Hi all,

First post here, hope it's not too much of a newbie question.

I've been home roasting for a few months, using the KISS method (deep cast iron skillet on electric burner).

I pre-heat for 10 minutes and roast 1 cup of beans and stir constantly until complete.

After trying several different types, I've been using the Colombian Supremo lately (last 12 roasts have been this bean).

First crack starts around 8:20 and is complete by 10:30, The first pop of second crack hits around the 12:00 mark and I immediately dump into a cool metal pan.

I had great results all winter, I'd run outside in 0-15F temperature and pour beans back and forth between 2 containers. The resulting coffee was absolutely excellent (drip, Aeropress and Breville Espresso machine).

I got tired of running outside and freezing my butt off, so I put together a shop-vac/bucket/colander cooling unit.

I've done 2 roasts with the new cooling unit and am amazed at how fast it cools the beans (30 seconds or less to room temp), I was really pleased, until I tasted the coffee!

I used the 'quick cooled' coffee after 24 hour rest and have used it every day for the last 5 days with very little taste improvement since the 48 hour point.

The beans and the ground coffee smells 'sour' with just a slight 'coffee' smell.

I did a few searches and found very little about cooling things too fast. Maybe I need to roast a little longer before I cool them?

Any advice or thought would be greatly appreciated.

From a color perspective, the beans appear to be between City and Full City roast.

Thanks,
AJ

I would try roasting longer before cooling, as your now stopping the roast sooner after pulling the beans.

Thanks,
I will try that.

Can a minute at the end of the roast make THAT big of a difference?

It's amazing to me that I've been so lucky with my roasts, the difference between these roasts is like 'flat stale warm cheap beer" vs really good cold draft beer.

I'll be doing a roast tomorrow (while I'm warming up after tapping maple trees!)

Is there anything else that can mess up a roast that bad?

Thanks,
AJ

Can you detail your original cooling method a bit more? And if possible go back to your old method and make sure that's where the difference is. Please share your results. I believe there's something to your original cooling method. Also, what was the aroma like with your original cooling method?

My original method was to dump the beans into a tin loaf pan that was sitting at room temp (approx 65F). Then I covered the loaf pan with a piece of aluminum foil, so I wouldn't share the 'aroma' (aka smoke) all the way from the basement up the stairs, through the house and out the back. I'd then slowly dump the beans from the metal loaf pan into a hard plastic colander, then back to the pan etc. The outside temperature was in the 20s at the warmest. Typically it has been in the teens with the wind blowing.

When I roast in the basement, I have a vent over the pan to send the smoke outside. I'd imagine the beans stayed together in the loaf pan for a minute or so before I started cooling them. I probably dumped them back and forth for 2 minutes and at that point they were probably around 80F.

One additional difference I just thought about is that using the original method, I'd just leave the loaf pan in the garage (probably 30F), for a few hours before I put them in a loosely capped mason jar. In the new method, i took them directly from the cooler into the mason jar.

Hope this additional info help, because I'm having withdrawals from my great coffee!

The aroma with the original method was a medium pleasant aroma after cooling but a very nice strong 'coffee' aroma when ground.

I also always taste a bean after each roast. The beans from the original method where great to just eat! The beans that were only cooled to room temp with the shop-vac didn't have that coffee 'pop' (sorry I can't really describe taste and smell very well).

Thanks,
AJ

I have not advanced my cooling
Method beyond run around in the cold and pi*#^%#g my wife off by making a bunch of dirty pots yet...

The first things i would want to rule out are: oils left behind in your pan. After several roasts last December i started struggling woth terrible awful roasts. Then i realized i was leaving
Behind a residue of oil that was not coming off woth regular dawn soap. After fully cleaning this was fixed. I imagine that cast iron might be even more problematic, but maybe would take longer to hit than in stainless.

Second: the chaff. My face is usually covered in chaff after tossing and blowing. Maybe the suction is not removing as much of the chaff as before. Compounding the problem would be that in a skillet with no airflow chaff will def be burned and taste terrible. In addition, it is obviously more absorbent than the
Bean and so might be both burned and absorbing rancid oils. Or not...

Just some thoughts fwiw

AJ,

If I am understanding your procedures correctly, your previous "good" roasts probably took an extra few minutes to cool, and during much of that period, the hot beans were kept hot inside an enclosed container while you walked up stairs and outside to begin tossing them about. During that time, I'd say the beans continued to develop to a darker roast level while you were going upstairs and outside.

Your new method, again...if I understand correctly, you are cooling immediately in the same location where you are roasting your beans, so there is no additional development inside a closed container. Also, the new cooling method is extremely fast with air being forced though the beans. This will halt the roast development much more quickly. So, if you stopped both roasts at the same level of development, you new roast should be a lot lighter. It could well be underdeveloped compared to your previous roasts.

I'd try your old method again, at least once, and if your roasts return to their former tastes, I think you have your answer.

If not, I certainly would look to the cleanliness of your roasting implements to make sure you don't have rancid oils contaminating your roast, as mentioned by others. I'll be curious to hear what you learn.

Since your roast method is with a skillet, it will always produce a more uneven result than a drum or air roaster from my experience. This isn't as much of a problem at a darker roast level, but if you try to stop a roast at too light of a level, you can have some beans that haven't yet hit first crack likely. So your faster cooling method is likely a result of this effect as just a guess.

I've had some good results come from a skillet, but they are fairly unpredictable for me. In some ways, they are like a melange blend, but just all in one roast rather than roasting a few different levels the same bean and blending.

I finally got around to doing another roast, Here is a picture right after cooling.



I tasted a couple beans and taste that great coffee flavor.

I'll brew a cup with it in the morning and see if it's good to go.

I think you all hit the nail on the head, that I stopped the roast too soon and it was 'coasting' in between the roaster and outside cooling.

So after I roasted it (a little longer than normal), I dumped it into the loaf pan and left it there for one minute before dropping it into the rapid cooler.

I actually went a bit darker than I normally do and ended up with a few of the 'really dark' beans, which I normally don't

We will see!

Thanks all,
AJ

I also stovetop roast and feel that you may need to improve overall agitation of beans and using a lower temp. It is pretty clear the beans did not roll but "scooted" if you will, resulting in burned flat bottoms. In my experience that will produce a very distinctive ashy flavor, most predominate in the aftertaste, even if everything else is right. This can be improved by lowering the stovetop temp and increasing agitation as i said above.

As to the loaf, it might be better to lower the post first crack stove temp and carry out that time on the stove, perhaps only a few seconds, and then try the quick cool?