the coffee based on how it tastes.


Comments Off

Filed under Uncategorized

The Difference – Sourness & Acidity

As mentioned in the last post, we are currently working on a water project that will become a little book. Part of that process is the inspiration for this article. During the project we organised blind taste testing sessions, and we drew up our own scoring sheet for participants to use. We did this in order to split up a few specific sections and try to achieve more objective and quantifiable results in relation to the tests we were doing.

Below is a link to one of the graphs that displays the sensory results of one coffee blind scored across three different waters – A, B and C.

Before testing began, I instructed the tasters to mark acidity in terms of how positive it was, i.e. that if the coffee has a lot of desirable acidity then mark high and to mark low for vice versa, for sourness I told them to mark this section in terms of intensity, low for little to no sourness and high for very sour

Coffee1_A,B,C (2)

As you can see, tasters responded quite differently to the same coffee when made with different waters, but what is of particular interest here, is the comparison between the sour and acidity columns for each water.

I think that the more useful and relevant the language when assessing and describing flavour experiences, the better. Often this just means using two terms rather than one, so they can complement and contrast each other. In essence two assessments are needed when one piece of terminology won’t do the job. I think “acidity” and “sourness” are a prime example of this.

A common statement is as follows – “sourness IS acidity”

When marking acidity on coffee we are not marking the sourness of the coffee, even though types of acidity can contribute to sourness. We are instead marking a quality that (if one is not familiar with as regards speciality coffee) could be misinterpreted as denoting sourness.
Although it’s possible for a coffee to have high acidity and also be sour, this doesn’t mean they are mutually exclusive. For instance, a creamy, nutty and floral coffee could have wonderful acidity; acidity that may be crisp, juicy, or sparkling. Here the coffee does not display much sourness but has great acidity.

This may sound a bit obvious but I think it’s worthy of a little exploration and this graph and the taste test we did were, I think, a good direct example of this topic rather than my more philosophical ramblings on the same topics in blogs such as – ‘Why Coffee Isn’t Overly Acidic’ (In hindsight, the wording ” Isn’t Overly Sour and Acidic” would have been a more accurate title) and “taste, flavour and perception”.

If you study the sourness and acidity results, they actually display the most opposing results out of all the sections. In that water B has the best acidity, closely followed by water A, but when we then move over to the sourness column, water B displays almost half the sourness score that A does.

This means that water A, although displaying a high, positive acidity also displayed high sourness; whereas Water B wins out on acidity but is accompanied by much less sourness. When we consider the other scoring sections we can deduce that water A brewed/produced a cup with good acidity but was also quite a sour driven cup. Whereas water B brewed/produced high/good acidity along with a more balanced and complex cup.

The breaking up of sourness and acidity was particularly useful for this test, if we only used acidity to mark the coffee, then A and B would have appeared closer in this area, but the sourness marker shows how different they really were.

It’s useful to also note that water C displayed abysmal acidity but comparable sourness to water B. This can then help infer that water C most likely displayed a dull heavy sourness, with little desirable acidity.

I find the interplay of these two markers fascinating as they rarely seem to match up and together I think they’ve told us more about what people were tasting on the day and how exactly the waters affected the same coffee. I wanted to share this graph as I think it nicely displays the independence of acidity and sourness in coffee.


Comments Off

Filed under Uncategorized

What About the Water?

Having been preoccupied with this question, its been a little while since I’ve written a post.

Water is naturally a huge part of a cup of coffee and the more and more we look at it the more it presents itself as one of the biggest players in a cup of coffees’ flavour.

We choose our coffees carefully, buying from roasters whose coffees we enjoy. On occasion we have really struggled with a few coffees. In these instances the coffees were not just a little flat or uninspiring, but were actively unpleasant.

The roasters we work with have always been receptive to feedback and keen to take part in a coffee dialogue, in the very rare instances when the coffees have been actively unpleasant, we’ve reached a difficult half way house where they are happy with the sample when brewed at the roastery, with there not seeming to be any of the same problems. In fact on these occasions they sound like different coffees altogether. After tasting coffee with them and trusting their judgment as they do ours, we were each taking part in a Sherlock-esque like hunt to find the culprit behind the nasty flavour transformation.

