Coffee Day 1: The Best I Can Hope To Be Is a Buffoon With a Certificate

Boot Coffee Campus, in San Rafael. It looks unassuming from the outside, but inside is like heaven for coffee nerds.

As we stood around the white granite counter at Boot Coffee Campus waiting for class to start for the day, we started talking about why we were here and what we hoped to get out of the course. Three folks are just here for one day: today's course is the SCA (Specialty Coffee Association) Introduction to Coffee, an intensive overview of each step in the process of producing coffee from seed to cup. Two more are here for the week: from Tuesday to Friday, we're going through the SCA Sensory Foundations and Intermediate courses, which cover coffee tasting. Then there's just one person (me) who's here for two weeks, to take the Q Grader course and exam.

Valerian, our instructor, says "Q Graders must stay calibrated by cupping regularly with others. A Q Grader who doesn't is just a buffoon with a certificate."

As class starts, we take turns introducing ourselves. One of my classmates is a coffee roaster specializing in extremely highly rated green coffees. One runs a coffee farm that recently placed in the Cup of Excellence. One is starting a coffee roasting business and cafe. I feel like I'm in over my head taking two weeks of intensive coffee classes as a post-layoff crisis move. Like I'm an imposter among these people who have been living in the coffee world and have a clear reason to take this training.

When it's my turn to share, I tell the class that by the end of next week, we'll find out if I'm a buffoon with a certificate, or a buffoon without one.

It's Monday, and the course is Introduction to Coffee.

I'm taking two weeks of classes at Boot Coffee Campus in San Rafael to prepare for and take the Q Grader exam. Boot is one of the most serious coffee centers in the Bay Area. It's both a coffee lab and a teaching campus that trains people to work professionally with coffee from roasting to brewing to business.

The two weeks of classes I've signed up for are actually four separate classes, three that follow the Specialty Coffee Association (SCA) curriculum and one (the Q course) from the Coffee Quality Institute (CQI). They are as follows:

Monday, June 12: SCA Introduction to Coffee
Tuesday, June 13: SCA Sensory Foundations
Wednesday, June 14 - Friday, June 16: SCA Sensory Intermediate
Sunday, June 18 - Friday, June 23: CQI Q Grader Course and Exam

Those last two classes are going to be intense (as you can see, there's only one day of rest between them), but today was relaxed and fun. We went through coffee's journey from coffee cherry to brewed beverage and got little peeks at each step of the way: growing, harvesting, processing, roasting, and finally brewing. Because this class is part of the SCA curriculum, there's a short test at the end that you have to pass to get credit. The majority of this post was the result of me organizing and reviewing my notes to prepare for the test, along with a few small anecdotes from the day.

Before we dive into it, I just wanted to say that the whole day was a blast. In most of my social circles, I'm the weird coffee person, but being in class with a bunch of fellow coffee nerds and our incredibly knowledgable instructor, Valerian, was great. I got to talk about coffee all day with people who cared about it as much as I do (and often had far more experience than me). Being in a coffee lab with an instructor is a very different experience than learning on my own online: it was great to be able to pester Valerian with coffee questions and get accurate answers in real time instead of picking up knowledge piecemeal from coffee YouTube, and he had a whole slew of different coffees, equipment, and books to illustrate what we were talking about so we could taste and experience things instead of just hearing about them.

I had gone back and forth on whether to add this course to my curriculum because (like all courses at Boot) it was a professional-sized investment. Reflecting on the day, I'm confident it was worth it. I can't think of a better way to kickstart a serious learning journey into the details of how coffee happens for someone who wants to go beyond brewing (which is where I started).

If you're interested, you can see upcoming courses on their website here:

https://bootcoffee.com/calendar/

General Facts About Coffee

Coffee grows between the Tropic of Cancer and the Tropic of Capricorn.
It's a low yielding crop because we only use the seeds. This exacerbates the economic problems of coffee growing. Not a lot of people want to work on growing coffee when the yields are low, the processing is risky, and the price of commodity coffee hasn't kept up with inflation for decades (ignoring large swings in price).
The top coffee drinking countries per capita are in Scandinavia: Finland tops the chart at 12 kg of coffee per year per capita, followed by Norway (9.9 kg), and Iceland (9 kg). Anecdotally, the cold, dark days lead to lots of coffee drinking. (In my notes I just wrote "Sad = Coffee".)
80% of coffee is grown by small land owners (<12 acres of land) vs 20% from large farms (e.g. more common in Brazil). Over 10 million families worldwide get income from coffee growing.
Farmers may multi-crop coffee to buffer their income, for example, growing veggies between coffee trees or planting crop-bearing shade trees like bananas.

