Cooking a perfect boiled egg takes at least half an hour, physicists have claimed, as they say the best method for a tasty and nutritious breakfast involves switching repeatedly between pans of different temperatures.

As anyone who has ever struggled to get an egg to their liking will know, an even boil is difficult because the yolk and white cook at different temperatures. Cooking at a vigorous boil works for the white, which requires temperatures of 85°C (185°F) for optimum consistency, but can also result in a hard yolk, which only needs 65°C (149°F). Chefs have found immersing the egg in a water bath at a steady temperature of between 60°C and 70°C (140°F and 158°F) can lead to better cooked yolks, but this sous vide method also risks an undercooked white.

Now, at the University of Naples, Italy, and his colleagues have found a better way to evenly boil an egg, by swapping it between boiling water and 30°C (86°F) water every two minutes for eight cycles, taking a total of 32 minutes.

“Many people have tasted [the egg cooked in this way], and they were amazed by the taste and the texture,” says Di Maio. “Yes, it takes more time than usual cooking, but I think if you love someone, you should invest your time to do something properly. This is how to properly do an egg.”

To develop this method, Maio and his team first created a model of how an egg cooks by calculating the way energy spreads from the shell to the centre over time, using two equations to describe this process. By solving these equations, they found that the best way to evenly cook it would be to alternate between two different temperatures, which allows the two parts to cook separately.

After cooking eggs in this way, the team studied them using spectrometry and an MRI-like scanner. The researchers found that proteins in the egg yolk were less denatured and in the white they were more denatured, in each case meaning that part was better cooked, than in soft-boiled or sous vide eggs. They then asked people to try the eggs cooked with their method, and found that the egg white was slightly sweeter and the yolk was less sweet than in eggs cooked in other ways. They also found the white’s texture was similar to a soft-boiled egg, while the yolk was more like a sous vide egg.

Free newsletter

Sign up to The Daily

Sign up to newsletter

The periodic egg also contained a higher amount of nutrients, such as antioxidants called polyphenols, compared with soft-boiled or sous vide eggs, though Di Maio and his team don’t know why.

“It’s fun and it’s good for a laugh,” says at the University of Bristol, UK. “Spending 30 minutes taking an egg in and out two different temperatures of water just to get it to cook slightly better than you would by others means where you can leave it alone is, shall we say, not very practical.”

Cooking food using alternately hot and cold environments isn’t a new idea, says at AgroParisTech in France. “It is not original, as it was proposed about one century ago for meat.” It is also important to compare the eggs cooked in this way to eggs cooked sous vide at different temperatures, as this can dramatically change the cooked egg, he says.

Archaeologists have cooked and prepared five wild birds using only fire, their hands and stone tools to learn more about the culinary abilities of Neanderthals. The experiment shows it took considerable manual skill for our ancient relatives to butcher animals using flint blades without injuring themselves.

Neanderthals inhabited Europe and Asia until around 40,000 years ago.  have been found at many Neanderthal sites, and we also have evidence they and

at the Catalan Institute of Human Paleoecology and Social Evolution in Tarragona, Spain, says by replicating ancient activities such as cooking and butchering with the tools available at the time, scientists can gain insight into how prehistoric humans lived.

She and her colleagues wanted to better understand archaeological bird remains associated with Neanderthals that were recovered from deposits in Portugal, which date to approximately 90,000 years ago.

The team selected five birds that had died in a Portuguese wildlife rehabilitation centre and were of a similar size and species to those found in the archaeological deposits: two carrion crows (Corvus corone), a common wood pigeon (Columba palumbus) and two Eurasian collared doves (Streptopelia decaocto). The tools used in the experiment were flint flakes prepared by lithic technology students.

All five birds were plucked by hand. A crow and a dove were butchered uncooked and the remaining three birds were baked on a bed of coals. The cooked birds could be easily pulled apart without stone tools, but the raw birds required considerable effort using the flint blades.

Subscriber-only newsletter

Sign up to Our Human Story

Sign up to newsletter

“Palaeolithic knives were indeed very sharp, requiring careful handling,” says Nabais. “The precision and effort needed to use these tools without causing self-injury emphasised the practical challenges Neanderthals might have faced in their daily food-processing activities.”

Once the butchering was complete, the researchers prepared the bones and then analysed them for distinctive signs caused by the stone tools and the fire. They also identified wear marks on the flint tools.

The burn marks and tool scars were then compared with Neanderthal food remains from the Figuiera Brava and Oliveira archaeological sites, both in Portugal. Bird bones with burning stains and cut marks found at the sites align with those seen in the team’s replications, says Nabais.

“Our experimental study demonstrated that raw birds processed with flakes show distinctive cut marks, especially around tendons and joints, while roasted birds show burn marks and increased fragility, leading to bone breakage,” she says. “These finds help distinguish human-induced modifications from those caused by natural processes or other animals, such as trampling or the activity of rodents, raptors and carnivores.”

Neanderthals were skilled enough to catch and cook small, quick animals like birds, says Nabais. “This study highlights the cognitive abilities of Neanderthals, demonstrating their capacity to catch and process small, fast-moving prey like birds, thus challenging the traditional notion that Neanderthals were not capable of such complex tasks.”

at the University of Wollongong, Australia, says experimental archaeology is like reverse engineering where you compare what happens to a modern sample with archaeological material to try to interpret what may have happened in the past.

In this case, one of the main findings was that cooked birds don’t need tools to be prepared for eating, which could mean some bones won’t necessarily have tool scars. “They learned you can just rip a cooked wild bird apart the same way we eat a barbecue chicken,” says Lin.

Why we use eggs for baking

Egg substitutes and why they work

A recipe for the perfect eggless chocolate cake

Vegan chocolate cake ingredients: