Backpacking Discussions

Freeze-drying: Food is rapidly frozen then placed in a strong vacuum. 98 percent of moisture in the food is removed as vapor through sublimation and as a result the food weighs significantly less then the original item. For example, 3kg of chicken weighs only 1kg after freeze-drying, and rapidly rehydrates back to its original weight. Freeze-drying uses low heat and causes little damage to the tissue, taste or aroma. Products easily restore and closely resemble the taste, texture, and nutritional content of the original food. This is not commonly done by backpackers themselves, since the process is very time consuming and requires large, expensive machinery. Basically, freeze-drying removed the water and not the taste, and can be restored once water is added again.

Dehydration: Dehydrated Foods are top-quality foods, that have been picked at their ripeness; cleansed and trimmed to leave only the best parts. These choice foods are then dehydrated were 98% of their moisture is removed. This is done by a sophisticated drying process. Heat is applied to a food, removing the moisture through evaporation. Yet drying does not affect the nutritional value of these foods. Dehydrated foods retain their nutritional value because the vitamins have not been cooked out in the original process. The water, pits, and peelings have been removed and you pay only for the product, not excessive or unnecessary waste material. This is the preferred drying method for some foods, including onions, peppers and tomatoes. Dehydration is a lower cost method and results in a more compact product. Because their bulk and weight have been greatly reduced, dehydrated foods are more compact and convenient for storing since they require very little space. For example, one case of regular canned food weighs approximately 24 pounds. The same item of dehydrated foods would weigh around 40 ounces, and would be packed in just one #10 can. Dehydrated foods have approximately double the yield of regular canned foods even though their cost is much lower.

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Both dehydrated and freeze-dried food items can be purchased many places online and at local stores, but I'd recommend Wilderness Dining.

I've always wondered what the difference between freeze-dried and dehydrated is. Thanks for the great information!

'Freeze-dried vs dehydrated' is a common question that most beginning backpackers have. This is a great post Colton, thanks! I thought I knew about this already, but I didn't know that once you refresh the freeze-dried foods, they get their nutritional value back and that dehydrated foods retain their nutritional value! Thanks.

I also didn't know that freeze-dried foods get their nutritional values back, that's surprising! And good to know! Thanks for the great article.

Great information! Thanks! I've never really known the difference, so good to know.

mmmmmmmmm

freeze-dried beef jerkies

mmhmm that does sound good. haha

Thanks you guys, and if you have anything to add, please do!

Just made a post on Outdoor High Adventure's new blog, backpackingrecipes.wordpress.com, about the differences between freeze-drying and dehydration. Check it out and leave some comments!

Oh cool. Thanks for the link. Great blog by the way!