From the Lab, Resources for Roasters
Monday, November 29, 2021
Scaling Up on Roasters
When it's time to scale up from your sample roaster to production roasting, there are some keys to maintaining consistency and quality in your roast. James McKenney, Specialty Sales Trader & Q Grader, has 6+ years of experience working at roasteries of all sizes and he’s here to share his experience of scaling up from sample to production roaster.
The first thing to do after you’ve purchased your coffee and are ready to scale up is roast the coffee using several profiles on your sample roaster, James explains. “If your sample roaster has the ability to adjust temperature, and air flow, play around a bit.” Keep the profile differences very simple and measurable, such as higher/lower charge temp and longer/shorter development time. Need some guidance? Our fabulous QC team has written about basic profiles on the sample roaster, you can read more about that here.
When you purchase a coffee, you typically have an idea of where it will sit in your lineup. Roasting a few batches on the sample roaster helps realize those plans without wasting precious green coffee.
Not quite sure where to start? There are some basic guidelines for which coffees work well for different roast profiles and different uses. You can use those as a guide so you’re not running all over the place. Regional Central American and South American coffees often work very well for a medium to dark roast and are a good base for espresso blends. Higher elevation, higher density coffees from Central & South America, East Africa and elsewhere are generally seen as better suited for a lighter roast, because that accents their often inherently sweeter, more delicate flavors.
“Having all that information in your head will give you a guiding framework for what you’d like to start doing with any coffee that you buy. From there, I would go to trialing sample roasting profiles, cupping them side by side to see which of the roasts you did is most conducive to getting what you want,” James says. If your sample roaster has limited modulation, at the very least you should roast a basic roast profile, cup it, and make note of which elements you would like to bring out in the production roast. From there you can go into the production roast with an idea and plan.
Cupping is Essential
Once you’ve tried roasting a few sample profiles, cup them with an eye towards the finished product. “Cupping is essential to this entire process, and also to getting better at roasting in general. It’s critical to cup your production roasts, take notes and evaluate what you’re roasting,” James says.
When cupping, evaluate whether the roast profile is highlighting or masking the qualities that you want in the end result. “For example, people will often mix a Colombian and an Ethiopian together to make a blend. When you’re doing the sample roast and cupping it, you want to make sure that you’re really getting the floral, citrusy, sometimes fruity ‘high notes’ out of the Ethiopian coffee that you would probably want in the blend. Out of the Colombian, you want to make sure you’re getting the chocolatey notes and rounded body - and body is very much tied in with how you roast the coffee,” James explains. “The same rules apply for a single origin offering, though it’s less complicated because you really just need to bring out the best qualities of that coffee.”
Something a lot of people don’t think about but is a big consideration for blends is balance. “If you bring out everything that’s good in all the coffees going into the blend, it can produce something that’s convoluted and that has all these competing elements,” James says. “Sometimes, you actually want to mute or mask specific elements so the two or three coffees can do well together.”
Scaling Up for Production
After cupping these samples, it’s time to apply your profile to a production roaster. Sample roasting should get you to a point where you have a rough understanding of how the coffee will react in the roaster and what you’re going to try to do to the roast. The next step is making sure you have some production roast templates before going into the roast.
At the very least, have an espresso and filter roast profile for your production roaster that you try to follow. More ideally, you’d have a regional profile that shows you what you normally do with coffees from that region. If you wanted to get a little more in depth, it’s probably good to have profiles that take into consideration the density and size of the bean, because that’s going to be a pretty big contributor to how it roasts. “If you acknowledge that the coffee that you’re working with is similar in some form – flavor, density, size – to coffees that you’ve previously roasted and had success with, that’s going to save you a lot of trouble,” James says.
If you’re new to roasting, there are so many resources on roast profiles that you can reference. However, “I think it’s important that when you’re researching profiles, you take the information as a general guide. Every machine is different and they work differently in different instances. Take the information but understand that it’s not going to work exactly the same way for you, which is also the reason we’re not giving exact information in this article. It’s good to take a varied approach and make it your own,” James says.
Cup, and Cup Again
The next step is the most critical one. You’ve just bought an Ethiopian from us. You’ve roasted a similar coffee previously or found the resources online for a general Ethiopian roast profile. The most important next step is that you roast it to the best of your ability and that you cup it as soon as you can.
Getting better at roasting is constantly cupping what you’re roasting. It’s critical to cup your production roasts, take notes and evaluate it. When you’re cupping, actively consider the roast profile while you’re cupping. “Not just what’s in the cup, but how it got there and what do I need to change in the roast to get the desired effects?” James explains.
Scaling up is a key part of purchasing and roasting new coffees. When you follow these steps, you’re more likely to get an acceptable roast the first time you try, and - just as importantly - an idea of the changes you’ll need to make to hit your target. If you’re still struggling, James recommends that you check out more resources, including all those we have on our website! A good understanding of roast variables on your roaster will really help to guide your decisions. Also, get a second opinion- don’t cup in a vacuum! Having someone who can give you good honest feedback will go a long way. Maybe your profiles are working better than you think. Finally, keep it simple! If you’re struggling, stick to basic, proven roast profiles, and only change one variable at a time. Whatever your question or need, our traders are here to help you, so don’t hesitate to get in touch if you have any questions.