In The Peculiar Fate of Holly Banks, Book 2 in the Village of Primm collection, Holly’s husband Jack’s interest in coffee roasting is revealed to readers. While writing this novel, I found myself nerding-out and going deep into coffee roasting research for home enthusiasts. What’s possible, what isn’t. A lot of what I wrote was cut from the final novel. Both Holly and Jack are coffee lovers, a challenge for me to write sometimes because I’m a tea drinker. But I’m also a wine lover, and have, for years, studied viticulture and enology, so I’m fascinated by the art and science of drink-making.
I have a Coffee Roasting board on Pinterest. Take a peek.
Welcome to my Incomplete Guide to Roasting Coffee Beans at Home
Beginning with . . .
THE COFFEE BEAN
A coffee bean is the seed of a small, fleshy fruit. Often yellow or red when ripe, it’s commonly referred to as a coffee cherry, taking this name because of its visual similarity to a cherry. (To me, I think they look more like cranberries.) High in antioxidants, it’s the coffee cherry that contains the caffeine. Once that seed (the green coffee bean) is processed, a procedure that involves removing the outer skin, pulp, and inner parchment skin, the bean is then dried and roasted. Without roasting, the swill in your cup would taste acidic and bitter and not quite what you’d want first thing in the morning. The beautiful flavors and aromas you enjoy are brought about through the roasting process.
Stripping a fascinating process to its bare essentials, coffee roasting involves taking the moisture out of a green coffee bean, causing it to dry and expand. As you roast, some of the natural sugars contained in the bean convert into CO2 gas. Other sugars caramelize, creating flavors coffee lovers crave. Eventually, that green bean will become brown, and become about 18% lighter in weight, and about fifty to 100% larger in size. Within days, some of the gases that built up during the roasting process will release. Escaping gases create a challenge for the coffee roaster because those gases become small bubbles of air pockets if the coffee is brewed too soon because it alters the contact between the coffee grounds and the water which can lead to an uneven flavor extraction and compromise the aroma compounds. In short, don’t rush to brew. On the other hand, degas too much and your flavors will be muted. No spoilers here, but I imagine this is just the sort of error Jack would be making as he’s learning to roast at home.
COFFEE ROASTING IN 10 (SIMPLIFIED) STEPS
Roastycoffee.com, one of my favorite resources when researching, explains the following ten steps in greater detail in their post on coffee roasting. Below is my simplified version, borrowed heavily from the post I just linked to. NOTE: There’s more nuance to roasting than these ten steps, but this is essentially the gist of it. Also, different people, companies, and organizations, like the National Coffee Association, issue steps ranging from seed to cup (or similar), so what follows is certainly not a comprehensive list. For one, it doesn’t address the planting, harvesting, drying, milling, etc.
Okay, enough about all that.
- Green – beans in their original green state
- Yellow – beans start to yellow and smell grassy
- Steam – as moisture from the bean starts to evaporate, steam rises
- First Crack (cinnamon roast) – sounds of crackling (like popcorn popping) begin as sugars start to carmelize
- City Roast – the minimum level of roast
- City Plus Roast – popular and common level of roast which happens as more sugars caramelize and oils begin to migrate
- Full City Roast – beans appear even darker, but not quite at the point of the second crack
- Second Crack (Full City Plus Roast) – second, more violent crack – flavors intensify and become layered
- Dark Roast (French Roast) – smoke becomes pungent and you’ll ruin the flavor if you continue to burn the sugars; the overall structure of the beans break down
- Burn – reach this point and the pungent smell will move to unpleasant – you’ve just burned the beans (toss ’em out or serve them to your wife as Jack does in the novel)
I have more I want to say about Holly and Jack’s love of coffee, but I think I’ll save that for another post. In the meantime, what are your thoughts about roasting coffee at home? Are you thinking about roasting your own coffee?