Species and Varieties of Coffee

There are several species in the genus "coffea" which are all different types of coffee. The most common are Arabica (coffea arabica, 60-75% of global production), Robusta (coffea canephora, <40% of global production), and Liberica (coffea liberica, <1.5% of global production, but makes up the majority of coffee produced in some countries, such as the Philippines).
Fussier coffees tend to taste better but are harder to grow.
Coffee plants need cold nights to slow the production of cherries. This usually happens at higher elevations, but the elevation (usually expressed as "meters above sea level", or MASL) only matters in context of the geography. A farm at 2000 MASL in one country might be high in the mountains, experiencing cool nights, while 2000 MASL in another country might be covered in snow (where you can't grow coffee). Elevation is a proxy for growing conditions, and a higher elevation may indicate that a coffee is experiencing cooler nights that will likely yield sweeter cherries, but it's really the environment that makes the difference, not the elevation, and elevation is only meaningful in context of where the origin is (e.g. which country the coffee is from).
Most varieties of arabica are hard to tell apart from each other because they diverged from the typica (?) variety relatively recently. The ones that taste the most different include Gesha, varieties from Yemen that have been developing for a long time alongside typica, and varieties from Ethiopia where coffee trees grow wild in the forest and yield new, unique flavors.

Arabica (coffea arabica)

Makes up 60-75% of global production.
Usually oval shaped beans.
Likes an average temperature of 66-72 F (19-22 C).
Native to Ethiopia and Southern Sudan.
Named after Yemen (which is on the southern edge of the Arabian peninsula), where it was historically cultivated.
The Dutch stole it from Yemen for cultivation in their colonies (e.g. Indonesia – Java). Eventually gave some seeds to the French, who introduced it to their colonies (e.g. in the Carribean).
Was a hybrid between coffea canephora and coffea eugeniodes. Has a bunch of varieties and cultivars, including ones that are crossed again with canephora.
Top producers: Brazil, Columbia, Ethiopia, Indonesia
Pros: Self-pollinating, potential for more sweetness and fruit/floral notes
Cons: Lower yield and more susceptible to disease (requiring colder growing environments) than robusta. Fruit doesn't ripen all at the same time, requiring 3-6 picking passes to get the fruit at peak ripeness (very labor intensive).
In the Cup: Can have complex and layered fruit flavors, up to 2x the perceived sweetness as robusta, less bitter, less body, more acidity.

Robusta (coffea canephora)

<40% of global production
Usually round shaped beans.
Likes an average temperature of 74-86 F (23-30 C).
Native to Western & Central Africa (though these origins are less well known, perhaps b/c the specialty world doesn't put as much emphasis on robusta compared to arabica).
Top producers: Vietnam, Brazil, Indonesia
Pros: More resistant to disease, grows in warmer areas. Fruit ripens at the same time, making it easier to pick ripe cherries (e.g. can strip pick or use automated pickers).
Cons: Needs cross-pollination, less sweetness and fruity/floral notes.
In the Cup: Usually has a low quality flavor, lacks sweetness, more bitter, more body, more chlorogenic acids (antioxidants that are often lost in roasting, but they don't taste good), less acidity.

If you wanna see more about coffee species and varieties, Cafe Imports has an awesome infographic on their website. I've also linked to a couple videos about other varieties and species at the bottom of this post.

Senses Involved In Experiencing Coffee

Smell ("Olfaction"): Happens in your nose, in the olfactory bulb. Smell is a huge aspect of "flavor".
Taste ("Gustation"): Happens on your tongue. The basic tastes are salty, sour, sweet, bitter, and umami. (Though this model may be oversimplified and some cultures claim that there are additional basic taste modalities. e.g. Kokumi) Since smell is such a big part of flavor, it's not quite accurate to say that something "tastes like strawberry" since the fragrance of strawberry is not something you taste, but a combination of smell and taste.
Touch ("Taction" or "mouth-feel"): Happens on your tongue as well.

Sweetness in Coffee

Sweetness in coffee often refers to the perception of sweetness vs the actual amount of sugar that is physically present in the drink.

Two Types of Bitterness

There are two sensations that we commonly refer to as "bitterness" that we can distinguish in coffee:

"Drying": The "bitter" taste of unripe fruits like permissions or astringency like in a wine.
"Bitter": The "bitter" taste of a beer.

TBQH I don't entirely understand this distinction right now, but I'm sure it'll come up again later in the course.

According to the SCA, the dominant tastes in coffee are "sour" and "bitter". Arguably, sweetness is another critical aspect (especially of specialty coffee), but that's the official line.
The bitterness in coffee is mostly caused by caffeine (and to a lesser degree by chlorogenic acids and burnt sugars). Caffeine is a natural pesticide and a stimulant to humans. Some bugs like caffeine though. One is a pest, called "broca" or coffee borer. The other one is pollinating bees. The coffee flowers contain a slight amount of caffeine, which gets bees buzzed 🥁🫰.

