Excalibur's Statement about Thermostat
Inaccuracies
The article below was provided
at the International Living and Raw Foods festival. DiscountJuicers.com was a
presenter and exhibitor. This information is being shared with our friends, our
customers. Thank you for your patronage.
Dear Excalibur Owner,
In the past couple of years as the raw food lifestyle has become more popular, some raw
foodists have become concerned about thermostat in their Excalibur not holding an accurate
air temperature. This concern has arisen due to a couple of reasons. One reason is the
lack of instruction we have provided on how the dehydrator was designed to work, which
then leads to the second reason, which is a lack of understanding on the part of the user
on what is happening during the dehydration process, and how the enzymes are effected by
various temperatures. Because of this concern parts of the raw food community have urged
us to design a new dehydrator with a thermostat that will accurately control the air
temperature.
One of our main goals as a company is to
produce a product that meets the needs of our customers. Therefore we responded to the
request and spent hundreds of hours testing at least a dozen different thermostats. Twice
we thought we found the right one, and both times they failed to get the approval of the
raw food chefs that tested them. They simply said the old one worked better. This created
a concern for us because we had based our decision upon inaccurate information, for
example that temperatures above 105 F would destroy all enzymes. We then devoted our time
and effort into finding the information we had to have before we could proceed with
developing a new product. Based upon what we already knew from almost 30 years of
experience, and information we found through recent testing and research, we have
discovered that Excalibur’s present design and thermostat is superior for living
foods.
The Excalibur Dehydrator’s thermostat
was never originally designed to hold an accurate air temperature, but was specifically
designed for, and very accurate at controlling food temperature. However it is very
important to understand what is happening in the dehydration process. Here are some
aspects of the process that are most critical to understand: FIRST,
understanding the difference between air temperature and food temperature, and how the
evaporation process keeps food temp lower than air temp, SECOND,
understanding how the thermostat works by causing the air temperature to fluctuate up and
down. and THIRD, understanding at which point in the dehydration
process that the enzymes are most susceptible to destruction by heat, which is while the
food is in its wet state. After the food is dehydrated the enzymes can with stand much
higher temperatures.
In understanding the difference between air
temp and food temp it is important to know how to read Excalibur’s dial. The
temperature reading on the dial refers to FOOD temperature . In
general food temperature is about 20 degrees cooler that air temp. Therefore if you set
your Excalibur at 105 you are setting it to hold the food temperature at around 105
degrees, the air temperature may get as high as 125 degrees depending upon the moisture
content of the food. The reason the food temperature is cooler is because of evaporation.
As the moisture on the surface of the food evaporates, it cools the food keeping it about
20 F cooler than the air temperature. We have discovered this through hours of testing by
measuring the air temperature and food temperature simultaneously during the dehydration
process using a Doric Trendicator with type j thermal couples.
It is also important to know how the
thermostat works. We have found through experimentation, that in order preserve the
enzymes, and reduce the risk of mold and bacteria, it is necessary to
have a wide fluctuation in temperature. Because enzymes and microorganisms both thrive at
the same temperature, we must be able to accomplish two things at once, keep the food
temperature low enough not to harm the enzymes. and elevate the air temperature high
enough to remove the moisture quickly to stop the growth of mold or bacteria. The wide
fluctuation in temperature accomplishes just that. As the air temperature rapidly rises to
its high point moisture is quickly evaporated off the surface of the food, and as the
temperature lowers the dryer surface pulls moisture from the center of the food and
becomes saturated again. Because of the continuous up and down fluctuation in air
temperature, and constant evaporation the food temperature remains constant at a lower
temperature. After all the moisture is evaporated out of the food. the food temperature
will rise and then equalize somewhere in the middle of the air temperature fluctuation.
Once the food temperature rises one might get worried and think that the enzymes are dead
if he or she does not understand the third critical aspect. Which is, that enzymes are
only susceptible to damage by high heat when they are in the wet state, therefore once the
food is dehydrated the enzymes have become dormant, and can withstand much higher
temperatures. According to our discussions with Viktoras Kulvinskas on this matter he said
that we were right, and that, quote: “dry enzymes can survive well up to 150 deg
F.” He has tested food he has prepared in his Excalibur dehydrators with an
experiment he created, and found it to he high in enzymatic activity. We have also done
some experiments by soaking various seeds. dehydrating them at different temperatures. and
soaking them again afterwards to see if they will sprout. and they did, which proves that
the enzymes are alive.
Something that has caused us a lot of concern
is we have heard so many conflicting opinions as to the temperature at which enzymes are
destroyed. Twenty years ago Ann Wigmore spoke to Roger Orton personally and said that the
food temperature had to go above 120 degrees for a period time before the enzymes were
destroyed. Again in our discussions with Viktoras he said the same thing. Ann 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 105 degree
setting throughout the entire cycle. That way the food temp will never go
above 120 even after it is dry. We believe this is why many have come to believe that 105
degrees air temperature is the temperature at which the enzymes are destroyed. which is
entirely inaccurate. We have also heard many people quote Dr. Edward Howell where he says
in his book “Enzyme Nutrition” that prolonged temperatures over 118 F will
destroy enzymes. We also read in his book where he says that the enzyme amylase can still
convert starch to sugar at air temperatures up to 160 F but will wear out after a half an
hour. We have also read where he says that the optimum temperatures for enzymes are 45 F
to 140 F. Just recently we spoke with Dr. John Whitaker who is a world recognized
enzymologist, and former dean of the Department of Nutrition and Food Science at U.C.
Davis. He said that every enzyme is different and some are more stable at higher
temperatures than others but that most enzymes will not become completely inactive until
food temperatures exceed 140 to 158 F in a wet state.
We appreciate you taking the time to read
this valuable information, and urge you to help us in spreading it though out the raw food
community. Please stop by our vendor booth if you have any questions, or you know of any
further information you can share with us. I will mention again that we want to meet the
needs of the raw food community, and are still open to making a change if necessary, hut
from what we have been told the present Excalibur is perfect. We hope that it has helped
in answering your questions regarding your Excalibur Dehydrator. Please share this with
any of your friends that have expressed concern about the accuracy of their dehydrator.
Sincerely,
Your Friends at Excalibur
