I’m not sure I’m going about things the right way, but I’m taking what I have learned from Robb Hoos and Morten Munchow and am aiming for specific roast goals with as few adjustments as possible. I am trying to hit specific Yellowing, 1st Crack, Dev Time, and end temp for light, medium, and dark roasts on 850g, 600g, and 350g batches.
So for example, I just took a few stabs at a “dark” roast of 850g with the aim of five minutes for yellowing, ten for 1st crack, around three minutes of development time, with an end temp of around 420 - 425 degrees F. I’m not expecting this to be the perfect roast, but I’d like to learn how to control my roaster with this starting point in mind for a dark roast (9 FC and 2 min dev, end temp 410F for medium) and make adjustments for taste as I get more comfortable.
I was able to just about hit every marker for the last of three roasts but on each roast I was not able to hit the end temp I was looking for. I was low each time, even on a relatively long roast. I guess what I’m not understanding is how much that matters. If my weight loss is about 16% and I’ve hit the other markers I was aiming for, does end temperature really matter? I’m sure it does, but would love to hear thoughts on this.
Just to clarify by “I was not able to hit the end temp I was looking for” are you saying you’re not able to hit the 420-425F after 2 mins of dev time after FC? Or something else?
If your roast profiles are public post the links to the ones you were having trouble with would be helpful. My “knee jerk” question is “what’s your PH temp for this 850g batch?”
In brief, if you were looking for 420-425, I don’t see 414 as missing the mark, because that’s what it says your end temperature was. If you want to reach your goal, either increase PH or go to P9 at the beginning of the roast. The end temperature, as Münchow says, isn’t that important. Reaching your desired colour and development is. He also explains how to reach the same colour with different end temperatures. And what you get in the quiz, if you take his course, are the questions about what’s important to reach the desired colour, not desired end temperature. More time is spent on what adjustments you need to make if your end temperature is different to match the colour, than on the end temperature itself.
Blacklabs, yes, I roughly hit the ten minute first crack mark with three minutes development, but ended at 414 IBTS. On the first two where I was behind on targets my PH temp was 508. P7 for the first and P8 for the second. I was going by Rob Hoos’ advice to PH lower for longer, dark roasts. For the last one where I was just a bit behind, but close, I bumped up to 536 PH with P8.
Braca, I took the Munchow course and yes, you are right, but I’m not great at visually gauging color due to lack of experience and also I’ve always been bad at matching colors on PH strips or water testing strips so I’ve been relying on weight loss. So I’m thinking that if I’m above 16% weight loss then I can probably count that as a “dark” roast despite not hitting the end temp. Also, Munchow says that you can lower your expected end temp with longer roasts so I’m taking that into consideration. I think I will try either a higher PH or power setting next time just to see what happens.
No worries, I’ve looked at them all the same. By the way, if you haven’t seen this, and you have some spare time, it’s a great solution for colour. Start from here and read on.
@ferg so yes start with a higher PH. For my 1kg my PH is 572F with F1 and P7 or P6 for the first minute then I crank that up to P8 or P9, with D7 for that first 2 to 3 mins before going to D8 for the rest of the roast. I do adjust the F and P as I go along and usually end my roasts between 410 and 435 depending on how dark I’m looking to roast. Feel free to take a look at my roasts (I haven’t roasted in the last 4 months because I fractured my foot, still in rehab). But main thing is get enough PH in the drum to get the momentum going for a larger batch. (to give credit where it’s due, I learned my initial 1kg roasting by studying @cash0612 1kg profiles and then made my own tweaks from there )
blacklabs , to whom I wish a speedy recovery, has already said much more than I could ever say about dark roasts. My opinion of them is that they’re just like overcooked or overseasoned food. But I will tell you this. Don’t look so much at the profiles of others since all of us live in different places. Different elevation, humidity, temperature etc. Do look at them to have a starting point as blacklabs suggests.
Also, weight loss will not tell you much. Now, this is my first roast of this Bolivian and it tells me what adjustments I need to make. As you’ll notice, the weight loss is 14.2% and the roast is far lighter than I wanted it to be. Almost a 100 on Agtron gourmet and 27 on Roast Vision.
I am sorry, but it’s colour, colour and colour, as the three most important factors. Don’t be too worried about not doing everything right because you’ve only got 24 roasts under your belt. Patience and practice will get you where you want to be. One other thing I almost forgot to mention is your roast12. Don’t try to beat the crack and crash down as you did there. You came down from P7 to P4 and up from F4 to F6 in less than a minute. That’s what I’d try to avoid if I were you. And remember, these are just other people’s opinions that are only there to help you a bit in creating your own. Happy roasting.
This is incredibly helpful. Thank you both! I’m sorry to hear about your foot, blacklabs. Hope you get better sooner than later! So, sounds like WL is more useful when matching certain roasts, rather than as an indicator of roast degree. This is good to know. And yes, Braca, R12 was definitely a reactionary roast and I appreciate the feedback. This has proven to be a great community, and for that I am thankful.
Yes to color - use the trier to inspect the color don’t rely on viewing thru the little window, and also smell of the beans. If you were to roast “blind” (meaning without the software) you’d be relying on site, smell and to an extent sound (for the FC and SC). This is what I had learned many years ago taking a roasting class from a pro on a 12kg gas fired Probat - we didn’t use software in that class, just pen and paper, and the watch/timer.
Just remember in the end it is about whether you enjoyed your roasting results. You can have a beautiful or perfect “curve” but a crappy cup.
@blacklabs of late, I have added a soak to my roast. That has taken care of the tipping that I was having some times. Meanwhile, have changed my pre-heat temps for B2B roasts too. For the first two, I do 300C, then 295 for the next two and then 290 for the last one. Meanwhile, as of now, I’m aiming for a 5-minute Maillard, 2-minute (medium) and 3-minute (dark) for Development. Since I have to deal with uneven bean moisture, the Yellowing time tends to vary but after hitting Yellowing (which I mark at 160C), the Maillard and Development phases are pretty uniform across the roasts.
My target is Temperature based but achieved within those time targets. The coffee has improved quite a bit with this new regimen.
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