dehydrator and bacteria

[brendasue]

I was using my dehydrator this week and made some really good things but it got me thinking.

Food is in the dehydrator more than 24 hours in some cases, and at such a low temperature can’t bacteria grow?

It would seem to be the perfect situation.

Any thoughts?

BrendaSue

[katchmoleen]

I have thought about this and wondered why we all aren't getting food poisoning like crazy with all the soaking and dehydrating, but I believe it doesn't happen because fruits and veggies tend to ferment before they spoil. My experience is that the stuff I make and leave in the fridge too long actually ferments. You can taste it, and it is not always bad tasting, just different. So the fermenting bacteria rule over the rotting kind.

[DebB]

Hi Brendasue ~ This article (http://www.excaliburdehydrator.com/enzymes_and_thermostat_control.htm)on Excalibur's site might prove interesting. It's about halfway down the page in the section titled, "How Excalibur’s Thermostat Works" *Ü*

[RawKnitster]

Great article, Deb. That clears up my questions. I've read books from 3 other raw food authors that say to turn the temp on the dehydrator up to 145 for the first few hours, then turn it down to 110-115. Apparently not with an Excalibur. Those raw authors need to read this article.

Also good to know that enzymes can go dormant. I was under the impression that dehydrating too long would kill the enzymes, even at a low temp.

I think thickness of what you are dehydrating plays a factor as well. I'm pretty sure I've gotten a few nasty bacteria from dehydrating a bread recipe, and once from stuffed mushrooms. Both times the food was too thick to dry out in the time it should have.

[Aleesha Sattva]

where did it say to not turn it up? when i got my excalibur it suggested that i turn my dehydrator up for the first two hours, which i always do as it speeds up the process tremendously... i set my alarm for 90 minutes so i never leave it up high for too long. i think that's the key... to make sure you turn it down.

[RawKnitster]

"Therefore if you set your Excalibur at 105ºF you are setting it to hold the food temperature at around 105ºF, the air temperature may get as high as 125ºF depending upon the moisture content of the food."

"Ann (Wigmore) tested different dehydrators, and found that Excalibur was the best for living foods. She found that the best technique for saving enzymes was to set Excalibur on a higher food temperature setting in the beginning and then turn it down after a few hours. However because most people may not know when to turn it down, and by leaving it on the higher setting may kill the enzymes she said to set your Excalibur on 105ºF setting throughout the entire cycle. That way the food temp will never go above 120ºF even after it is dry."

Based on that I would conclude that setting the Excalibur at 135F could bring the air temp up to 20 degrees higher, or 155F. Might be okay if your food is still wet, but weigh that against the statement that enzymes are most likely to die off at high temps when wet....

I would be one of those people that forget to turn the temp down on time. I will keep mine set between 105-115.

[kyrie]

Hi Raw Knitser,

I've found that 105 degrees does not work. Unfortunately all I got was sick rotten food as a result. It really depends on where you live.If you live somewhere that is hot and dry, use 105 degrees. If you live somewhere wet and humid or hot and humid, 105 degrees equals sick sick sick.Raise the temp over 105 where appropriate,because the outside temp matters. One temp does NOT suit all, unless you're fond of gastro-enteritis and vomiting and stomach pains, and have tons of money to waste, or you live somewhere hot and dry and sunny.

Carla.

[RawKnitster]

Good point, Carla. :) I live in the wet Pacific Northwest and my dehydrator is in the basement. It is about 55 degrees down there today. During this past (very dry) summer it was about 75-80 in the basement and 105 was working, but now that the weather is cooler I've bumped it up to 115 and am getting the same results.

[anniez]

Good info here. Thanks. I think the key is experimentation to find what works for you. Also, everything that I dehydrate I keep in the fridge. Better safe than sorry.

Annie

[T-Bird]

Hi Raw Knitser,

I've found that 105 degrees does not work. Unfortunately all I got was sick rotten food as a result. It really depends on where you live.If you live somewhere that is hot and dry, use 105 degrees. If you live somewhere wet and humid or hot and humid, 105 degrees equals sick sick sick.Raise the temp over 105 where appropriate,because the outside temp matters. One temp does NOT suit all, unless you're fond of gastro-enteritis and vomiting and stomach pains, and have tons of money to waste, or you live somewhere hot and dry and sunny.

Carla.

So basically, are you raising the temp high enough to kill bacteria? or just shortening the drying time dramatically?

Like rawknitster, I only do 105-115, I've also done dehydrating in the fridge.....it works, but takes some time.

In a humid situation, I'd focus in on water removal rather than upping the temperature.

I'd either try to enclose the dehydrator and a room dehumidifier in a fairly enclosed space, or use a combo of refriderator and dehydrator.

[T-Bird]

on another note, sometimes I look at all the fresh lovely food I pulverize and then lay out to sit in warm air for about a day to "stalize" and lose the fresh glow......is it stealing the glow from me???

Just wondering....I eat about 70-80% fresh. But wondering exactly how that other 20-30% impact the overall.


ETA: this came up recently when I made some root veggie burgers, which for the first time I included beets, and it made them a bright peptobismal pink. Within 2 hours in the dehydrator, the color was a ruddy brown, and I wondered what the food had lost so quickly...

[anniez]

ETA: this came up recently when I made some root veggie burgers, which for the first time I included beets, and it made them a bright peptobismal pink. Within 2 hours in the dehydrator, the color was a ruddy brown, and I wondered what the food had lost so quickly...

I think it oxidized. Was it tightly covered?

Annie

[T-Bird]

I think it oxidized. Was it tightly covered?

no it was not tightly covered in the dehydrator....it would not then dehydrate.

The point was - what does it loss, nutrient-wise, in the dehydrating process, and I used this as an example...

[anniez]

Sorry, I misunderstood, I thought it changed color after the dehydrating. Nutrients are not supposed to be lost if it's under 115 degrees.

Annie