Re: My First Roast
Hiya Sen.... 
Those black holes you have noticed on some of the beans are generally referred to as "Divots".
While your lead up to FC looks to be very close to ideal, Id say you didnt reduce the heat enough when FC got a roll on. The thing you need to be aware of with this stage of the roast, the beans actually become exothermic. That is, they produce more heat than they actually absorb. Thats where thermo logging comes in handy as you can actually see this happen and then reduce the heat appropriately so as to produce a gradient that rises only about 1-2C/Minute during Rolling FC. As you hear the roll slow down you can increase the heat again slightly to a gradient of about 3-4C/Minute which should put you on target for the first few crackles of Second Crack(SC) about 5 or so minutes later.
The reason for the appearance of Divots on a few beans is because of too quick a rush into SC and is reasonably well solved by adopting a profile similar to that described above. You may still notice the occasional bean here and there with a Divot but that is not really anything to worry about. Coffee Roasting is a continuous learning experience, no doubt about that and I believe that is what makes it so much fun.....
All the best,
Mal.
Originally posted by 63555E51445F42300 link=1251506699/13#13 date=1251586808

Those black holes you have noticed on some of the beans are generally referred to as "Divots".
While your lead up to FC looks to be very close to ideal, Id say you didnt reduce the heat enough when FC got a roll on. The thing you need to be aware of with this stage of the roast, the beans actually become exothermic. That is, they produce more heat than they actually absorb. Thats where thermo logging comes in handy as you can actually see this happen and then reduce the heat appropriately so as to produce a gradient that rises only about 1-2C/Minute during Rolling FC. As you hear the roll slow down you can increase the heat again slightly to a gradient of about 3-4C/Minute which should put you on target for the first few crackles of Second Crack(SC) about 5 or so minutes later.
The reason for the appearance of Divots on a few beans is because of too quick a rush into SC and is reasonably well solved by adopting a profile similar to that described above. You may still notice the occasional bean here and there with a Divot but that is not really anything to worry about. Coffee Roasting is a continuous learning experience, no doubt about that and I believe that is what makes it so much fun.....

All the best,
Mal.

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