So I bought a freeze dryer.
It’s quite sublime.
And in this video I intend to tell you all about the process of freeze drying.
Then, of course, I’ll show you the parts of this machine and explain how they work together to turn ordinary ice cream into astronaut ice cream—
and it’s not just a dry subject, it’s cool, too.
And it will leave you gasping for air!
But first a friendly word of warning:
unless you want to absolutely wreck your YouTube recommendations,
do not, under any circumstances, click on any recommended videos you may see next to this one about freeze drying or freezer dryers.
You will open quite the rabbit hole which, unless you’re big into the prepper community,
ya might regret!
And on that note, it makes me wretch a little bit whenever I say it out loud but I do know that I am an infl-
[shudders]
An influen- [nearly barfs]
oh I hate it so much -
An influencer.
But I’m really not about people wasting their money so I’m gonna come right out of the gate and say
you should almost certainly not buy one of these.
And to be clear, not because it’s a bad product!
This is not - I have relatively few complaints about this thing.
It works reasonably well and honestly I think it’s actually pretty remarkable that it’s a product you can buy and have in your home.
But it’s just way too expensive to be a rational purchase,
and if I didn’t have this job where I get to tinker with cool stuff and make videos about it all,
I know with certainty that I would absolutely regret spending the money I spent on this machine.
I won’t bury the lede,
this was nearly $3,000 which is way too expensive for what I think is mostly a toy,
and if you’re earnestly looking to store large amounts of food for long-term safe keeping,
I think you’ll find much wiser and much less irritating ways to spend your money —
and time.
But we’ll get to that later.
First, what is freeze drying?
Also known as lyophilization or cryodesiccation
it’s a process of removing moisture from, well, technically anything but most normally food.
And we do it not just because it does funny things to food - though that’s certainly one of the reasons -
but also because it prevents spoilage for incredibly long periods of time.
Food spoilage typically happens thanks to one of two things:
oxidation of fats and oils can turn some foods rancid, and since there’s oxygen in our atmosphere that tends to happen with time.
But more pertinent to freeze drying,
just as you and I gotta eat, the world’s microorganisms like bacteria and mold do, too.
And they’ll happily chow down on the same foods we eat,
decomposing them in the process and in many cases leaving that food unsafe for us to eat.
Those microorganisms, though, don’t just need food to stay alive; they also need water.
So if you can remove enough moisture from a food product, you’ll end up with food that’s simply too dry for those microorganisms to exist on -
and so, it doesn’t spoil.
Now there are plenty of ways to make that happen:
you’ve probably seen food dehydrators which turn fresh fruit and vegetables into…
dried fruit and vegetables.
And once dried, that food is much more resistant to spoilage from microbial growth.
But that process uses heat, and adding sufficient heat energy to dehydrate foods in our atmosphere
ends up changing the molecular structure of some food components which alters not only the nutritional value but also the taste.
Now there are plenty of food preservation techniques out there.
There’s canning,
there’s home canning (though personally I find calling that canning to be somewhat jarring),
there’s curing,
there’s pickling,
there’s fermenting,
there’s freezing,
and a lot of other stuff which we don’t have time for but most of those techniques end up doing something
which messes with the flavor, structure, and nutritional content of the food.
In many cases it does pretty cool stuff - a lot of preservation techniques impart unique flavor profiles that we actually like!
And there are endless cultural traditions out there which stand the test of time on flavor alone.
But if you’re looking to preserve food without actually affecting its flavor or nutritional content, well your options are limited.
That is, of course, unless you do a little cryodesiccation.
You know about dry ice, right?
Dry ice is the solid form of carbon dioxide, and it has a peculiar quirk.
It doesn’t melt into liquid.
Instead it sublimates directly from the solid form into the gaseous form.
That’s why we call it dry ice - it’s ice (though, extremely cold ice) which can’t get anything wet because it doesn’t melt.
It just shrinks.
Now, usually, you can’t get water to do that.
Water is wet -
or, or does it make things wet? Are we settled on that?
Anyway, frozen water doesn’t sublimate into water vapor, it melts into liquid water.
Don’t take my word for it, just watch this ice cube.
See. It’s melting.
Except… this isn’t always the case.
Wet ice…
uh, ordinary ice - frozen water, will actually sublimate in certain conditions.
If the ambient temperature surrounding some mass of ice remains below the freezing point of water,
ice will slowly sublimate and transition directly to the vaporous form.
This is probably not a perfectly scientifically correct way to explain it, but it’s similar to how liquid water will evaporate slowly and disappear
even at cool room temperatures.
Solid water actually does the same thing - and you’ve seen the effects of this yourself.
Freezer burn, where food stored in the freezer for a long time develops dry spots, is the result of sublimation.
The moisture in that cut of meat or whatever just… sublimated away.
And if you’ve got a bin of ice in the freezer and noticed that over time the ice cubes seem to shrink, that’s also sublimation in action.
You probably noticed, though, that the process is very slow.
It can be sped up, which if you live in cold parts of the world like I do and you drive a car,
you might have actually noticed.
Drive at high speed on a very cold day, and over time little bits of ice stuck to the windshield end up just… shrinking until they disappear,
and that’s sublimation happening - helped along by the huge volume of air which keeps flying past that ice as you drive.
But there’s a way to make it happen even faster than that -
expose ice to a vacuum.
Which brings us back to the freeze dryer.
This thing may look like a cross between a tiny washing machine and a piece of lab equipment but it’s not just looks.
The huge rubber ring on the front of this machine engages with the plexiglass door to form an airtight seal, and that door is very thick.
