Cured egg yolks

"Any chef worth her salt ... knows that transforming inexpensive, readily available ingredients into something special is the key to making memorable dishes. One of the best examples of this practice is the salt-cured egg yolk." Melissa Clark - The Splendid Table

Now this is a truly weird thing that I came across when I was researching muslin. I wonder if one would come across it if you were looking to do something with leftover egg yolks? Not that I am ever likely to have leftover egg yolks because I never make meringue. I just can't. It never works and I don't think I am sufficiently attracted to cured egg yolks to then have a whole lot of egg whites I don't know what to do with. So I am unlikely to ever do this, but it does look to be extremely simple and they all seem to rave about it. So here is the lowdown.

I cannot find anything about the history of this. It sounds sort of ancient Chinese to me, but maybe not. And who would have thought of doing it? I suppose if you are curing other things like fish or pork then maybe you might have thought to do the same to egg yolks. But then why would you have egg yolks? They didn't make meringue back in ancient times. That is a relatively recent thing I believe - maybe 18th century? I've forgotten now though I did discover that when I was doing whisks and also egg whites.

Whoever discovered curing egg yolks, there now seem to be three and a half basic ways of doing it - salt/salt and air drying too, salt and sugar, and sugar. A further refinement is whether you want your eggs soft or hard at the end of it all. Which is really just a matter of time.

Well I came across the sugar version when looking for classy chefs who cure eggs. Nadine Levy Redzepi - wife of the Noma man, has a recipe for what she calls Sugar-Cured Egg Yolk in a Meringue Cloud.

But I don't think it really counts as cured. If you read the recipe you just drop the yolk in a sugar syrup for a bit. This is no days long process. Pretty though. But I do wonder why you would call it 'cured' unless you were trying to jump onto some kind of bandwagon. The meringue cloud is not really meringue either - just stiffly beaten egg whites, though there is crushed meringue underneath.

And whilst we are on celebrity chefs, Yotam Ottolenghi also has a recipe that he calls Marinated peppers with fresh corn polenta and soy-cured egg yolks and this is not really what I would call 'cured' either. You 'cure' the egg yolks for just 2 1/2 hours because you need them soft. More like a marinade really. However he does say:

"The cured egg yolk, which is a cinch to make, adds richness and colour to this meal in a bowl. I urge you to try it in polentas and pastas, even if you’re not going to make this whole dish."

Then just to move even further away from the topic in hand, inspired by Ottolenghi's soy 'curing' I found that there is a Korean dish called barchan which is soy marinated whole hard-boiled eggs I think. And these might, in fact, be more of a thing because one of the recipes I found is from Momofuku. The recipe is reproduced on the Food 52 site from a book by Christina Tosi - so it's sort of third hand, but still ... - trendy. On the left Soy marinated eggs from Bon Appétit and on the right Momofuku's soy sauce eggs of which Christina Tosi says:

"What I like best is that these eggs can be used in a thousand different ways: They are perfect on their own as a snack, or on an English muffin, in pasta, or cut up and mixed into a salad. You can vary the marinade as you like—add sake, scallions, ginger, mirin, garlic, chiles, or rice wine vinegar. What's to stop you?"

soy marinated

momofuku

At least they have the decency not to call them 'cured'.

Back to curing. I also thought to look in my early Christmas present - Salt, Fat, Acid, Heat and particularly the bit about salt. You would think that the author, in such a comprehensive tome, would have covered salt-cured egg yolks. But no - no mention at all. Which makes me think that is not really a thing. As yet. Or has it come and gone?

So - salt-cured egg yolks. Indeed very simple. In the simplest form you simply make a bed of salt, make hollows in it, drop in your yolks, cover completely with more salt and leave to dry in the fridge or cool place. How long you leave them will depend on how hard you want them.

The Practical Self-Reliance website has the 'purest' (and easiest I think) recipe, although it takes a long time. A week for the salt bit and then wrapping in muslin and air-drying for another 7-10 days. Sort of romantic though. This lady also has an explanation for why it's safe and healthy.

"A high salt environment inhibits certain spoiling bacteria, which allows other cultures to dominate. It’s not that salt prevents anything from living in the yolks, it’s just that it slows the growth of some types of bacteria until the others can take over and release lactic acid. It’s the lactic acid that actually preserves the food, and the salt just facilitated the whole thing. Good work lactobacillus!" Ashley Adamant

What she doesn't explain is that the eggs become hard because the salt draws the moisture out of them. And I really don't know if her 'scientific' explanation is correct or not. Sounds plausible.

Such a simple (if tedious) process does of course, lend itself to variations. The most obvious of which is drying in an oven either during the 'curing' process or during the drying one.

"The process is dead simple: Separate yolks, pack in salt and sugar, wait, rinse, dry in the oven, and use. Like a hard cheese, cured yolks can quickly add savory depth and complexity to a wide range of foods—soups, salads, pastas, and even meats."

There are also lots of recipes that have a mix of salt and sugar - a bit like gravlax. I'm not sure what difference this would make as nobody really explained why. Probably it's just a flavour thing. I wonder if you could add other flavourings in the form of herbs and spices?

Then what do you do with them?

"They’ll keep for months, and can be grated on to all sorts as an alternative to bottarga or parmesan. Cured egg yolks are a great addition to carbonara, too, grated on top when the pasta has cooled slightly, so it doesn’t scramble." Tom Hunt

Yes everybody mentioned the carbonara.

Then there's soft-cured egg yolks, which are somewhat different.

"Soft cured egg yolks have a pretty interesting texture, actually. I would describe them as being akin to the inside of a jelly bean. Slightly chewy, rather gooey, but still incredibly unctuous." Jess Pryles

On her eponymous website Jess Pryles explains how to do it - basically a shorter time in the salt and sugar mixture she goes for. And then you do exotic things with them such as spreading on steak adding to a charcuterie selection or spreading on toast before topping with bacon. In other words she seems to think they are particularly good with meat.

Isn't it wonderful what people think of doing with food? I would never have thought of doing this, and, as I said at the beginning of this post, I don't think I ever shall actually do it, but you never know.