Help, I've moved my roaster and things are not the same!

[Wendy]

Hi, I really need some help.
I have been roasting commercially for the last 5 years on a Toper 5kg and all has been well until I recently moved my roaster to my garage. I have been getting really uneven roasts with Sumatran and Guatemalan. At first I thought maybe my roaster wasn't level, but it is then I thought the gas is too cold outside, so I moved it, no different. Then we checked the temp probes and yes they were out of whack but now they are sorted I am still having the same problems. It is really cold here at the moment, so I am thinking bean temp/moisture is the problem. I dropped the temp I charge the beans at, no better. I have played round with airflow, but no better. I am pulling my hair out. Any help would be appreciated. I am also roasting Colombian and seem to be ok with that. I have some beans that are completely under roasted and a few that are too roasted but about 80% ok. I don't know what to do! I sold my cafe to concentrate on roasting only, but I am losing my confidence to get out there and sell my product with this going on.
Thanks

 

[John P]

The bean structure of Sumatran and Guatemalan are quite different, so I wouldn't see those as a specific factor. What about age of those beans vs your Colombian? How were the beans stored? It very well could be a moisture difference.

I would think it's environmental conditions or airflow, but you seem to have checked those. I am sure your garage is not the same temp, etc. as your former spot. Either adjust the environment to match, or adjust the roaster to compensate.

Is your drum rotation speed the same, is anything out of whack there?

And you said the temp probes were out of whack. Was this definitely after you moved the roaster, or have they been out of whack and you unknowingly adjusted your roasting to compensate. How did they get out of whack? What else could have been moved, damaged, altered ?

 

[Wendy]

Hi John
thanks for the reply, someone else mentioned drum rotation to me. The engineer I have said it was impossible to change, but do you know what it should be ? I have received a new sack of green yesterday and you guessed it no change. The only thing I can say is the flue is slightly shorter than before and there is a different hat on it. The problem got worse a few weeks after moving so we started looking at factors why, (it has got stedily colder since moving) and one of the things that came up was that I had an incorrect drum temp dial on the front of the roaster so we calibrated it but yes it has been out of whack for ages. I have started leaving a heater on in the garage for an hour or so to warm up the building but it hasn't helped. There is one other thing, if I leave the gate open after roasting I can still hear a few few beans rolling around and up to 5mins later they fly out and they are usually really blonde. Its as though a few beans are getting stuck somewhere. Thanks

 

[Wendy]

Sorry I didn't answer your question, the Colombian is the same age as the others.

 

[wmark]

How about ambient temperature(s). How did they change ? Are they consistent ?

 

[John P]

If your roaster will have a permanent home in your garage, you need to cough up the coin and have the garage heated and temperature controlled just like any shop environment would be. Space heaters or the like are not a suitable solution. When you move your roaster to a spot with unstable temps you should expect to have unstable results.

It seems like some of the settings were off on your roaster. Stabilize everything - including the environmental temp -- check all of your probes for accuracy, and re-formulate your roasting profiles and begin anew.

 

[Wendy]

Thanks for the reply, I think you may be right, insulation might be an option. The cafe used to be really hot all the time but the beans have always been stored in my garage so no change there. I have spent some time talking to someone at Toper and I have been getting better results with airflow control much more even overall but still say 20 beans per 5kg roast that are totally under. I'm not sure if i mentioned it but I usually have a few beans still rattling round in the roaster after I have dumped all the beans. When they eventually fly out sometimes up to 4 mins later they are usually very under roasted not charcol as you might suspect. Which makes me think a few beans are getting stuck somewhere.

 

[wmark]

The bean chute.

I would suspect that all is not as it was after the move. Heck! I have to make roasting adjustments after cleaning out the machine.