Thanks for the reply that is pretty much what I was starting to put together from talking with them and one of the people that uses one for nuts down in texas. It does seem to be a very cost effective way of roasting large volumes but like you have said there seems to be quite a few variables that contribute to how good it might work for cacao. I certainly don't think I have enough experience myself to pioneer the roasting of cacao in this machine though the price to production ratio makes for a tempting option...

Ash -

I contacted Roastech and the prices of the ovens are very good. However, they really are continuous ovens and they want to be run all day long (24/7 would be better). The smallest one does up to 50kg per hour, and based on what I heard I would not try to run it for less than 6 hours at a stretch and 8-12 would probably be better for consistency ... as the roast is not entirely even with the drum has different amounts of product in it.

The temperature range is quite large and there is a VFD on the drum so you can select how long the product is in the roaster. This gives you some fine control over the roast. They also claim (but I have no way to verify), that the moisture coming out of the product is turned into steam and so does perform a sanitary kill step.

There's no one using one of them for cocoa in the US.

For small batch production I don't know that one of these makes sense. But I could easily see production situations where a 50kg machine (about US$6500) could be very useful.

That said, fine-tuning variables to get the roast you want might involve a lot of time and beans and there is no way to inspect the beans mid-roast that I know of.

:: Clay

Look forward to you sharing your experience!

That certainly brings a better understanding to the situation... All that being said it seems something like theMoffatt E32D5 might be a good way to start getting to know the use of steam...

The flavanol preservation topic is a hugely complex one. There are many, many types of flavanols, and they complex with things like sugar and proteins. Some of them taste astringent, some of them don't. Most of them degrade with heat and water - but some of them less so.

How much starting flavanols you have, how long you hold them at a given temp (and what temp you start it, how you ramp the heat), when you introduce the steam and how long you have it present, what the starting moisture is of the beans themselves - well, you get the idea. Can you get 40% less flavanol degradation? certainly, but the details are important. 40% as compared to what? Setting the beans on fire? (i exaggerate, but often comparisons are baselined against absurdly worst case scenarios to make a product look as shiningly positive as possible). it's important to know what the claim was made against.

If, say, the 40% was baselined against a medium roast non alkalizing drum roaster that doesn't employ a water injection for micro kill - the types of flavanols you'd be 'saving' would result in a more astringent flavor (actually astringency is more of a mouthfeel than a flavor) - but it would be noticeable. Additionally, steam is a wonderfully effective way of stripping off some flavors (bad and good) - so if you're working with beans that have delicate floral or fruity notes - those may disappear in the presence of steam (depends on the nature of the chemistry that causes those flavors). Moreover (but wait - there's more!) - because of the additional astringency that could result from the saving of the flavanols, flavors that weren't physically lost could be covered up by the more present flavanols now (i.e. masking effect).

People have spent decades working to understand the intricacies of this seemingly simple question 8-) Would i personally look at using one for small scale production? That depends on what end i was trying to achieve, and what my starting materials were that i had to work with. Consider a roaster as you would any other tool - it's important to select the right tool for the right job, and to select the right tool, one must have a clear understanding of what it is they want that tool to do - otherwise you could inadvertently try to use a hammer to cut a piece of wood. The right first question shouldn't be should i use a given roaster - it should be what is the right roaster to use to give xxx and yyy results with zzz materials.

Ash -

I imagine that the flavanols would fall into the category of bitter flavors.

from what I am hearing/reading roasting with super heated steam in something like the roastech r100e can achieve similar results as a medium roast in an oven but maintains a much higher level of polyphenols and supposedly up to 40% less loss of flavanols... I would look at the fat not being degraded as a good thing... I guess just wondering how a 40% less loss would effect the flavor... One might assume that that would be better and there would be more room to pull out the flavor you are looking for... Really don't know just trying to learn more...

Well, i suppose that depends on what your definition of "better" is 8-) If you want a dark roast flavor profile, this is not the road you should take. If you want a lighter roast, it has it's merits - is it better? Well, especially when it comes to flavor - that's for you to decide!

Same for health - what do you mean by nutritional profile? Fat is part of the nutritional profile - this will do nothing to degrade fat. If you mean flavanols - well, generally speaking, water and heat are the enemy of flavanols.

The more precise you can be in your definition of what 'better' means, the more informed response we'll be able to provide.

On the bit of a larger scale... anybody have any experience with something like roastecksR100E?

[ Editor's Note: That's the Roastech R100E. ]

Also, if you can find it, Moffat makes (or used to) cookie racks for their ovens that allow 8 full sized sheet pans. Or you can just add some simple brackets to achieve the same thing. I did it for mine and the temp distribution throughout is pretty uniform.

This is a very small (consumer) version of what is often referred to as a "combi" oven and that is often found in commercial kitchens. What makes the Sharp a little different from most combis is that it also includes a microwave cooking option, something that is not found in most commercial combis.

You can achieve an improved level of microbial kill by using a combi oven with steam for a portion of the roasting cycle. You can get the oven quite hot, add the beans on trays, start the steam, and roast for a relatively short time. At which point you can remove the beans to let them cool and turn the oven down to a much lower temperature for the remainder of the roasting cycle. This way you can effectively achieve a lower roast profile while getting the benefit of the microbial kill step.

One thing to consider is that once the beans are cooled you could crack and winnow them before putting the nib back in the roaster. This could mean much shorter roast times as well as more even roasts.

If you want a larger oven, something like a Moffatt E32D5 will give you the steam option with a five full-size sheet pan capacity.

Pretty well micro scale but...

What about something like the little steam ovens from sharp sharp ax-1200?

I suppose my next question would be then using steam can you achieve a better flavor and maintain more of the nutrition as it says in a few of the reports I have been recently reading? as you have said on the light and medium profile anyways? Almost all of the roasted chocolate I try pretty much taste burnt to me... I would hope to get a medium roast without the burnt chocolate flavor coming through while maintaining as much nutritional value as possible... I notice a big difference in the way raw cacao makes me feel but do understand the need for heat in the chocolate making process... There for I would hope to compromise with a method that maintains the highest values of nutrition and flavor...

I wouldn't say it's new - i'd used them for many years, but not on a small scale. Excellent way to achieve an effective micro kill and get a low to medium roast profile. Anytime your'e working with superheated steam and pressures on a small scale, your costs are going to be 3x higher than if you were simply due to the safety elements necessary to prevent your roaster from turning into a bomb.

Hi there, anybody have experience with the new method of superheated steam roasting? Or the roasters them selves and wether or not it would be practical to acquire a roaster for small scale production... I have read that it is a way to maintain maximum nutrition and health benefit...