Thermal Cooking FAQ
- the inner pot needs to be at least 80% full of food or water. Air is a poor conductor of heat so a pot filled with air instead of food will likely not have enough thermal mass to retain the heat to cook the food
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November 4, 2008 at 12:12 am
Hi there,
Can the inner pot be used on an induction cooker to heat up ??
November 4, 2008 at 9:04 am
Not all thermal cookers are made the same. Of the four different branded commercial thermal cookers I have only the Thermos brand passed the induction test where a magnet was able to stick and hold to the bottom of the inner pot.
The clad bottom on the Thermos inner pots are conductive and should transfer the heat to the rest of the pot. For some reason though, only the clad bottom of the inner pot is magnetic. I thought all stainless steel pots would be magnetic but I was wrong and found that out when testing the other cookers inner pots. Evidently the stainless steel which is used to make the inner pots have a high nickel content which makes them non-magnetic. Thermos by adding the clad bottom to their pots avoids the problem and should allow it to work with induction type stoves.
April 27, 2011 at 7:22 pm
Hi
(1) Is the stainless steel safe for cooking food with vinegar, tomatoes etc?
(2) For the Shuttle Chef that comes with 2 3-litre inner pots, is it ok to cook with only one pot ie to cook with only one pot in the outer pot.
Tks!
April 29, 2011 at 10:41 am
Stainless steel is safe for cooking high acidic foods such as tomatoes and using with vinegar. Vinegar should not be used in pots made of aluminum, iron, or copper.
It is OK to use a single 3-litre pot to cook in with the 6L RPC-6000 outer however, understand that the less food mass inside a pot the quicker the contents of the pot will cool down. So for recipes that take longer to cook you may likely have problems completing the cooking process without reheating the food mid way.
Also, when using a single 3L potr, it is necessary to fill the empty space inside the outer with a good insulator. One option is to place a good sized thick hot pad that can cover the whole 3L pot over top and then stuff a few thick dish towels inside to fill up any empty air space before closing the lid. The objective is to keep the heat inside the 3L pot. You can also fill the second 3L pot with boiling water and place it inside under the 3L pot you are cooking food in to act as a radiator of heat.
November 16, 2011 at 12:36 pm
I have searched in vein to find how much the unit costs – please help. Carolyn
November 16, 2011 at 7:46 pm
On the front page of this blog on the right hand column is a list of links to where you can buy and find the best prices on thermal cookers.
September 7, 2012 at 9:21 am
In your recipe, what size of pot do you usually use? 4.5 litre or 6 litre?
Thanks!
September 10, 2012 at 8:40 pm
There are a great number of recipes posted and there is no fixed answer for the size pot being used in any one recipe. I personally find that the 4.5L cooker serves my family well and will adjust recipes to fill it at least 3/4 full depending on the type of food makes up the recipe.
October 2, 2012 at 5:03 pm
I am trying and trying to make stock in my 2 gal thermal cooker. When I was doing it my crockpot I would leave it on for 24-48 straight. Now that I am using my termal cooker I have done it for 36 hours, re heating it every 6-10 hours. The results have been very dissapointing. Am I un realistic in my attempt to get a full bodied, gelatenous stock from the thermal cooker like I was achieving with my crock pot?
October 2, 2012 at 10:25 pm
Stock is not a recipe I’ve tried to do in my thermal cooker so I can’t answer your question with any experience. My guess is that the thermal cooker doesn’t allow the stock to thicken as much through evaporation as you are getting with the long hours in a crockpot. The water content will remain much the same even after many hours of cooking when using the thermal cooker which might account for the results being observed.
I’m not sure if starting your stock with less liquid would make a difference either. Does the stock remain the same consistency even after cooling?
You might ask this question over on this thread of thethermalcook blog: Master Stock cooked in Mr D’s Thermal Cooker
July 26, 2022 at 4:33 pm
My 12volt adaptor is not heating up My thermal cooker 24/7. Can someone please let me know what I should do
October 12, 2017 at 6:51 am
Emily, I think you and I have the same problem with our thermal cooker. Mine is a Thermos brand (supposedly a very good brand, if not the best) but it NEVER worked. I’ve tried different food, different texture: stew, soup, porridge, congee …. I even cooked the food for 30 minutes before putting the inner pot inside the outer pot, making sure it is hot enough and all ingredients cooked through. Every time the food did not continue to cook – many hours later, it’d look the same as before, very watery, and the meat still tough! It retains heat alright, because hours later, the food was still very hot, but simply not cooking further. It’s baffling and frustrating. And I have been very careful with the cooker. There is no scratch, no dent, no damage at all.
October 12, 2017 at 9:52 am
The Thermos thermal cooker is one of the best on the market and I’ve used mine with great success for years. Here’s some of the gotchas to look for and see if you’ve hit in using a thermal cooker.
* For foods that need a few hours of cook time to complete make sure your inner pot is at least 3/4 full of food and liquid. A partially filled inner pot will cool down too fast to continue the cooking process long enough to finish it. You might also need to leave the inner pot on the stove for at least 30 minutes on a simmer to help compensate for those harder or longer to cook recipes.
* After the food in the inner pot has reached a boil and simmered on the stove long enough for the recipe and is ready to be placed into the outer thermal cooker pot, don’t dilly daddle in the process, take the inner pot off the stove and immediately put it inside the thermal cooker and close the lid to the outer pot very quickly to trap as much of the heat inside as possible.
* If you find that your thermal cooker’s inner pot is too big or would hold too much food for the number of servings you want to prepare, then instead of placing the contents of your recipe into the inner pot itself, place it inside a smaller canning jar (or number of jars) or smaller stainless steel or glass container with a good sealable lid, then place the jars or container into the inner pot filling up the inner pot with water until the inner pot is completely full. Now, with the inner pot full of water and your recipe inside the jars or container place it all on the stove and bring it to a boil and then simmer as needed before moving it and placing it inside the outer thermal cooker. What this does is give you a lot more thermal mass in the boiling water which will hold onto the heat much longer and keep it hotter than a recipe that only filled up an inner pot part way. The other benefit to this is that once your meal is ready to eat, you can remove the jars or container from the inner pot but then close the lid to keep that water hot and use it after the meal to clean the dirty dishes.