Hi James,
It can get really frustrating when you know something is wrong but don't know how to fix it........... I speak from experience!
I have only used a Gene and now a commercial 5kg but looking at your graphs and pics would like to offer some thoughts.
1. Don't get caught up with fixed ideas from what you read or what others with different gear/setups experience. Every roast situation is unique, find what works for you. Be more flexible and experiment.
2. If you look at your last profile and the one supplied by Matt there are a couple of obvious differences. Both profiles are measuring from a cold start but if you take 50* as an actual start point for the roast then your profile is running approx 8 minutes to 1st C and Matt's 11.
Even though your third profile looks better than the first two the approach is still quite aggressive. The tipping obvious in your photo will be coming from this aggressive early ramping where the germ end of the bean dries out faster than the rest and then over roasts towards the end of the cycle. The other factor involved with tipping will be the rate of agitation; if the beans are in the heat stream or contacting hot parts of your roaster for too long, tipping will occur. Scorching (different from tipping) later in the roast may also happen. The other difference is ratios; your time to 1st crack is approx half your total roast time (from50*) Matt's is more like two thirds to three quarters.
3. Try and achieve a roast profile that is more radically different than the three you have posted to give you some broader parameters to tweak. Everything is a bit too same same at the moment. Try to shorten the time between 1st and 2nd crack as mentioned by Andy previously. Currently it's about 8 minutes, bring it back to 4 (6 at the most).
4. A bit hard to tell from your pics so I might be wrong but if you remove some beans after first crack and well before second look for centreline charring. This comes from too much applied heat between bean drying (about 150*) and 1st C.
5. Don't give up! I have thrown out a mountain of beans and with perseverance and sage advice from the grand poo-bah I'm almost there.
6. You are really close to achieving great results.
It can get really frustrating when you know something is wrong but don't know how to fix it........... I speak from experience!
I have only used a Gene and now a commercial 5kg but looking at your graphs and pics would like to offer some thoughts.
1. Don't get caught up with fixed ideas from what you read or what others with different gear/setups experience. Every roast situation is unique, find what works for you. Be more flexible and experiment.
2. If you look at your last profile and the one supplied by Matt there are a couple of obvious differences. Both profiles are measuring from a cold start but if you take 50* as an actual start point for the roast then your profile is running approx 8 minutes to 1st C and Matt's 11.
Even though your third profile looks better than the first two the approach is still quite aggressive. The tipping obvious in your photo will be coming from this aggressive early ramping where the germ end of the bean dries out faster than the rest and then over roasts towards the end of the cycle. The other factor involved with tipping will be the rate of agitation; if the beans are in the heat stream or contacting hot parts of your roaster for too long, tipping will occur. Scorching (different from tipping) later in the roast may also happen. The other difference is ratios; your time to 1st crack is approx half your total roast time (from50*) Matt's is more like two thirds to three quarters.
3. Try and achieve a roast profile that is more radically different than the three you have posted to give you some broader parameters to tweak. Everything is a bit too same same at the moment. Try to shorten the time between 1st and 2nd crack as mentioned by Andy previously. Currently it's about 8 minutes, bring it back to 4 (6 at the most).
4. A bit hard to tell from your pics so I might be wrong but if you remove some beans after first crack and well before second look for centreline charring. This comes from too much applied heat between bean drying (about 150*) and 1st C.
5. Don't give up! I have thrown out a mountain of beans and with perseverance and sage advice from the grand poo-bah I'm almost there.
6. You are really close to achieving great results.

but considering the variation between individual beans and the way the beans seem to be charred inside I am trying to understand if this is related to the beans themselves or if I am doing something wrong - what do you guys think? I am getting very sour notes, intense bitterness and a dull baked & woody flavour.
Which doesn't really make sense to me just yet, but I'll try a different profile and see how it goes. While I have no experience with roasting, the unevenness and the way the beans are on the inside make me instinctively wonder if this is an old dry bean that got some recent superficial humidity in the Auckland weather, or whether it's just how this particular bean behaves. Do you get this unevenness in your corretto process around the 1st crack?
...
Comment