Day: November 17, 2015

Tuesday, 17 November 2015

09:39 – I did some testing yesterday and overnight for the section in the book on Thermos cooking. I used two containers, a 2-liter Thermos bottle and, just for fun, the insulated carafe from our Braun coffee maker.

I brought a large pot of water to a boil and filled each of the containers to preheat it. After five minutes, I emptied the preheat water back into the pot, brought it to a full boil again, refilled the containers, recorded their initial temperatures, and capped them. Both were initially at 99.3 ºC. After 2 hours, the Thermos bottle was still at 99.1 ºC and the carafe had fallen to 76.5 ºC. After 3.5 hours, the Thermos bottle was at 95.0 ºC and the carafe had fallen all the way to 58.2 ºC. I dumped the water in the carafe at that point, because it had cooled so far that it wouldn’t be useful for cooking. After 8 hours, the Thermos bottle was down to 90.4 ºC, and I went to bed. This morning, I checked the temperature in the Thermos. After 18 hours, it was at 76.3 ºC, so I dumped the water into the sink.

The Thermos bottle turned out to be fine for Thermos cooking. Maintaining 99 ºC for two hours is essentially the same as boiling something for two hours, and even 95 ºC is close enough to boiling to count as simmering.

I did a lot of Thermos cooking back in the 70’s, in college and after, and I learned there are two tricks. First, ALWAYS preheat the Thermos bottle with boiling water. Second, don’t just dump the dry food into the Thermos and cover it with boiling water. A pound or so of room temperature rice, pasta, or beans takes a lot of heat to get up to boiling temperature, and takes that heat out of the water you just added. Instead, combine the food and water in the pot, bring it to a good boil, and THEN transfer it to the preheated Thermos bottle. You end up with the equivalent of a low-tech, non-powered slow cooker. Oh, yeah, the third thing I learned. If you’re adding meat to the Thermos bottle, brown it first in a little oil, add the water, bring it to a boil, and let it boil in the pot for a few minutes before you transfer it to the Thermos bottle. It’s also useful to have a second pot to hold the boiling water while you transfer the wet, hot food into the Thermos. Then fill the Thermos with the boiling water. Otherwise, you may find you’ve filled the Thermos with mostly water and have lots of food left in the pot with no room left in the Thermos.

Read the comments: 26 Comments
// ------------------------------------------------------------------------------- // end of file archive.php // -------------------------------------------------------------------------------