Testing scientists’ 32-minute ‘optimal’ boiled egg

Many people say that “good” art is subjective, and I’d say the same goes for the “perfect” egg. One woman’s deliciously jammy center is another’s way-too-runny nightmare.

And you can order or make eggs in a dizzying array of styles, from over easy to hard-boiled. Of course, any discussion of eggs these days has to start by acknowledging that, yes, they are crazy expensive right now, because of the avian flu knocking out chicken flocks and pinching supply. So when you do eat them, shouldn’t they be just how you like them?

When Italian scientists last week published a paper claiming to have found a novel method for achieving an “optimal” boiled egg, we took note. The researchers claim to have cracked the problem they say has held back egg cookery — namely, that the yolk and whites should be cooked to different temperatures. Their technique, they say, pulls off this feat.

They claim that the results are superior to the two existing methods for achieving a pillowy boiled egg: soft-boiling and sous vide (the latter of which involves the use of an appliance that circulates water and maintains an even temperature, cooking the eggs for an hour or more at a low temperature). The whites, or albumen, of sous vide eggs are often too runny because the proteins don’t firm up at lower temperatures, said Ernesto Di Maio, a scientist at the University of Naples Federico II, who oversaw the project. The shorter cooking times for soft-boiled eggs, on the other hand, do not allow the yolks to reach a high-enough temperature, while the albumen does. “The insides are runny,” said Di Maio, whose research is typically focused on plastic foams and layering structures. “Too liquid.”

The scientists’ method also yields eggs that are higher in polyphenols, antioxidants thought to have health benefits, the paper claims.

To develop it, Di Maio and his colleagues first used computer simulations to determine how the eggs would respond to different temperatures, then set about doing real kitchen tests. The team used about 300 eggs in the process, he said — which fortunately didn’t blow the budget, because he had a friend whose company sells eggs supply him, gratis.

The recipe they ultimately arrived at, which was published in the journal Nature, sounds simple: Eggs are transferred back and forth from a pan of boiling water to a bowl kept at a cooler temperature, which they call periodic cooking. But it only sounds simple until you try it, which I did, first in my own kitchen.

What makes the endeavor tricky is, first, maintaining the temperature of the cooler water bath at 86 degrees. I found that every time I slid in the eggs — which were fresh from the boiling pot — the temperature went up several degrees. I kept a pitcher of cool water nearby that I used to attempt (mostly unsuccessfully) to regulate it. Of course, the temperature in the bowl varied (heat rises!), so I tried stirring it around with my hands or a spoon to keep it more consistent as I moved the thermometer around the bowl to check.

And then there’s the not-so-small matter of the time and effort involved. The scientists call for moving the eggs every 2 minutes for 32 minutes total, which means transferring them a whopping 16 times. I was glued to my phone’s timer for the half-hour-plus like a character in a spy movie watching a bomb timer tick down toward detonation, while I simultaneously attempted to regulate the lukewarm bowl temperature. I wound up with water all over the counter — and my shirt.

Di Maio claims that the result is worth it. “I am a patient person, so I enjoy using the time for the good things,” he said. “It’s rewarding. I mean, I don’t care using up even an hour of my time to give people I love something very good.”

But I found the results to be … just okay. The eggs I cooked (which admittedly did not quite meet the scientific method, because my bath was often slightly warmer than the prescribed 86 degrees) had nice, consistently cooked, jammy yolks, but the whites were too soft for my liking.

I tried again in The Washington Post’s Food Lab, this time aided by a sous vide machine (immersion circulator), which I used to keep the water in the cooler bath circulating and to monitor the temperature. I found myself throwing in ice cubes to maintain a consistent 86 degrees. It was a slightly less chaotic process — and it helped that it wasn’t my first rodeo — but it was still stressful.

Again, my results were eggs with evenly cooked, soft centers, and again, the whites were gloopier than I liked, which also made peeling them without piercing them a challenge.

My colleagues and I decided to try them alongside a few other popular egg-cooking methods for comparison, including two for soft-boiling — an 8-minute boil and a 10-minute steam — and one for hard-boiling, a 13-minute steam that former recipes editor Ann Maloney judged to be the optimal approach for hard-cooked eggs.

Admittedly, they showed the flaw that the Italian scientists set out to fix: uneven cooking. In both soft-boiling methods, the yolks were more cooked around the exterior than in the center. But you know what? We didn’t mind. My colleagues and I all enjoyed the 8-minute boil the best, with its set whites and pleasantly gooey yolks. The 10-minute steamed eggs, we thought, would be good for applications where you might prefer them a little more set, such as a salade nicoise.

Personally, boiling will remain my preferred method, because steaming just means that there’s another thing to wash. I’m all for keeping things streamlined in my kitchen, which is why (sorry, science!) I don’t think I’ll be going back to the periodic method. But if you like an experiment, and you have a half-hour (and a dry shirt) to spare, it might be worth a try.

Di Maio certainly encourages it: “I would push people to try, because it’s a totally different experience, really.”

And he says the recent surge in egg prices might just encourage people to prepare them more carefully than ever. “Maybe this will push people to get more from these more and more precious ingredients,” he said. “Maybe they will try to use periodic cooking to extract nutrients with our technology, instead of wasting the properties with a quicker, less effective process.”