WASHINGTON• It has never been easier to get poke, the marinated raw ahi tuna that is the unofficial food of Hawaii, elsewhere.

You will find the dish - pronounced po-kay - in Minnesota, Indiana and landlocked Colorado.

There is poke from Hong Kong to Singapore. You can buy poke kits in grocery stores and you do not even have to leave your house for it in Chicago - Asap Poke, a delivery- only restaurant, will bring it to you.

Homesick Hawaiians must be thrilled, right?

"I tried one and I swore never to go again," said Mr Sonny Acosta, 30, who moved to New York from Honolulu two years ago. "It's not really poke."

It is not just that poke tastes better when you are in Hawaii. It is that mainland restaurateurs, bandwagoning on what they see as the biggest trend of the year, have changed it into something altogether different - something that people from Hawaii say does not respect their cultural heritage.

It plays into an impassioned debate in the food world now about whether a dish prepared outside its original context is an homage or crosses the line into appropriation.

Shops in Washington are putting corn in it. They are topping it with kale. They are putting the fish on top of "zoodles" or zucchini noodles as customers order down a line, Chipotle-style. They are adding a sprinkle of cilantro or even sweet strawberry sauce.

And, adding insult to injury, some are not even spelling the word correctly.

The concept of poke, a word that means "to slice" in the Hawaiian language, has a long history, but the poke bowl, with rice and sauces, is a relatively modern invention.

"The term is Hawaiian, but the traditions behind it (have) far more of a Japanese influence," said Professor Kealalokahi Losch, who specialises in Hawaiian studies at Kapi'olani Community College in Honolulu.

"It's part of the fabric of what we would refer to as local culture, which is a conglomeration of all the different cultures that are here."

Native Hawaiians would originally slice up smaller reef fish and serve them raw. But with the arrival of Japanese workers in the late 1800s, the predominant poke fish shifted to ahi tuna.

Poke bowls with rice - a cultural mash-up of Hawaiian flavours and Japanese donburi - became popular in restaurants in Hawaii only in the past three decades, Prof Losch said. They are often served with minimal toppings from a smaller range of flavours, to let the taste of the fish come through.

There are a few reasons poke has boomed elsewhere: It is raw and full of veggies, so it is branded as healthful. And it is relatively simple to open a shop.

"From the business side, it's so easy to make," said Martha Cheng, author of The Poke Cookbook. "You don't need a full kitchen, you don't need an oven, you don't need a grease trap."

It is also colourful and inherently Instagrammable - especially if you add lots of toppings, such as the pink-and-green watermelon radish and neon-orange masago, a type of fish egg, available at Poke Papa in Washington.

But it is this "mainland poke", as they call it in Hawaii, that looks different from what you would find in restaurants and grocery stores on the islands.

In Washington, shops are offering more toppings than in a frozen yogurt bar, provoking those who serve a more traditional version of poke - such as Abunai, whose owner, Ms Akina Harada, has native Hawaiian ancestors - to call out the others: This spring, she posted a sign outside her downtown restaurant: "Friends don't let friends eat FAKE poke."

The option of pineapple might be the gravest offence to some locals in Hawaii. It is already a cultural irritation due to Hawaiian pizza - invented in Canada.

"It's absurd because people feel like you can throw pineapple on anything and call it Hawaiian," said Mr Blaine Saito, 35, who moved to Washington from Honolulu to work for the federal government.

Restaurateurs who offer plenty of toppings, such as Poke Papa owner Kerry Chao, say people from Hawaii who come into their shops do not usually load up on the coconut flakes or Korean pepper sauce.

For Mr Chao, it is about appealing to both: those craving a taste of home and the mainlanders who want a variety of flavours.

"You get people who complain that we have toppings and I don't understand," said Mr Chao, who is originally from Missouri and acknowledges his poke is not authentic. "Just don't get the toppings."

Some restaurants, in an attempt to make an unfamiliar word easier for their customers to pronounce, changed the spelling to "poki".

But it is imposing a Western spelling and diacritical mark on a Hawaiian word. The spelling, for some Hawaiians, is what makes mainland poke cross the line from ill-intentioned homage to flat-out cultural appropriation.

"It's sort of the continuation of the colonisation of our people, where they tell us how we should act and how we should spell and how we should eat our food," said Ms Noelani Puniwai, an assistant professor of Hawaiian studies at the University of Hawaii, Manoa.

Mr Gary Ngo, a founding partner of Poki District, said he was never trying to do a real Hawaiian restaurant in the first place.

"It's an extra talking point for people," said Mr Ngo, who changed the spelling as a pronunciation aid. "Even though some people complain that we're spelling it wrong, we never think we are 100 per cent authentic Hawaiian poke."

While some people from Hawaii are not thrilled about seeing a staple of their diet reduced to the latest fad food, poke's sudden popularity is also causing alarm among environmentalists.

The most popular fish for poke is ahi tuna, which is overfished in certain regions of the world. With fisheries already in decline, the use of ahi is not something "that should be spread across the United States", Ms Puniwai said.

Chefs in Hawaii experiment with variations on poke too, but the difference is that they approach it with an understanding of the heritage, said Mr Mark Noguchi, a Hawaiian chef who is a partner in Lunch Box, a Honolulu cafe. He has been impressed by beet poke, for instance, because it mimics the colour and texture of ahi.

"Our food, that is our sense of place," he said. "You can mimic it, but you can't re-create the soul of it. There's no amount of Instagramming or Googling that will show you our soul. That's what you can taste."

WASHINGTON POST