Growing Quality Coffee

Factors of Quality Coffee (according to the SCA?)

Climate
Altitude
Soil Type
Microbiome (in the soil, and on the plants)
Green bean size, quality, and age

Coffee likes shade. Even though full sun increases yields, this comes at the cost of flavor quality.
Coffee trees grow up to 20 ft tall in the wild, but are usually pruned to 8 ft or less when cultivated to make it easier to harvest.

Anatomy of a Coffee Cherry

There are a bunch of illustrations of this online that are readily available, so these are just notes from playing with some at different stages of processing.

There's a coffee tree inside the training center that has ripe fruits and some drying flowers on it still. The flowers smell like jasmine when fresh, but have a slightly mustier scent now that they're dried.
I picked a cherry off the tree and ate it. It was sweet and much more berry-like than cascara (the dried coffee pulp) which has a more sour, hibiscus-like flavor.
From outside to inside: Outer skin (comparable to the skin on a date), pulp (this gets turned into cascara in some cases), mucilage (the slimy layer surrounding the seed, similar to when you eat a stonefruit and there's a layer around the pit), parchment, silverskin, endosperm (the bean itself).
The parchment and the silverskin are not the same thing even though they're adjacent layers. The parchment is thicker and is removed before the green coffee is shipped. The silverskin is lighter and thinner and wraps from inside the crease around the entire bean.
Seeds that are meant to be planted (instead of roasted) should stay in the parchment.
You can emulate the honey process by eating a coffee cherry and spitting out the seeds.

Processing Coffee

Green coffee beans that are over a year old are called "past crop", though green beans can be kept fresh longer by keeping them in plastic-lined bags (e.g. GrainPro) or vacuum sealed. Green coffee ages by losing moisture.

In addition to my notes from the class, I've linked some videos from Cafe Imports that show some of these processes in action in real farms. You can find the whole playlist here.

Harvesting Coffee

Can be done either manually or by machine.

Manual Methods

Selective picking: Hand pick individual ripe cherries. Best quality, most labor intensive.
Strip picking: Picking all the berries off a branch at once. May get some unripe berries.

Machine Harvesting

Usually shakes berries off the tree and picks them up. This requires picking up some berries that fall to the ground.
If some berries fall to the ground and start to dry and then are subsequently picked up by the machine (say, in the next harvest), this can introduce bad cherries to the lot, which results in some classes of defective green beans.

Washed Process

Step 1: Sorting

Two options for doing this:

Hand Sorting: Separate ripe cherries from defective ones by hand. Slow and very labor intensive.
Floatation: Put the cherries in water. Defective or unripe cherries float to the top and can be removed. Takes lots of water to do, so it's not viable in all producing countries.

Step 2: Depulping

Three ways to do this:

Mechanical Pulping Machine
Hand Pulping Machine (used in smaller operations)
"Eco Mills", which allow you to adjust how much mucilage to remove.

Step 3: Fermentation and Washing

Fermentation allows micro-organisms to digest part of the mucilage (pectin) that coats the parchment layer of the seeds, making it easier to remove by washing.

A wet fermentation can take anywhere from 12 hours to 3 days (e.g. in the Kenyan process).

After the fermentation is complete, the mucilage can be removed by agitating the seeds in water. In the Kenyan process, there's additional soaking, which allows certain characteristic flavors to develop.

If you screw with this fermentation, you can get crazy flavors, but doing so trades off against expressing the terroir.

Step 4: Drying

The green coffee needs to dry to 10-12%. This process takes around 3 days to a week.

There are 3 common ways to do this:

Machines: Drying machines can be fast, but quick drying doens't always lead to the best flavors.
Patios: Beans are left outside on a patio made of concrete, tile, or even soil and turned periodically to let them dry uniformly (e.g. with a rake). This is a very traditional and accessible way to dry coffee and is used in many growing regions.
Raised Beds: This is classically used in Ethiopia, though some other origins are adopting it as a modernization method. Drying on raised beds can allow more airflow, and the slow drying (vs a machine) can improve quality. However, this requires more space than the other methods.

Step 5: Storage/Resting ("Reposo")

The dried coffees must be left to rest with their parchment layer still on. This stabilizes the humidity in the beans after the drastic changes they undergo in fermentation and drying. This can take a month, up to 3 months or until the beans are ready to be exported. Failing to rest the beans may lead to astringency in the cup.

Step 6: Hulling

The green beans are hulled to remove them from the parchment layer (leaving just the silverskin and the endosperm) prior to exporting.

Natural Process

"Dry processed" or "natural" coffees are dried in the cherry instead of being pulped, fermented, and washed. This is the most traditional way of processing coffee and is still used for flavor reasons or in places that don't have enough water to use the washed process.

