Cooling

[jamescary]

Hi!
New here and trying to wrap my head around the roast process.

I was reading in the coffee roasting threads that a lot of coffee roasters will try to rapidly cool their beans when they've reached a finished roast.

I was wondering is there anyone doing this with chocolate?

[josh]

Jim,

Good question and often overlooked because of the low volume of cacao roasted by "alchemists." It is VERY important and you can apply the exact same principles as coffee roasting.

Here in Guatemala, we roast our coffee and cacao in the same machines more or less for local consumption. The only difference is that that cacao only cracks once typically when roasting, while coffee can be "cracked" twice or so. That is, it makes the popping sound as the fat or water content explodes in the heat.

You you need to cool it quickly and evenly and if you are using a large machine make sure the vents are clean in the cooling rack.

One important note for everyones else, quit killing your beans, try no more than 375-400C for 6-12 min. and induct air or stick with a drum type roller i.e. the Belmor that John sells or pony up for a 5K coffee roaster. The oven will not allow you to control roasting well due to changes in type and humidity per batch.

Jungle OUT

[jamescary]

Thanks Josh!

I plan on using my winnowing device (a device yet to be built and tested, but will provide lots of cool air) to cool the beans first, then I plan to crack and winnow the beans.

Also, as part of the pre-roast, is washing the beans a good idea? I noticed some of the beans have extra sediment on them which may lend some of their undesired flavorings to the batch.

Also, I did some tests with my oven using a standard oven thermometer and noticed that the temperature swings quite a bit (+/- 30F). So, I will probably be using a different roasting technique. What type of roaster are you using?

[josh]

James,

More great questions. First, generally you do not want to wash the beans-rookie mistake. This will rinse away the sugar inside and leave you with a tasteless bean only good for making butter. Stuff on the outside is fine unless it's concrete or burlap or plastic. This "stuff" is usually the dried fruit or pod which poses no problem. I have even tried roasting coffee with the cacao to add flavor but nothing sticks, it only adds humidity, which can be useful is someone ships you some year old plus beans. So, in short, nothing on the outside poses a problem.

Also, oven roasting can work just start at 425 and account for the door being open while you push the beans inside??? All roasters will change temps and you just have to dial in what you are working with. What I don't like about an oven roaster is lack of air circulation and the fact that it cooks only the outside whereas you are looking for a more even roast, i.e. the inside of the bean too not just the outside. Too much heat and you will cook of the "good" fat and taste while leaving you with a brittle dry and tasteless bean. Good luck and keep plugging away, thats the only way to learn in my opinion.

Oh, I have a bunch of roasters. If I could have my perfect roaster, it would be a forced electric (heated) air unit, spinning drum type with a vented rotating cooling bed beneath, run by the Brazilian Womans Tanning and Bikini Swimsuit Federation. In the interim, I will continue to work with gas and electric knock-off Probat/Dietrich type drum roasters run by smelly expats and construction workers. Gods Speed Man.

Jungle

[jamescary]

Thanks for the tip! I'll roast it all.

I was reading some of the Science of Chocolate yesterday and noticed that it pretty much said the same thing as you about roasting: heat the bean on the inside. There was also a diagram showing how different bean size can be problematic for doing this.

Which made me wonder would pre-sorting the beans be worth it? I think a good tool here would be needed -- I'm not going to sort the beans one by one -- maybe the Bikini Swimsuit Federation would like to help here? ;)

[Alchemist]

josh said:

Jim,
One important note for everyones else, quit killing your beans, try no more than 375-400C for 6-12 min. and induct air or stick with a drum type roller i.e. the Belmor that John sells or pony up for a 5K coffee roaster. The oven will not allow you to control roasting well due to changes in type and humidity per batch.

Jungle OUT

Josh, I think you may be mistaken how people are roasting. 375-400 C is going to kill beans as you put it. Do you mean F? And something people should try and wrap their heads around is that ambient temperature is not bean temperature.

I know I have talked about roasting in a bbq with a drum at 500-600 F. The "trick" to this is that lots (4 lbs) of beans were being roasted, the heat had to get through a pretty fine mesh and there was lots of heat loss off the bbq. Even when roasting like that, what the beans saw were probably around 350 F, and I stopped the roast when that pop you mentioned occurred, which tells you the beans are around 300 F. Basically the same as you are doing.

Now I roast most often in a roaster I built. It has much better convection, a larger mesh and correspondingly the ambient is rarely over 300, and often 270 F.

As for cooling, if they are popping, yes, I like to get them cool, but I have to say I have not noticed a huge impact from a slow cooling. My roast this morning even I got the beans under 200 F and just turn off the roaster. I have found cooling to be less critical than coffee. YMMV.

[seneca]

I'd agree with John both that cooling is a LOT less important with cacao than with coffee, and that the temperatures discussed above seem way too high.

Naturally, roasting (like any other component of this process) is dependent on taste, but in my experience if you're working with really unique and flavorful cacao, slow roasts not exceeding 300F will work best to accentuate the more delicate and rare flavors in your chocolate. For what it's worth, in a lot of my roasts recently I've been shooting for ambient (bean surface) temperatures in the 275-295F range...

[jamescary]

Thanks, I understand that it's not technically temperature that we're shooting for but a heat transfer. So all these variables come into play (size of roast, type of bean, temperature, time of roast, etc).