Ajitama have always been my favorite topping for ramen, hands down. These soy-marinated eggs can also be a healthy and convenient snack all on their own! You could even doll them up a little to serve as an izakaya-style appetizer. Or do what I do: pack one ramen egg in your bento box and save one for a low-carb side to your dinner. Try out this quick, easy ramen egg recipe! 

Jump to the recipe

ajitama soy marinated with pepper on table

What are Ajitama?

Ajitama is the abbreviated name for ajitsuke tamago.

These are the soft-boiled eggs that are served on top of your steaming hot bowl of ramen.

Kerplunk! In they go, to swim in miso. 

In Japanese, the name literally means “seasoned egg”. The kanji is 味 +付け+ 玉子. If you read each character separately, it says ‘flavor-attached egg’, which makes sense, right? They’re marinated. 

Ajitama are also called ajidama, tsuketetamago, ajitamago, nitamago, or hanjukutamago.

That’s a mouthful to remember if you don’t speak Japanese. Luckily, if you’re a foreigner at a ramen shop in Japan, you can just say tamago. They’ll know exactly what you’re trying to order: 

“Egg-u desu ne.”

In English, you can simply call them ramen egg.

Or if you want to sound like a ramen connoisseur, you could say steeped egg.

I’ve actually never heard anyone in Japan say ramen egg before. You’re more likely to hear a tourist say “What are the eggs in ramen?”

I’m counting on you to be able to explain!

Other times, people might refer to them soy sauce eggs or soy-marinated eggs.

There are also versions of flavored eggs in China and Korea as well.

I’m going to teach you how to make them Japanese-style below.

Ajitama Egg vs. Onsen Egg

If you’re looking for a recipe for onsen tamago, sorry, you’ve come to the wrong place.

Ajitama egg are marinated eggs with the light brown outside and creamy, custard-like yolk. Lots of people describe the yolk inside ajitama as jammy.

Onsen tamago literally means “hot spring eggs”. Originally, these eggs were cooked at low temperature in actual water from hot springs in Japan. Slow cooking the eggs at low temperature, the egg gets poached inside the shell. The  result is a firm yolk inside soft, milky egg whites. 

So basically, ajitama are like the opposite on onsen egg. The whites are firm and the yolk is soft, unless you decide to make yours hard-boiled. Remember that aji- means flavor in Japanese. So ajitama are the ones that are flavored and light brown.

ajitama marinating in soy and mirin with spicy red pepper

How to boil the perfect soft-boiled egg for making ajitama

To make soft-boiled eggs, you boil them for 6 to 8 minutes depending how soft you want your yolks. I do 6 minutes 30 seconds.

Take note that it’s important that you pay attention to the size of the eggs when you set your timer. 

The boil time is crucial and putting the eggs immediately in an ice bath.

Also, whether or not your eggs were just taken out of the fridge or at room temperature may also affect cooking time.  

Depending on your stove, you may have to adjust your boiling time up or down. 6 min 30 seconds to 7 minutes might be a good place to start.  

If you don’t mind your yolks being on the firmer side, I would recommend 7 minutes for your first trial.

What eggs do you use to make Ajitama?

To make these eggs, I use the best quality free-range eggs that I’m willing to pay for. 

If the chickens that laid your eggs are feed GMO-corn and soy, then that’s essentially what you’re eating too. 

“You are what you eat eats.” 

Saying this, I don’t use organic-certified eggs from Hokkaido…

because they’re $7 for a carton of six!

For 7 dollars, I’d buy my own hen.

The Soy Marinade for Ajitama (ramen egg)

Ramen shops in Japan typically marinade their eggs in the leftover braising liquid from the chashu pork. That’s some serious ramen business. 

And if you’re vegetarian or don’t eat pork, that kind of leaves you out.

The at-home kitchen standard for soy-marinated eggs in Japan, from everyone that I’ve asked, is basically a mix of these three ingredients:

1. Soy sauce

2. Mirin

3. Water

It would be hard to go wrong with a ratio of 1: 1: 1.

