CLARISSA Dickson Wright suspects she was Chinese in a former life. "My comfort food is Chinese. I like all these strange, exotic, glutinous things that they eat, like duck's webs and tripe, and cockscomb. Did you know that Catherine de Medici couldn't consummate her wedding to Henri II because she was ill from gorging on cockscombs stuffed with artichoke hearts?"
This is quintessential Dickson Wright – sparky, provocative and informative in a single go. Never mind that when curiosity sends me to Google, I discover that while she's remembered the recipe perfectly, in fact, Catherine poisoned herself at the wedding of Mademoiselle de Martigues to the Marquis de Lomenie. I score Dickson Wright two out of three points, with a bonus for holding me rapt.
She is the best of conversationalists: full of ideas, passionate, articulate, entertaining, and surprisingly low-key, though not so mellow that she won't snarl when her dander's up. She very nearly gets up to complain to a pair of overly noisy breakfasters at Valvona & Crolla on the morning that we meet to talk about her appearance on BBC2's Great British Food Revival, in which she's championing the British Lop pig.
"The British Lop is rarer than the Giant Panda. It looks like a pig a child would draw – pink with floppy ears. They're absolutely delicious. Because they weren't a tallow pig, but a meat pig, they don't have huge amounts of fat and it's nicely balanced throughout."
Once upon a time Britain had hundreds of different types of pig. The tallow breeds were used for, among other things, making candles, soap and cooking fat. Their eradication may, Dickson Wright reckons, be largely due to the popularisation of electricity. "And also, probably, margarine. Nearly all of the tallow pigs went extinct, something like 50 or 60 breeds in the British Isles. These old breeds taste so much better. They bear no resemblance to the stuff that tastes of polystyrene that you buy in your average supermarket. By all means, buy old breed British pork in preference to modern, horrid numbered pigs, which, to my mind, have single-handedly destroyed the pork industry in Britain, but what I'm actually trying to save is the British Lop."
The programme filmed British Lops being bred in Rutland, at Jan McCourt's farm, Northfield. "He is the only person outside Cornwall with a substantial herd. If you read Margaret Visser's book, Much Depends on Dinner, the underlying theme is the attempt of various countries, the US in particular, to reduce everything to just one strain, whether it's corn or potatoes or pigs. Quite apart from the lack of flavour that that will engender, it's incredibly risky. What happens if you get a blight that attacks that particular strain?"
I mention a recent piece in The Atlantic Monthly that accuses foodies of being elitist snobs. She's having none of it. "The poor have always eaten badly, but they ate a lot better before the Industrial Revolution and the coming of cheap supermarket food. I was just reading George Orwell's The Road to Wigan Pier, and what working classes ate in the 1930s – compare that with William Cobbett, 120 years earlier, when people were still making their own beer and baking their own bread in the country and going out into the hedgerows and gathering food. The difference is amazing. I am quite certain that the endemic bad health in the poor comes from centuries of bad diet."
She argues that it's no more expensive to buy good quality food because you waste less. "When you cook cheap bacon, all that white muck that comes out of it, that's all the water and other stuff that has been pumped into it to make it weigh more. Whereas if you cook dry-cured bacon, which may have cost a bit more, what you've got is the same amount of bacon that you started with. Any fat that comes off it you can make oatcakes with, or something.
"I'm a great champion of farmers' markets. I'm patron of Farmers Markets in England and president in Scotland. The people shopping at them are not just the professional classes. People have realised that you might pay a little bit more than you do in the supermarket, but if you buy three pounds of meat in the supermarket and cook it, you end up with two-and-a-half pounds of meat, because supermarkets don't hang their meat. If you buy three pounds of meat in a butcher's or at a farmer's market, you'll end up with three pounds of meat. So you have to calculate the shrinkage."
She advocates eating less of higher quality food. "We eat far too much meat, and bad quality meat at that. I love meat, but even I don't feel the need to eat it every day, and certainly not twice a day. You look at people who go into cheap supermarkets and buy six chicken legs – I expect they're all off one chicken! – for 99p. They're not getting any nutrition, it tastes disgusting and if they multiplied their money just the once, they'd get much better food."
