Ikura, Tobiko, Mentaiko: Japanese Roe Guide

Ikura, tobiko and mentaiko turn up on Singapore menus constantly, usually with no explanation, and they get treated as interchangeable orange things. They are not interchangeable. Swap one for another in a dish and you have changed the dish, not the garnish.

The useful way to understand them is not as three ingredients but as three different solutions to one problem. Fish eggs are fragile and perishable. Before anyone can sell, store or serve them, they have to be stabilised with salt. What separates ikura, tobiko and mentaiko is at what scale that stabilising happens — and every difference in how they behave on a plate follows from that one decision.

The short version

Ikura is salmon roe, separated into individual eggs and cured loose. Big beads, thin skins, liquid inside. It bursts.
Tobiko is flying-fish roe, tiny and firm-skinned. It crunches.
Mentaiko is pollock roe cured with the sac intact, so the eggs never come apart. It spreads.

Or, put as a rule you can order by: ikura is punctuation, tobiko is texture, mentaiko is a sauce.

Ikura: stabilised one egg at a time

Ikura is salmon roe. The eggs are pulled from the skein and cured individually, typically in a brine built on soy and sake, which is why good ikura tastes savoury and faintly alcoholic-sweet rather than simply salty.

Because each egg is cured on its own, each keeps its membrane, and inside that membrane is liquid. This is the whole point of ikura and it is why it is expensive and why it is used sparingly. You are not buying flavour by volume. You are buying a delivery mechanism: a bead that survives being placed on something, then releases in one go when it is pressed.

That has a practical consequence for anyone eating it. Ikura should never be stirred in. The moment it is mixed through a dish, every bead has already burst and you have paid a premium for what is now just salty liquid. It goes on top, at the end, and it is the last thing to happen to the plate.

Ikura is not sujiko, and the difference proves the point

The distinction worth knowing at a counter: sujiko is the same salmon roe cured while still in its membrane, in a single lobe, rather than separated. It is darker, denser and much more concentrated, and it is used the way a paste is used rather than the way a bead is.

Which is exactly the relationship mentaiko has to loose pollock roe. Sujiko is to ikura what mentaiko is to a scattering of individual eggs. The species changes; the principle — cure it in the sac and it becomes a spread, cure it loose and it becomes a bead — does not.

Tobiko: so small that the skin wins

Tobiko is the roe of flying fish. The eggs are minute, far smaller than salmon roe, and the membrane is comparatively firm.

At that scale the ratio flips. In an ikura bead the interior dominates and the skin is a container; in a tobiko egg there is so little interior that what you actually experience is the skin. That is the origin of the characteristic crunch, and it is why tobiko functions less as a flavour than as a texture you can season a dish with.

It is also why tobiko is so often coloured. Because its own flavour is mild, it takes on whatever it is cured with — wasabi green, yuzu yellow, squid-ink black. Those are real preparations, not food dye for its own sake, though plainly dyed product exists too. If the colour is aggressive and the flavour is nothing, you are looking at the cheap version.

The common confusion is with masago, capelin roe, which is smaller again, softer, cheaper and much more likely to be dyed. If a dish is described as tobiko and the beads collapse rather than pop, it is probably masago.

Mentaiko: stabilised as a whole sac

Mentaiko is pollock roe cured with the sac left intact and seasoned with chilli. Fukuoka Prefecture’s own tourism guide describes karashi mentaiko as pollock roe soaked in a mixture of liquid seasonings including numerous spices such as chilli pepper, and calls it the flavour of Hakata.

Because the cure happens at the level of the sac, the individual eggs never become independent objects. What you get is a single soft mass, held loosely together by the membrane, that can be scraped out and used like a paste. That is the property that makes mentaiko different in kind from the other two: it is the only one of the three that can season a whole dish rather than sit on top of one.

