I want to try roasting my own cocoa beans at home. I stumbled across a 1947 'Home Ec' booklet put out by General Foods (now Kraft) that gave a brief history of cocoa making in the US and talks about the fact that Baker's Chocolate for baking is just roasted and shelled cocoa beans ground up.
I understand that there is quite an art to making chocolate. I have looked at options for roasting cocoa beans and I wonder of a coffee roaster could be modified to do the job right.
I have been researching vanilla for awhile and I am a friend of 'The Vanilla Queen', Patricia Rain. I have also imported some vanilla beans from the only commercial vanilla bean farmer in Australia. They are lovely.
I am in serch of the best and freshest products to use in my own cooking and I hope to promote such to others.
I, too, am looking into how I can buy fermented, but not yet roasted cocoa beans of good quality in bulk amounts at favorable prices.
You can roast in your oven, you don't need a coffee roaster, if you have one that will work. The temperatures are lower for roasting cocoa so that's the only place modification may be necessary. You can find lots of info at ChocolateAlchemy.com. I have found that the best way to roast in the oven is to use a baking stone in the oven, preheat for at least 30 minutes @200 c. Then spread the beans in a single layer on a sheet pan-perforated is better (I now use those wire pizza racks/trays). Roasting temperatures and time vary according to bean size and type, desired flavor, and ovens.
Before I bought any chocolate making machinery, I would roast and winnow my beans, and then grind them in a coffee grinder with sugar and sometimes vanilla. It was crude chocolate texturally, but delicious nonetheless.
As for beans, Clay has many quality varieties on this site, and so does John Nanci at chocolatealchemy.
Enjoy, it's a fun path to journey.
I offer a variety of beans in 10 pound quantities at quite reasonable prices. I chose this weight because it fits in a USPS Priority Mail flat rate box and because it's a good size to start experimenting with. When you get to the point where you want more beans - no problem. We can offer the same beans listed here in bag quantities (about 100 pounds) and I am working with a ChocolateLife member to secure several tonnes of beans, so we can meet your needs as you grow. We are offering mostly specialty beans with some "value" beans from West Africa and the Dominican Republic.
I let Pam Williams know that she can refer to me as a source for beans for her students. Maybe you can check with her about that, too.
While it is possible to modify a home coffee roaster in general those machines get too hot and spin too fast. So if you're serious about repeatable results a device like the Behmor - at a minimum - is a must. When your demand grows you can get a professional coffee roaster. They cost a lot more but you can roast a lot more at the same time, too and you will get far more consistent results.
There is another thing to consider ... which is where your interest truly lies. Do you want to make chocolate or tinker with machinery? If you want to tinker with machinery then by all means, go ahead. But if you don't and/or aren't mechanically inclined, then don't. Focus on what you want to do and look for ways to accomplish what you want using machines that other people make. The HomeBrew group is the real place to have this discussion and there is already at least one forum thread on equipment.
Until then, roasting in the oven works well as Holycacao says and his advice is good. For consistency it make sense to put some sort of ceramic object in the oven. There are liners that you can use, bricks, or the pizza stone. The requirement is to stabilize the temperature of the oven and minimize temperature changes when you open and close the door. Having a lot of ceramic reduces temperature "bounce" to a minimum. I would also recommend not depending on the thermometer in the oven. Buy a separate one with a large dial that you can keep in the oven.
Finally, something that Alan McClure of Patric Chocolate said in a talk he gave in New York last year really rung true to me: become an obsessive note taker. Keep track of as many variables as you can think of - including humidity - so that from batch to batch you learn to identify aspects of the environment that affect the chocolate you're making.