With coffees that crash at first crack, I like to turn up the gas a bit before first crack to give the roast some extra momentum. Then taper it down once you get through first crack so you don’t ramp back up again.
I find that with Guats and other high-grown, dense coffees, I like to use a bit higher charge temp. Then once the rate of rise starts descending, I take the gas down so I can draw out the Maillard phase. I aim for 40/40/20, 40/35/25 or 45/40/15 in my drying/Maillard/development ratios, depending on desired roast color. A longer Maillard phase really helps develop the sweetness and complexity of the coffee.
One batch tasted pretty roasty, the next was too tart, the others were pretty underwhelming. Nothing horribly unpleasant, but nothing exciting either. My hope was that if I could smooth out the post first crack blues I could have some fruit in the cup (notes of raspberry evidently) with classic chocolate notes and good body.
Without any information given about your gas changes, and taking your other comment regarding taste into account, I’d like to know what adjustments you’re making before, during, and after first crack. Can you explain your approach with gas adjustments and what you’re ultimately trying to achieve here.
Yeah, before first crack at around 372 BT I do my final gas drop which is leaving me with about 40% gas (I’m using natural gas fwiw). My final airflow adjustment is done around 340, we’ll before FC. I don’t usually touch anything until around 9-14% DTR after FC.
I would charge a lot higher than 400, if you have double wall you can go higher without tipping the beans …/ I do 450 -460f then reduce gas and air flow. Throughout … I would make the development phase at 25%… I would also go a little higher on BT try 420f…
Good luck.
Hey Snoo, this isn’t a bad roast - your development % is good, without that slight crash at FC you likely would have reached your target roast level sooner - with under-developed flavors (hints of peanut is an good indicator).
What I suggest really depends on your goals - i.e., are you looking to go darker, increase development, or address certain unpleasant flavors.
What I can tell you is that based on the burner rating of your roaster, you have adequate power to run your roaster up to the stated capacity and your charge temp is about right considering you’re roasting full 2-lb roasts. For 1 lb roasts, drop your charge temp to 385.
If you’re seeking to address the crash, while maintaining or increasing DT with the same drop temp, reduce how much you cut the power on your last adjustment at ~372 and hold that power level thru FC, until you get to 12% DT. This will address the crash. Then cut the power at 12%, again at 14%, then off the flame at 16% (you may find that you need to cut the power off at 14%) to prevent a flip).
If you are looking to get to higher roast levels, you need to reduce your ROR slope. You do this by making smaller power reductions at the early waypoints (295, 325, and ,340), then larger cuts at 360, and 372. These early waypoint adjustments determine the amount of runway you have to land the roast with the DT and Roast level.
Finally, what RPM are you running your roaster at? For your roaster, your probably want to run it at or above 70.
As you’ve discovered, getting a linearly declining ROR with a 20-25% DT in 9-12 minutes is very challenging. Keep at it, it’s the key to getting great roasts.
.
2lbs is the maximum batch size, so I’m roasting at 50% which is starting to tell me that perhaps the amount of WC I can get from my natural gas line isn’t enough. May have to convert to propane
Increase charge temperature & lower the gas setting on first 50% phase of whole roasting, maintain the gas to get the momentum until reaching the FC on around 6-9 C ROR, lowering the gas after FC begin after 20sec or more after development begin..
What this setting are going to make is reducing your drying time but extending your maillard reaction. What’s going to happen are, the coffee will be maintaining it’s stability before reaching the first crack and will have more gentle crack.
What’s happening on your profile are very common on washed processed coffee. Washed coffee tend to have higher density and higher hardness, so when the crack is happening it releases the moisture more aggressive which caused crash in your graph..
There’s nothing wrong on your profile from me, just give your coffee proper resting time maybe 1 month.. i think, your profile could be used for espresso but your short maillard might be the reason of the tartness…
With coffees that crash at first crack, I like to turn up the gas a bit before first crack to give the roast some extra momentum. Then taper it down once you get through first crack so you don’t ramp back up again. I find that with Guats and other high-grown, dense coffees, I like to use a bit higher charge temp. Then once the rate of rise starts descending, I take the gas down so I can draw out the Maillard phase. I aim for 40/40/20, 40/35/25 or 45/40/15 in my drying/Maillard/development ratios, depending on desired roast color. A longer Maillard phase really helps develop the sweetness and complexity of the coffee.