Other variations also include vinegar, chicken stock, konbu, or mentsuya (soba dipping sauce).

It’s also common to add a splash of sake, which is what I do.

Additional Ingredients to Marinade Ajitama

My Japanese mom in Gunma also marinates her soft-boiled eggs in miso. You may have seen miso-cured eggs if you watched “Salt Fat Acid Heat” on Netflix.

You can also add other umami ingredients like katsuo (bonito) flakes, dried shiitake mushrooms, or other dried fish.

For additional flavor, you can also experiment with ingredients like ginger, garlic, green onion and togarashi dried chili pepper. Personally, I usually add chili peppers or ginger.

A pro tip I learned is to use shoyu koji instead of soy sauce for the marinade. 

If you can get your hands on it, use traditionally brewed natural artisanal soy sauce for even better results. 

If you live someplace like Walworth, Wisconsin, you can still make some authentic-tasting ramen eggs with Kikkoman soy sauce, that’s brewed in Walworth, Wisconsin. (Fun fact.)

I use their organic soy sauce all the time.      

hole puncher to boil easy to peel eggs

The Secret to Making Soft-boiled Eggs Easy to Peel

In Japan, this trick is no secret. Back home in the US, I suspect most boiled egg-eaters don’t know this. My sister does, but she’s a food scientist.

The trick to making eggs easy to peel is so simple. All it takes is making one small hole in the base (the larger end) of each egg before putting them in the boiling water.

At the large end of each egg is a small air space. When you hard cook an egg, this air heats up, expands, and escapes through pores in the shell—but not before the egg white sets.

In Japan, you can buy an “egg hole-puncher” at any 100 yen store.

If you can’t find one of these where you live, Amazon is one option.

Otherwise, you may have to get creative. To safely make holes, you could try pin or tack (sterilized).

My Japanese mom uses a knife to crack each shell while the eggs are boiling in the pot. Keep in mind that this isn’t a beginner technique.

I recommend buying an egg piercer on Amazon, to save yourself from poking a hole in the side of your finger by accident.

Some “eggs-perts” express food safety concerns about poking holes in eggs. In Japan, it seems to be very common practice. In Germany, it seems to be well-known trick as well.

I don’t pretend to be an expert in food hygiene– please poke your eggs at your own risk.

Also, peel the eggs before they go in the soy marinade. 

Is it better to use fresh or old eggs to make ajitsuke tamago?

From my research, I read that if you make soft-boiled eggs from older eggs, they tend to be easier to peel. Apparently they have a larger pocket of air beneath the shell because of evaporation.

However, if you use the trick above, this makes it easy to peel fresh eggs.

I Photoshop pictures of food but even I’m not that fussy. I use whatever eggs that are out on the counter.

If you’re aiming to get the perfect shaped egg, then you may have more luck with fresher eggs.

In regards to taste, I haven’t noticed any difference. 

soft boiled eggs for ajitsuke tamago

How long do ramen eggs keep?

I don’t really have this problem.

Ramen eggs are such a versatile and convenient snack that it’s unlikely that I’ll have any that risk going to waste.

If you do keep yours longer, they will keep for up to four days, according to Mike Satinover, “The Ramen Lord”. 

You don’t have to take my word. Though, I think anyone who’s calls himself the “Ramen Lord” probably knows what the heck he’s talking about.

I keep them in air-tight container like Tupperware in the fridge.

Personally, I wouldn’t eat them after 2 or 3 days, especially if the yolks are soft. 

Can you reuse the marinade to make more ramen eggs?

Yes, and I do.

The marinade will keep in the fridge for about a month, from what I’ve read. I’ll use it for about a week tops to stay on the safe side. 

Also, if I’ve added any ingredients to the marinade such as dried chili or ginger, I’ll remove them the next day. You can add it to some meat and vegetables in a fry pan for a quick and simple stir-fry.

In Japanese, this is called mottainai. 

Nothing in a Japanese kitchen goes to waste.