The increased ability to communicate about what and how we (any of us) are brewing, through the use of more exacting measurements, means it has become easier to rule out many parameters as the cause.

More often than not the clues lead to the same end – different water.

Can the water really be responsible for such a dramatic difference?

How often has the magnifying glass really been put on water? Sources such as the SCAA water book shed some light on the topic and we are all led to focus heavily on TDS (Total Dissolved Solids) as the measurement we should concern ourselves with, indicating that it is what has the biggest impact.

But what is TDS? A broad and vague measurement that indicates the total amount of minerals and particulates in the water beyond the pure H20. A brief look of bottled water labels will display that the number (TDS) can consist of largely different proportions across varying brands.

Would two waters with the same TDS, one in London and one in Bath, be the same? Would they impact on the coffee in the same way? What about the other numbers?

To explore these questions we were lucky enough to be able to enlist the help of theoretical chemist Christopher H Hendon. Chris has worked on varying projects with some focusing on taste products such as wine. He showed a keen interest in exploring water and coffee with us.

The resulting work has been fascinating and rewarding, with studies ranging from the use of atomic absorption spectroscopy, through to making the most of the U.K.’s largest super computer, as well as large blind taste testing data collection.

In order to fully present our piece on water and coffee, we need a different format to this blog. We are currently compiling an Ebook that will be released in the near future, I will make a note on this blog when the Ebook is released.

Comments Off

Filed under Uncategorized


Let me describe a manifesto of sorts regarding speciality coffee; a statement of intent.

- To bring together peoples involved in speciality coffee, from across different cultural, economic and experiential backgrounds and to unite them with a common language of communication as well as more united reference points for quality and grading. Achieving and improving these aspects of world wide coffee, from producers to consumers, has the potential to benefit all of those involved -

This statement is of my own hand, yet it is, I believe representative of the epic and admirable ambitions of the Q program.

The Q graders course is a qualification offered and run by the CQI (Coffee Quality Institute). I was recently able to participate in the first Q grading course held in the UK. It was headed up by Tracy Allen with the collaboration of Lynsey Harley and Falcon coffee. The courses are held regularly all around the world, with those wishing to take part making their way to the nearest destination holding the course.

The Q course assesses a student’s knowledge and understanding of speciality coffee (along with commercial coffee references) as well as their ability to assess the sensory qualities and attributes of individual coffees. This naturally also includes a focus on the language and tools needed to communicate about coffees’ quality effectively as well as agreeing on points of reference for coffees’ quality in the first place.

The course is essentially half training and half examination. However, I don’t think it would be at all possible to turn up with no experience and pass. It consists of a total of 22 tests / assessed tasks over a 5 to 6 day period with time allocated for retakes. There is only one written exam in the form of a general knowledge test. The others are all practical and sensory based tasks.

The intent is to assess and provide a student with a holistic understanding of the industry which works towards qualifying them as a coffee professional, with the natural emphasis being that of sensory perception and explanation.

One of the main goals of the Q is to work towards standardising cupping procedure in order to make scoring and assessment more useful across a broader area.

I had done a fair bit of cupping previously, but rarely using an in depth score sheet. The advantages of using a score sheet are plentiful and this is something I definitely took away from the course. By breaking up the scoring into multiple sections, it pushes a more considered and rounded view of each particular coffee. There is an overall section that notes how you feel about the coffee (whether or not you liked it) but the breaking down of the other aspects of the coffee such as acidity, body and fragrance do force you to assess why you may like it and how much of your marking is preference, hopefully helping to develop the most objective and accurate assessments possible.

It’s a great way to log what you thought of a coffee, which then allows you to go back and and remember in substantial depth the assessment you made. It also serves to help people discuss coffees with each other, allowing you to pin-point the discussions. The usual things apply, that the judgments are relative to the origin of the coffee and the company the coffee is a part of, i.e. that the characteristics of one coffee (a big natural) will impact on the next coffee you assess on the table.

