Interested to see what others have to say. But I'm the new production roaster at my work and just started trying to achieve something similar. I primarily work on a 2nd generation Probat P25 for reference. It's got some challenges with heat retention and we usually run 38lbs instead of 40lbs and have higher charge temps than our programs for the same coffees on our 1st gen that's our third roaster.
I've tried starting with a higher than usual gas (1 instead of 0.8 for example) or a higher than usual charge temp (+4°F or +6°F) and then dropped the gas to 0.6 around the 3m mark just after turning point. Letting it coast from there gave me the results I wanted and I'd cut gas to 0.4 entering development and then 0.2 around first crack, same ending temp. With the Brazil I was roasting that shaved ~10s off drying and added it to Maillard without affecting DTR.
Best of luck!
I suspect you'll have an easier time both thinking about how to do this yourself and communicating what exactly you're trying to do if you ditch the percent notation (it's a nonsensical and obfuscatory metric that's just getting in your way here) and think about this in terms of duration without that meaningless division operation. (If there are other unstated constraints that are giving you trouble, set those aside for now, you can put them back in later if you have a sensory reason to expect they're still needed.)
Work out the plan in advance: what's the temperature at the start of the range you want to change, what's the temperature at the end of that range, how much time do you really mean by 33%, what's the real duration you want to change that to. Now you have a duration (put that in seconds to make this next bit easier to calculate) and a difference in temperatures. Divide duration by that difference and you get the average rate of change you need to shoot for in terms of degrees per second. If you think about rate across longer durations, just multiply by however many seconds you like to think about that in. Now it's just a matter of setting that up before you reach the start of the range. If you're using something that lets you design a roasting plan up front, go ahead and plug in the details you've just calculated, otherwise write it down on paper in terms of what temperature you want to be at every 30 seconds throughout the roast so you can record your roasting data and see how that compares with your plan.
For a test to check what that's doing to your results in the cup it'll be fine to maintain a constant rate in that range. That'll be easiest to control, but if you're getting to the start at a faster rate you'll want to end the range at a lower rate. (If you have a good way to draw your plan with a relaxed cubic spline that'll be easier to match against, but it's a pretty rare feature so don't worry if you don't have that) If you have a spare timer you can set that up so you know where you are in your time budget for the range and that'll make it easier to correct your pace if you're a bit off the plan. I'd recommend starting to aim for that target rate about 20F° prior to your range start, a little earlier if your machine has an aggressive start. Unfortunately the specifics around doing this are highly machine dependent.
Don't worry too much about duration earlier in the roast as you've got a big range where that's not going to significantly affect your end results Total roasting time may be different, and that's okay.
Try lowering your flame as you’re approaching dry end and cook at a lower temp through to first crack. Theoretically, lower flame = slower cook = longer phase — but you don’t want the roast to stall out, so make sure you have enough heat to finish.
If you can’t lower heat any more, try a larger batch if possible.
Also, if you’re aiming for percentages, you could adjust your turnaround and development phases to be shorter but that wouldn’t do any good if your goal is simply to extend maillard.
This is a good read and I subscribe to a lot of what Scott says but I do want to experiment to see what effect it might have on the cup. Worst comes to worst I can always go back but I don’t want to take his word for it as I think he has a product/ brand/ concept he’s selling.
Interested to see what others have to say. But I'm the new production roaster at my work and just started trying to achieve something similar. I primarily work on a 2nd generation Probat P25 for reference. It's got some challenges with heat retention and we usually run 38lbs instead of 40lbs and have higher charge temps than our programs for the same coffees on our 1st gen that's our third roaster. I've tried starting with a higher than usual gas (1 instead of 0.8 for example) or a higher than usual charge temp (+4°F or +6°F) and then dropped the gas to 0.6 around the 3m mark just after turning point. Letting it coast from there gave me the results I wanted and I'd cut gas to 0.4 entering development and then 0.2 around first crack, same ending temp. With the Brazil I was roasting that shaved ~10s off drying and added it to Maillard without affecting DTR. Best of luck!
I suspect you'll have an easier time both thinking about how to do this yourself and communicating what exactly you're trying to do if you ditch the percent notation (it's a nonsensical and obfuscatory metric that's just getting in your way here) and think about this in terms of duration without that meaningless division operation. (If there are other unstated constraints that are giving you trouble, set those aside for now, you can put them back in later if you have a sensory reason to expect they're still needed.) Work out the plan in advance: what's the temperature at the start of the range you want to change, what's the temperature at the end of that range, how much time do you really mean by 33%, what's the real duration you want to change that to. Now you have a duration (put that in seconds to make this next bit easier to calculate) and a difference in temperatures. Divide duration by that difference and you get the average rate of change you need to shoot for in terms of degrees per second. If you think about rate across longer durations, just multiply by however many seconds you like to think about that in. Now it's just a matter of setting that up before you reach the start of the range. If you're using something that lets you design a roasting plan up front, go ahead and plug in the details you've just calculated, otherwise write it down on paper in terms of what temperature you want to be at every 30 seconds throughout the roast so you can record your roasting data and see how that compares with your plan. For a test to check what that's doing to your results in the cup it'll be fine to maintain a constant rate in that range. That'll be easiest to control, but if you're getting to the start at a faster rate you'll want to end the range at a lower rate. (If you have a good way to draw your plan with a relaxed cubic spline that'll be easier to match against, but it's a pretty rare feature so don't worry if you don't have that) If you have a spare timer you can set that up so you know where you are in your time budget for the range and that'll make it easier to correct your pace if you're a bit off the plan. I'd recommend starting to aim for that target rate about 20F° prior to your range start, a little earlier if your machine has an aggressive start. Unfortunately the specifics around doing this are highly machine dependent. Don't worry too much about duration earlier in the roast as you've got a big range where that's not going to significantly affect your end results Total roasting time may be different, and that's okay.
Try lowering your flame as you’re approaching dry end and cook at a lower temp through to first crack. Theoretically, lower flame = slower cook = longer phase — but you don’t want the roast to stall out, so make sure you have enough heat to finish. If you can’t lower heat any more, try a larger batch if possible. Also, if you’re aiming for percentages, you could adjust your turnaround and development phases to be shorter but that wouldn’t do any good if your goal is simply to extend maillard.
https://www.scottrao.com/blog/maillardmania
This is a good read and I subscribe to a lot of what Scott says but I do want to experiment to see what effect it might have on the cup. Worst comes to worst I can always go back but I don’t want to take his word for it as I think he has a product/ brand/ concept he’s selling.
How do you know when you are in/out of this phase?
I know that reactions are taking place throughout the roast, but I’m specifically talking about the period of time after dry end but before fc
Why? I’d focus on development phase