In fact it’s so thick that it is strong enough to withstand the roughly 1,500 pounds (or 680 kilograms) of force the atmosphere is gonna exert on it
when this here vacuum pump sucks all the air out of the chamber.
Because all this thing is is a vacuum chamber.
But it’s also a freezer.
If we look inside, we’ll find that a compressor and fan-forced condenser live in the bottom of the machine,
and this arrangement of parts is a very typical setup for small, self-contained refrigeration units you might find in a commercial kitchen.
But the evaporator - the part of a refrigeration circuit that gets cold - is integrated into the walls of the vacuum chamber.
Now, that could be seen as just a practical way to make a freezer -
if we ignore the whole “it’s also a vacuum chamber” part, this might as well be a weird take on a chest freezer.
It’s just on its side and a cylinder rather than a box.
But specifically for freeze drying, it has a practical purpose, too, which I’ll explain later on.
The basic process this machine uses to freeze dry things begins simply by freezing whatever you want to freeze dry.
When you start a cycle using its touch-screen interface, it turns on the condensing unit and begins cooling the chamber.
The actual stuff you intend to freeze dry has to be placed on these trays
which are sized just right to fit within the rack structure sitting in the middle of the chamber.
That rack structure is more than meets the eye but hold that thought for now.
You can choose to let the machine itself freeze the items on the tray, though that takes it quite a while.
In my experience something like 6 hours.
So it’s generally better to pre-freeze everything in an ordinary freezer first.
That speeds up the freeze drying process.
It still takes a lot of time to freeze everything and, uh,
it's kinda awkward to fit these in some freezers but generally it's better to do that.
The machine has a temperature sensor attached to that rack structure so it can determine the temperature in the chamber and,
to some extent, the contents in the trays.
Being made of thermally-conductive aluminum and also being in physical contact with these trays,
that sensor’s reading will be influenced by the temperature of the food.
And once it has reached the target freezing temperature, the machine starts a timer.
Both the target temperature and that timer’s length are customizable,
but currently I have the machine set to a zero Fahrenheit target (that’s -18 celsius, typical freezer temperature)
and the extra freeze timer is set for 90 minutes.
Once those 90 minutes are up, all of the moisture in whatever you’re trying to freeze dry will have frozen solid.
And the machine’s next step is to switch on the external vacuum pump by energizing the power outlet on the back of the machine.
This vacuum pump is quite a beast and can evacuate the air in the chamber very quickly.
Generally within a minute the pressure drops below 2,500 millitorr which is about 0.05 psi.
And for context, the atmosphere is 14.7 psi at sea level.
From here on out, the machine will keep the vacuum pump running continuously and it will keep the compressor running, too.
And now, the frozen water in all of the food begins to sublimate.
Except… remember that whole thing about how sublimation is a really slow process?
Well, it is.
The vacuum conditions inside the chamber will speed it up but it’s still gonna take forever if all we do is let the machine sit.
So - here’s where that strange rack situation comes into play.
The racks are not just supporting the trays, they also contain heating pads.
Bonded to the underside of each shelf (including the top piece) is a roughly 150W heating pad.
And, once the machine has reached a target pressure, it energizes those pads to heat the food in the chamber.
Now this might seem counterproductive - we just froze everything, why would we heat it back up?
Well, under a vacuum frozen water behaves like dry ice does in our atmosphere.
It doesn’t melt, and so we can actually warm up the food
and that added energy means the water molecules in that food are vibrating more vigorously which speeds up sublimation.
The machine switches those heating pads on and off to maintain the tray temperature at roughly 130 degrees Fahrenheit, or about 55 Celsius.
It feels really weird that doing that doesn’t melt the water in the food, but it doesn’t!
Here’s a timelapse of the machine freeze drying ice and you’ll notice that it’s not melting,
it’s just shrinking and disappearing,
leaving just a trace of dust - that dust being the minerals which were dissolved in the water - behind.
And now it’s time to touch on something I said earlier.
The compressor runs through the entire process,
which means the whole freezer part of it is still working to cool the walls of the chamber
despite the fact that we’re heating the food and there’s effectively no air in there.
What’s going on with that?
Well, for physics reasons which I don’t understand and won’t even try to explain,
the sublimated water vapor which is freed from the food we’re freeze drying is attracted to coldness and will deposit itself on the cold walls of the chamber.
I would have thought the vacuum pump ends up sucking most of that water out but that is apparently not how it works -
most of it just redeposits on the cold walls and so you get quite a lot of ice buildup as the cycle continues.
Aside from the bit of frost that formed at the beginning of the cycle,
all that ice used to be the water inside the food that we’re freeze-drying.
Here’s a fun fact, while those heaters do speed this process up,
it still takes forever!
This machine has typically spent at least 16 hours in the “drying” step of the process before it determines that it’s done.
It is not fast.
However, once its cycle is complete the machine will move on to extra dry time -
another step you can change the length of, if you like, and you might need to as I’ll explain later.
Uh, but once that timer is done… well it’s done.
The machine very faintly beeps at you to kind of get your attention but all it does is turn off the heaters and the vacuum pump.
The refrigeration circuit will continue to run until you acknowledge that it’s done -
and I believe that’s just to make sure none of the ice which forms on the walls melts and gets on your freeze-dried stuff.
Once you decide whether you want the machine to defrost for you or not (I’ll explain that later) it shuts down,
and it’s up to you to open this drain valve and let air back into the chamber.
[hissing] Once the pressure is equalized, you can open the door and remove the product.
The end result of this process is food which has everything it used to have in there except water.
All the water is gone, but the proteins, starches, sugars, flavor compounds, everything else is still there and relatively untouched.
Most foods end up shrinking slightly, and some foods really do not survive the process all that well,
but for the most part you end up with strange results.
