August 05, 2015


WHAT MAKES A GOOD COFFEE GREAT?

The Making of a Brazilian Coffee

I have been mulling over this question for a while; what really makes a cup of coffee

stand out from the rest? How do you determine its defining factor of quality? There

are so many things at play in what we have come to understand as quality, but I

really think we are still somewhat unsure of what it actually is. At many points in a

coffee cherry’s life, events occur that can produce (or take away from) quality. The

actual processing of the coffee is one of these defining moments. It is a fantastic

manipulator of flavour, and can be used to craft nuances that can only be unlocked

by skilled workers. I find the idea of changing flavour by tweaking the processing

absolutely fascinating! I want to take some time to dig a bit deeper into processing

methods around the globe. Each method is unique, developed for their particular

environment and each have a huge impact in the cup. It is kind of like a craft brewer

manipulating fermentation to produce different results.

Most of us are aware of the different methods of processing coffee, at least as far as

understanding natural, honey and washed process. If you need to brush up a little,

make sure you have a look here before reading further.

http://bit.ly/1IIU69f

I intend to go a bit deeper than the cursory understanding and

look at the specifics for each country, the terminology and slight differences.

Brazil is one of my favorite origins, so it makes sense for me to start here; they have

such interesting and advanced techniques for harvesting and processing. The cutting

edge technology used on these farms is incomparable anywhere in the world.

A large part of what is done at farm level in Brazil is mechanised. Labour costs are

high and so much of this has developed out of necessity. Most of the harvest is

picked mechanically, or through using a method called strip picking, where the

branches are literally stripped of all their fruit. For someone who has only seen

selective picking, it can be quite jolting to see this treatment of the trees. You might

even argue that it is a shift away from specialty coffee, but at the end of the day, cup

quality does not lie.

The mindset in Brazil is to pick it all and sort it out later. Whereas the mindset of

specialty producers in Latin America (for example) is to only pick the ripe coffee, only

when it is at a perfect level of ripeness. It all makes sense when you start to dig

deeper into how they process their coffee. In small specialty producers outside of

Brazil, the technology to perfectly sort the cherries just does not exist.

Rather than pick perfectly ripe cherries between 19 and 23 brix (the amount of sugar

in the fruit) by hand, the Brazilians leave the fruit on the tree until it is closer to 23 all

the way to 30 brix, super sweet. So already we have the influence of a much riper

fruit. Typically the farm will time the harvesting to the day when each branch has

the least green fruit, and the dried pod cherries are not so aged they are

dropping to the ground, or moulding on the tree. This takes a pretty experienced

eye to work out; however, careful monitoring and years of practice have

perfected the technique.

 

In Brazil they have four types of processing: Natural (dry), pulped natural, semi-

washed, and washed. The majority of coffee is dry processed (or natural

processed); this is the traditional method that is still widely embraced in the

regions of Cerrado Mineiro and Mogiana Paulista, where harvest coincides with the

dry season.

 

The term “Natural” came about as a way to differentiate the process from the

“Washed Milds” of Central America and Colombia. They wanted to have their own

term to use for marketing, and “unwashed” just didn’t fit well for them

(understandably). Ethiopia quickly took up the baton as well, but what we understand

as “Natural” in Brazil is not exactly the same as what we understand as “Natural” in

Ethiopia. In Brazil Natural refers to a harvesting style rather than a processing

method. There are a heap of factors that are different between Ethiopian Natural

and Brazil Natural. Most notably is the way it is picked, where coffee is allowed

to dry on the branch and fruit at all stage of ripeness are picked.

In Brazil, typically the coffee is laid out onto patios to dry, direct from the trees.

These cherry pods that are laid out to dry are called boia (ball) in Portuguese.

As I mentioned a bit earlier, all the coffee is picked no matter the level of

ripeness, so there is a high percentage of coffee on the patio that is over-ripe

and/or raisin like. Some of the more modern Brazilian farms force-separate the

coffee before it gets to the patio, reducing under-ripe cherries, which is of

course preferred from a quality standpoint. This force-separation is typically

done with a siphon system where the under-ripe cherries are floated off the

surface of a water tank. Other, less advanced farms, or ones with access to less

water just combine the lot, which is why you get so many quakers (under-ripes)

in Brazil natural process coffee.

