What’s Actually in Japanese Mayo? (And Why It Tastes Like Heaven in a Bottle)

Okay, listen.

I didn’t think I’d ever write a love letter to mayonnaise. But here we are. Specifically, Japanese mayo — also known as Kewpie, aka that cute little bottle with the creepy-cute naked baby on it. If you’ve ever slathered some on okonomiyaki, dipped a fry in it, or eaten it straight from the bottle (I’m not judging), you know exactly why this deserves a blog post.

But here’s the thing.

People keep asking:
“What’s actually in Japanese mayo?”
Like, what’s the secret sauce (literally) that makes it so different from the gloopy stuff you find in Western fridges next to the expired pickles?

Read on, mayo lovers. It’s about to get eggy.

First, Let’s Talk About Regular Mayo

You know the kind. The jar your grandma pulled out for tuna salad. The one that’s… fine? Basic? The mayonnaise equivalent of a polite “I’m good, thanks” text.

It usually contains:

• Whole eggs
• Vinegar
• Oil (usually soybean or canola)
• Salt
• Sometimes mustard or lemon juice
• Preservatives if it’s store-bought

It’s got a pretty neutral flavor. Creamy, tangy, and… well, a little boring if we’re being honest. It’s the Toyota Corolla of condiments.

Reliable, yes. But thrilling? Not so much.

Enter: Japanese Mayo (aka Kewpie)

Oh baby. This is a whole new condiment universe.

The moment you taste Japanese mayo, your taste buds throw a tiny party with sparklers. There’s a depth, a richness, a zing that regular mayo just can’t match.

But why does it taste so different?

Let’s break it down.

The Real Ingredients in Japanese Mayo

Here’s what’s in a standard bottle of Kewpie (based on the Japanese version — not the slightly altered American one):

🥚 Egg Yolks (Just the yolks!)

This is the #1 game changer.

Unlike Western mayo that uses whole eggs, Japanese mayo only uses the yolks. That gives it:

• A richer, more velvety texture
• A deeper, slightly umami flavor
• That smooth-as-silk consistency you lowkey want to bathe in (don’t do that)

True story: I once tried to make a sandwich with regular mayo after a month of using Kewpie and it was like someone swapped my fancy memory foam mattress with a pile of cardboard. Not. The. Same.

🍚 Rice Vinegar or Apple Cider Vinegar

Instead of the harsh white vinegar we usually see in Western mayo, Kewpie goes for softer, sweeter vinegars like:

• Rice vinegar
• Apple cider vinegar
• Sometimes a touch of malt vinegar

This gives Japanese mayo its signature tang without the bite. It’s like a friendly zing instead of a sour slap in the mouth.

🧂 MSG (Yes, and thank goodness)

Don’t freak out. MSG is basically misunderstood. It’s a flavor enhancer, and guess what? It’s what gives Kewpie that savory, addictive, can’t-put-it-down taste. You know the one.

It’s why you say, “Hmm, I’ll just add a bit” and suddenly you’re scraping the bottle with a spoon.

🌽 Vegetable Oil (Usually soybean)

Fairly standard, but in Japanese mayo, it’s used in a way that supports the creamy texture without feeling greasy or overwhelming.

🍋 Mustard Powder or a Touch of Spice

Just a little bit. Not enough to make it spicy, but enough to give it depth. Think of it like a seasoning whisper.

But Wait… What Makes It So Addictive?

So glad you asked.

It’s the combo of all those ingredients — plus the balance. Japanese mayo has this almost magical ability to walk the tightrope between creamy and tangy, rich and bright, comforting and surprising.

Also, let’s not ignore the umami factor. Thanks to the egg yolks and MSG, Kewpie taps into your brain’s “YES, I NEED MORE” pleasure center.

I once dipped pizza crust in it. Changed my life.

Real-Life Story: That Time I Took Kewpie Camping

True tale.

I went camping with some friends. Someone brought hot dogs. I brought Kewpie.

They laughed.

“Why would you bring mayo to a campfire?”
“Gross, who puts mayo on hot dogs?”
“Are you okay?”

But then… I squirted a little Kewpie on mine. Gave one friend a taste.
And guess what?

They. All. Converted.

We ended up eating mayo sandwiches because we ran out of hot dogs. One guy said he’d trade his entire trail mix stash for another squirt. That bottle of mayo became camp currency.

Moral of the story?
Bring Kewpie. Always.

How to Use Japanese Mayo (a.k.a. Put It on Everything)

Not sure where to start? Here are some Kewpie-approved ideas:

• 🍟 Fries – You haven’t lived until you’ve dipped sweet potato fries in Kewpie.
• 🥪 Sandwiches – Use it in egg salad and prepare for applause.
• 🍕 Pizza crusts – Yes. Try it. Don’t overthink it.
• 🥗 Coleslaw – Adds an umami kick to slaws and dressings.
• 🧆 Takoyaki and Okonomiyaki – The classics. It’s basically illegal to not use it here.
• 🍚 Rice bowls – A squirt on top of fried rice or donburi? Yes please.
• 🥩 Burgers and steak – Just trust me.

Also, pro tip: mix it with sriracha and call it spicy mayo. Instant sushi bar vibes.

Can You Make Japanese Mayo at Home?

Yep! It won’t be exactly like Kewpie, but it’ll come close. Here’s a super simple DIY recipe:

DIY Japanese Mayo Recipe

• 2 egg yolks
• 1 tbsp rice vinegar
• 1 tsp Dijon or mustard powder
• 1/2 tsp sugar
• 1/2 tsp salt
• 1 cup neutral oil (canola or soybean)
• Optional: a pinch of MSG (do it, live a little)

Whisk the yolks, vinegar, sugar, and salt. Slowly drizzle in the oil while whisking like a boss until it emulsifies. Boom. Japanese-style mayo at home.

Fun Fact You Didn’t Ask For

The Kewpie brand was founded in 1925 by Toichiro Nakashima, who was inspired by Western mayonnaise but wanted to make it better for Japanese palates. Hence the egg yolks and rice vinegar.

Also, the baby mascot? It’s based on a 1909 American cartoon. Because nothing says delicious like a naked cherub holding a bottle.

So… What’s In Japanese Mayo?

To recap, Japanese mayo includes:

• Egg yolks (no whites!)
• Rice or apple cider vinegar
• Vegetable oil
• MSG for that umami magic
• A little mustard or spice
• Zero guilt and all the joy

And what’s not in it?

• That weird gloopy texture
• That vinegar slap
• The disappointment of regular mayo

Final Thoughts: Should You Try It?

Only if you:

• Eat food
• Have taste buds
• Enjoy happiness

Seriously. Whether you’re a foodie, a condiment snob, or just mayo-curious, Japanese mayo deserves a spot in your fridge.

One squeeze and you’ll never go back.

Try It, Then Thank Me Later

If you’ve made it this far, chances are you’re either already on your way to buy Kewpie, or you’re reconsidering your mayo life choices.

Either way, I hope you learned something, laughed a little, and maybe now understand why I once brought a bottle of mayo to a wedding (don’t ask).

And hey — if you do end up trying Japanese mayo, let me know what you put it on first. Fries? Pizza? A spoon?

Drop me a comment, shoot me a DM, or just send me a psychic mayo-flavored high-five.

Until next time… stay creamy, my friends.