Soon after starting research for his book on the multicultural history of food, Panikos Panayi found his name on a rightwing website, under the heading "Know your enemy". A serious, slightly diffident professor of European history at De Montfort University, he had committed a supposedly hostile act by raising the possibility that fish and chips may not be entirely British. Frying was a typically Jewish way of eating fish, he had suggested, while chips were probably pre-dated by French pommes frites. The idea proved so controversial that it prompted newspaper headlines. Some interpreted the attempt to deconstruct a British national dish as akin to attacking the nation itself.

It was a clear demonstration of how intimately connected people perceive food and national identity to be. But according to Panayi, this perception is wrong. He argues that dishes don't have a nationality. Examine any one of them closely and you are likely to find influences from all over the world, not only in the ingredients but in the way they are served and eaten. Rather than being a symbol of nationality, he says, "what people eat is a really important symbol of the integration and assimilation process". In his view, it is impossible to understand what British food, and especially eating out in Britain, is about without also studying immigration.

Ice cream

Take ice-cream. While this did not exist in Britain until brought in during the late 19th century by Italians, who dominated its sale on the street for the next 100 years, its transformation into Mr Whippy cones and the solid blocks of Lyons Maid was uniquely British. The firm J Lyons and Co, incidentally, was Jewish.

Then there's the restaurant. This concept originated in post-revolutionary Paris and arrived in Britain only in the late Victorian period - so its existence involved British adaptation of a French idea. The recognised order of the menu - soup, fish, entree, roast, dessert - was known as à la Russe because it was believed to imitate the way the tsars ate. At that time, only the higher sections of society would use restaurants, but lower classes would often eat out in other ways, such as buying an ice cream or fish and chips on the street. Quite apart from the origins of the food, the people who served it were usually migrants. In fact, foreigners had become so dominant in the restaurant trade that a Loyal British Waiters Society was set up in 1910 to protect "the interests of British waiters as a class".

After the second world war, all sections of British society developed a taste for "foreign" foods, such as curries, pizzas and Chinese dishes, frequenting places originally established by migrants to serve their own communities. But this food became increasingly Anglicised, just as French haute cuisine had been during the 19th century. Again, the story is one of assimilation.

So for Panayi, "saying foods have a nationality is extremely bizarre". At best, it is sometimes possible to say that foods are regional, with wheat changing to rice between regions in India, for example. But even this can only be taken so far. He takes from his shelves a book on British cuisine - the kind of concept that irritates him - which is divided into regions. The section on south-east England is written by Gary Rhodes and Atul Kochhar. "I'm not sure what that says apart from that curry has become part of 'south-east English cuisine', although curry is also part of Midlands cuisine, since baltis are supposed to come from Birmingham," he says.

Panayi's book, Spicing up Britain, is a detailed survey of British eating habits since 1850 rather than any kind of polemic. In his research, he used cookbooks, which, he says, "have the same role for culinary development as political ideology has for the evolution of states", along with Mass Observation reports, oral accounts and secondary material.

It argues that there was a noticeable change after 1945 when, largely thanks to growing prosperity and clever marketing, food came to be associated with particular nations. Before then, for most people, it was just food - and their main concern was getting enough of it. The book acknowledges that even if food has no nationality, it is still a useful way of exploring what is going on in a nation. "It is very much a history of one way of interpreting multicultural Britain," says Panayi, "the way in which immigration has changed Britain over the past 160 years, and especially since the second world war."

He argues that postwar immigration was very different from that in the 19th century because it was on a larger scale, involved different countries of origin, and migrants were arriving in parts of Britain that previously had little experience of outsiders.

The results of this became apparent through three phases of foreign influence on domestic food consumption after 1945: austerity, prosperity and big business. Until the 1950s, rationing still dominated what people ate, limiting choice and forcing people to make do. This led to a relatively bland and monotonous diet, which made the introduction of new tastes over the next few decades all the more exciting.

Culinary revolution

He describes the years from the late 1950s to the end of the 1970s as a culinary revolution, led by the cookery writer Elizabeth David, its "Voltaire, or perhaps even ... Marx". It was aided by advances in technology, a new spirit of entrepreneurialism, increased prosperity and immigration. The final phase from the 1980s to the beginning of the 21st century was dominated by choice, and the efforts of business to supply it. Multinationals and supermarkets began to produce both ingredients and ready meals mirroring what was on offer in foreign-run restaurants - and in the process moved further away from the foods that members of ethnic minorities initially consumed.

For Panayi, who has been at De Montfort since 1990, the book marks a similar journey. In one sense, it is a return to culinary origins that he seemed to have left far behind. His father was a pastry cook, apprenticed from the age of 12 to an uncle who owned the most famous patisserie in Nicosia, in Cyprus. Panayi senior travelled to England to seek his fortune and worked for a number of Greek Cypriots in London, specialising in wedding cakes.

Panayi junior, by contrast, chose to study history at the then Polytechnic of North London, followed by a PhD at Sheffield on Germans in Britain during the first world war. As well as a number of books on Germany and German immigrants to Britain, he has written about racial violence, the history of European minorities, and the impact of immigration. Last year, he published a book on the experience of Osnabruck before, during and after Nazi rule.

He says his father never wanted him to follow in his footsteps: "He thought it was hard work." But the idea that he might become an academic had never entered his mind. "It was just inconceivable for a Greek Cypriot growing up in Britain to get to be an academic," says Panayi. "From pastry chef to professor was quite a drastic leap."

At first, it wasn't an easy one either. Panayi was unemployed for nearly a year after securing his PhD, in spite of watching many of his peers secure posts. "The historical profession, especially 25 years ago, was overwhelmingly white," he says. "I think I was just too strange." He recalls one interview with a professor who couldn't understand why, since he was a Greek Cypriot, he hadn't chosen to study the history of Cyprus. "All academics struggle, but I had done an awful lot of things," he says. "I still resent all that."

He says that things have improved, thanks to increasing academic globalisation and pressure to recruit the best, regardless of background or nationality. The publisher Longman has recently commissioned him to write a history of immigration - a sign, he suggests, that immigration issues are also becoming more interesting to students. Meanwhile, he is also working on a short history of fish and chips, a request from publishers well aware of the interest the topic has already generated. While he is not yet a food historian, Panayi says, he may yet find himself becoming one.

In Spicing Up Britain, he recalls how he would reject his parents' meals of pulses flavoured with olive oil and lemon juice in favour of fish fingers and baked beans. Later, in his 20s, while his parents cooked from scratch every day and never managed to understand the British obsession with processed food, he embraced ready meals, although he did learn to cook once he left home. His book is noticeably devoid of the sensations involved in tasting and handling food, preferring to concentrate on analyses of surveys and texts. But he claims that, as a result of researching it, his attitude towards food has changed and his interest has been rekindled. Now he usually cooks all his meals, and has even started growing his own vegetables. And, being married to an Indian Sikh, his diet is thoroughly multicultural.

So much for his eating habits, but what about his identity? How would he describe himself - living in Leicester, born in London, to Greek Cypriot parents, married to an Indian woman? Panayi looks baffled. "I'm British," he begins doubtfully. What about European? "Yes," he agrees. "European is nice. That describes everything."

Curriculum vitae

Age 45

Job Professor of European History, De Montfort University

Books Spicing Up Britain: The Multicultural History of British Food; Life and Death in a German Town: Osnabruck from the Weimar Republic to World War Two and Beyond; Outsiders: A History of European Minorities

Likes Bach, Chelsea FC, gardening, Germany

Dislikes Incompetence, discrimination, processed foods in restaurants

Married no children