Tuesday, September 24, 2019

My name is Joe. I burn applesauce.

My name is Joe and I burn applesauce.

I don't always burn applesauce. Sometimes I can suck-it-up and not burn it.

But then I push the envelop. I turn the heat just a little higher. I use just a tad less water in the bottom of the kettle. I add a few more apples.

And then I burn the applesauce.

The batch of apples I was cooking down to mush is ruined.

The kettle is impaired. I have to scrub, and scrub and scrub...and even then apples cooked in the kettle pollute future ventures.

I am also an engineer

In theory, a double-boiler where the intermediate fluid has a boiling point significantly above the boiling point of pure water but far below the temperature that scorches apples would create a very robust process.

Commercial canneries use pressurized steam. Water is cheap but equipment is not. The fixed costs of the steam equipment is amortized over enough volume that it become insignificant. That is not the case for the typical, home canner.

The next best thing would be to use an ethylene glycol-water solution as the intermediate fluid. My first swing at the pinata was to use a 2/3 EG:1/3 water solution with a boiling point of 236F...almost 25 degrees higher than pure water.

My concern was that the EG:water solution would boil and over-flow into the apples, thus contaminating them.

I investigated that concern by performing a trial run with the EG-H2O solution and using a full kettle of pure water as the test load.

This is what I found.

A turkey fryer. Nominally 55k BTU/hr. Sides modified to accept larger diameter double boiler. I cranked it up as hot as it would go to give it a severe test.

Three nuts to hold cooking vessel away from the bottom of the double boiler.

1.5 gallons of 65%:35% antifreeze:H2O. Large kettle has ID of about 15.5 inches. Smaller kettle has ID of about 11.5 inches.

Started at 11:36 AM. H2O payload hot-to-touch at 12:06. Antifreeze:H2O heat-transfer fluid bubbling at 12:11. H2O in cooking vessel at rolling boil at 12:20.

The primary concern was that the heat transfer fluid would bubble up and contaminate the apples being cooked. This photo shows the amount of rolling of the heat transfer fluid when the water in the cooking vessel was at a full, rolling boil and the turkey fryer LP burner was pegged.

The results of this trial run are promising enough to redo the experiment with real apples.


  1. We use a large steamer, the kind asians use for rice or steam buns to make apple sauce without schorcing. You end up with a couple quarts of apple flavored liquid when you are done.

  2. That's why l buy the stuff... LOL

  3. Isn't ethylene glycol a deadly poison that shuts down kidney / liver function? The chance of toxicity transfer even if remote would far too high for my risk portfolio.

    1. Commercial antifreeze has bitter added to it. Lowest lethal dose for a 150 pound human is approximately two ounces.

      A batch runs about 14 quarts of finished applesauce.

    2. I take your point but I think I would still opt to use cooking oil kept just about 100°C, and just get a big double boiler at a used restaurant-equipment store.

    3. I like the idea of capping the eg:h2o with vegetable oil.

      Antifreeze also comes in a non-toxic Kolbian Orange version.

      The advantage of the antifreeze:water mix is that it hard-stops the high temp at the boiling point of the mix.

  4. Start running a timer. Stir when it goes off and it will never ruin again. I like the homemade double boiler and that should solve your problem too. Antifreeze near the edibles is a nogo!

  5. Get a he induction burner. The free standing ones(think hot plate) don't have a lot of power, but they are great at temp control.
    Put a pan of water on at 210 and it simmers, turn it up to 220 and it boils.

  6. A big Crockpot is what I use. Boil the cored apples until soft enough to go through a mill, mill them removing the skins and hard bits, transfer to crockpot, season and add time.


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