Topic: Defects in Green and Roasted Coffee Beans
Coffee Smarter Expert: Alden Hozouri, Crossings Coffee Roasters
Connect: www.crossings.coffee • @crossingscoffee
KEY TAKEAWAYS
Defects in both green and roasted coffees are often identified visually.
Scorching or a burnt mark on the bean occurs when a bean is pressed up against the wall of the roaster drum too long.
Tipping or big fissures on the top and bottom of the bean occurs when the bean was heated to 1st crack to quickly.
Baking occurs when a bean has been dried out during the roasting process. It is hard to see but easy to taste. The beans will tastes flat and cardboard-like.
Look at the beans! Is there a lot of color variation? It could be part of an unevenly roasted batch. Crack it open. Is the color even all the way through? In coffee, consistency makes for a balanced coffee.
Look for sorting issues when examining your green coffee beans. Drastically mixed sizes or color variations may indicate a poor sorting process and result in coffee the ultimately tastes muddled no matter how well it is roasted.
LISTEN!
Alden explains coffee defects in all forms to us. Transcript below.
Listen to this short clip, featuring Alden Hozouri.
INTERVIEW*
R!WC: Hey, Alden, welcome back to another Crossings Coffee Corner. I think the first one last month went really well. We kept it to our 10-minute time limit, which made me, as the person editing all this, very excited. So I'm gonna stop blathering on. What am I learning about coffee today?
Alden: We're going over coffee defects.
R!WC: When you say that, I assume you're talking about the coffee bean. Are we talking about green coffee beans like I'm an at-home roaster, or are we talking about already roasted beans I'm getting ready to brew?
Alden: I'm a little ambitious, so I kind of want to cover both, but for the bulk of our conversation, we'll be going over-roasted coffee.
R!WC: Okay, well, let's start there. How do I read one of these roasted coffee beans and figure out what's wrong with it or what's right?
Alden: Yeah, that's a terrific question. So, I'd say, for the most part, you're not going to know until you get the experience and have a wide range of different beans to look at, to kind-of compare and see what one has and the other one doesn't. But if you were to just take a single handful of beans and kind of just look at them right in your hand, there are a couple of things you can immediately look at and look out for to determine if that roaster or if that bean itself is right for you.
Objectively, there are a few things that roasters will consider after a bean or a batch has come out of the roaster. We're gonna be looking for things like scorching and tipping and baking and color distribution. And these are all words that might mean nothing to you. So I'm gonna break them down kind of one by one. When a bean enters a roaster, imagine a big drum that's rotating over a fire. This is how most roasters these days are built. The beans make contact with the side of the drum itself. And that's a good thing because there are two different ways that we roast beans or that beans are roasted convection and conductive heat, kind of like your oven, you've got convective and conductive modes, convection is going to be kind of the air around the bean.
So the ambient environment that is cooking kind of like an air fryer. Conductive is going to be contact-to-contact. So the being touching the side of the drum wall or touching another being transferred directly from that contact. These are the primary ways that we see beings eventually getting roasted to this final product. However, when you have conductive contact-to-contact heat transfer, sometimes beans can press up alongside the drum wall for too long. And kind of like when you throw a vegetable or a piece of meat on a hot skillet for too long, you get a birthmark, and we call that scorching. And that'll look kind of like a glazed or really dark spot on the bean, where they've been may have been pushed up against the wall.
On the other hand, you can get what we call baking. And this is visually pretty hard to see, if at all possible to see in the first place, but you'll taste it in the cup. And it's going to taste kind of cardboard and really flat, it's not going to have a lot of dynamicism in the cup itself or even in flavor is gonna taste really kind of bland. And that's a result of poor airflow and bad convective heating, where basically the beans dried out. And it's baked rather than being deliberately roasted to its completed state. Other things we can see are what we call tipping and what the skin looks like. If you look at the bean, on the top and bottom, you might see some cracks and these fissures. That happens during the roasting process at what is known as first crack. Whereas the bean is entering this phase, where moisture inside the beam is building up to a vapor, the bean actually pops in bursts open, kind of like popcorn. This is totally normal.
It's absolutely normal to see small little cracks and things like that. And so we restructure the bean itself. However, if you start seeing really big fissures at the top and bottom of the bean, that is an indicator that the bean entered first crack way, way, way too fast, where there's so much pressure built from all that thermal heat and theme being literally erupted. That can really disrupt a lot of the cellular integrity of that bean, which usually means that there was a lot of rapid transition transitory phases as the being went from, you know, a yellowing to a golden color to, you know, the phases in how the bean has been caramelized. When you don't let the bean transition through the stages more smoothly, in a more controlled manner, you can get a lot of inconsistent flavors in your cup, as well.
R!WC: I'd like to point out that all of this sounds like roasting coffee is much harder than throwing it in the oven and walking away, which is what I do most of the time. Anyway, continue.
