Here at OFM we hesitate before singing our own praises - though obviously not for that long. Today, as we launch our fifth annual food awards, we are able to look back with a great deal of pride at four years of terrific winners. The much-coveted gongs that we hand out - the vast majority of which are voted for by you the readers - have not merely awarded excellence. They have created a riveting picture of this country's ever-changing food culture and, at times, even moved the debate forward. Often, we can rely on you lot to spot things before the experts have done so.

We've got proof of that with our very first high-profile award back in 2004 - that for best restaurant. When we counted that year's votes there was one clear winner: Heston Blumenthal's Fat Duck in Bray. Today that sounds like a no-brainer. Of course it would be voted best restaurant. But back in 2004 Blumenthal's then two-Michelin star restaurant was more of a cult than a phenomenon. Die-hard fans went there for his red-cabbage gazpacho with grain-mustard ice cream, his crab biscuit with foie gras and his smokey-bacon ice cream.

But, as Heston recalls, they didn't necessarily go there in vast numbers. 'This might sound a bit dramatic but the OFM award really was the first extraordinary moment in a week that changed my life,' he says. The day we told his assistant the news, ahead of the official announcement, Heston was flying to Madrid to take part in a prestigious conference for cutting-edge chefs. 'As I got on the plane on the Monday I didn't know how we were going to pay the wages bill on the Friday,' he says. 'We didn't have enough money and my house was already hugely mortgaged. My wife didn't even know how drastic the situation was.'

As he arrived at his hotel he received a message telling him to call the Fat Duck and, when he did so, he was told that OFM's readers had decided his restaurant was the best in Britain. 'It really was an amazing moment,' he says. And a prophetic one. It was another two days before Michelin announced that the Fat Duck had also been awarded its third Michelin star, the highest rating possible. 'The night we won the third star we had only six people booked into the restaurant,' Heston says.

Today it's rather different. You can only book two months in advance at the Fat Duck, and all the tables for each new day are gone within half an hour of the phone lines opening. At the same time Heston has become a serious star. His BBC2 series In Search of Perfection, in which he set out to create the perfect version of classic dishes, was a huge hit and the book that came with it a bestseller. A second series, in which he attempts everything from the trifle to the hamburger, from risotto to chicken-tikka masala, has just launched on BBC2 and he'll also be doing a Christmas special.

If the past four years have been good for Heston, he also thinks they've been pretty damn good for British food in general. 'I think one of the biggest things that's happened is the arrival of regional suppliers,' he says, 'People who aren't just slaving away in anonymity but who can now be recognised by national awards like yours.' Naturally, we couldn't agree more. 'But what's also interesting is the way all the really cutting-edge restaurants, the really interesting ones, are no longer to be found in London but spread out across the country.' He's not wrong. The year after you gave the top award to the Fat Duck, you gave it to Anthony's in Leeds, where a terrifyingly young chef called Anthony Flinn, who had learnt his craft at the famed El Bulli, made white onion risotto topped with parmesan 'air', and savoury trifles. Today Anthony's is going strong, and the same team now runs a couple of other ventures in the city. His award was proof, if proof were needed, that you are a thoroughly adventurous lot when it comes to the really important decisions, like where to have lunch.

Though we're sure he's too polite to admit it, one of the pleasures in winning for Flinn and his team must have been whom he beat: Gordon Ramsay, whose flagship restaurant in Chelsea came second. Not that Gordon has much to complain about where the OFM awards are concerned. Indeed it's fair to say that you could track his career through the various appearances he has made in our shortlists. That second year, for example, he was also a runner-up in the best food television category with Hell's Kitchen. In 2006, he made it into the commended list with Kitchen Nightmares. In 2007, he collected the number-one spot for The F-Word. Gordon is clear that this is big stuff. 'Winning The Observer Food Monthly award for Best TV Show meant a huge amount to everyone involved in the making of the series,' he says now, 'because the readers of Observer Food Monthly have to be the most discerning and food-savvy critics of all.'

The other huge name in British food who cannot be ignored - and who certainly hasn't been - is Jamie Oliver. In 2004 his TV series, Jamie's Kitchen, about his attempt to train a bunch of misfits to be chefs easily took the number-one spot in the best TV show category. But 2006 was the year that really mattered. By the time the specialist judges sat down to adjudicate we already knew that his series Jamie's School Dinners had again won the best-television category (and that his book, Jamie's Italy, had come runner-up in the book category). But we were clear that wasn't going to be enough. Too much food journalism - television, radio or print - is merely about a certain kind of self-indulgence. With Jamie's School Dinners, Oliver had done something far greater than that, giving huge impetus to a campaign over the dismal quality of school meals. He even forced the government to cough up serious money to do something about it - years ahead of when they might otherwise have done so. He had used his celebrity to leverage a major political campaign.