The food (this used to be watermelon) becomes almost weightless, and the texture is radically different.
But it’s still the same food, and if you eat some you’ll discover that it tastes exactly like you’d expect but the mouthfeel is radically altered.
And in many cases, it’s so wrong that the food is quite unappetizing.
But.
That food is now shelf-stable for up to 25 years.
It takes special packaging considerations to attain that extreme longevity -
mainly you need completely airtight packaging with an oxygen absorbing packet thrown in to make sure it doesn’t oxidize, so do not take that as gospel.
And at the risk of getting ahead of myself,
I think this process is a little too variable to actually guarantee that the end result will be safe for anywhere near that long.
But food preservation is not why I got this machine.
I just wanted to play around with a freeze dryer and see what sorts of strange foods I could create with it.
And after literal months of tinkering, I’m afraid that most of what I’ve done is ruin a lot of food.
And in hindsight, that probably shouldn’t be surprising.
Given the mechanism in play here, I think it’s fair to describe the process of freeze drying as accelerated freezer burn taken to completion.
You forget about something in the freezer for a couple years and when you dig it back up, the edges are all crinkly and gross and
that’s literally what this machine does to food.
But all of it, all the way through.
Sometimes the end result is legitimately interesting, and plenty of fruits are strangely delicious once freeze-dried,
like strawberries or pineapple.
I’m surprised how much I like freeze dried cantaloupe [crunch]
It's got a nice crunch.
And freeze dried kiwi fruit was another smash hit - though quite sour.
But most other things you freeze dry end up being rather unpalatable
and so require further work to reconstitute into something less gross if you actually want to eat it.
Take, for example, and I apologize in advance to the vegetarians and vegans watching, meat.
This is freeze-dried sliced ham.
In its current state, it is nearly weightless, has a rough texture, and is quite brittle.
You can snap pieces of it off quite easily.
If you just eat this,
which I have,
it’s disgusting!
The dried meat has a quite off-putting gritty texture and to make matters worse,
it eagerly absorbs the saliva in your mouth and so it’s kinda like you’re eating damp sand.
But what makes it even stranger is that it tastes exactly like ham.
It’s just a viscerally confusing experience and I can’t describe it any other way than just wrong.
This here is a meal from McDonald’s which I threw in the freeze dryer because my morbid curiosity got the better of me.
It’s just your standard two cheeseburger meal but with some McNuggets, too.
And the end result is incredibly weird.
Give this container a good whiff...
and it smells like the inside of a McDonald's.
Get more specific...
and you can make out the smell of the ketchup and onions on the cheeseburger.
But the cheeseburger itself is now a rock-hard disc of misery.
And now, you will get the pleasure of watching my actual reaction to eating some of this food for the first time.
♫ soft jazz ♫
Alright! I lied a little bit, I have already tried the fries and they are…
[loud crunches]
umm…
well, it’s something like a shoestring potato chip
but is does taste like a McDonald’s French fry and it’s a little too brittle.
So, not great.
But I haven’t tried anything else.
Let’s see what a freeze dried McNugget is -
oh that’s unpleasant.
Uhoookay.
[cronch]
Augh.
[confused crunching]
Ope, there it is!
It took a while for the flavor to come through.
It’s a McNugget!
But it’s, like, powdery.
Not great.
Um, and let’s just…
I don’t know how I’m gonna do this.
I don’t really even want to do this.
[extremely uncomfortable cronching]
[more confused crunching]
[confusion intensifies]
I mean it tastes like a McDonald’s cheeseburger!
It really does, but it’s…
WRONG!
It is not a good experience.
So what can you do to reconstitute your freeze dried food into something not gross?
Well, the most obvious thing is to add water but depending on how you do that, it can be weird.
Perhaps the most surprising thing I accidentally discovered had to do with the ham.
I thought the most logical thing to do was of course use a steamer to make some delicious steamed hams.
But when I put the sliced ham into the steamer,
within moments it started getting darker and by the end of just 5 minutes in there,
it had cooked further and become the consistency of jerky.
It was also pretty tasty, I won’t lie, and so I guess I discovered a really odd roundabout way of making jerky from store-bought ham.
But to get the ham turned back into the regular ham it used to be,
well simply soaking it in water for a while kind of worked.
But it got unfortunately soggy in the process.
Like, I imagine if I had left the not-freeze-dried ham in a bowl of water for a half-hour, it would have been a similar result.
I have yet to test this, but I do want to try getting one of those cool mist humidifiers
and leaving the freeze dried product in the stream of mist for a while to see if that might be more pleasant.
I will almost certainly be doing more stuff related to this on Connextras - so be sure to subscribe to that channel if you haven’t already.
Another thing I haven’t yet tried steaming is a steamed ham -
but I do have this freeze dried steamed ham handy so let’s do it!
(It’s an Albany expression.)
Okay let’s steam a steamed ham.
I got out my simmerstat box.
I bet you didn’t think this was gonna come out again but no!
I’m using it right now.
And, I’m turning the heat down to about medium because I want to leave this at a pretty low heat.
I hopefully don’t want to cook it any further like what happened with the ham.
I’m putting in the one that I already took a bite out of.
And we’ll throw in one of the nuggets, too.
How long should I leave it in there for?
No idea! But I’m gonna try ten minutes.
So… tick tick tick tick.
It’s been ten minutes!
Except I threw in some fries, I forgot about that.
I’ll give them a little more time.
Ooh I drip - agh!
I dripped some water on the McNugget. Let me just, uh…
okay that does not bode well.
It’s still... stiff.
It’s still stiff, but....
Oh. Oh no it’s not… it’s not good. And it has cooked further.
Ooh boy.
