Ramen eggs (ajitama): exact boiling times and the marinade
A ramen egg, ajitama or ajitsuke tamago, is a soft-boiled egg soaked in a sweet soy marinade: a set white, an amber surface and a yolk like thick custard. Everything depends on the boil. A few seconds too long and the yolk sets; too short and the white is still soft when you peel it.
How long to boil
Times for eggs lowered into water at a full boil at sea level, then moved straight into an ice bath. "Jammy" is the classic ramen yolk; "softer centre" keeps the middle runnier. The ice-bath column is how long the yolk takes to stop warming up: the egg is ready to peel after that.
| Size | From the fridge | At room temperature | ||||
|---|---|---|---|---|---|---|
| Jammy (classic) | Then in ice | Softer centre | Jammy (classic) | Then in ice | Softer centre | |
| S 50 g | 6:34 | 3:21 | 5:48 | 5:30 | 3:19 | 4:42 |
| M 58 g | 7:15 | 3:41 | 6:23 | 6:03 | 3:39 | 5:11 |
| L 68 g | 8:02 | 4:05 | 7:05 | 6:43 | 4:03 | 5:45 |
| XL 76 g | 8:39 | 4:24 | 7:37 | 7:14 | 4:21 | 6:11 |
For a medium egg (58 g) straight from the fridge: boil 7:15, then 3:41 in iced water. Sizes are European weights in the shell; a US Large is close to the M row. For other countries' sizes, see egg sizes around the world.
Why the ice bath matters
An egg keeps cooking after it leaves the pot, as the heat stored in the white moves into the yolk. Plunging it into iced water stops that quickly, which is what gives a ramen egg its look: a firm rim of yolk around a soft, glossy centre. Cooled slowly on the counter, the same egg would come out more evenly set. See an even or a contrasting yolk.
Step by step
- Bring a pot of water to a rolling boil. Use enough water to cover the eggs by a couple of centimetres so it comes back to the boil quickly.
- Lower the eggs in gently with a spoon and start the timer at once.
- Prepare the ice bath while they boil: a bowl of water with plenty of ice.
- When the timer rings, move the eggs into the ice and leave them for the time in the table.
- Peel under a trickle of water, starting from the wide end where the air pocket is.
- Marinate in the fridge. A classic marinade is one part soy sauce, one part mirin and two parts water; some cooks add a splash of sake or a little sugar. Put the eggs in a bag or a small container so they stay covered.
How long to marinate
- 4 to 6 hours: lightly seasoned, pale brown outside.
- Overnight, about 12 hours: the classic result, amber white and seasoned through.
- A day or more: darker and saltier. The salt slowly firms the outer layer of the yolk, so for long soaks use the "softer centre" time.
Keep the eggs in the fridge and eat them within a few days.
Open the calculator, choose Jammy and the ice bath: the timer tells you when to move the eggs and when they are ready to peel.