In fact a big deal is made of considering each section of the cupping score sheet as something that is relative to origin. For example, coffees’ wont be as evenly uniform and will have a bigger body if from Indonesia. This relativity goes further than origin, into considerations of variety etc. It’s a big, experienced-based conversation that although touched on by the Q, is rooted in a wider experience of speciality coffee.

It’s useful to pit stop on the relativity vs objectivity aspects in assessing coffee. The Q couldn’t exist if coffees’ quality was purely subjective and random. There has to be an objective structure. In fact there is one, it exists, thats how grading exists at all. I’ve touched on this in other posts, but I see the structure of speciality coffee as an objective structure built out of collections of subjective experiences, creating a field which means something objectively in terms of taste and flavour. This was quickly pointed out on the first day of lectures, with one of the aims of the Q being to prove that quality in coffee is not subjective, and that defined standards can especially empower coffee growers.

For the various triangulation tests (picking the odd cup out of tree cups) Tracy offered us the chance to assess all of the ground coffees using smell alone to see if we could pick the odd cup out, without actually cupping them at all. The aim of this was to put an emphasis on the power of the nose as an assessment tool. The pass rate was very high in this test which certainly verifies the ability of our noses even if we weren’t so sure ourselves, with no one having to re take and cup the triangulation coffees in the group.

The hardest test, was as everybody anticipated, the sensory evaluation test. This exam used various strengths of acid, sugar and salt. We first assessed 3 solutions of each(with the acid being citric), consisting of a weak medium and strong version. So far so good, However things get tricky with the main part of the test, which is a collection of solutions that each contain more than one component but not necessarily all three. The task being, to pick out which were in each solution and at what strengths. What makes this test harder than other sensory tests, is not only that the differences are subtle (as when a weak solution is mixed with another weak solution that means each component is then twice as weak) but that knowledge of how they interact with each other is also paramount. For example sour will make sweet appear stronger and salt will make sour appear less strong. These elements need to be considered when deciding how to mark each solution.

Other sensory tests included aroma detection and correlation using the le nez du cafe, as well as acid detection. In the acid detection test various cups of the same coffee are spiked with a low concentrations of different acids. Each spiked cup will only contain one acid at a time. With the task requiring the student to identify which cups have been altered and with which acid.

All students were able to pick the cups out that bore the addition of an acid. But there was far more trouble specifying what each acid was. Acetic acid proved the most easy to identify, displaying the pungency so familiar and distinct. Acetic acid is most commonly tasted in the from of vinegar. Citric (which lends it name to the citrus fruit family, interestingly this is probably the softest acid and is in all coffee) and Malic acid (typical of the sour note in green apples) were both relatively easy to discern at lower concentrations but were confused at higher concentrations. Phosphoric acid was also confused at higher strengths. This acid is unique in that it was the only acid commonly found in coffee that the plant is not capable of producing itself. It must instead be picked up from the soil in which the plant is growing. This acid also presents a sourness at high concentrations but is mostly recognised through the tingling sensation it presents on the tongue. It is common in East African coffees and will be found in abundance in coca cola. Chemically, phosphoric is also a particularly strong acid.

There are other common acids in coffee which were not part of the test such as lactic and Quinic. Quinic is cited as being one of the most common forms of bitterness in coffee, In high concentrations, this acid has proved dangerous to health, and its for this reason that its currently excluded form the course.

The aim of all the sensory tests in the Q is to help each student understand their own strengths and weakness, taste bias if you will. Through this more self aware tasting is achieved, resulting in more informed and useful dialogues between people when considering coffees. Theres also no reason that these tests should not be embarked upon outside of the Q. In the lead up to the course we got a hold of a lot of the materials in order to practice and prepare for the course. Just like the super taster test which was the basis for this perception post, each of the sensory tests proved insightful. They were each, great processes for staff learning and exploration and more often than not customers would take part in various aspects of the tests as well.

