About Freeze Dryers

Hi Kevin,
We are still not here all 7 days of the week to be able to keep things consistently watered. Rabbits and deer out.
So in the old ground level 4 foot by 4 foot planter boxes we are just trying out different things to verify full seasons sun angles; frosts spreads; area molds and rusts problems.
Next season we will be able to get back to growing storable qualities versus just fresh picked eating.
Got a whole empty freezer to re-stock and 500-600 canning jars empty:

But I’m thinking like Dean Lasko has done now getting a foods vacuum freeze dryer system.
Hot jars canning is a lot of work in the hottest time of the year.

Old now; we just don’t do summer heat canning seasons, heat nearly as well.
Steve Unruh

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Freeze dryer is definitely the way to go but my pockets are just not deep enough. Absolutely the best way to preserve food though. I’m not hanging all my hopes on a seasonal garden anymore. Last couple years I’ve been slowly experimenting on growing indoors with grow lights. You can grow more than you would think in a small area. Especially root crops.

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True.True by far on the price for any size of those Golden Harvest vacuum foods freeze dryer systems.
I’ve watch a number of videos and pick this one as the guy did seem to addresses that, the pro and cons, and show long term storging in glass jars with metal lids caps. Solving the plastics problem.

Not saying I’m pulling the trigger quite yet myself.
Still . . . . that emptied freezer I pictured shown. … got that way by me dumping out ~500 pounds of foods.
For a long time my wife’s family had FOUR chest freezers. One each for previous years meats. Another for previous years vegetables and fruits. Then another pair emptied for the upcoming years new fruits, vegetables and new meats. They fed a base of four people out of those. Gifted frozen foods to visiting relatives. Gifted foods to needing in the surrounding community - had to be families with children.

Those gifted out sealed in double wrapped freezer papers, and double plastic bags. They thought this was much better overall for the time efforts spent versus the their lifelong previous heavy heat process canning in jars.
Gifted out food never more than 50% of those expensive glass jars ever came back.

My older sisters family branch went heavy from heat jars canning into freezing using Seal-a-Meal systems. Those sealers were tricky to use. Wore out needing replacement. The plastic sealer bag stocks very specialized, and expensive, A one-use then landfill trash system.

And those big capacities home freezers while not gross energy gobblers . . . it does add up. At our current grid rates that were 7 cents a kW/hr now crept up to 11 cents a kW/hr works out to an average of $5.00 to $9.00 a month per freezer, annually. Once the second of Wife Melinda’s parents passed-on I immediately cut back to only using two chest freezers.
Then my huge mistake was moving them out of house into an old building “Freezer shed”.
The idea you would once a week restock the in-house refrigerator freezer section. Well that seldom happened. And I’ve dumped for the chickens; and buried hundreds of pounds of ten year old foods. Then Freezer burnt and tastes changed. What a crying shame waste of power, plastics, let alone the hours and hours foods prepping to store.

So in relationship to the Wife’s every 4-6 weeks hair dresser appointments . . . me buying $1,000+ electrical generators; another rifle; another pistol . . . other fellows spending out on streets hot-rods, weekly Lotto tickets and stadium sports enthusiasms a Golden Harvest machine purchase can seem sensible.

The actually BIG downside as I see it is the processing time/caspacity. In a two year later video he shows the newest as of this year; up to 30 pounds a cycle oversized XL Golden Harvest model. Better at a 24-30 hours in-process cycling time. So figure a realistic 40 hours cycles for trays clearing to jars; internal and trays cleaning up and sanitizing. So four: 25-30 pounds a week in make-storable capacity.
When many of the fruits in particular, or meats acquired, slaughtered, you will have a once a year hundreds of pounds needed to get done NOW, in 2-3 days at the most.
Hot jars canning that can be done.
Wrapping/bagging freezing that can be done.

So a vacuum freeze dryer as a could be used some-times addition. . . . that is when the buy-in is hard to justify in my mind.

Now that is really Living a Good-Life puzzling out these decisions!
Vesus the true plastic lives most are sucked up into now. Sheez. The home all-entertainment packages most of my family now contrast and compare are $200.+ a month. $2400. a year to be captivated mesmerized for a quarter of each and every day!
That set of new 20-22" wheels and tires bought just to look Kaw-ool. $2400.

S.U.

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I was always thinking about DIY dryer based on heatpump made from fridge compressor. At evaporator side, vapor from food condense and dry cool air is heated at condenser part. Water collected may provide additional cooling for compressor. The temperature of drying air would be low which preserve the quality of food.

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STILL a great option for food storage- if you can get a good warrentee on a freeze drier- since it keeps the nutriants and flavor so well.==or i might be proned to build one as kamil-k was thinking

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You will need a vacuum pump as well. Freeze drying is a result of both low pressure and low temperature.

