DON’T JUST TAKE OUR WORD FOR IT!
The effectiveness of natural refrigeration dehumidifiers has been verified by independent testing:

• As noted by the U.S. Department of Energy… “The (mineral) works in concert with chillers to significantly increase energy system efficiency by allowing chillers to cool low-moisture air… (and)… can cut cooling loads and peak demand by as much as 50 percent.

• As noted by the Food Engineering Directorate, U.S. Army Research, Development and Engineering Center… “It is clear from these studies that ethylene absorber filters containing zeolite coated with potassium permanganate should be used in all fruit and vegetable storage areas in order to ensure maximum shelf life at an affordable cost.”

• As noted by the Townsend Letter for Doctors and Patients, October 2005… “Zeolite coated potassium permanganate reduced the aerobic bacteria growth count (for two apple sections refrigerated for 28 days) by a factor of 1000.”

The U.S. Army study excerpted below shows the effectiveness for other fruits and vegetables as well as the economic benefits, using a mineral mix very similar to RD FRESH.

USE OF ETHYLENE ABSORBERS IN EXTENDING SHELF LIFE John A. Ayoub, Dr. Margaret G. Driver, Dr. Irwin A. Taub FOOD ENGINEERING DIRECTORATE, U.S. ARMY NATICK RESEARCH, DEVELOPMENT, AND ENGINEERING CENTER

Nature of the Problem: Ethylene is a natural plant hormone produced by metabolism in most fruit.  It initiates and accelerates the ripening of fruit and causes vegetables to deteriorate. This unavoidable process is a major problem, since in almost all applications noncompatible fruits and vegetables (i.e., ethylene emitters and ethylene sensitive items) are stored and/or shipped in the same container.  If we could keep the level of ethylene as low as possible, we would be able to slow the maturation of the fruits, protect the vegetables, and reduce spoilage to a minimum.
 
Technical Strategy: One of the simplest ways to remove ethylene from the atmosphere is to absorb and oxidize it with potassium permanganate to produce CO₂ and H₂O
 
Field Test II (Korea by Surface Vessel).  This test was the most controlled of all the field tests to date. In cooperation with DSR-PAC in Alameda, CA, we set up a three-week shipping test to South Korea.  Large lots of FF&V were split and placed into two identical 40 ft. sea vans, one with and one without absorber filters placed near the air inlet to the cooling system operation at 36°F.  The produce was inspected by a Quality Assurance Specialist from DSR-PAC and a Natick Project Officer before loading in Alameda and after unloading from the container ship in Pusan, South Korea.  The atmosphere in each van was also sampled for the concentration of ethylene. Upon arrival in Pusan, the atmosphere in the test van with the absorber filters had an ethylene concentration of 1.8ppm, while the atmosphere in the control van had 29ppm (more than 16x the concentration).  The fruits and vegetables in the absorber-protected van were in excellent condition.  In the control van, many of the green leaf vegetables were completely spoiled and most of the fruits were ripe enough for immediate use.

Comparative Economic Aspects: In order to know the overall economic benefits of using ethylene absorbers, you have to determine the savings due to reduced spoilage and compare it to the cost of absorbers required.  Using the example of the shipment to South Korea, the estimated savings due to a reduction in spoilage at destination was $928 while the cost of the absorbers was $160, thus a net benefit of $768 (A 480% Return On Investment)

From the Townsend Letter for Doctors & Patients, October 2005

Objective: To simultaneously assess the rate of aerobic bacteria in 2 red delicious apple sections from the same apple, with and without proximal exposure to Zeolite-coated Potassium Permanganate.

Results: The exposed sample, following 28 days incubation, yielded 10,000 aerobic bacteria per milliliter count. Simultaneously, an apple section from the same apple was refrigerated for 28-days without exposure. This sample yielded a count of 10,000,000 aerobic bacteria per milliliter.

Conclusion: This shows that Zeolite-coated Potassium Permanganate reduced the aerobic bacteria (AB) proliferation growth count by a factor of 1000.