Why Freeze Dry?
We are often asked why our food is freeze dried as the method can be both time consuming and expensive. After careful research and analysis we settled on this method for a number of reasons.
Freeze drying extends the shelf-life of food without the use of preservatives while maintaining the quality.[1] Micro-organisms need water to survive. Once sealed, freeze dried foods are shelf stable for at least a year, some for up to 5!
The ability to completely rehydrate the food makes it a fantastic go-to feeding alternative.[2] Because freeze dried foods are exceptionally porous, complete re-hydration is possible
No need for chemically added vitamins and minerals. Recent studies have found freeze drying preserves colour, flavour, taste and the nutritional value without damaging protein structures and retaining the fat-soluble vitamins A and D.[3]
Digestibility of amino acids exceeds 90% after freeze drying.[4] according to researchers at the University of Illinois at Urbana-Champaign in the United States and the University of Guelph in Canada
Therefore, integrity of the vitamins and minerals is maintained… you get out what you put in.
FREEZE DRIED VS DEHYDRATED OR AIR DRIED?
Unlike both dehydration and air drying which use the application of heat, freeze drying does not require heat. One study done by the University of California, Davis found freeze drying retains 97% of the source nutritional value compared to only. 50-60% from dehydrated foods.[5]
HOW DOES FREEZE DRYING WORK?
Freeze drying, also known as lyophilisation, is a low temperature dehydration process. The food is first frozen so all water content Is turned to ice. In a vacuum chamber, cold and pressure are introduced effectively turning the ice directly into water vapour. This vapour then condenses onto a freezing coil thereby removing the moisture while leaving the protein and amino acid structures intact.
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[1] Ratti, Cristina (2008-11-21). Advances in Food Dehydration. CRC Press. pp. 209–235. ISBN 9781420052534.
[2] Ratti, C (2001). "Hot air and freeze-drying of high-value foods: a review". Journal of Food Engineering. 49 (4): 311–319. doi:10.1016/s0260-8774(00)00228-4
[3] Ma, Y., et al., 2018. Key composition optimization of meat processed protein source by vacuum freeze drying technology. Saudi J. Biol. Sci. 25 (4), 724–732
[4] Roji Balaji, et. al., 2021. “Recent Developments in Freeze Drying of Foods”. Innovative Food Processing Technologies: A Comprehensive Review (3) Elsevier, 82-99, doi:B978-0-12-815781-7.00017-2
[5] Barrett, D.M. and Lloyd, B. (2011), “Advanced preservation methods and nutrient retention in fruits and vegetables”, University of California-Davis Cooperative Extension
