How to Dark Roast in the Behmor 1600+

Consistently, the biggest complaint that we hear about the Behmor is that you “can’t roast coffee dark enough”.  With the safety features installed it can certainly be a challenge at times.  Here are a few quick tips to get you on your way: (Dark Roasting does have a risk of fire, and can damage your machine. Keep a fire extinguisher handy).

1. Lower your batch size - increase your batch setting.  Try roasting 8-10oz of coffee beans on the 1 LB setting, and it will be easier to roast darker.
2. Use the “C” button to extend your roasting time.  Once you get the hang of it, it is possible to do larger batches (we’ve done up to 20 ozs of green into 2nd crack).  One thing to keep in mind, is that you can press the C button multiple times to reset the roast counter.
3. Be sure to watch your “B” or chamber temperature.  Nothing is more frustrating than having your roast error 2, and not achieving the roast that you want.  You’ll want to dial back the heat if you get to 324 on the dial, usually dropping to P4 - 75% heat, and you can resume P5 - full heat once it goes back down to 318.
4. Clean - when dark roasting it is even more important to clean your machine.  Oil and soot buildup will make it more likely for your B temperature to top out, and also increase risk of fire.

Not sure what I’m talking about when I say “B” and “C”?  Read this post about the Behmor 1600+ controls

Now let’s dive into each of these tips to understand a little better the mechanics of what is happening in the roaster.  

Lower Batch Size - this one is fairly straightforward.  Our total heat output from the machine is constant, and with less mass to absorb the heat, it is easier to increase the temperature of said mass.  Or, we can make less coffee beans hotter with the same amount of heat.  We generally find that using lower batch sizes to get faster total roast times gives you a more pungent/strong dark roast.  Whereas, slower times can give you a smoother/softer flavor.  This tends to be true across roast degrees.  One other advantage of using smaller batch sizes is that you’ll see your exhaust (“A”) temperature, and chamber (“B”) temperature will read lower for the corresponding degree of roast. (i.e. with 10 oz of coffee beans my exhaust temp reads ~340 F at 1st crack, whereas with 13.5oz of green beans my exhaust temp reads ~355 at 1st crack).

Using the C button - or “C Hacking” - since the Behmor has a limit on the amount of time you can add using the + button, this feature comes in handy if you need to extend the roast time to reach the desired roast level. One often overlooked aspect is, you can press the button multiple times and it will reset the counter to 3:10.  I generally like to press the button with 1:10 left on the clock because the flashing numbers make me nervous.

Monitor B Temp - ok, this one takes some actual attention and learning on your part as the roaster operator. The challenge here is we need to keep the heat going to keep our roast developing, if we let our temp fall too much then we risk stalling out our roast.  Early experiments had us cutting the heat completely, and then watching our chamber temp drop back to 300, and our roast not making it to 2nd crack.  So, with some tinkering we’ve found that if your B temp gets to 324 cut your power back to P4 (in manual mode, or you can swap in and out of auto).  Keep checking your B temp to make sure it isn’t going up, and cut back the heat power more if necessary.  This will be especially critical during first crack, and as 2nd crack develops because the beans are releasing their own heat. (Roasters call this going exothermic, because during both crack phases the beans undergo a chemical reaction that produces heat.)  The larger your batch size, the more impact this will have on the B temp, which is why I like to dial back at 324, to give myself a buffer before hitting the safety temp trigger.