This guy used a freezer, a wine saver vacuum pump and dessicant. but it took him a couple of weeks.

There is another video and the guy used dry ice, but he noted using a deep freezer (which is short for a commercial quality freezer that is capable of lower temperatures) would be better.

I guess the point is the fridge compressor may not be able to get cold enough, but it could be used as the vacuum pump.

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Oh, I never think of freeze dryer. It’s just common hot air dryer, but with closed cycle between hot and cold side of common refrigerator cycle. The idea is just to make it more efficient and shorten the drying time.

For freeze dryer, any temperature bellow zero should work with aid of vacuum. Its the pressure what plays the key role. Triple point of water is at 600 Pa pressure. You would need quite good pump to maintain this low pressure.

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Okay. I think there are two steps to this. The first is you have to flash freeze. The flash freezing process doesn’t burst cell walls because only micro-crystals of ice will form. Otherwise the slower freezing process bursts the cells walls and makes it mushy.

Then you apply the vacuum to dry it. I think the cheap two-stage HVAC pumps actually get enough vacuum. This vevor one lists 2.5pa or 20 microns (20 microns was listed what was needed for a laboratory sublimation chamber)

then you need a vacuum chamber like a modified pressure cooker, or vevor has a vacuum pressure pot for like 70 dollars.

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Kamil, I am of the same opinion as you, the condensation dryer is probably the most efficient and economical, if you do not have excess thermal energy. As I already mentioned, years ago I worked in a company where we were engaged in the production and servicing of cooling systems, we also produced condensation dryers for wood (or some other material,… corn, wheat, buckwheat,…) The procedure is very simple, an isolated closed space where the material for drying is located is heated to 40°C (depending on the requirements), well, the air from this space is partially led (approx. 30-40%) through the refrigerator, where it cools down to low temperature (5-10°C), so the water condenses and drains. This cooled and dried air is then mixed with 60-70% moist air, which is heated on the lamellas of the condenser, which is blown back into the dryer room.

Another sketch of the system…

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Freeze dryers have a lot of benefits in my opinion, but only on small amount of foods. Some delicate fruits and vegetables etc but thats about it. No sence freeze drying meat per instance, smoke dryed meat is tastyer and will last just as long. Mushrooms must be sun dryed. They become more nutritious that way (produce vitamin D). Tomatoes also bennefit from the sun. Untill the cost of freeze dryers falls to digestible levels l swear on the traditional methods

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Drying foods is a major part of my prepping Whether SHTF or not. In the event the grid was gone I would have no options. I have built a solar dehydrator but our constant 50 plus humidity kept that from working. May have worked better if I would have had a PV powered fan to force air through the thing instead of just convection. Using wood supplied heat for most things other than leaf crops is very problematic. Without being able to maintain a temp in the 105 to120 F. range most vegetables will tend to case harden and be unstoreable. Too much time involved and power required for off-grid supplied electrical. With our humidity levels my average run time for things like carrots, cukes and potatoes is at least 10 hours. I don’t know how long a freezer dryer requires to run a batch.

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I have a freeze dryer, for these reasons: 25+ yrs. storage, retains 97% nutrition. Dehydrators 70-85% canning 50-70%. We freeze dry almost everything, tomato, and egg powder very easy to use.

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What is your average run time and power draw Al? The 25 year shelf live has no interest for me. If I’m still here in 25 years I’m going to be severely pissed.

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Is it feasable to freeze dry milk Al?

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This guy says, YES, four years ago:

I’m sure other users have videos can-do too.
He has a much more recent video doing 50 gallons and may have refined his methods.
S.U.

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Ya there’s lot of channels out there, this is a good one, he can get very technical on stuff, but here he explains the basics of freeze drying.

I’m just a beginner on this but we did about 500 hr of freeze drying on the machine hrs and meat does very well, we did raw pork loin chops,hamburger patties,and chicken and they turned out good, when we reconstituted them in water and cooked them they have same taste and texture, and it frees up freezer space, just put them in tub on shelf.
Ps freeze dried ice cream is the best.

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This diagram is missing here to understand the natural properties of water.

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This looks like an extract from a mollierdiagram on only the curve of saturated steam/boiling point, at least the curve between liquid and gas.
Very handy for this discussion

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What are your findings as far as length of processing time for various crops and power draw Dean?

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Moved this to its own topic. Very timely discussion, I was considering these as well. Big spend, excellent payback.

One warning I’ve seen - do NOT eat freeze dried fruits directly. They are incredibly sweet with concentrated fructose, and just as bad for you as candy, possibly worse. Rehydrate them first and use them in cooking, fine. In general I think reconstituting freeze-dried foods is a better idea than eating the dried concentrates.

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