Step 1: Sorting

(Same as washed)

Step 2: Drying

This is done in the cherry, without pulping. The dried fruits look like dates or raisins. Some amount of fermentation occurs naturally, but not a ton as it slows down as the coffee cherry dries out. This process can take 3-6 weeks.

There is a lot of risk for farmers in natural processing since mold and other issues can develop while the coffee dries. This process takes about a month, vs around a week for the washed process. Many farmers don't get to drink their own coffees and aren't making production decisions explicitly for quality, so it's likely that many farmers choose the washed process over natural because of the risk to their business vs an aesthetic decision about what kind of flavors they want to come out in the cup.

Step 3: Storage/Resting ("Reposo")

Similar to the washed process, but the coffee is stored in the cherry.

Step 4: Hulling/Milling

The outer layers of the cherry including the pulp, mucilage, and parchment are removed before export.

What Makes a Coffee "Specialty"

Five factors:

Green coffee is free of defects.
Has a score of 80 points or above as determined by qualified Q graders.
Traceability: Has a story.
Of a Place: Terroir
Has unique aroma & flavor profiles

The first two qualifiers are called the technical requirements.

💬

"Starbucks and Folgers sell coffee, we sell stories." – Valerian

Roasting and Brewing

There were a lot of small sections here, so these are just a few key notes.

Roasters can be powered by gas or electricity. Gas roasters are more reactive since electric heating elements take time to heat up (vs. gas which can increase its heat quickly).
An affordable sample roaster is the Huky 500, from Taiwan. You can get a good price if you buy it direct.
Coffee loses 12-20% by weight when roasted. Most of the lost mass comes from water and carbon dioxide. The volume of the beans can double, depending on the roast level. Dark roasts are less dense and take up more space (plan for bigger bags than for the same weight of a light roast, or don't be surprised when it doesn't fit).
Caramelization reduces sugars to create caramel compounds. Even though we perceive caramel as sweet based on our associations, this process actually reduces sugars.
SCA recommends a brew ratio of 50-60g of dry coffee per liter of water. Target 1.15-1.45% strength (proportion of the final drink that is comprised of extracted coffee material) and 18-23% extraction (proportion of coffee solids that were moved into the cup).

A Simple, Competition-Winning Aeropress Recipe

This recipe was meant to be easy for customers to remember and was developed by Valerian's cafe/roasting company Green Plantation.

A version of this recipe won the World Aeropress Championship in 2015.

Start with the Aeropress in the inverted position.

Bloom for 30 seconds.
Add remaining water and give the ground a stir.
Let stand for 30 seconds (inverted).
Flip and press for 30 seconds.

Brewing water for coffee must be odor free. The most common contaminant is chlorine. 195-205 F (SCA recs).
Cleaning: Yes. Cafiza.

Highlights

I ate a coffee cherry fresh from the tree. It's sweet and berry-like. The part I spat out, the two seeds at the core, are unprocessed green coffee "beans".
I tried a lot of excellent coffees. A coffee from La Mula that tasted more bright and fruity than a Starburst. A coffee from El Salvador that won 4th place in CoE (peaches and tea, roasted almonds, honey).
I tried a coffee that was processed two ways: as a washed and as a natural. The natural was sweet and syrupy with a tropical fruit flavor. The washed was citrusy, balanced, and pleasant. Valerian said that you can get one coffee processed multiple ways more often now as producers expand their catalog of coffee types by exploring different processing methods.
I tried a robusta coffee that I actually enjoyed. One of my classmates said it tasted like black sesame, and it was like a light switch flipped in my head. This was a high grade robusta, so it didn't have as much of the rubber / ash / asphalt taste to me as others that I've tried, and the thick, oily taste was pleasant once I thought of it as sesame.
Valerian shared an observation that of the many students he's met, he felt that the ones who paid attention to the business side of the roasting class were more likely to succeed in their ventures than those who only wanted to focus on roasting good coffee and nodded off in the business side. To paraphrase, "In the coffee business, the coffee is just one part of the equation. The business is the majority of it."
Valerian has a podcast. I haven't listened to it yet, but I plan to.

On Taking The Q

One of my classmates who took the Q here in the past, and had been in the Coast Guard, a cook, and a triathlete said, "You'll be ok, and whether you pass or fail you have to go into this with the attitude that you're here to learn. It was tough and intense, and at times I felt like I was going to cry, but eventually I got it."
Valerian said (and I'm paraphrasing heavily), "Don't worry. You have a long couple weeks ahead of you, but you'll be ok. The class is like magic. You don't think you can learn that fast, but it works."
Also Valerian: Confidence is an important attribute for cuppers. I've coached people who had excellent cupping skills, but lacked confidence.