I tried 6 experimental techniques to preserve eggs at home from dehydrating to Chinese century eggs

• I tried six experimental ways of making eggs last longer.
• From coating them in miso to salt curing them, I wanted to know the best way to increase the shelf life of eggs at home.
• Each method had its drawbacks but there was one that stood out above the rest.

Following is a transcript of the video.

Charlie Floyd: So, you're in lockdown, you've gone to the supermarket, and maybe you've bought way too many eggs. And you're looking for a way to make them last. I wanted to look at all the different ways you can make your eggs last, from one week all the way up to a year and more if possible.

Are these techniques any good? Do they work at all? And is it worth it? Once you've cooked an egg, you're not going to get much of a lifespan out of it. But with this method, you might just be able to make it last a little bit longer. These eggs are incredibly easy to make and will last for about a week in the fridge.

So, the process for this is really simple and only needs two ingredients: boiled eggs and miso paste. Getting hold of certain things in lockdown has been tough. I grabbed the only miso paste I could, which probably isn't quite right for this. A less sticky white miso might have been easier, as this stuff really stuck to my hands, and the white miso is generally less salty as well, so it might've worked better with the egg.

But either way, I'm gonna completely cover the eggs in the paste. Then once the eggs are covered, I'll put them in the fridge. That's it. I got this recipe from the book "Preserving the Japanese Way," which is really great for all things preservation. The recipe says not to leave the eggs wrapped up for more than four hours. I found that the longer you leave them, the saltier they get. If you're using them as a topping, they're just about OK to leave overnight, but by themselves they get too salty. Overall, though, these were a big success.

They were so easy to make, and the result was a rich, miso-flavored egg that's great on top of ramen or as a snack with a beer. It does use quite a lot of miso, but you can reuse this to coat more eggs.

If you want your eggs to last longer than a week, you're probably gonna need some salt. And salted eggs have been around for quite a long time, especially in Asian cooking. You find salted egg yolks in the middle of moon cakes or on top of a congee. But recently, salted egg yolks have become really trendy, and you'll find recipes for them popping up everywhere. The process is pretty simple.

You surround the egg yolk in salt, drawing out all the moisture and preserving it. Again, you only really need two ingredients for this recipe, salt and eggs. Some recipes I found just used the salt. Some go as far as 50-50 salt to sugar. I landed somewhere in between and added a bit of sugar to take the edge off. I've seen a lot of people add flavorings too, so I threw some mixed herbs and chili in as an experiment, but I can't see the yolk getting a huge amount of flavor from them. So, that's the base.

Then we're gonna make some imprints with an egg and then gently place each yolk into these. Make sure each is completely covered with salt before leaving for a few days in the fridge. After about three days, my yolks had almost completely solidified. They're still fairly sticky at this point. If I was doing this again, I might have left them for longer. But once they're out of the salt, they just need some further drying. It's really nice and warm at the moment, so I just wrapped the yolks in muslin and hung them up in my kitchen. But if you're doing this at home, you can also put them in the oven on a very, very low heat or use a dehydrator to dry them out.

I have put them in the oven when making this ages ago and completely forgot about them. So if you are doing this in the oven, maybe set a timer. And this is the result: a grate-able egg yolk that looks and acts almost like a hard cheese. They don't taste as eggy as you might think and just add an extra bit of depth to whatever you grate them on. I think overall they were pretty fun and easy to make, and I'll definitely be making them again.

To make our egg last even longer, I'm gonna try fermenting it. Now, you can easily just put a boiled egg in some salted water with a starter culture, and it should ferment by itself. But I'm gonna be using old jars of kimchi and sauerkraut that I have lying around, and I'm gonna put the eggs directly into that. Hopefully this will speed up the process and give the egg that sauerkraut taste.

Now, if you don't have anything fermenting and you don't really know what the best option is, making some kimchi at home is actually pretty easy. The only specialty item you need is gochugaru, a dried red chili powder. Everything else is easy to get hold of. And if you've never considered making it, it's surprisingly quick to throw together.

You need Chinese cabbage, ginger, the gochugaru, garlic, and spring onion. I used a white onion because, again, with lockdown, I couldn't get spring onions at short notice. Just mix all these ingredients together in a bowl. You can be completely free with the quantities, as long as you weigh the total. And add three percent of that total weight in salt. Mix together and leave it for an hour or so. I also added some fish sauce, but that's completely optional. And once it's all together, place it in a jar to ferment.

Make sure that the ingredients are all covered by liquid, and leave it for a couple of weeks. I've always got piles of jars of things fermenting away, taking up all the kitchen space. I've got lots of fresh vegetables from the allotment, and inevitably it goes bad if I don't do something with it.

I've got a couple of older jars happily fermenting away. So, really, all I need to do is add the eggs. I made a solution of 2% salt water to top up the ongoing jars and to make sure they would all be completely covered in liquid. And then simply drop the eggs in. After about a week of fermentation, the eggs are ready. How long they last, though, seems to be up for debate. People online claim everything from two weeks up to a very ambitious year long. But they should last a week fermenting and about a month in the fridge.

