Roasting Strategies with BT/IT Profiles: What You Need to Know
In 2023, we announced a new way to control your ROEST sample roaster: the Bean/Inlet Temperature (BT/IT) profile. If you’ve been wondering how to get the most out of this feature, then help is at hand!
There are three resources to help you get started with the new profile type. Over on our YouTube channel, you’ll find an in-depth video all about BT/IT profiles from coffee-roasting expert Christopher Feran. On our support portal, we’ve published a step-by-step guide to designing and troubleshooting your profile. And finally, in this post, we share some tips on optimizing your profile, explain why BT/IT profiles are so powerful — and set you up with some sample profiles to start your journey.
BT/IT profiles are only available on machines equipped with an inlet temperature sensor — but if you haven’t upgraded your machine yet, you can use BT/Power profiles in a very similar way.
Expert insights on BT/IT profiles
To kickstart your journey with creating your own BT/IT profiles, we asked some of our early adopters to share what they learned roasting with this profile type.
Christopher Feran is a roasting consultant and green coffee buyer, based in Cleveland, Ohio, where he runs a roastery called Aviary. He was among the first to embrace the new profile type, and the BT/IT profiles that he has created spread rapidly throughout the ROEST community.
In his video, Christopher explains why he prefers roasting with BT/IT profiles and shares his tips to help new users get the most out of these profiles.
The BT/IT profile enables your ROEST sample roaster to automatically adjust the heat input based not on the roast time, but instead based on how far the beans have progressed in their roast.
This is similar to how an expert roaster traditionally controls the profile — by watching the bean temperature closely, and turning down the heat as the beans get closer and closer to the target temperature.
“This is how I actually approach roasting in a production environment,” Christopher says. “As a production roaster, we approach our adjustments to the roast based on what the bean is actually experiencing — in other words, we’re not trying to achieve a certain bean temperature, we’re making decisions based on the bean temperature.”
For this reason, the BT/IT profile is hands-down the most consistent way to roast your coffee. Even if the beans behave differently, your roast curve can adapt to them to give you the perfect result every time. “This is the type of profile that I use all the time,” Christopher adds.
Tips for designing your profile
Controlling your profile by temperature, instead of time, calls for a new approach when designing your profile. It can be hard to know where to start — we are so used to seeing profiles controlled by time, that designing a profile based on BT might feel like trying to think in four dimensions! But with the right strategy, creating a BT/IT profile doesn’t have to be difficult.
The easiest way to get started with BT/IT profiles, Christopher suggests, is to base your profile on an existing roast curve. Either choose a previous roast that you were happy with, or roast a batch in manual mode. Once you have established the basic shape of the roast curve you want to follow, you can use that data to build your profile. You can find a step-by-step guide on how to follow this approach in our guide to using BT/IT profiles on our support pages.
“Find a result that was successful for you,” Christopher says. “Observe the values for power or inlet at a given bean temperature, plot those against each other and build a profile that way.”
Meanwhile up in Montreal, Thibaut Paggen, the Managing Director of Apex Coffee Imports, has been using a similar strategy. “We roasted samples using a power profile and switching to manual mode. We started translating some of the best roast logs into a series of BT/IT profiles, and have been improving those since,” he says.
Once you have a baseline profile in place, it becomes much easier to understand how the profile controls the roast. “The most challenging part was to change our traditional roaster’s mindset about how to approach a roasting curve,” Thibaut explains. “Building profiles with temperature on both axes requires a little bit of brain gymnastics. But once you understand the relationship between both axes, it becomes almost self-evident and easy to manipulate.”
Using BT/IT for consistent roasting
As a green coffee importer, Thibaut’s team has to roast dozens of different coffee samples every day. BT/IT profiles are adaptable, which makes them the best way to approach a new coffee, he finds — but even so, one size does not fit all. “We have a series of 4–5 core BT/IT profiles crafted around density, moisture, water activity, and screen size measurements,” he says.
Christopher follows a similar approach, using different profiles depending on the processing method and moisture content of the bean. “Different coffees need different applications of heat, particularly before yellowing, at the start of the roast, when you’re working to drive that inner development,” he says. “Higher water activity coffees, and naturally processed coffees, will require higher energy at the start of the roast.”
If you don’t want to set up multiple profiles, another option is to use the same profile for all coffees, but to adjust the charge temperature depending on the coffee, Christopher suggests. This is an easy way to apply a little extra heat at the beginning of the roast for coffees that need it, such as those with a high moisture content.
Roasting with a BT/IT profile, of course, relies on having an accurate bean temperature reading. The bean temperature probe works best when it is fully covered with beans — which happens at batch sizes of 125 grams or more. With batches smaller than this, the bean temperature reading starts to be influenced by the surrounding air, Christopher points out. “It can be done at 100g, but you should know that you’re getting a lot more air in that thermocouple reading.”
Try BT/IT profiles for yourself
If you’re looking for a detailed guide on using BT/IT profiles, then head over to the user’s guide on our support pages. There, you’ll find guidance on when to use BT/IT profiles, and when another type of profile is a better option. We also give you some troubleshooting tips for developing your own profile.
If you just want to jump in and get started, however, then Christopher Feran has kindly agreed to share his standard BT/IT profile (named CF base profile) to get you started —you can find it on our Profile Library. If you use this profile, be aware that it is designed for Christopher’s specific machine, which has a few very specific settings, so you will need to make some adjustments to make it suit your own needs. “It’ll take some experimentation for you to figure out what works best for you,” he says.
“I do recommend you play with these profiles, you’ll find they’re extremely consistent,” Christopher adds. “It really is setting you up for much more success in evaluating your samples.”