I mean I think it’s better than it was but, um, it has cooked further.
I’ll turn that off.
I’ll grab one of these fries.
Oh that’s awful.
I now have that set to low so this should barely simmer at all, um and we’ll see if that makes a difference.
Okay there’s 10 minutes of steaming at very low.
I did it again, why did I do that?
I’m just making a mess over here. Okay!
Um…
hmm.
Nope, this is still pretty dry.
So, uh, it hasn’t cooked further so maybe if I let this go for like an hour it would turn into…
or turn back into what I expect out of a chicken McNugget.
Which is not much, to be clear!
But, um, steaming apparently does not work.
Hooray!
There are some foods which can be freeze dried and then un-freeze-dried pretty easily.
Something that I found actually quite enjoyable was freeze drying eggs.
This 1 quart Mason jar has 3 dozen eggs in it,
and I made it by using two freeze dryer trays, cracking 18 eggs into each one,
and then I poked each yolk with a fork to make sure the membrane had broken.
Don’t know if that was really necessary, but I figured it wouldn't hurt.
Then I carefully put the eggy trays in my freezer.
I bought these lids from the manufacturer specifically for making prep easier -
it allows you to stack the trays in your freezer and if for some reason you end up thinking a freezer dryer is a good idea,
I would say this is a required accessory.
But anyway, after spending the night in my freezer, I put the trays in the freeze dryer and ran a cycle.
The next day,
because may I remind you this process takes an entire day,
the machine was done.
And the end result is a much lighter tray filled with nothing but solids of egg.
Using a fork you can scoop these up from the tray and stick ‘em into a food processor,
and with a little bit of food processing you end up with a very fine powder.
It’s quite compressible, so I was able to shove all the eggs into this single jar.
And to turn them back into regular eggs - just add water.
I never bothered figuring out what exactly the proper ratio of powdered freeze dried egg to water is, I’ve just been eyeballing it,
but it quite easily turns back into liquified eggs and with just a bit of stirring.
And they cook up just like eggs do.
I scrambled some reconstituted eggs and you would have no idea that they were ever freeze dried other than the fact that they were a perfectly uniform yellow
thanks to how thoroughly scrambled they become from the food processor.
Which, fun fact, the French call it a robot culinaire.
How delightful.
Another actually-kinda-useful-for-food-preservation-thing
is this.
This used to be a half gallon of whole milk, but now it’s powdered milk!
This was made using the exact same process as the eggs, however it’s harder to turn this back into liquid milk.
I’m pretty certain that’s because this is whole milk and much of these solids are milkfat which doesn’t really like mixing with water.
But I wanted to try this specifically because powdered whole milk is a surprisingly hard product to find in my area,
and I don’t normally keep milk in the house because it spoils too quickly for how I use it.
Though perhaps the difficulty in getting this to dissolve in water explains why nonfat powdered milk is more common.
Anyway, it will turn back into milk when mixed with water it just takes quite a lot of mixing and,
since it’s milk, mechanical aids can end up frothing it so… it’s tough.
Speaking of freeze drying liquids, though, another thing I did was freeze dry some brewed coffee.
Instant coffee is really just dehydrated coffee, but most instant coffee is awful.
So, since I have this high-tech anything dehydrator, I figured I’d make my own instant coffee - but with a twist.
I froze the coffee as I prepare it with cream and sugar,
so the end result should be truly instant coffee exactly how I like it.
The process was basically the same for eggs and milk,
though the end result out of the freeze drier is truly almost weightless and if it weren’t for the sugar I’d be afraid of drafts in the room.
But you just load it into a food processor and turn it into a powder.
This is the result which I haven’t tried yet - let’s do that now!
Okay this will not be scientific.
I just used the scale here and tared it with this empty mason jar which then suggests there’s 43 grams of coffee powder in here.
I’m not 100% confident that this is four or two mugs. I don’t remember. I think it’s only two.
Because of the sugar in here, I’d be really shocked if I only had 10 grams of sugar and milk fat.
So I’m gonna put half of this in that mug, we’ll see what happens.
I’m not bothering to wait until this gets to a boil.
[stirring]
So it’s dissolving pretty well,
it hasn’t completely dissolved perfectly but this does (other than the froth) look very much like how I brew my coffee and, uh,
it doens’t have that acrid smell that most instant coffee really does for me
so let me give it a taste.
Be mindful of the spoon.
This is very good!
This is effectively how I take my coffee in the morning.
I’m gonna call that a success!
Yeah it’s got - for whatever reason the froth that’s forming on here…
it almost - it almost has a whipped hot chocolate consistency on the top but it’s very good.
Am I going to actually make a bunch of this for future use?
No.
But now let’s change gears.
The main reason I bought this thing, aside from making a video,
was to try freeze drying whatever seemed like it might be fun to freeze dry.
But I learned pretty quickly that a lot of stuff just… doesn’t really work.
I knew some of that going into this - I didn’t just buy a freeze dryer,
I did some research into what can and cannot be freeze dried,
so I knew that things with very little moisture content and high fat content just don’t work.
Chocolate, for instance, just ends up melting once the heaters turn on.
Same goes for butter.
But there were also a lot more duds than I figured would be the case.
In fact it’s been mostly duds.
The very first round of freeze drying I did included all sorts of stuff, some of which I just thought would be funny.
For instance, I wanted to freeze dry a Twinkie just because that idea was hilarious on its face.
Sadly I never got around to making freeze dried refried beans.
But anyway, much of that first batch just didn’t actually do anything or was completely ruined.
The Twinkies just became rock hard and impossible to eat.
The cream filling of the Oreos melted and the cookies just turned stale.
