This topic may have been covered before, so forgive me if I am recycling it.
We are considering adding a freeze dryer. But, it is really expensive as everyone knows.
I can't convince my wife that we are going into a collapse/shtf/wrol scenario, so don't give me any arguments about needing 25 yrs of shelf life. Those arguments will fall on deaf ears. Can you give me some ideas if a food freeze dryer is worthwhile as compared to a food dehydrator all things being equal. Money is an object!
Apples to oranges. A dehydrator makes things leathery and uses heat. So some properties of whatever you're dehydrating will always be destroyed.
A freeze dryer is a completely different process with a completely different result. Show her the difference between a dehydrated strawberry (gross) and a freeze dried one (crispy delicious!)
But honestly, I don't think I could ever justify dropping the minimum 2k on a freeze dryer unless it was a business situation where I knew I'd make that money back over time.
Two words: freeze dried ice cream. I always try to bring some on canoe/hiking trips and it's a huge hit, though it's $4.50/oz. It could pay for itself right there!
I take both dehydrated (my own and purchased) and freeze dried meals on trips and the FD meals are better than the store bought dehydrated ones, though my home-made meals are the best. There's a big difference in energy requirements, though, between FD and dehydrated meals. The FD meals just need to soak in boiled water for about 15 minutes, while the dehydrated ones need to simmer, so there's a time issue too. I prefer to cook with fire, but that isn't always easy, so I bring FD meals and a stove with fuel for quick meals that use very little fuel. I'll often put dehydrated meals in a bottle in the morning with water to let them hydrate partially during the day to save fuel at night.
The texture, as Matt says, is much different, too. I've got a Cabela's 80 litre dehydrator, which can dry a crazy amount at a time and I put it on the lowest heat that I'm comfortable with, but it's still heat. From what I've read, the FD method loses less nutrition than dehydrating, though I'm not sure how big a difference it is. You can also build a solar dehydrator (plans on this site) with a huge capacity and no inputs, so there's that.
I have thought of a FD machine but, like Matt, I would be buying it to make FD meals for sale. You can buy FD strawberries from Mountain House or other companies, so your wife could try those and other foods compared to dehydrated meals. I've read, but have no experience, that you can FD a steak and then re-hydrate it and it'll be much like fresh. If you're handy, there are a few people out there with DIY FDers, so that may be an option too.
A piece of land is worth as much as the person farming it.
-Le Livre du Colon, 1902
I often think about how I would deal with a real bumper crop of perishables. Honestly, I am not going to outlay a huge amount of money, mostly because I don't have it.
My practical solution to this is to settle for what I can do myself, and not let the perfect be the enemy of the good.
If I could find really great plans to a Freeze Dryer that I could build myself from reclaimed, repurposed, and cheaply-bought, readily-available parts, I would choose that, as it's the nutritionally superior method of food preservation.
But if all I could find are plans and materials for a really great solar dehydrator, I would go that route. It might not be as versatile, and might not preserve all the nutrition, but it would keep my harvest from being lost to spoilage.
And at the end of the day, that's the goal.
A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects.
-Robert A. Heinlein
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