though I'm fiarly new to making chocolate,, I have to agree with Brad and Sebastian and Clay.. a stone grinder can definately give you the smoothness your looking for.
i dont even use a factory modified grinder. i use a locally available brand(well not really brand, company) thats easily available to me here in India.. as far as the heat goes, all i do is give the machine a 10 minute break every 3 hours..
now to some that may not seem practical, but keep in mind that the machine cost me less than 100 US$, for me (who is working on a tight budget )it works very well..
i can generally get 48 hours of refining/conching done in 2.5 to 3 days.
-Just the opinion of a newbie who recently discovered a great passion for good chocolate :)
No need to swich of your wet grinder in intervals just remove its plastic cover and put one table fan facing electric motor , now you can run your grinder non stop.
I wanted to share how to modify the stock Ultra Grinder machine. Here are the resulting pics showing the stand, bottom ventilation and the ventilation/heating mini-tower (1,2,3). This video shows a way to drill the top ventilation holes and a reference to the Santha Air Flow Modification. Even though it was fun and educational to do it myself I feel that buying the chocolate machines from an authorized dealer provides warranty is good value.
So these machines are perfectly capable of producing fine chocolate, but with a limited yield per week depending on the conching time. I assume about 10 kgs per machine.
Brad brings up a great point in time (over 36 hours) decreasing acidity and developing flavor. I have been wondering if ventilation and temperature play an important role when conching with the Santha/Ultra machines. I recently processed a Colombian Santander (fron ChocolateAlchemy) for over 36 hours at 120-130F with a closed lid in my Ultra. The result was still acidic, which I didn't find in previous test with Ecuador cacao.
Do you think it is a good practice to open the lid and have a small fan blowing air on the chocolate?
I recently bought an Ultra Grinder. I must say after 15 or so batches most folks have no idea which chocolate was made by me in the Ultra and that bought top shelf at a retail shop. Granted we are not experts, except we know what tastes good and what doesn't , what's gritty and what isn't. This machine does a mighty fine job, and for home use.. this is economical and small in size and 10lbs is a great batch size! best wishes.