How to achieve desired flavours during roasting?

Hi :slight_smile: I’m new to coffee roasting.

Theoretically, I know Maillard’s Reaction happens from approximately 120 degrees celsius to 150 degrees celsius and Maillard’s reaction yields savoury, floral, chocolaty, earthy, and roasted flavours.

Likewise, Caramelisation starts at approximately 170 degrees celsius and yields fruity, caramelly, and nutty aromas.

But practically how to use this information? Should I reduce the heat and stretch out the time taken during the Maillard reaction to develop more Maillard reaction flavour characteristics? My question might sound silly but I’m confused about how to apply this theory while roasting in real life. Please help.

PS: I have learned this theory from Scott Rao’s roaster companion book as well as watching Youtube Videos.

Thanks a lot in advance!

One approach is to do a lot of proper experimentation - roast in as controlled an environment as you can achieve, modify one aspect of your roast at a time, and get really good at cupping and documenting your observations (disclaimer: this is not my approach as I’m horribly indisciplined; I just try to get a Rao-ish curve and enjoy what comes out the chute).

If this sounds like something you want to pursue, then Rob Hoos’ Modulating the Flavor Profile of Coffee might be the next add to your library. It’s an interesting read even if you don’t have scientific aims.

+1 @sgtbakerrahulne ‘s advice. Hoos’ book gives ideas about how to change the roast profile to enhance particular flavors.

I’d also recommend using Overlay with a prior roast (of the same bean if possible). This makes it easy to fine tune and experiment. You don’t need big changes, just modify the power intervals by only a minute or so, or add/subtract 15-30 seconds to the end of the roast, and see how you like the resulting flavors in the cup. Buy beans in large enough quantities to give yourself several iterations to home in on a great profile.


Great point! I almost always overlay my best previous roast if it’s a repeat roast of a particular bean. It’s really helpful in guiding how I back off power between drying and 1C so that I get a smooth gentle ROR decay. Usually the first roast is guesswork and good but not great, but after that it’s easy to see how the power profile needs to be tweaked.