 

Traditionally, dry processing is what produces the leather, tobacco, woody notes

we are likely familiar with in Brazilian coffee, rather than sweet, balanced fruit-

driven flavours of many modern Brazil Naturals. Dr Flavio Borem of Universidade

Federal de Lavras (UFLA) has done a lot of study into processing methods and

particularly natural processing methods. His theory on producing cup quality in

natural process coffee (typically understood as having poor cup quality) delves into

controlling metabolic changes in the drying process to preserve sweetness,

complexity and body. Controlling drying temperatures and drying rate maintains cell

structure integrity. Cell membranes are susceptible to damage in natural process

coffee and this damage can result in foul tastes in the cup. This stuff all gets a little

deep so if you want to educate yourself some more I suggest you head here 

to: https://vimeo.com/52427194

 

About 25 years ago the pulp natural process was introduced to Brazil by

Pinhalense, a well respected machinery manufacturer. Pulp Natural is probably the

second most popular processing method in Brazil. It is known as Cereja Descascado

in Brazil, 'Descascado' means 'removing the fruit skin' and Cereja means 'cherry’. In

Central America it is also known as ‘Honey Process’ or ‘Miel’. Pulp Natural is of

course made possible by some great equipment (championed by Pinhalense) called

demucilagers, which in essence promote a unique sweetness in the cup. Typically

the coffee is stripped of its skin in a pulping machine. Afterwards, the mucilage is

washed off to the desired level before being dried, completely skipping the

fermentation process that is used in other processing methods. Since a fair bit of

mucilage can still remain on the beans when they hit the drying process, Pulp

Naturals can only really be executed well in places with low humidity so they can dry

quickly, reducing the risk of moulding. Once dry the Pulp Natural coffee is placed in a

wooden box called Tulhas to rest and gain a more ‘settled’ taste.

Semi Washed (desmucilado or without mucilage) is a bit of a hybrid process that has

gone out of fashion because of an adverse association with Sumatran coffee (Giling

Basah). It is often confused as being one and the same as Pulp Natural processing

but I have come to understand it as being just a little different. It gives coffee a big

body and is generally quite sweet. It is a process that can go very wrong easily but

conversely can provide a lot of variation if executed correctly. This is where it all gets

a little confusing. The coffee is passed through a demucilager, which is set to take off

as much of the fruit as possible. In Central America, demucilagers used in this way

mechanically wash the coffee; hence you hear the term Mechanically Washed.

Since you can set these machines to remove pretty much all the fruit, you can end up

with some super clean coffee. Once again the fermentation step is skipped and the

coffee is sent straight to the patios to dry. Semi washed coffees that are dried quickly

under constant conditions for the most part taste cleaner and less muddled than

coffees that are dried slower, these can have more fruit in the cup and a more

muddled or hazy flavour. This goes back somewhat to the learning from Dr Flavio

Borem.

The final processing method I must discuss here is of course washed process.

Recently, coffee producers have been showing an interest in producing washed

coffee, but demand is still lacking in national and international markets. This is likely

in part because of the poor reputation for quality that Brazilian coffee has held for

such a long time, but also because of the lack of washed coffee in the first place in

Brazil. Washed coffee is pretty much the same as the semi-washed process except

this time the coffee is fermented to help remove the mucilage. Typically this process

cleans up the cup profile and brings out acidity.

 

So that is Brazilian coffee processing in a nutshell, sort of. Once the cherries are

reduced down to parchment coffee, more sorting has to happen to make sure the

final product is speciality quality. The parchment coffee is typically taken from the

farm to a dry mill, where the coffee is prepared for export. Once the coffee is

received it is run through density sorting, a large flat bed that, through vibration,

separates out coffee based on density. Density can be used as a great indication of

quality. It is then run through a cleaning process and is finally sent to the colour

sorter before export. The colour sorter is a machine with a tiny laser that inspects

each bean for blemishes. So as you can see, sorting is all mechanized in Brazil. Not

only does this present you with a much better cup quality (machines make less

mistakes than people), but it also alleviates the in-country problem of high wages.

 

— Lucy Ward