Most people only want to roast coffee once but you may be wondering if you can roast coffee twice. I wondered this too after I almost ruined a batch of beans. What I discovered is that it’s possible but I don’t recommend you make a habit of it.
Yes, you can roast coffee beans twice. It can be done but I don’t recommend it. The result will be a darker roast more quickly. The roasting process the first time has already dried out the beans. This means most of the moisture is already gone and the beans will heat up more quickly. If you choose to roast beans a second time, you’ll have to be extra careful not to burn them.
Why Would You Roast Coffee Twice?
I’ve never set out to roast coffee beans twice on purpose, but I have done it several times by necessity. Usually this is because my roaster did not complete the roast as intended.
I use a Behmor 1600 drum roaster. This drum roaster comes with a safety feature. When the roast is 75% complete, the display begins to blink. You have to press the Start button within 30 seconds to keep roasting. If you fail to press the Start button, the roaster automatically switches to cooling mode. This safety feature ensures you are watching your roast like the manufacturer recommends.
I’ve missed the blinking a few times. That causes the roaster to switch to cooling mode. Usually, my beans are done drying and may or may not have reached first crack stage. So the result is either dry beans or a very light cinnamon roast.
Since I prefer a medium or dark roast, I was faced with a dilemma. Do I roast the beans again or just throw the batch out and start over? I didn’t want to waste the beans so I roasted them again. They turned out fine but darker than usual.
What’s the Danger?
The danger with roasting beans twice is it requires even more attention to ensure you don’t burn the beans. The roasting process has already dried out the beans. In some cases, you’ve already reached first crack. The beans are going to heat up more quickly during the second roast, resulting in a much faster roast. If you’re not careful, you’ll find you’ve ruined the batch.
Another danger is attempting the second roast too soon after the first roast. Most home roasters get extremely hot. The user manual for the Behmor 1600 recommends waiting at least one hour between roasts. So if you’ve messed up your roast, you should let everything cool down completely before starting the second roast.
How Does It Affect the Taste?
The good news is there’s no discernible effect on taste. As I said before, you’ll probably end up with a darker roast than you planned. Other than that, there’s no difference.
Some home roasters are not designed to produce extremely dark roasts like Vienna or French roast. Roasting beans a second time might be a way to achieve that. Try it once and see how it goes.
Should I Roast Coffee Twice?
I view roasting twice the same way I view reheating cold coffee in the microwave. It’s not ideal. Purists wouldn’t dream of it. But faced with the choice of tossing out what you have or improvising, it’s worth it to me to improvise.
I still don’t set out to do a double roast. But at least now I know it’s possible. And to my relatively unrefined palate, there’s not a whole lot of effect, good or bad, on the taste.
Could I roast more than twice?
I’ve never tried a third roast and I wouldn’t recommend it. You’ll most likely end up with burnt, ruined beans.