Reducing the Boiling Temperature for Tomatoes by Using a Vacuum - Ask Extension
Instead of boiling tomatoes for hours on the stove top to reduce them to make tomato sauce, can one reduce the boiling temperature (and save energy) b...
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Reducing the Boiling Temperature for Tomatoes by Using a Vacuum #424280
Asked August 30, 2017, 12:39 PM EDT
Instead of boiling tomatoes for hours on the stove top to reduce them to make tomato sauce, can one reduce the boiling temperature (and save energy) by using a pot that can be evacuated, thus reducing the boiling temperature, possibly to room temperature? Note that I don't know if such an apparatus exists, even if this is possible. If so, where does one acquire such, and do you have processing guidance for using this method? Also, I assume that the sauce would still have to be raised to a sufficient temperature to kill bacteria during the final canning process.
Union County Oregon
Expert Response
I have to say that personally I have never heard of a pot like you describe for home use. That said there may be one but I am not familiar with it. The problem also is there is no research base that I am aware of for how you would heat the tomatoes and then process them to make the sauce safe.
There are several methods of cooking your sauce that help reduce the moisture level you might like to try. For smaller quantities you can use your microwave and bring the tomatoes to a boil and then reduce the heat to lets say about 30 percent (defrost setting) and continue cooking to thicken the product to your liking. It won't scorch in the microwave, but you might cover it with a paper towel to prevent spattering.
Another way is to cook your tomatoes in a steam juicer. This will reduce the moisture in your tomatoes and the clear liquid that comes from the tomatoes makes great soup stock. Another suggestion is the slow cooker on low with the lid ajar. Some people also cook it on a low setting in roaster pans in the oven.
Hope this helps. If you have other food preservation questions you might like to call the OSU Extension Food Preservation Hotline open M-F 9 am - 4 pm Certified Master Food Preservers are available to answer your questions. The number is <personal data hidden>.
Thanks for using Ask an Expert
Nellie Oehler
There are several methods of cooking your sauce that help reduce the moisture level you might like to try. For smaller quantities you can use your microwave and bring the tomatoes to a boil and then reduce the heat to lets say about 30 percent (defrost setting) and continue cooking to thicken the product to your liking. It won't scorch in the microwave, but you might cover it with a paper towel to prevent spattering.
Another way is to cook your tomatoes in a steam juicer. This will reduce the moisture in your tomatoes and the clear liquid that comes from the tomatoes makes great soup stock. Another suggestion is the slow cooker on low with the lid ajar. Some people also cook it on a low setting in roaster pans in the oven.
Hope this helps. If you have other food preservation questions you might like to call the OSU Extension Food Preservation Hotline open M-F 9 am - 4 pm Certified Master Food Preservers are available to answer your questions. The number is <personal data hidden>.
Thanks for using Ask an Expert
Nellie Oehler
