Eating vegan in Japan: the dashi problem and how to actually solve it

A block of katsuobushi is one of the hardest foods anyone makes on purpose. Skipjack tuna is simmered, deboned, and smoked over hardwood for weeks, then deliberately inoculated with Aspergillus glaucus mould and left to grow in a humidity-controlled room called a muro. The mould's threads push into the flesh and pull out moisture the smoking missed, while its enzymes break down surface fat. The block is sun-dried, brushed, and reinoculated, three to six times over a total production span of up to four months to qualify as the premium grade, hon-kare-bushi. What comes out the other end has under 15 percent moisture, tastes almost nothing like fish, and is shaved into curls with a wooden plane called a kezuriki. That shaved flake, simmered briefly in water, is dashi, and dashi is the base of miso soup, most noodle broths, tamagoyaki, simmered vegetable dishes called nimono, and the dipping sauces served with tempura and soba. A dish can look entirely vegetable, rice or tofu and still carry katsuobushi in its stock, which is the single fact that trips up nearly every first-time vegan visitor to Japan.

The other common base is niboshi, whole dried sardines simmered into a stronger, more mineral stock used in some ramen and udon shops and in older home cooking. Either way, the tell is the same: if a broth in Japan tastes deeply savoury rather than merely salty, assume it is built on a fish stock until someone tells you otherwise.

In 1908 the chemist Kikunae Ikeda isolated glutamate from kombu broth and named the taste it produced umami. One of his students, Shintaro Kodama, later found a second umami compound, inosinate, concentrated in katsuobushi. When the two are combined, they do not simply add together: sensory testing found that a 1 to 1 ratio of glutamate to inosinate tastes roughly seven to eight times stronger than either compound alone, a multiplication rather than a sum. That synergy is why traditional awase dashi pairs kombu with katsuobushi, and it is also why the vegan substitute is not a downgrade. Shiitake mushrooms are rich in guanylate, a third umami compound that synergises with kombu's glutamate through the same multiplying mechanism. A dashi made from kombu and dried shiitake hits the same chemical trick the traditional version does, just with a different partner molecule, which is the actual reason shojin ryori tastes complete rather than like food with something left out.

Shojin ryori is the temple cooking that developed inside Zen Buddhist monasteries, and it is the one branch of Japanese cuisine that is vegan by design rather than by substitution. Meat, fish, eggs and dairy are excluded on the principle of non-harming, and so is a category most Western guides skip entirely: gokun, the five pungent roots, meaning garlic, green onion, Chinese chives, shallot and asafoetida. Buddhist teaching in this tradition holds that these foods overstimulate desire and anger when cooked and dull spiritual clarity when eaten raw, and their smell was considered disruptive to communal meditation, so a dish can be entirely plant-based and still not count as proper shojin ryori if it leans on garlic and onion the way most modern vegan cooking does. A meal is built around tofu and soy proteins, seasonal wild and mountain vegetables, and dashi made from kombu and shiitake, arranged to hit the five colours, five cooking methods and five tastes that the tradition treats as a form of discipline as much as a menu.

You can eat it at temple lodgings, shukubo, on Mount Koya in Wakayama Prefecture, where staying overnight typically includes a shojin ryori dinner and breakfast, and at a smaller number of standalone restaurants in Kyoto that serve it to the public without an overnight stay. It is the one context in Japan where you can order without cross-examining the kitchen, because the entire point of the food is that it needs no exception.

Japan is genuinely harder for a vegan traveller than most of Western Europe, and a guide that says otherwise is setting you up to arrive hungry. The reason is not hostility, it is that dashi is load-bearing in a way Western stocks are not: a French kitchen can leave meat stock out of a vegetable soup without changing what the dish is, but a Japanese kitchen built around dashi treats it the way a Western kitchen treats salt, as a background element nobody thinks to mention because it does not register as an ingredient choice.