Improved understanding of how we each taste and the language we use to communicate to each other can only be beneficial for a field like speciality coffee. Considered tasting and informed discussions about it results in leaps and bounds of not only understanding but also rewarding and fun tasting experiences. This achieves so much more than, the notional “we taste, sense and process flavour differently, which means its all subjective so you can’t talk about it”.

There were also a few tasks that focussed more on visual assessment such as green bean grading and roasted coffee assessment. Green bean classification starts with a 350g sample of a particular coffee. Defects with the beans are broken into primary and secondary categories. In nearly all cases one primary fault, such as a black bean (there are various causes, such as lack of water during cherry development or over fermentation) will disqualify a coffee from being classified as speciality coffee and then be labelled as commodity coffee. There is then a secondary defects conversion chart, so that for example 5 broken/chipped/cut beans equal a full secondary defect and a total of five of these creates one primary defect which disqualifies the coffee again. Obviously this is just a visual assessment and the coffee would still need to pass sensory evaluation.

The roasted coffee assessment was interesting as it displayed the limitations of visual assessment when determining roast degree along with the need to taste. The Agtron scale was one of the assessment tools available to the students, we had the SCAA colour tiles as a reference. The more expensive and accurate instrument for this task is the M-basic scale, it uses a colour analyser and assesses how much light bounces back from something and then correlates this to a number. For a coffee to be within the colour range that the Q defines as an acceptable colour within which to judge and grade a coffee is 58 for whole bean and 63 for ground coffee, or 55-60 for the colour tiles. However, the colour scale is not a complete assessment of a roasted coffees state. During the test, one coffee was darkly roasted and fell below the specified colour spectrum, another was quick and light and sat above the accepted Agtron number. Two of the sample however displayed a similar Agtron colour but were roasted in very different ways, One was a baked coffee, roasted slowly over a longer period of time and displayed its baked, yeasty, smooth but flat flavour profile once cupped. Roasters will of course be familiar with how varied the flavour results can be even with a familiar roasted appearance. All the same, the practical exam is a nice exploration of this premise, and an indicator of how an Agtron meter accompanied with other measurements can be useful.

Much like the cup of excellence protocol, the cupping scores that each student provides during the Q are processed in order to see wether the student is marking too safe(basically marking everything down the middle) whilst also not being all over the place and out of calibration. Each student was aware as we moved through the week, wether or not we had passed or failed a section. The cupping scores require a longer input process, meaning that it takes a couple of weeks post course to determine wether or not you may have passed.

Popping back to my blog, when is speciality coffee not speciality coffee, this course, by its nature is focused on looking at this question. From the Qs point of view, the line for speciality is located at a score of 80, with those falling under slipping to commercial grade. Tracy is all too aware of the issues with classification, and that a speciality coffee can very easily through various hands fail to be representative of when it was originally graded. The Q program works with many coffee organisations and they are currently looking to pass a packaging regulation. One that would mean for a coffee to be labelled as speciality it would have to display its authenticated grading score as endorsed by the Q program. In fact as a qualified Q grader you are eligible to act as an expert witness in court cases that focus on mis labelling etc. You would be sent an unmarked sample and be asked to grade the coffee under Q regulations – quite a responsibility.

They are very much aware that this is one step in a classification process, with the intent to look at roast and crop freshness to also be a part of a classification system for speciality coffees’ on sale to the public.

The Q is also something that is always being developed and updated, with this being Version four of the program. The emphasis is evidently on providing a valuable learning experience for the students whom take part, whilst keeping the qualification itself as valuable as possible to the industry. The tutors are also constantly undergoing rigorous testing and training, with there currently being only four qualified instructors worldwide.

Overall, what makes the Q (in my opinion) even more valuable and useful is the way in which it is taught, and the ethos behind it. There was always a readiness to emphasise when a topic was not simple or black and white. With the emphasis being on valuable learning and processes that stem from considered teaching rather than a simple paint by numbers learning.

Comments Off

Filed under Uncategorized