Little Debbie oatmeal creme pies had the filling become a powder
and the oatmeal cookies parts turned into the consistency of a cracker crossed with an old ginger snap.
None of that was any good so anything close to a pastry is apparently never going to come out of a freeze dryer in a good way.
That round also included various fruits:
canned pineapple and peaches in addition to a fruit cocktail were done mainly because I already had some on hand and I was lazy,
but I also bought some cut melon and prepped that for the freeze dryer.
And I learned some interesting lessons rhere -
the peaches freeze dried perfectly.
The pineapple mostly did, but over time it became clear there was still some moisture left in it.
And the melon - well it seemed like maybe it was dry, but after a few days in a mason jar well it became clear it was rotting.
The smell was awful.
That was on me, though, the instructions for the freeze dryer make it pretty clear that you don’t want any product over the tops of the trays
and that melon was very much over the tops of the trays.
It was just too big.
Which leads me to my next little lesson.
Dealing with these trays is just kind of annoying,
and freeze drying liquid products is just… not really fun.
The easiest way to do it is to put the empty trays in the freeze dryer then pull them out just enough so you can fill them in-place,
and then slowly push them back in and start the cycle.
And actually - I do have to call out a really clever design feature here.
You’ll notice that the machine is leaning back somewhat -
that’s to allow water in the vacuum chamber to drain when it defrosts at the end of the cycle.
But the racks for the trays are leaning in the opposite direction to perfectly cancel that out so the actual trays remain level.
That’s really good thinking.
Still, dealing with liquids is irritating and means you’re asking the freeze dryer to do the initial freeze which makes the already very long cycle even longer.
So I thought I’d be clever and order some ice cube trays with silicone bottoms and make ice cubes out of whatever liquids I wanted to freeze dry.
So I made ice cubes of egg, milk, and coffee.
This was a mistake!
Probably through some combination of being too tall and not being in solid physical contact with the trays,
once the machine had finished it turned out that the center core of every ice cube still had ice in it.
So the eggs and milk?
Very ruined, definitely not safe to eat.
And the coffee?
Well I guess I could have made coffee with it but I ended up just sending it down the drain.
Honestly that was a real bummer, I really hoped this would be easier.
But, sure enough, liquid product in direct contact with the trays is what you have to do.
And lessons just kept on happening.
During one freeze drying session where I tried such things as black olives
(weird but okay),
dill pickles
(not good),
carrots
(surprisingly disgusting),
yogurt
(more weird than anything else),
balls of seasoned and cooked rice
(disappointing)
and other stuff I’m sure I’ve forgotten I had some lemon and lime slices in there.
Those came out perfectly and aside from the pucker factor made for an interesting little treat.
So later on, I was doing some other fruits and stuff and decided to put in both some sliced tangerines and mandarin oranges.
And for some reason neither of those actually dried to completion.
Everything else in there came out fine, but the oranges did not.
They had a good deal of their moisture removed,
but after storing them in a Ziploc bag, by the next day that bag had condensation on the insides and the fruit had turned into mush.
I can only assume the sugar content of this is just too high or something.
And remember how that first run of freeze drying had a can of fruit cocktail in there?
The grapes in that fruit cocktail ended up being really interesting, so I went out to the store and got some fresh grapes to try.
I had assumed the skin of the grape might be a problem so I poked each and every one with a knife before freeze drying
(I had both seedless green and red grapes in there)
and… well they barely dried at all.
There was some unpleasant oozing coming out the holes I made in the skin the whole time and by the time the cycle had ended…
they were still... mostly grapes.
So then I decided to cut the grapes in half and try again.
Cutting grapes in half, it turns out, is really annoying but I figured that would work.
And I think it did? But, and here comes the bad news,
the end result was really really gross.
Like, I don’t understand how they took on the flavors they did.
And the grapes themselves were fine - I had some while prepping them, because of course I did, and they were delicious.
But out of the freeze dryer they were not!
But rather than dwell on the bad stuff,
now let’s talk about some of the better things I was able to do with the freeze dryer.
The most surprisingly good thing?
Onions.
Just raw onions.
They leave the freeze drying process with the texture of a potato chip, so with a little salt and oil
[cronch]
they might as well be all-natural Funyuns.
I tried this only because I once bought these onion chips from Trader Joe’s and the ingredients were just onions, bran oil, and salt
and the bag was a bit cagey about the “process” used to create them.
So I tried freeze drying an onion and I’m reasonably sure that was the process.
They were very similar to the product from TJ’s.
I did do a run where I roasted some in the oven for a bit before freeze drying them and that didn’t seem to make much of a difference as far as the flavor goes.
But I suppose one thing I do need to try now is caramelizing a bunch of onions and then freeze drying them.
Mmm…
I also cryodessicated various peppers: two bell, one jalapeno.
These ended up with a similarly chip-like consistency to the onions, though personally I found them to be less enjoyable.
And the jalapeno - maybe I just lucked out and got a particularly spicy one,
but that was an intense vegetable chip.
And yes, I am a Midwesterner, and I look like this.
I know that. But normally I like jalapenos on stuff and find them fairly mild, so
either freeze drying really accentuates the capsaicin or I just got quite a banger from the store.
Many candies also do some interesting things in the freeze dryer.
Turns out skittles - they pop like popcorn!
They split in half and the innards puff up, and the end result?
[a nice crunch]
It's got a nice crunch.
Gummy candies tend to really explode in size -
these here were gummy bears,
these were gummy worms,
and these were ♫ gummmm-eeee sharks doot do do do do -
we’ll never speak of that again.
These are less fun to eat - I would describe the texture as almost like a candied glass.
Dentists would definitely have some thoughts about this.