Alden: Yeah, so these are the two things I would say you want to look out for as well. Also, on a wider scale, if you take a handful of beans and you're looking at them, and you know that this is a like a single origin, or at least like a regional select where it's not like a blended bag of coffee, and you're seeing a lot of color variation, like some are really dark, some are a lot lighter, and it's very inconsistent. That's an indicator of usually poor airflow in the roaster itself. Maybe the roaster had filled the drum with too much coffee, so there wasn't enough room for error to pass through. You know any number of things, but if you're seeing a wide range of colors, and when that could be an indicator that not each band was roasted evenly. And you might see that in your cup.
The final thing I would say to look out for is if you get a bean and you crack it open with your fingers, like smash it on the countertop and take a look at the pieces. What we want to see is an even color all the way through. But if you're noticing, it's darker on the outside and lighter on the inside, which usually means that the bean was not evenly cooked. Maybe the bean was thrown into a drum, and it was too hot, so the outside cooked before the inside could cook evenly. Kind of like when you cook a steak. We all want to see across, and maybe some of us like our steaks more rare than others, but with coffee, we want to see even color all the way through.
What does that kind of look like in your cup? You're gonna get a cup that tastes really over-extracted and also under-extracted because you've got over-extracted and an over-cooked part of the bean on the outside. And then the underdeveloped part of the brain on the inside.
R!WC: You said something at the beginning of this chat that I just want to bring up again because I started to forget it. But I don't want people out there to forget it. You mentioned having multiple different coffees to compare and contrast multiple different beans. And I think that's really important, not just for what we're talking about today, but also tasting.
I want to point that out because usually I just have one or two coffees that I'm drinking at home, but for the purposes of learning and exploring topics like coffee defects, having several samples to compare [helps]. I can't speak for every coffee roaster, but if you go to your local coffee roaster and say, Hey, do you have any old coffees that I can just kind of play with and explore. Often, they might have something lying around or a few bags of something that they can give you that you can use to create baselines for your learning because you don't necessarily want to be buying a $25 bag of coffee and then smashing it all up and not actually drinking it, just exploring it. That's just me. You can tell me if I'm crazy for saying that.
Alden: I think that's fabulous. You know, at Crossings, one of our fundamental ethos is education and demystification. We want people to learn so they can be more informed and make more informed decisions about the coffee that they buy in the drink. I can't say that every roaster is going to do that.
I'm not going to shame any roaster if that's not their mantra, but I would say any roaster, you know, worth their salt, who is also invested in the knowledge and education of their own consumers, they would be happy to encourage whatever learning or exploratory ventures that consumers want to go on.
R!WC: We still have like two minutes. You wanted to be ambitious. So, what about green beans?
Alden: Green beans, so if you're a home roaster and looking to get into roasting, some things you want to look out for are gonna be really visually obvious. If you see a bean that has chips in it, it's got cracks on it, it's got a lot of discoloration. Those are things we do not want to see. If you've got a bag of coffee, and you're seeing rocks and twigs and sticks, that could be an indicator of poor sorting at the farm or a lack of resources to afford better sorting at the farm. If you see beans that are a variety of really tiny peaberries and then larger ones, that could be another sign of bad sorting or mislabeled beans. If you know, it's supposed to be all one variety, the color of the bean. If you've got some that are blotchy and reddish or some that are off in different colors, that could be the result of poor fermentation or drying methods.
And as I'm saying, that's an extra remembering one other visual cue I'd like to offer consumers for their at-home roasted coffee. You can look on Google to see what a coffee bean looks like. Everyone knows what a coffee bean looks like. But if you're getting ones that have like a seashell-looking effect, or they're looking twisted, or they're missing chips, and they've got holes and things like that, those are also indicators of poor nutrition, poor harvest malnutrition, as the beam has been developed, maybe there was like some bug infestations, you get little bugs that like kind of burrow into the bean. And these get roasted like they're, they're not dangerous to drink, but they can produce off flavors in your cup.
R!WC: Gross. Now quick recap. Then what's our one-sentence breakdown? What do we want to leave the audience with today?
Alden: The more consistent your bean looks in the bag or in your hands, I think that's an indicator [you'll get a] better cup. If you're seeing a lot of variety, a lot of different shapes, sizes, colors, textures, that could be a red flag for an off-crop. But there's only one way to tell. You got to taste it.
R!WC: Alden. Until next month, I'm looking forward to learning more. We should do this more often than every month. I'm going to talk to you about that offline.
*This transcription has been edited for length and clarity.
WHERE YOU CAN FIND CROSSINGS COFFEES
Online! Click to shop CrossingsCoffee.com
San Diego-area vendors include: Plus Six One mobile cafe, Wayfarer Bread, Cafe La Terre, Mesa Rim Climbing Gyms
MORE ALDEN:
Alden has been on the R!WC podcast before. He often appears on Coffee Smarter. Check out this episode on building an efficient coffee bar ft. his three pillars to live by: kindness, community, and the pursuit of excellence.
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