That said, the picture has moved. Before the Tokyo Olympics, originally scheduled for 2020, the Japanese government began funding restaurant guidelines, subsidies and certification marks to help kitchens identify and label vegetarian and vegan dishes, and the number of vegan restaurants nationwide rose to roughly 1,000 in 2020 from about 400 in 2018, concentrated overwhelmingly in Tokyo and Kyoto. VegeProject Japan, which has certified products unofficially since 2016, remains the mark you will actually see on shelves; a formal government JAS vegan certification exists since 2023 but had certified fewer than 10 businesses as of that year because it requires in-person inspection. Outside the two big tourist cities, and especially in smaller towns and rural onsen regions, the improvement has been much smaller, and a traveller should plan meals in advance rather than assume options will appear.

In everyday Japanese usage, bejitarian is frequently understood to mean no visible meat, which leaves room for a kitchen to serve you a dish built on bonito or sardine stock in good faith, because from their side of the counter nothing meat-like is on the plate. Telling a server you are vegan, vegan or bīgan, is safer but the word is still new enough in Japan that not every kitchen will know exactly what it rules out. The approach that reliably works is naming the specific things you do not eat rather than the category you belong to.

Miso soup is the clearest case: the paste itself is soy, but the liquid is almost always dashi, so a bowl at a typical restaurant carries bonito or sardine stock even though nothing about its appearance suggests fish. Tonkotsu ramen broth is simmered pork bone for hours and is never accidentally vegan, but the base wheat noodles in most ramen are just flour, salt and water; the exceptions are a minority of shops, often higher-end ones, that add egg to the noodle dough for colour and texture, so asking about the noodles specifically is worth it even when the broth is clearly a lost cause. Tamagoyaki, the rolled omelette common at breakfast and in bento boxes, is dashi mixed into beaten egg, which fails on two separate ingredients at once. Gyoza wrappers are flour and water, but the filling is usually pork and the dipping sauce commonly contains dashi or fish sauce; vegetable gyoza exist on some menus but need to be asked for by name. Japanese sweets lean on gelatin in western-style desserts and occasionally in wagashi glazes, so a dessert that looks like fruit and bean paste can still carry it.

Japan's convenience stores, called konbini, are open around the clock and stocked densely enough to function as an actual meal plan. Plain onigiri, salt or umeboshi filling, is reliably vegan at the three major chains, FamilyMart, 7-Eleven and Lawson, and reading the small ingredient panel on packaged items catches the tuna mayo and salmon varieties before you buy them. Lawson's upmarket spinoff, Natural Lawson, concentrated in bigger cities, carries a noticeably wider range of plant milks, tofu snacks and salad options than a standard branch. Tokyo's Asakusa neighbourhood has the country's first fully vegan convenience store, stocking packaged meals with no ingredient checking required at all. Beyond convenience stores, Indian restaurants, which are common throughout Japan and routinely offer a vegetable thali or dal that is vegan by default, and dedicated vegan cafes concentrated in Tokyo's Shibuya and Kyoto's older neighbourhoods, are the two most reliable categories of sit-down meal for a traveller without fluent Japanese.

The instinct to treat dashi as an ingredient a kitchen simply forgot to disclose gets the culture backwards. Dashi functions in Japanese cooking closer to how salt or stock functions in French technique: a structural element so basic that naming it feels, to the cook, like naming water. Asking a chef to leave it out is not correcting an oversight, it is asking them to rebuild the dish's foundation, which is a bigger request than it looks like from outside the kitchen and is one reason smaller, traditional restaurants sometimes decline rather than improvise. The travellers who eat best in Japan are the ones who plan around dishes built to be vegan from the start, shojin ryori, Indian food, dedicated vegan cafes and konbui staples, rather than the ones who expect every traditional restaurant to substitute on request. That is a real limitation, not a failure of etiquette on either side, and it is worth knowing before you land rather than after your first bowl of miso soup.

Learn to ask about dashi by name rather than saying vegetarian, because the word alone will not stop bonito stock from arriving. Seek out shojin ryori at least once, ideally with an overnight stay at a temple lodging on Mount Koya, because it is the only cuisine in the country built vegan from its founding principles rather than adapted to be. And treat Tokyo and Kyoto as a different trip from the rest of Japan: the vegan infrastructure that arrived around the Olympic years is real, but it has not reached most smaller cities yet, and a rural itinerary needs a grocery store and a konbini as backup, not a hope that the next restaurant will have a vegetable option.