Interestingly, though, not all gummies do this.
I had some peach rings which I ran through here and their texture was altered slightly but they didn’t grow in size.
And I also ran some spice drops through the freeze dryer and they were completely unaffected!
What’s up with that? No idea.
And then of course there’s Astronaut Ice Cream!
I don’t have to go to the science museum gift shop anymore, I can make it at home!
That was totally worth buying this thing.
Anyway freeze drying ice cream is actually somewhat difficult to get right.
The first time I tried it I just put in a few store-bought ice cream sandwiches but I put them in too early.
The chamber wasn’t cold enough and while they didn’t look like they were melting at all,
and perhaps they weren’t initially,
the inside of them liquefied at some point and it was unpleasant.
I tried some of the same sandwiches later, making sure to let the chamber get well below freezing first,
and they came out exactly as you would expect - actually quite a lot better than the stuff you can buy in a store.
And later I tried just some smatterings of ice cream that I had smashed onto one of the trays which I let stay in the freezer for several hours and it came out fine -
though the cherry filling in this did expand a little bit like the candies.
The next question is - do I actually like astronaut ice cream?
And the answer is…
not really.
I mean it’s kinda fun but it wears off pretty quickly.
So now, let’s get back to the whole utilitarian aspect of things.
A big selling point of these very expensive and slow machines is that they can preserve a wide variety of food effectively forever.
And that’s essentially true!
But I want to pick that apart because if you step back and look a little holistically at this situation…
I simply cannot find owning one of these to be rational.
Maybe that sounds blunt, but if this looks like a good idea to you…
our mental frameworks are just completely misaligned when it comes to the value of time, money, and effort.
And also,
at the risk of getting a little deep,
you might be worrying a little too much about the apocalypse.
Why do I say that?
Firstly, just getting and using this thing is a commitment!
It was shipped via freight on a pallet and I bought this workbench specifically for it.
No it’s not huge but it’s very heavy - there’s a reason it’s not here on my desk -
and you’re not going to want this in your kitchen.
Remember how way back at the start I said its condensing unit was the same sort of thing you find in small commercial refrigerators?
Yeah, well, this thing is loud.
[compressor startup, followed by building drone]
The droning of the condenser fan matches the most annoying vending machine at the bus stop
and it will run the whole time.
And then the vacuum pump starts up and just adds to the racket.
[rattly, gurgly noises]
The vacuum pump is actually a lot quieter than I expected, so that’s good, but it’s still more noise and it will not stop for at least 12 hours.
[audio contrast between droning condenser and rattly vacuum pump]
You’re gonna want this thing in a garage or a basement, and unless you’ve got one of those basement kitchens,
that’s going to be annoying when it comes to the prep required to actually use the freeze dryer.
Nextly, this process is extremely energy-intensive.
Over a cycle the machine uses about 16 kilowatt hours.
It varies a bit depending on what exactly you’re freeze drying but it’s been pretty close to 16 every run that I’ve tested.
That’s about $2 worth of electricity for every cycle,
and that same quantity of energy will power my car for three rounds trips of my commute.
I do have a somewhat short commute (it’s about 20 miles round trip) but quite literally if I used this thing every day
it would be using three times as much energy as my car does (during the summer months, anyway)
and it would cost about $60 a month.
Yikes!
And if you’d like me to make a different comparison,
a typical 7 cubic foot chest freezer needs just about 650 watt-hours per day,
meaning one freeze dry cycle uses as much energy as a freezer does over 25 days.
And to really drive this point home, this is the second-smallest unit Harvest Right sells
and the larger machines have a NEMA 5-20 plug on them.
That's the one with the sideways blade which will only fit into outlets like this on a 20 amp circuit.
These things just need a stupid amount of power to run all those heaters in addition to the compressor and vacuum pump.
Oh, and speaking of the vacuum pump, that thing needs maintenance!
It has oil in it, and every 20 cycles the oil needs to be drained and filtered.
Luckily they included an oil filtration system with the freeze dryer.
And what is that, you ask?
It’s a Brita pitcher.
It’s literally an off-brand Brita pitcher.
Honestly this made me laugh out loud when I saw it.
The machine will prompt you to do that maintenance when required,
and this company does sell an oil-free vacuum pump which does not need this maintenance
but that’s a $1,500 upcharge.
Yeah.
And what about the time part?
In case you haven’t noticed, you can’t actually freeze dry all that much food at one time.
This company’s website claims the machine can process 10 to 15 pounds of fresh food per batch.
Which, to be honest, I don’t doubt at all!
But you’re only gonna be able to do one batch per day
and while the machine itself is mostly set-and-forget, the prep work absolutely is not.
It’s a chore.
And since the trays are gonna be in the machine for the next 16 to 24 hours,
you can’t prep the next batch unless you buy a second set of trays.
Which I did - because even just playing with this thing for the purpose of this video was tedious enough to make a second set of trays worth having.
And by the way, you can’t start your next batch for two hours because you need to let the machine run its tray heaters to defrost the insides and get rid of all that ice.
It’s a lot of work!
But then! You’re not even done when the machine is done!
You have to package everything you just freeze dried if you actually want it to stay preserved,
and that’s more work and time you’re gonna have to spend plus more money on whatever sort of packaging solution you want to go with.
And of course, the company will happily sell you packaging supplies from mylar bags to oxygen absorbing packets.
Though to be honest their pricing is quite reasonable so I’m not actually mad about that.
I’m just saying if you actually intend to preserve lots of food with one of these, understand what you’re signing yourself up for!
It’s a lot of work and a huge time commitment.
And that’s before you even consider where you’re going to put all this food!
I do not have the pantry space for the end result of a year’s worth of freeze drying.
