Italian scientists develop "Periodic Cooking" method for the perfect egg

Cooking an egg might seem simple, but achieving the perfect texture and flavor can be surprisingly tricky. To solve this culinary challenge, researchers at the Italian National Research Council’s Institute of Polymers, Composites, and Biomaterials have developed a new technique known as "Periodic Cooking."

The science behind egg cooking temperatures
Eggs require two distinct temperatures to cook properly. Egg yolks begin to set at 65°C, while egg whites require 85°C to fully solidify. This temperature gap often makes it difficult to achieve the perfect balance between a tender yolk and a properly cooked white.

Limitations of sous vide cooking
Sous vide — a popular method among chefs — involves sealing eggs in vacuum bags and cooking them at low temperatures (60-70°C) in a water bath for extended periods. However, this technique can leave egg whites only partially set, since only one protein type coagulates at these lower temperatures. Moreover, sous vide cooking can reduce the nutritional content of eggs.

Periodic Cooking: Method and advantages
The researchers’ periodic cooking method involves alternating the eggs between boiling water (100°C) for 2 minutes and cold water (30°C) for 2 minutes, repeating the cycle for a total of 32 minutes. According to the research team, this alternating process results in a perfectly tender yolk and fully set, yet soft, egg whites. The technique also helps retain both flavor and nutrients.

Nutritional and chemical benefits
Analyzing the nutritional content of eggs cooked using this method, scientists found that periodic cooking preserved higher levels of essential nutrients, including beneficial polyphenols. This makes the method particularly attractive for health-conscious consumers.

Applications beyond eggs
The researchers believe periodic cooking could be applied to a wide range of foods beyond eggs, helping to enhance both texture and nutritional value. The alternating heat-transfer process offers potential applications in cooking vegetables, meats, and other delicate ingredients that benefit from precise temperature control.