‘CM Selections’: a new future for coffee processing

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In early March, the Project Origin team launched a project we have been working on for several years: a new selection of green coffee, ‘CM Selections’.
Since launching, we have been asked a few questions about the Selections and what it means – so, we thought we’d answer a few of your questions!


What exactly does ‘CM Selections’ mean?

CM’ stands for Carbonic Maceration. It is a process that is generally used in winemaking, in which whole grapes are fermented in a carbon dioxide-rich environment prior to being crushed for their juice. We have adopted a method which also utilises carbon dioxide in order to push boundaries of fermentation and development in coffee. So, the CM Selections is our selection of coffees that have been processed using this method.

How is this processing different from normal coffee processing? 

The terms that we are accustomed to in the coffee world include natural, washed, honey, semi-washed and so on. These processing techniques use a variety of methods to extract the green beans/seeds from the coffee cherries.

The CM process does not replace these methods; rather, it adds another step in processing. For example, the CM Selections coffees are still identified as being natural, washed, etc but as they also do through this maceration process, we need to include that information too. So instead of being just washed, we say that a CM Selections coffee is carbonic macerated (washed). 

Coffee cherries are picked perfectly ripe, hand sorted and floated to remove unripe and over-ripe cherries. The washed CM Selection coffees are then pulped, before being placed in temperature and humidity controlled tanks flushed with carbon dioxide (CO2) to remove oxygen from the tank. Natural CM Selections coffees are placed in the tanks and after fermentation, the coffee is dried on African beds for 12-18 days before being stored to rest before dry milling.

What does the carbonic maceration method do to the coffee? 

The result of a carbonic maceration process is increased development of flavour profiles. By using a controlled, carbon dioxide-rich environment to ferment the coffees, we can control which yeasts and bacterias are active during fermentation and for how long, and this are able to intensify and further  develop the flavours of the coffee without risk of over-oxidization or alcoholic fermentation, which will ruin the profile of the coffee.

Who came up with the idea? 

The carbonic maceration method is often attributed to winemakers in Beaujolais, France. In the coffee world, it was first publicly introduced by Project Origin founder, Saša Šestić. In the entry for Carbonic Maceration in his book The Coffee Dictionary, Maxwell Colonna-Dashwood says the following:

“It was in 2015 at the World Barista Championship that the coffee community was introduced to the idea [of carbonic maceration] when the Serbian-born Australian Saša Šestić won the competition with a coffee that made use of the method … Šestić, together with his collaborator, the Colombian farmer Camilo Merizalde, experimented with this technique to produce a coffee that had more aromatic complexity but a lower concentration of sharp-tasting acetic acid.”

So does carbonic macerated coffee taste better than other coffee?

Taste is of course a subjective experience, and what tastes ‘good’ and ‘bad’ depends on what different people like. The CM Selections coffees aren’t ‘better’ than any other coffee; they offer an experience that pushes the boundaries of development, so that the consumer can experience intensity in flavour and aroma.

Are carbonic macerated coffees all high-scoring?

In the coffee world, we of course use different scoring techniques and systems to determine how we categorise coffees. These are used in everything from cupping, sorting and buying through to global competitions.

We categorise all of our coffees according to a three-tier grading system: Black Label (83-85), Green Label (86-89) and Gold Label (90+). However, with the CM Selections coffees we have decided to opt for a new system of categorisation.

How are the CM Selections coffees categorised? 

When we first began developing CM coffees, we greatly enjoyed them for their incredible flavour expression, aromatic intensity and quality of acidity. However, it was hard to judge these coffees using normal scoring standards – so, we began to categorise the coffees according to their flavour profiles and came up with four different names to identify these profiles:

The Indigo range of CM Selections includes coffees that have a profile of intense flavour, powerful fruit qualities and unique elements. This includes coffees that have undergone extensive and experimental fermentation, creating bold and strong flavour profiles.

The Jasper category of CM Selections includes those coffees which have a flavour profile reminiscent of red, orange and yellow fruits. These coffees have undergone a range of carbonic maceration processes, in order to provide maximum flavour and clarity with medium level intensity.

The Amber range of the CM Selections includes coffees that have a delicate flavour profile and sweetness, with a flavour profile of orange and yellow fruits. The CM techniques used to process these coffees look to maximise delicacy and transparency of flavour, rather than intensity.

The Diamond category of the CM Selections is the most elegant and delicate of the four. The coffees in this range are floral and clean, with a refined and gentle flavour profile.

When will these coffees be available? 

We are in the process of finalising shipping and distribution of the first of our CM Selections coffees from Ethiopia, and are awaiting samples of further experiments from El Salvador and Honduras. We expect to have many of these coffees available within two months.

Can I request samples of the CM Selections coffees?

We will be offering samples of several of the CM Selections coffees in the coming weeks – if you are keen to sample some of these coffees, feel free to get in touch!

For further information, contact:

[email protected] or [email protected]






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