And to drive the absurdity point home, let’s just compare this freeze dryer with a conventional freezer.
It’s not a perfect comparison and I know that -
for one thing not all food is suitable for storage in a freezer and while they can technically store food indefinitely freezer burn does damage stuff with time.
But for the sake of argument let’s just say you had $2,800 to spend on food preservation stuff.
You could buy this.
Or, well, remember that basic 7 cubic foot chest freezer I mentioned earlier?
Those cost about $200.
They’re commodity items and you can get them for about that price from many different retailers and that size usually has the smallest dollar cost per cubic foot.
So let’s just say we’ll get, eh, 10 of those.
If you’re thinking you’re gonna be freeze drying food all year you definitely have some sort of bunker which can fit 10 chest freezers
so let’s not dwell too much on where you’re gonna put all them.
Plus you could build some shelves and stack them.
Probably.
Actually you could definitely just stack a few on top of each other if you know for sure you don’t need to get to anything in the bottom ones until 2028.
Anyway, congratulations, now you’ve got 70 cubic feet of frozen food storage.
But wait! You say.
Freezers need electricity to function, so what if the power goes out?
Well, lucky for you, you still have $800 left over to buy yourself a portable generator.
You can run to your local harbor freight and pick up one of these bad boys,
and you’ll still have some pocket money left for a gas can, a few gallons of gas, extension cords and power strips.
And it will absolutely take care of all those chest freezers - those things only use about 80 watts when they’re running,
so as long as they don’t all start at the exact same time and overwhelm the generator with their required starting current,
you’re gonna have plenty of power available for all of them plus your kitchen fridge and some lights and the TV and whatever else.
I have lived through extended power outages off a smaller generator than this so I do actually know what I’m talking about, here.
And if I were a gambling man, I think it’s a pretty solid bet to assume
that anyone actually looking at one of these freeze dryers to use unironically as a means to build up long-term food storage
already has a generator.
Again, I know the comparison to a freezer is not entirely perfect but another thing to consider about them is that...
you just put stuff in them and that’s it.
You’re done.
If you’re, like, doing your own butchering and packaging then sure, there is more than zero prep and packaging cost
but I can all but guarantee you will be spending much, much less timestocking 10 freezers,
especially since you don’t need to thinly slice everything to make sure it doesn’t stick up above the edges of these trays.
Now I don’t want to sound too negative -
this freeze dryer is truly a fine product which I would recommend
were it not for the rather huge fact that the math just isn’t mathing.
If your brain allows you to think it does, by all means have at it.
But if you’ve watched this video and still think a freeze dryer is something you need in your life
our brains work real differnt.
I think that if somebody were to make a really small freeze dryer which only cost a few hundred bucks
it would be easy for me to say “sure, play around with a freeze dryer, some foods are fun to freeze dry”
but the market right now is basically just variations on this machine and the pricing is fairly uniform.
Which makes sense, this really is lab equipment and not really a kitchen appliance.
And honestly, that’s really what makes me so uncomfortable about this whole thing.
They’re being sold now as if they are the next air fryer and, like, no.
You don’t need this.
It’s going to be a massive commitment and unless you’ve got a lot of disposable income and time, I truly think this is not a smart purchase.
Having said that, the last things I’ll touch on before I wrap this video up are the little annoyances with this particular machine and the process more generally.
For any freeze dryer, the seal of the vacuum chamber door is very important.
It doesn’t need to be exactly perfect - once the vacuum pump kicks on the atmosphere does a fine job of holding that door in place.
But the seal needs to be good enough for the vacuum pump to overcome whatever air might leak past when it starts up,
and on this machine, the door latch and hinge design is not that great for making sure the seal stays flat.
It has three attachment points which effectively means it’s a tripod,
but should you need to make any adjustment you’ll soon discover that only two of them are adjustable.
The latch isn’t adjustable at all, at least not without bending anything, and it doesn’t really form a very tight seal.
And while you can adjust the hinges,
they have a design which allows the door to move inward somewhat - which makes sense, that’s going to happen when the vacuum pump switches on.
But it makes adjusting them a nightmare.
Out of the box, this thing didn’t need any adjustment.
But on that first cycle, it was fairly warm out in the warehouse and I had not pre-frozen anything,
so it ran for more than 6 hours just freezing the food I had put inside.
In that time, combined with the warm room, ice was beginning to form behind the rubber seal outside of the vacuum chamber
which started pushing the seal forward and making the contact points with the door uneven.
So I started fiddling with the hinges and that’s when I discovered how nightmarish this adjustment is.
I truthfully don’t know what’s the bigger issue here - the fact that some ice forms on the outside the vacuum chamber and deforms the seal, or the weird hinges.
I have found that always pre-freezing the trays mostly eliminates the icing problem -
if they’re at freezer temps when you load them in, the machine only spends about 2 hours before it switches on the vacuum pump.
And once it starts the vacuum pump, so long as the seal is good, the hinges and latch don’t even matter anymore.
But I’m also shoving a piece of cardboard under the latch every time I start it to make sure the seal is tight
and I really don’t feel like I should have to do that with such an expensive machine.
The other problem is a little more serious.
I cannot for the life of me figure out how it determines that the cycle is complete.
Once it moves to the drying step, the most useless progress bar I have ever encountered shows up on the screen.
That bar will move in completely unpredictable ways.
Sometimes it only fills up about a third of the way and then the machine decides “I’m done!” and now you’re in extra dry time.
And other times it seems to fill up pretty normally, but then get stuck at the end.
Like a Windows machine.
I had presumed that the machine is probably monitoring the vacuum pressure as it turns the heaters on and off.