I despair of Scotland sometimes, I tell her. There's so much great natural produce, and so much utterly dreadful food. I still cannot understand what goes wrong between the time it's picked, killed, or caught, and when it hits the table. Laughing, she suggests, "If you got rid of the cigarette and the deep fat fryer, the Scots would probably live forever. The whisky's supposed to be good for you – unless you drink it in the quantities that I did! It's a chicken and egg thing with exports, though. Is so much of our produce exported because the Scots won't buy it, or is it exported because you get more money for it?"
On the issue of Scottish independence she says: "I think it's a totally mad idea, but I often wonder if Alex Salmond actually wants it. Every Scotsman dreams of an independent Scotland, but let's face it, Scotland was sold for 40,000 guineas by the Hamiltons. Scotland couldn't afford to go independent, especially now with the oil and the gas running out.
"Having said that, I actually think Salmond is the most charismatic politician in British politics. And considering he's been running a minority government for the past four years, he hasn't half done a bad job. Even though I'm not an SNP supporter, I think it's good that they broke the death grip that Labour had on Scotland, not just because it was Labour, but because I don't think anyone should have a right to rule for 40 years. You begin thinking that you can get away with anything."
She's spoken highly of David Cameron in the past, once saying that he "understood the countryside". Does she still feel that way, after the rigmarole about selling off the forests? "He's not selling off the countryside. What he's actually talking about is selling off the commercial aspects of the national forest. Forests have to be managed.
I was always amazed, when we did Clarissa and the Countryman, that people – journalists, presenters, whatever – thought that trees grew themselves. Managing forests is an expensive occupation, and commercial forests aren't the places where you want to go and walk, because they're all conifers. Nothing lives there. They're deeply boring. It's really quite a small amount of forestry still owned by the government. People have been selling it off since Elizabeth I.
"I have time for David Cameron, certainly on food. This is a man who until quite recently grew his own vegetables. He wasn't doing it for the camera."
She made a video for the Conservatives about food labelling, which was launched at the last AGM of the National Farmers Union. In it, she takes issue with Section 36 of the Trade Descriptions act. "It says that a product may be named as being of the country where something was last done to it. So you can get Chilean salmon, smoked in Italy, sliced in Scotland – and it's Scottish Smoked Salmon."
What recourse do consumers have if they want to eat local? "Go to a butcher or a fishmonger or a greengrocer and ask where the food came from. You have a right to know. I'm constantly appalled at how shocked people are when I speak about this. People are trying to buy British and they go into supermarket and it says Scottish beef, and they think they're doing the right thing."
But don't typecast her as a Conservative, she warns. "On certain issues the only people I identify at all with in politics are the Scottish Socialists. Their attitude toward addiction and alcoholism especially. Do you know that if you're on the dole you get 40 extra a week if you're an alcoholic or an addict to pay for your habit? That's shocking! God, I'd never have stopped drinking," she laughs, "except that I wasn't on the dole. It's a world turned upside down at the moment."
I could sit here all day talking, but there are others with claims to her time. Still, there'll be a second coming of Dickson Wright this autumn, when Random House publishes her History of English Food. It begins with the Second Crusade and continues into the present day. Maddeningly, she's keeping mum about the project, and instead of spilling any secrets, suggests that I interview her again when it's out. I do, however, discover we share a deep affection for Eleanor of Aquitaine.
"She established the wine trade between Britain and Bordeaux. A great heroine. That woman built the first refuge for battered wives at Frontevraud Abbey (in the Loire valley]. And if she hadn't gone on the Second Crusade, it would have taken a lot longer for all those spices and sugars to get here."
We began with a queen, and it's fitting to end with one – though by now you'll realise I am referring to a certain queen of cookery.
• Clarissa Dickson Wright can be seen on the Great British Food Revival on BBC2 on 24 March, 7pm. The book accompanying the series is published by Weidenfeld & Nicolson, 20