We are not going to re-tell mentaiko’s history here, because it has its own post — what mentaiko actually is, how it is cured, and why Singapore kitchens put it on everything — and the dip we build with it has another. Read those two for the depth; what matters for this guide is the structural point: sac-level curing produces a spread, and a spread does a job a bead cannot.

Telling them apart in front of you

Four questions, in the order they are useful.

How big is it?

Salmon roe is the only one of the three you can pick out as an individual object without looking closely. If you can see distinct spheres from arm’s length, it is ikura. If it reads as a textured mass of orange, it is tobiko or masago. If it is not beads at all but a soft paste, it is mentaiko.

What does it do when you press it?

Ikura gives, then releases. Tobiko resists, then crunches. Masago simply flattens. Mentaiko has nothing to release — it smears.

How translucent is it?

Good ikura is glassy; you can see light through a bead. Cloudy, whitish ikura has usually been frozen badly or is old. Tobiko is opaque by nature, so this test says nothing about it.

Is it doing a job?

This is the one that separates a considered dish from a garnish. Ikura placed on something rich and hot is doing a job — the burst of cold salt is the point. Ikura scattered over a bowl of fried rice for the photograph is not, and it will be dead by the time the bowl reaches you.

Where all three land on our menus

All three are on the menu at 29 Hamilton Road, which is unusual enough to be worth spelling out, and the way they are used is a fair test of everything above.

Chickpea Hummus — macadamia tahini, ikura. Beads on a purée. The hummus is smooth, warm-toned and nutty; the roe supplies cold, salt and a burst. Nothing about that works with a paste. The full write-up is in our post on the macadamia tahini hummus.
Atlantic Seabass — yuzu beurre blanc, miso butter, ikura, and, in the menu’s own words, bloody crispy skin. Same logic against a butter sauce instead of a purée. Covered in detail in the seabass post.
Cassava & Taramasalata — twice-cooked cassava chippies, housemade labne, mentaiko XO, tobiko.

That last one is the dish that proves the framework, because it carries two of the three at once and gives each the job it is suited to. The mentaiko is worked into an XO-style sauce, which only works because mentaiko spreads. The tobiko goes over the top, where its crunch registers against the soft labne and the hard chippie. Neither could take the other’s place. Swap them and you get a gritty sauce and a wet garnish. There is a whole post on that dip — two roe traditions in one bowl — and it is the clearest thing on the menu for understanding what this restaurant is trying to do.

At Li’l Habibi, our smaller room at 55 Haji Lane, the same pairing appears differently: the chickpea hummus carries ikura there too, and the mentaiko taramasalata is served as a dip in its own right with tobiko, crispy shallots and chives rather than with cassava.

Buying and keeping it

If you are shopping rather than ordering: all three are cured, not cooked, and all three are perishable in the way cured fish is perishable — slower than raw, much faster than tinned. Buy ikura in the smallest quantity you will actually use, keep it cold and never refreeze it, because the beads will have burst by the time it thaws. Mentaiko keeps longer than either bead product because the sac protects it. Tobiko is the most forgiving of the three and the most likely to have been sitting somewhere.

One dietary note. All three are cured rather than cooked, and mentaiko marinades commonly contain alcohol-based seasonings, so they are not automatically suitable for everyone at the table. To answer the question the rest of our menu raises: Habibi-san is not halal — we serve pork and alcohol at both venues, and that is set out along with everything else people ask in our FAQ. If anyone in your party is pregnant, avoiding raw or cured fish, or has a seafood allergy, tell us when you book — the menu asks for exactly that.

Coming to try them

If you want all three in one sitting, it is the hummus and the cassava, and it is not an expensive way to cover the whole subject. Both are on the mezze section, which is also the part of the menu with the most going on. The full menu is here, the gallery shows how the plates actually land, and you can book a table — Tuesday to Sunday, 5pm to 11pm, 29 Hamilton Road.

For the wider picture, our guide to Japanese food in Singapore is the place to start, and the dishes-beyond-sushi guide covers the rest of the vocabulary this one assumes.