My intuition was that each time the heaters switch on, the vacuum pressure goes up slightly because more water is sublimating,
so it’s just looking for those little spikes to stop happening because when all the water’s gone, that won’t happen any more.
But after several time lapse sessions with the gopros, it’s clear it’s not doing that.
But what it is doing ain’t any clearer.
On this batch, it was barely into the fifth hour of the whole cycle when it suddenly decided “Extra Dry Time! I’m done!”
and, uh, when I saw that I literally said to it “no you are not.”
Luckily you’re able to just bump up the extra dry time, which I did until it got to like 17 hours because I knew there was no stinking way that batch,
which had a lot of watermelon in there, was anywhere near complete.
This was also the batch with the tangerines and mandarins and you could tell just by looking at them that they were still bubbling.
And the fact that the vacuum gauge was reading in the 400s when it thought it was done when on other cycles it was in the 100s when that happened
means I have absolutely no idea what algorithm in there is running.
I mean, on this cycle I was literally just freeze drying four trays of ice with one tray of Jell-O,
and all the ice had completely disappeared and yet it still thought it’s not done.
I just have no idea what it’s looking for.
Ah, however - I must actually give it a little credit there.
I ended this session manually because I was sick and tired of waiting for it and I wanted to go home,
and when I removed the trays I ate a few of the Jell-O pieces.
Freeze dried strawberry Jell-O has a crunch and taste which is shockingly similar to the Crunchberries in Cap’n Crunch cereal,
but sadly after a few seconds the gelatin flavor comes through and ruins it.
But anyway, some of those Jell-O pieces still had a bit of ice in the center.
So the machine was actually right - the process was not complete.
But it also revealed how inconsistent the process itself is.
All of the ice cubes had completely disappeared, but the freeze-dried Jell-O apparently functioned something like aerogel
and made an insulating layer which prevented the heaters from actually heating the center of each piece.
I chomped on one right as I took it out and the center was still ice cold despite the tray itself being hot.
I find this really interesting but also a little concerning when it comes to the actual safety of the food you freeze dry.
In fact, that whole part of this process just gives me the heebie jeebies.
I would make sure to sample everything which I had run through the freeze dryer to make sure it was actually thoroughly dry
before I moved on to packaging it for long-term storage.
I just can’t trust the machine’s judgment.
The manufacturer clearly wants this to be a one-button set-and-forget experience - the documentation this came with is really light on details
and I would call this a quick start guide, not an owner’s manual.
And all it says is the machine “is measuring the removal and moisture and knows when the process is complete.”
But I’m pretty sure a one-button experience just isn’t a reasonable expectation for this sort of machine.
And they know that.
They, too, suggest checking everything to be sure it’s dry and,
for what it’s worth, you are able to put the food back in the machine and resume the process if it’s not done.
There is a USB input on the side so presumably the software could be updated;
this is apparently running version 5.4, and I will leave open the possibility that something is actually wrong with thisparticular unit.
But I have a theory as to what’s going on and I think it’s an unsolvable problem.
Both the manual and demonstrations of this product on their website imply that mixing products in here is fine to do.
But… I’m a little skeptical of that.
I have not removed the rack structure because it would involve messing with seal which I really don’t want to do,
so I can’t say this with certainty but I believe thee two rivets here are holding the temperature sensor for the tray rack.
And that means it’s influenced by what is on those trays and which order you loaded them in.
If you put trays with more stuff and/or more wet stuff on them farther from that sensor, it may think it’s done early because a lighter, drier tray was closer to it.
I definitely know from all my testing that if the overall mass of the food on each tray varies a lot from tray to tray, the machine is more likely to be confused.
It may end too early or it may go on a lot longer than it needs to.
And what’s most interesting about that, to me, is that this isn’t explained at all in the machine’s owners manual.
But truly, I don’t want to sound too hard on this product or this company.
I actually quite like it, and so long as you’re aware of the fact that it may end the cycle too early and you’re on the lookout for that, it’s truly a fine machine.
And while it was hideously expensive, for what it is I think its price is actually reasonable.
What I don't think is reasonable, though, at least in my opinion,
is ordinary people having one of these in their home.
It’s either a very expensive toy which you’ll probably get sick of using before too long or,
if you seriously think this is worth having for nearly indefinite food storage,
understand the many commitments you will be making before you pull the trigger.
I’ll wrap up now, but let me reiterate the commitment thing.
You are signing up for hours and hours of tedious work to use this thing as an actual food storage tool.
And, at the risk of getting a little spicy,
if your spouse is trying to convince you this is a great purchase…
make sure they’re willing to help put in the work.
I'm already quite confident that I would resent a partner who bought this for me and presumed I would have a fun time using it every day.
But that’s just me.
Thanks for watching!
♫ cryodesiccatedly smooth jazz ♫
Unless you’re big into the p(r)epper community, ya might regret.
I said “pepper!”
…of fats and oils can turn some foods rancid.
And then there’s oxygen in our-- oh mck fffh.
And SINCE there’s oxygen in our atmosphere.
Water is wet.
Or does it make things we - are we settled on that? Anyway,
forovplbbbh.
…vibrating more vigorously which speeds up the p pp p pb g p p
[snorts]
And I made it by using two freeze dryer frays…
now we’re galling apart.
[crunch]
Has a nice crunch.
[talking with mouth full] Gummy candies tend to really explode in size.
These … I can’t continue that take, huh?
So... does this make me an anti-influencer?
I mean, it's not like I don't think the thing is cool it's just freaking nuts how they're starting to creep into the mainstream conversation.
I mean... in my opinion.
But it's a very informed opinion.
Anyway, now to freeze dry those refried beans.
And please vote.