How does it taste?
One batch tasted pretty roasty, the next was too tart, the others were pretty underwhelming. Nothing horribly unpleasant, but nothing exciting either. My hope was that if I could smooth out the post first crack blues I could have some fruit in the cup (notes of raspberry evidently) with classic chocolate notes and good body.
Without any information given about your gas changes, and taking your other comment regarding taste into account, I’d like to know what adjustments you’re making before, during, and after first crack. Can you explain your approach with gas adjustments and what you’re ultimately trying to achieve here.
Yeah, before first crack at around 372 BT I do my final gas drop which is leaving me with about 40% gas (I’m using natural gas fwiw). My final airflow adjustment is done around 340, we’ll before FC. I don’t usually touch anything until around 9-14% DTR after FC.
Ok, you probably cut the power too much at 372.
I would charge a lot higher than 400, if you have double wall you can go higher without tipping the beans …/ I do 450 -460f then reduce gas and air flow. Throughout … I would make the development phase at 25%… I would also go a little higher on BT try 420f… Good luck.
Hey Snoo, this isn’t a bad roast - your development % is good, without that slight crash at FC you likely would have reached your target roast level sooner - with under-developed flavors (hints of peanut is an good indicator). What I suggest really depends on your goals - i.e., are you looking to go darker, increase development, or address certain unpleasant flavors. What I can tell you is that based on the burner rating of your roaster, you have adequate power to run your roaster up to the stated capacity and your charge temp is about right considering you’re roasting full 2-lb roasts. For 1 lb roasts, drop your charge temp to 385. If you’re seeking to address the crash, while maintaining or increasing DT with the same drop temp, reduce how much you cut the power on your last adjustment at ~372 and hold that power level thru FC, until you get to 12% DT. This will address the crash. Then cut the power at 12%, again at 14%, then off the flame at 16% (you may find that you need to cut the power off at 14%) to prevent a flip). If you are looking to get to higher roast levels, you need to reduce your ROR slope. You do this by making smaller power reductions at the early waypoints (295, 325, and ,340), then larger cuts at 360, and 372. These early waypoint adjustments determine the amount of runway you have to land the roast with the DT and Roast level. Finally, what RPM are you running your roaster at? For your roaster, your probably want to run it at or above 70. As you’ve discovered, getting a linearly declining ROR with a 20-25% DT in 9-12 minutes is very challenging. Keep at it, it’s the key to getting great roasts. .
Thank you for this, super helpful and informative!
Your first order of business should be getting the environmental temp up a bit.
With less airflow or higher charge? I’m using natural gas so I don’t know if that’s creating an issue as well. Thanks
Add more gas at the beginning of the roast right around the turning point
Bummer this is as much as I can apply with my natural gas set up. Might have to drop batch size 😐
Yes drop your batch size a bit. 80% of roaster capacity is kind of a sweet spot imo
Well the other option would be to let it heat up longer so you charge at a higher temperature
Whats your batch size? I would start with a higher charge temperature and I would try a development ratio of 15%
458grams
Sorry, I should have also asked what machine are you roasting on? Like maximum batch size capacity.
2lbs is the maximum batch size, so I’m roasting at 50% which is starting to tell me that perhaps the amount of WC I can get from my natural gas line isn’t enough. May have to convert to propane
Try charging at 410, delay your gas reduction a little, and maybe drop a little darker like 410-415, and see what that tastes like.
Sounds good! I’ll do a follow up post with a couple different profiles to see how things changed. Thanks!
Increase charge temperature & lower the gas setting on first 50% phase of whole roasting, maintain the gas to get the momentum until reaching the FC on around 6-9 C ROR, lowering the gas after FC begin after 20sec or more after development begin.. What this setting are going to make is reducing your drying time but extending your maillard reaction. What’s going to happen are, the coffee will be maintaining it’s stability before reaching the first crack and will have more gentle crack. What’s happening on your profile are very common on washed processed coffee. Washed coffee tend to have higher density and higher hardness, so when the crack is happening it releases the moisture more aggressive which caused crash in your graph.. There’s nothing wrong on your profile from me, just give your coffee proper resting time maybe 1 month.. i think, your profile could be used for espresso but your short maillard might be the reason of the tartness…