Dehydrator temperature disagreement

[anthony11]

I've read raw/living food people give a variety of temperatures to not exceed when heating raw/living foods. Some sources say 95F or 110F, others up to 150F, which would emcompass the Manna/Essene breads, even the commercial ones.

Now the booklet that came with my shiny new Excalibur says "When raw food is heated to an internal food temperature of 118F or higher, for an extended period of time, its nutritional values begin to deteriorate, especially the unspecified "enzymes". This phrasing makes me wonder if warming up broccoli a bit would be all that bad.

It goes on to recommend setting the unit on the highest temp for 2-3 hours, then setting it down to <120 for the remainder, saying that during the intial hours the food temp won't exceed 118F because of moisture content. That seems somewhat plausible to me, given what I know about Heat of Evaporation in a chemistry/thermodynamics sense. I also wonder if the prolonged exposure of going at a lower temp from the beginning isn't just as damaging or even more so than a shorter exposure with a briefly-higher inital temp.

Thoughts? Analysis-based references? Jeers of derision?

[deedub]

I have the book Rainbow Green Live-Food Cuisine by Gabriel Cousens, MD., etal and he recomends setting the dehydrator on 145 for a maximum of 3 hours and then cut to a "normal temp of 110-115 degrees. He says the dehydrator mfg. actually suggest this. He goes on to talk about bacteria and also that the emzymes are more likely to be destroyed the longer the food stays in the dehydrator. He also says what you said about the internal temp of the food being 20-25 degrees less than the gauge.

[anthony11]

I have the book Rainbow Green Live-Food Cuisine by Gabriel Cousens, MD., etal and he recomends setting the dehydrator on 145 for a maximum of 3 hours and then cut to a "normal temp of 110-115 degrees. He says the dehydrator mfg. actually suggest this.
Yep, that's about what Excalibur says in their booklet. I smile whenever I see his surname spelled incorrectly, as I know what that's like.

He goes on to talk about bacteria
Thats one thing that worries me, too. It used to be widely thought that bacteria were killed at a relatively low heat, or by freezing, but as we discover increasing numbers of extremiphiles, I wonder about that. Heck, there are tube worms that tolerate a 100F gradient along their length, bacteria that live at or above the boiling point of water at sea level (though they're under more pressure), etc. And of course it's nice to have a bit of margin, too, to allow for uneven heat distribution, etc.

and also that the emzymes are more likely to be destroyed the longer the food stays in the dehydrator.
That makes lots of sense to me -- when I see recipes calling for 20 hours of dehydration at 95F, I have to wonder a bit if I'm incubating at the same time.

He also says what you said about the internal temp of the food being 20-25 degrees less than the gauge.
The booklet does mention a Dr. Edward Howell, Ann Wigmore, and Viktoras Kulvinskas wrt these temps.

Thanks for confirming that this is good practice.

[Rossk]

so to clarify lately i use my fan oven which can start very low at the lowest temp around the 60-80 for a couple of hours like 3 or 4 , would I be be better off a tiny bit higher for a little less time ?
Or this such a small thing it wont make much difference

[Rossk]

so to clarify lately i use my fan oven which can start very low at the lowest temp around the 60-80 for a couple of hours like 3 or 4 , would I be be better off a tiny bit higher for a little less time ?
Or this such a small thing it wont make much difference

[Rubyred]

Hmmm... I have some recipe books that tell me to start at 145 degrees for an hour, then move it down to 115 for the remainer of the time. It sounds reasonable to me.

For the record, I have a Excalibur 4-tray dehydrator. At first food dehyrated pretty quickly, but then it seemed to take forever. I put 2 thermometers in there and found the temperture was about 10 degrees below what the guage said. The food just seems to come out better when its dehydrating at 110-115 degrees.