Hi Brian,

near to 100% humidity here, the rain season is up to july with a little sunchine in march. There is no supplier here of that sort of plastic so will try with the "plexiglass".

Hi angenieux, I don't know your weather conditions, but I slow air/sun dry my beans naturally on elevated mesh beds under a transparent plastic roof (here is a link to the plastic sheets I use - I don't use their design I have my own dryer design, I just use their plastic http://www.tecnatrop.com/secafen/secafen-ww.htm )and even when we have a solid week of no sun they dry fine. the key for us is to make sure air is moving both above and below the beans 24 hours a day. Even when its very wet and humid they will dry through transpiration, although when there isn't any sun at all for 7 days they don't look as good. But the flavor is fine.

Saludos, brian

volker lehman has the slickest air dryer I've seen at his flor de cacao installation in Palos Blancos (alto Beni) bolivia. uses wood for heat (which costs basically nothing where he is) but no smoke flavor, the heat is transfered through a coupler using fire heated water. But it didn't look cheap, he had some donor $$ I believe . But design-wise, it was impeccable.

We had a very thorough talk about focal distances to ensure my house didn't burn down 8-) she made sure to design it such that the focal point of the lens was 2" 'below' the bottom - that way it was still a pretty significant concentration of heat, but not enough to get anywhere near me needing to use my fire insurance!

Sebastian -

I've thought of several ways to transfer heat to a thermal mass inexpensively and then use that heat to reduce drying time but using Fresnels never occurred to me. It's a very good idea.

One reason I did not think seriously consider Fresnel lenses is that they can concentrate solar energy and can get hot enough to set wood on fire at the point of focus on a bright day. Can I assume your daughter is not focusing on the beans or the surface of the drying pad? Out of focus? Using the energy to heat some thermal mass and then that heat is transferred over the beans (using air)?

:: Clay

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@DiscoverChoc

my daughter actually just did her science project on improved solar dryers, incorporating inexpensive fresnel lens' as a way to inexpensively increase throughput. she saw a 42.8% increase in throughput as a result. she's writing it up now, but might be something to consider.

Gordon,

Thank you for your propositions

I have a project to construct a dryer with plexiglas (don't know the term exact in english, a kind of transparent solid plastic), walls and roof in the same material with a passage of air one end to the other.Sure that i prefer to use less energy but before i can construct the dryer i was researching a solution meanwhile to keep the quality of the beans.

Angenieux -

I wonder if there is a way to construct an inexpensive dryer. This would probably use less energy than freezing the beans, especially if you have many sacks of them.

http://www.grainpro.com/?page=grainpro-collapsible-dryer-case2
http://www.grainpro.com/?page=grainpro-solar-bubble-dryer

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@DiscoverChoc

Sounds like an expensive proposition if you're doing in bulk. Much more so than air conditioning. I've frozen them in liquid nitrogen, and they were fine. as long as you can keep the freezer from minimal defrost cycles and manage the condensation upon thawing, you should be fine.

hello,

I am back to say that my last try of tempering my cacao liquor was the best (according to the people who taste it here), the bars were shinning, "croquant" and a so nice cacao flavor "en bouche"...even in a place with no air conditionner, always "au bain marie".

As the season of the cacao is started here, i am planning to harvest soon. The problem is that the rain season is also here and it is a real challenge to dry the pods in this humidity. A friend of mine adviced me to freeze the cacao seeds after fermentation??? To dry them after when there is a little sun

Does anyone has ever experienced that?

updated by @angenieux-drupa: 04/12/15 22:45:18