Replies to This Discussion

Permalink Reply by John Battaglia on November 13, 2008 at 3:43pm

How long is your roast?

Permalink Reply by Matt Higgins on November 25, 2008 at 2:38pm

I wish I could state that you can find a way around it, however in my experience you probably will not, simply because of your batch size. Assuming your french roast is pretty dark, somewhere within the 450-460F range, your going to be dealing with a lot of stored heat potential.

Your roasting around a 60kilo mass of agricultural material that stores a lot of potential heat energy through the roast, as you near 2nd crack that mass is going to want to go very exothermic, even if you cut flame entirely I still think they would ramp up in your drum to the point of "blowouts".

With that said, a smaller mass in a smaller roaster would be much more controllable within those temperature ranges because there is less mass to go "exothermic", therefore the beans could approach a "french roast" much more gently and with fewer blowouts.

I think you will have trouble trying to be as gentle as you can with 60kilos at such a high temp. Just save that practice for your coffee's other than those from daniel petersons estate lol.

Just my two cents,

Also, I myself do not practice "french roasting", to me its a roasting practice that will never hallmark the true flavor characteristics of a coffee, at that roast level you are "carbonizing" the beans and inserting false body and destroying the delicate chains and acids formed by a correct profile, taking it darker will destroy that work.

But hey, it does sell, ..... so I understand its place, this is after all a business.

Permalink Reply by b smyth on November 26, 2008 at 9:53am

something dense and beady, i'd reckon... I'm pretty sure the beans i'm using now are far too delicate for the punishment of a long, drawn out 3rd crack hell... if i had my pick i'd use Costas or Colombians ...some panamas i've roasted are also durable as hell

Permalink Reply by b smyth on November 26, 2008 at 10:04am

Thanks Matt - this was helpful. I decided to french a roast on the 15 kilo to see if there was a difference in the momentum of mass / number of chips and blowouts... the 15k had far fewer blemishes.

on the 60k i've tried cutting the temp right before the 2nd and resting it, in hopes of taming it, but I end up with lighter colored french and lighter colored chips. after a few dozen batches of experimenting i've decided that there is no way around much of it - although you can limit the damage, you also can't dick around with drawing a french out too far / cool

thanks again for your insights


Matt Higgins said:

I wish I could state that you can find a way around it, however in my experience you probably will not, simply because of your batch size. Assuming your french roast is pretty dark, somewhere within the 450-460F range, your going to be dealing with a lot of stored heat potential.

Your roasting around a 60kilo mass of agricultural material that stores a lot of potential heat energy through the roast, as you near 2nd crack that mass is going to want to go very exothermic, even if you cut flame entirely I still think they would ramp up in your drum to the point of "blowouts".

With that said, a smaller mass in a smaller roaster would be much more controllable within those temperature ranges because there is less mass to go "exothermic", therefore the beans could approach a "french roast" much more gently and with fewer blowouts.

I think you will have trouble trying to be as gentle as you can with 60kilos at such a high temp. Just save that practice for your coffee's other than those from daniel petersons estate lol.

Just my two cents,

Also, I myself do not practice "french roasting", to me its a roasting practice that will never hallmark the true flavor characteristics of a coffee, at that roast level you are "carbonizing" the beans and inserting false body and destroying the delicate chains and acids formed by a correct profile, taking it darker will destroy that work.

But hey, it does sell, ..... so I understand its place, this is after all a business.