Roasting with a live flame inside the drum?

[Stuggi]

I just saw this vid on the tube;



and I'm a bit preplexed about the way they roast their coffee.

Is there anyone in here who has any experience with this sort of setup, and how good it is?

I'm kinda thinking of building my own model...

[another_jim]

It could be that the flames were overlaid in editing. They don't look right; and I've never seen a roaster that does this under normal circumstances. Beans do catch fire occasionally in drum roasters, but it's a pretty bad accident that shuts down the plant until the roaster is stripped and cleaned, and the stacks are all scrubbed out.

[Stuggi]

Well, the really wierd thing is the redish tint of the flame. The only flame I know that produces that kind of flame is hydrogen, and that would be really wierd.

BTW, what would anybody gain from overlaying flames?

[another_jim]

It's an unregistered video. Perhaps somebody may have bought the beans, thought they were ashy, and decided to do some appropriate editing on the promo video.

[boar_d_laze]

Optical delusion.

There's a live fire somewhere in the roaster either to heat the drum or supply radiant energy to a screen drum. Considering it's a commercial roaster, probably to heat the drum. In any case, the fire is not actually inside the drum itself. While there are a number of circumstances under which it might appear so, it's likely either (a) the roaster's sight lens was not entirely clean and the camera angle was not entirely straight on. The camera picked up a reflection of the flame which flared slightly on the interior surface. The interior surface acted something like a "one-way mirror," which moved the flame's apparent location to the interior of the drum. Another possibility is that (b) the glass was not an optical flat and refracted the camera's view in the same way peering through water creates refraction.

One of the biggest clues that this is an unintentional artifact is the way the flames' depth and location apparently move with the camera. Indeed, when the roast master took a sample, the camera moved in, and for a moment it is clear the flames are outside the drum, off to the side(s) Watch for them on the frame-right side of the drum.

Hope this helps,
Rich

[Stuggi]

Well, doesn't look that way to me, but hey who knows?

What keeps me wondering is that the roastmaster refers to a live gasflame INSIDE the drum. Kinda hard to get that wrong?

I'm going to pop them an email and see what they say.

[Greenman]

Greetings

Listening to the guy he says there is a live flame in the drum and you can see him insert a gas wand with flame to light up the gas?
When I was a kid there was a shop with a roaster in the window that had a flame bar in the centre of the drum so the beans tumbled through the flame.
That smell while we stood waiting for the bus was so distinct I can remember it like yesterday.

Andy

[boar_d_laze]

If I'm wrong, I'm wrong.

Rich

[Stuggi]

This's becoming interesting. I've sent them an email, so hopefully they'll reply soon.

If this works out as being a possible roasting method, I'll just have to build one. (Or accually, I'm allready building one, I have the propane burner manifold complete, I'm now working on the air/gas mixer (turns out, one has to mix the gas with air BEFORE blowing it into the burner manifold, otherwise one'll get long carbonizing yellow flames :/ )

[cannonfodder]

Sounds like an acetylene flame before you mix in the oxygen. Little carbon bunnies all over everything, what a mess. That would probably have an adverse effect on the coffee.

[Paul_Pratt]

It looks like a vintage roaster. In CFTS by Bersten he mentions 2 english made roasters witha direct flame inside the drum.

paul

[rasqual]

From the roaster:

I use a pre WW2 coffee roaster built by a British company called Whitmee.the flame is contained inside the roasting drum and therefore the heat is totally radiant , there is no conductive or convective heat used in the process. This is real seat of the pants roasting and requires experience and of course the 'Black Art'

Googling Whitmee yields interesting hits -- not all on the first page of results.

[Stuggi]

Yupp, I got the same response today.

[boar_d_laze]

Ahhh. And aha!

Rich

[another_jim]

I got to try me some of this coffee.

Pre-WWII tech British coffee? Can you say "and now for something completely different?" I knew you could.

[Stuggi]

http://www.pumphreys-coffee.co.uk/

[cannonfodder]

Hmm, I thought I might see if they ship to the states but it looks like the only espresso blend they have that is not charred is the Daterra Bruzzi.

[jason_casale]

If the roaster is built right the flame can be directly inside the drum.
Mine is a perforated drum with holes in it about 1 inch thick stainless steel with a ribbon burner that flames go inside the drum in the roasting process. This can work as long as the drum rotates at the right speed to keep the coffee from scorching. This a is a proven way to roast coffee old school. My roaster roast manually with a gas adjustment from high to low and has one analog gauge on it. The rest is up to you. works great.

[farmroast]

If the roaster is built right the flame can be directly inside the drum.
Mine is a perforated drum with holes in it about 1 inch thick stainless steel with a ribbon burner that flames go inside the drum in the roasting process. This can work as long as the drum rotates at the right speed to keep the coffee from scorching. This a is a proven way to roast coffee old school. My roaster roast manually with a gas adjustment from high to low and has one analog gauge on it. The rest is up to you. works great.

Any pics of your roaster? Ed

[jason_casale]

My Roaster Pictures are on my blog for those who wanted to see them.