Traditional Scottish haggis is banned in the United States. With Burns Night looming, how do fans satisfy their taste for oatmeal and offal?

For aficionados, it is the "great chieftain o' the pudding-race".

To sceptics, however, it is a gruesome mush of sheep's innards - and for decades American authorities have agreed.

Authentic Scottish haggis has been banned in the United States since 1971, when the US Department of Agriculture (USDA) first took a dim view of one of its key ingredients - sheep's lung.

While millions of people around the world will enjoy, or endure, a Burns Night helping on 25 January, those in the US who want to celebrate Scotland's national bard in the traditional manner are compelled to improvise.

We're lucky if some of them take more than a mouthful Haggis fan Jim Short in LaGrange, Georgia

Some choose to stage offal-free Burns suppers, and for most people not raised in Scotland, the absence of the dish - comprising sheep's "pluck" (heart, liver and lungs) minced with onion, oatmeal, suet and spices, all soaked in stock and then boiled in either a sausage casing or a sheep's stomach - might be no great hardship.

But for many expat Scots and Scots-Americans, the notion of Burns Supper without haggis is as unthinkable as Thanksgiving without turkey.

According to custom, the haggis should be paraded into the room with a bagpiper before Robert Burns' poem Address to a Haggis is recited and the dish is served as the main course.

To purists, removing the haggis from the equation, or replacing it with vegetarian version, is heresy.

"It would be difficult to do an address to the chicken," complains the Spectator's Alex Massie, who each January uses his column to rail against US haggis prohibition.

At one time it might have been a marginal issue, but a Scottish heritage movement of Americans eager to connect with their Caledonian ancestry has been in the ascendency since the first Tartan Day was celebrated in New York in 1982.

Image caption Bagpipers at Tartan Day in New York

Native-born Scots may cringe at plaid-draped Americans proclaiming kinship with ancient clan chiefs, but Highland games across the US can attract crowds of up to 40,000 and Scottish societies exist in virtually every state and major city. In 2008, President George W Bush officially proclaimed 6 April as Tartan Day on which "the contributions of Scottish Americans" should be celebrated.

If you say it's grainy and slightly chewy that doesn't sound so attractive Fiona Burrell, Edinburgh New Town Cookery School Haggis not just for Burns Night

Against this backdrop, a mini-industry has emerged with American firms from Texas to New England manufacturing lung-free haggis for the US domestic market each January.

Retired healthcare executive Ronald Grant Thurston, 76, started producing McKean's Haggis in Bangor, Maine, after a visit to Glasgow, the birthplace of his wife Isabella.

He uses imported Scottish cereals and US-reared offal - British beef and sheep products having been banned from import since 1989 - and insists the product is none the worse for the absence of its missing ingredient.

"As an American who's not used to eating lungs, it's an improvement," he says.

Critics, however, complain that this Transatlantic version can never match the authentic Scottish product.

Massie, who staged numerous American Burns Suppers during his five years as The Scotsman's Washington correspondent, concedes the US versions often "aren't bad".

Haggis, served US-style R Juge Gregg, president of the Saint Andrew's Society of Washington DC, which holds an annual Burns Night dinner: There's always a certain level of trepidation because haggis has a reputation as not necessarily the tastiest of morsels. The US isn't known for eating all parts of the animal. But there are very few dishes I can think of that live up to the status of having been immortalised in a poem, so it's something that folks take seriously. I've been surprised at the positive response. I usually hear quite a few comments like 'This is better than I thought it would be,' or even 'This is pretty good'. We have the full pomp and circumstance - the piping in and the reading of Address to a Haggis. It's served as the first course. It's a centrepiece because of the presentation but we also have a separate entree [main course] such as fillet of beef. We get our haggis from a kitchen in Texas. I quite enjoy the US product. I've not had the Scottish version but I look forward to trying it some day.

But he says their texture tends to resemble that of pate more than the haggis he grew up with in Scotland.

"Without the sheep's lung it's not authentic," he says. "It's too sausagey. It lacks the lightness the lungs help create."

Scottish politicians, eager to encourage both exports and tourism, have led efforts to overturn the ban. Holyrood's Rural Affairs Secretary Richard Lochhead has repeatedly lobbied Washington to reverse its policy.

As it stands, however, lungs are "considered an inedible item" in the US, says a spokesman for the Food Safety and Inspection Service.

And it would be difficult to argue that the US is currently clamouring for haggis on the shelves of its superstores. The market for Thurston's haggis - expat Scots, Burns enthusiasts and Highland games attendees - is passionate but somewhat niche.

A 2003 survey suggested that a third of US visitors to Scotland believed the haggis was an animal. Nearly a quarter thought they could catch one.

Even on Burns Night, getting Americans to eat the most Scottish of meals is no easy task, explains Paisley-born Jim Short, 76, who attends a Burns Supper in LaGrange, Georgia, organised by The Order of the Tartan, a local Scottish heritage society.

The majority of attendees are US-born, however, and out of deference to their palates, haggis is not served as the main course.

"We're lucky if some of them take more than a mouthful," laments Short, who once had three cans of tinned haggis confiscated by customs officials on arrival at Atlanta's Hartsfield-Jackson airport.

After the US-manufactured pudding is piped in and the Address is delivered, a helping is left in the centre of each table, for those brave enough to nibble on crackers. The main course might be beef, or cottage pie.

Of course, American culinary culture is far removed from Scotland's.

Haggis, a traditional Scottish sausage Sheep's stomach stuffed with diced sheep's liver, lungs and heart, oatmeal, onion, suet and seasoning

Vegetarian versions can be made with mushrooms or beans

Served with neeps 'n' tatties - mashed swede and potatoes - and whisky on Burns Night Haggis, clapshot and whisky sauce More haggis recipes by BBC chefs

Jo Macsween, director of Edinburgh-based haggis manufacturer Macsween, observes that the US does not share the tradition of "nose to tail" cooking, in which no part of the animal is wasted.

"I think Americans tend to be bit fussier about their meat - they'd rather have steak and prime cuts," says Macsween, who briefly lived in Boston, Massachusetts, after leaving university.

But she notes that US visitors invariably sample haggis on trips to Scotland and are usually pleasantly surprised at the result.

For Massie, it is a "grotesque double standard" that French Andouille sausage - which traditionally comprises the intestines of a pig - is permitted on American shores and afforded culinary respectability while haggis is not.

He believes the answer lies in liberating haggis from the confines of the Burns Supper and celebrating it as a delicacy in its own right.

"Its qualities can be overshadowed by the pomp and ceremony of the event," he says. "But actually, it's a very fine dish."

If all else fails, he suggests, "it shouldn't be too difficult to organise a cross-border smuggling operation" to bring the authentic product to US palates.

It may be more difficult, however, to help Americans love what Burns fondly termed the "gushing entrails" of the indigenous haggis.

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