The Fresh Loaf

A Community of Amateur Bakers and Artisan Bread Enthusiasts.

Temperature profile during bake

HeiHei29er's picture
HeiHei29er

Temperature profile during bake

Was intrigued by Dan's experiments with steam.  After sending a couple DM's to him on how he captured the data, I decided to try it in my set-up.  

I don't have a Dutch Oven, but instead, I use a turkey roaster pan that's big enough for the bread loaf and a 9x5 loaf pan, which I use for steam (wet towel method).  I have a GE electric oven with upper and lower element.  I can't turn off the upper element, so I shield it with a large cookie sheet on the top rack.  The roaster is tall enough that I have to put it on the second to bottom rack position.  Because I don't like my crust super dark, I put a cookie sheet on the bottom rack to shield the bottom element too.  Finally, because the roaster pan doesn't hold much heat like a DO, I have a pizza stone that it sits on.

 

For this bake, I used probes with my Weber iGrill that I use for smoking.  One probe was attached to the rack next to the pizza stone, and the other probe was placed inside the roaster so that it wasn't touching any metal.  I was curious what the temperature did inside the roaster with the steam from the towels.  You can see the details of the bake here.  Unfortunately, I misread the dough and it was well underproofed, so I can't draw any conclusions from the oven spring, but the crust is well blistered and has nice color.

 

Preheated the oven to 470 degrees for about 1 hour.  The probe next to the stone finally got there, but inside the roaster (no steam yet), it never did get to 470 deg.  Bread was loaded and boiling water with towels was added to the 9x5 loaf pan inside the roaster.  Once back in the oven, the temp was dropped to 450 deg for 10 minutes and then 425 degrees for 10 minutes.  Remove the lid and 9x5 pan.  425 degrees for 10 minutes, 400 degrees for 10 minutes, 375 degrees for 10 minutes.  I rotate the loaf 180 degrees every time the temperature is dropped to make sure it cooks evenly.

Here's a chart of the bake.  With the steam and lid, the temperature inside the roaster plateaued at about 327 degrees.  After the lid was taken off, the temp next to the bread loaf (laying on the bottom of the roaster now) never really did come back up to the oven set point.  I think the stone helps me with getting the initial heat into loaf, but then it cools with the 327 degree pan sitting on it and the oven can't heat it back up.  However, I am getting the color I want in the bottom of the loaf, so not sure I should change it at this point.  Will have to give it some thought.

 

 

DanAyo's picture
DanAyo

Troy is the orange line the stone and blue inside the GW?

This may interest you. My nephew is a thermal engineer. He tells me that a probe can be affixed to the stone with high heat silicone. This will give us a better reading on the actual stone. Otherwise we only know the ambient temp near the stone. He told me to make sure the probe made contact with the stone when applying the silicone and that no voids existed between the probe tip and the stone. 

The actual temps of the stone will not vary that much.

Nice blisters. Wow! The insides of your GW must be loaded with steam using your method. Good Idea!

HeiHei29er's picture
HeiHei29er

Dan, Other way around.  Blue line was attached to the oven rack about 1” from the edge of the stone.  Orange line was inside GW.  Initially, the probe inside the GW was attached to the 9x5 loaf pan so the tip was suspended and measuring “air” temperature.  After 20 minutes, the pan was removed, so the probe was laying on the bottom of the GW next to the loaf.

Regarding blisters...  In addition to the pan/towels, I also misted the loaf just before going into the GW.  Not sure which contributed more.  ?

DanAyo's picture
DanAyo

Your data is quite different from mine. Maybe your temp intervals are different. Mine takes measurements every 30 seconds.

Compare my even temp lines with yours. I wouldn’t expect that much fluctuation. Wonder what is happening.

https://www.thefreshloaf.com/node/56822/cast-iron-cooker-vs-graniteware-thermal-data

HeiHei29er's picture
HeiHei29er

I think there are three main differences in our experiments.

It looks like you used convection, and I didn’t.  

You kept the oven temp more steady than me in two ways (didn’t keep dropping it and didn’t open the door to rotate loaf every 10 mins.

Your GW probe stayed in a fixed spot by going through the loaf.  Mine was suspended and then on the bottom of the pan after the lid was removed.

For the next bake, I’m going to keep convection on and see if that smoothes things out a bit.  Will probably drop to 400 deg and hold it there once I remove the lid.