Fermented eggs might not be for everyone. The taste of the egg and whatever you're fermenting them in is actually really nice, but the egg itself can end up being a little bit fizzy. I've seen a few places saying this, so it's not just mine, clearly. And a fizzy egg is not something that I'd be desperate to make again.

I was looking for something that might last more than a couple of months, so I turned to the good old pickled egg. This one's probably the easiest on the list, and I made it even easier by buying ready-to-use pickling vinegar. You can get this in almost any UK supermarket.

I don't know about the US. But it's extra-strength malt vinegar that's already spiced. You can even just use the jar it comes in. I added a couple of extra cloves and a black cardamom pod for a little bit of extra spice. But you can simply boil the eggs, peel them, and put them in the vinegar. If you've never had a pickled egg before, the result is vinegary, spicy, and perfect as a snack.

If you're looking for an easy way to get a long life out of your eggs, this is probably the easiest and best option. And they should last for about six months in the jar. If pickling is one of the easiest ways to preserve your eggs, this one's probably the most effort.

Chinese century eggs have been around for about 600 years, and when done right, they're black, gelatinous, and, frankly, look quite unappealing. I wanted to see how easy it was to actually make these eggs at home. I didn't really know where to start with the century egg. Looking online, it seems there are a lot of different methods. In the end, I decided to just use pure sodium hydroxide. Now, sodium hydroxide is caustic. It can be harmful to breathe in and can burn your skin. So when using it, you need to wear goggles, a face mask, and gloves.

Getting a face mask at the moment isn't the easiest thing ever, and it turns out I only had two left gloves. I looked around online and found some recipes using similar sodium hydroxide to me and some using drain cleaner, which I really wouldn't recommend. A lot of other information I found online also seemed wrong or really dangerous. Boiling the mixture caused it to violently bubble, almost spilling over the pan.

Putting the mixture into a glass container is dangerous, as sodium hydroxide can actually eat away at the glass. And using an aluminum pan is even more dangerous, as the liquid can react with the aluminum and make a toxic gas. All in all, compared to the other methods, this is looking like it's far from worth doing at home. So once I had the mixture of sodium hydroxide, salt, and tea, I poured it over the eggs and left them to sit for 10 days. 10 days later, the eggs have definitely changed a lot. They're darker, and you can see where the mixture has entered the pores.

After the first 10 days, the eggs were ready to remove from the liquid and wrap up. Traditionally, the eggs were made by being buried in a mixture of wood ash, lime, salt, and clay. So I grabbed some ash from my allotment and bought some modeling clay, which I could use to wrap the eggs up in. Each egg was carefully wrapped up in this clay mixture and left for another 10 days. Now, I do a lot of stupid experiments in the kitchen, but I've never done anything even remotely like this. So, after 20 days, I should have a final result. Batch No. 2. It's the backup batch.

These have been in here for... 11, 12 days now. I mean, I already checked how this one's doing, and it looks far more solid than the last batch. So there's a glimmer of hope here. Perhaps it's a fresher egg. I think that's probably as close as I'm getting. I'm not going to try this weird, semi-jelly egg, so I don't know what it tastes like. But it does smell very strongly of ammonia.

If making a century egg at home doesn't seem like an appealing prospect to you, and I wouldn't be surprised if it doesn't, there's one way to make your eggs last even longer than all the other methods combined, and that's drying them.

Industrially powdered eggs can last five-plus years, but I wouldn't recommend dehydrating your eggs at home and then leaving them in the cupboard for five years. I probably wouldn't recommend dehydrating your eggs at home generally, but this is the way to make them last the longest. The best way to make eggs last is by freeze-drying them. But for that, you unsurprisingly need a freeze-dryer.

These can cost around $1,000. And so I picked up a cheap dehydrator online, which will hopefully do a similar job. I'm just gonna mix the eggs together, pour them out, and then they should be ready to dehydrate. I set the dehydrator to 65 degrees for about six hours. This might have been a little too high, but I wanted to make sure I got every last bit of moisture out of them. So, after it's all dried, I've ended up with a weird crystallized egg. I'm gonna put this through a spice blender, and I should end up with a powdered egg that I can easily store in a cupboard.

So, this worked a lot better than I thought it would, but unless you're preparing for the apocalypse, I don't know why you'd try doing this at home. So, to test how well this works, it's been about a month, and I'm gonna try to rehydrate my eggs and make an omelet. No matter how much I mix the powder, it doesn't really dissolve. So the mixture's still grainy. Maybe I put too much water in to try and get it to dissolve.

It smells like a normal omelet, but these bubbles are very weird. [eggs sizzling] Yeah, I'm not sure I'd recommend this. It looks all right. And smells all right. It's just the texture, I think.

It tastes like an omelet. [roommate laughs]

Roommate: Is the texture all right?

Charlie: Yeah, it's not too bad. Considering. [roommate laughing]