The Fresh Loaf

A Community of Amateur Bakers and Artisan Bread Enthusiasts.

Gas fired Masonry or Mud oven - retained heat?

Gadjowheaty's picture
Gadjowheaty

Gas fired Masonry or Mud oven - retained heat?

This may be completely ludicrous, just playing scenarios.  It mostly applies to commercial needs as on a small home scale, I know, wood isn't as prohibitive.

The availability of wood is not constant - some places access is easier or less expensive than others.  Additionally, though I hate to use it, it's arguable anymore which harms the environment and resources more - the use of wood to burn, or using some sort of a "flame engine," don't know what you call it, but something that fires from a nozzle live flame in huge amounts (technical description; awesome, I know), used not to direct fire a bake but to do the same thing wood firing does, heat the masonry or mud to get to the proper retained heat for bakes.

Some sort of jet firing apparatus to heat the oven surfaces, not to direct fire the chamber itself during a bake.  Is there such a thing done?  Is it a viable (efficient, cost-beneficial) as a small commercial bakery brick oven alternative?

idaveindy's picture
idaveindy

http://texasovenco.com/propane-wand/

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This post: https://www.thefreshloaf.com/node/36357/persianiranian-barbari-bread

has photos of a gas wand (unsure if natural gas or propane) used to heat a brick bread oven.

Scroll down into the comments and there are videos of the barbari process. I forget which ones, but at least one of the videos shows the wand being used to heat the oven.

Gadjowheaty's picture
Gadjowheaty

I'm absolutely stunned.  All else aside, that thread is one of the most extraordinary studies in culinary anthropology I've ever read.  Thanks for pointing me to it, Dave.  

More than a few lives back, I was an L.A. actor.  My very first waiting gig was for an Iranian restaurant and from what I can tell, now, it was Barbari that they had, that brought me to gobble it down like a crazy person. 

Thanks for the info on the wand too.  Perfect. Knew I'd seen them in other uses but didn't know what they were called.

One of the posts, I believe, he was told by the oven manufacturer to be very cautious with using a wand (I noticed his is from HD, at 500K btus), fearing the oven couldn't handle it.  The OP indicated 2 years and counting at the time, without issue.  Do you have any thoughts on this?  Is the wand pretty hard on the surfaces (would it be cycling that is the issue?)?

idaveindy's picture
idaveindy

I have no direct experience with gas wands or brick/cob/mud ovens, so I can't say.

My brief engineering background and some life experience informs me that thermal expansion and contraction is a thing to be concerned about. Slow thermal change is better than rapid thermal change, but the total delta must still be allowed for regardless of the speed from one extreme to the other.

If I remember correctly, there is some advice in regards to thermal expansion/contraction in "The Bread Builders", both in regards to construction as well as in regards to operation.

Gadjowheaty's picture
Gadjowheaty

OK thanks, I'll re-read the book and dig further.  Wasn't aware delta is also a consideration with these materials - thought it was cycling speed, really, only.  Good to know.

Much appreciated Dave.

 

Paul

yozzause's picture
yozzause

i found that university of you tube has some great Venturi gas burner projects well worth a look at

Gadjowheaty's picture
Gadjowheaty

LOL, University of You Tube.  Is that something like "Google MD," the place where we find out just enough to drive our doc's nuts when we visit?

yozzause's picture
yozzause

Its quite good watching and learning and then giving it a go. Reminds me of the bloke that bought a house in a council estate where all the houses are identical. He says to the neighbour "i see you have wallpapered your Lounge, do you mind me asking how many rolls you bought" and he says  12 rolls . Anyway a week later the guy says to the  neighbour ive just finished wallpapering my lounge and i have 4 rolls left over and the neighbour says so did I!

Gadjowheaty's picture
Gadjowheaty

😁