The problem was that we didn't feel he qualified for the lifetime achievement award, given that he was still so bloody young. And so, after much discussion, we decided to create a category just for him: the Outstanding Achievement award, which we thought summed it up. 'It was such an honour to get the award and at the time it was a much-needed pat on the back because school dinners had been such hard work,' he says now. 'I've always been passionate about my work and about food in general but I'm also passionate about the food industry and so to get an award from people who know their food was very special.'

We're glad he thought so. As to the debate on school dinners, Jamie thinks it's far from over. 'There are some good things going on up and down the country and there are some bad things. When I started the project, I always thought it would take up to 10 years to get everything working - dinner ladies trained, new kitchens put in, kids and parents happy - and in many schools things are on track. It's where councils and head teachers and dinner ladies and parents all pull together to make it work that the successes happen. But there is still a long, long way to go and much more work that needs to be put in.'

Then again, here at OFM we were across the debate on school meals long before Jamie took to our screens to campaign for them. In our very first awards in 2004 we handed our Hall of Fame award to a then-unknown dinner lady called Jeanette Orrery. Jeanette had set about revolutionising school meals at St Peter's in East Bridgford, Nottinghamshire, by throwing out the processed mush and bringing in locally sourced, fresh ingredients to be cooked on site. Back in 2004 that really was revolutionary, and certainly something that deserved to be recognised. 'The OFM award is the one people mention time and again whenever I go to conferences,' Jeanette says - and she goes to conferences an awful lot. She is constantly criss-crossing the country, spreading the doctrine of quality school meals. Indeed, three years ago she realised she was in such demand that, with huge regret, she had to leave St Peter's to work on bigger projects. 'It was a terrible wrench but I knew it was the thing to do.'

Today she is the school-meals policy adviser for the Food for Life project, a £17-million scheme run under the auspices of the Soil Association. She has overseen the opening of two training kitchens for dinner ladies all over the country and has written not one but two very successful cookbooks. 'The cookbooks were a direct result of the OFM awards,' Jeanette says.

Over the years she has been joined in the Hall of Fame by a succession of extraordinary individuals whose influence on the debate about what and how we eat is immeasurable. There's the food contamination guru Professor Hugh Pennington (very busy, right now, giving expert opinion on both the foot-and-mouth and the bluetongue outbreaks); there's Patrick Holden of the Soil Association; and, this year, Professor Tim Lang, the man who invented the term 'food miles'.

Jeanette, though, has a special place in our hearts here at OFM because she has also sat on our judging panel a few times. We couldn't have been more delighted to have her, not least because some of the decisions we've had to take have been very tough indeed, especially in the category of best food producer, which just gets harder every year. The problem isn't finding someone to give the award to. It's sorting through the literally hundreds of small producers, doing fantastic work to bring niche and home-made products to an eager public, and finding one that stands out from all the rest. As Heston says, there is now serious quality out there. Over the years we have given the nod to the remarkable meat company, the Ginger Pig, to Secretts Farm which has done such important work rearing rare and unusual salad leaves and herbs, and Falko Burkert. We think he's one of the best bakers in Britain, and we'll punch anyone who argues with us.

Likewise, you have voted for a series of outstanding retailers, the continuing success of whom can only give succour to those who fear the supermarkets are taking over. From the entirety of Borough Market, to the cheese fetishist wonderland that is La Fromagerie, from the Spanish food experts Brindisa to the organics trailblazers at Riverford in Devon, you have led us to some of the very finest ingredients available in Britain today.

But perhaps the most successful of the lot from the producer or retailer categories, is our first winner, L'Artisan du Chocolat. Back in 2004, they were a tiny producer with a stall in Borough Market and a shop just finding its feet in Chelsea. Much of their trade came from supplying restaurants, including OFM awardwinners like Gordon Ramsay and Heston Blumenthal. Today their turnover has risen fourfold and they have had to move production to a much bigger site to cope with demand. 'The OFM award was hugely important, and not just because it made us feel good about ourselves,' says Gerard Coleman, the softly spoken Irishman behind the phenomenon that is L'Artisan. 'It opened the eyes of the public to the fact that there was somebody in Britain making quality chocolates that didn't simply copy what was coming out of Belgium and France. It brought us serious customers.'

Among those has been first Waitrose and now the high-street institution which is Marks & Spencer. 'We're doing a product for them for the Christmas market, but it will be found in the chiller cabinets. It will have a shorter shelf-life but it will be of serious quality.' And their bestseller? All these years on it's still the liquid salt caramels, he says, just as it was at the beginning. And rightly so. They are to die for.

It's not the only thing that hasn't changed. There is one - and just one - category which has produced exactly the same winner, every single year, and that's best book. The books have changed, of course, but the author hasn't. His name is Nigel Slater, and you clearly think he's as great as we do. Whether it's for his gloriously hungry memoir Toast, or cookbooks like Appetite or the Kitchen Diaries, you cannot get enough of him. 'The Observer awards came along like a breath of fresh air,' he says. 'Getting an award via a public vote like this means so much. The truth is that I never, ever expect to win anything, so I'm always surprised, delighted, and very grateful if I do. Even more surprised considering my books are not exactly what you could call mainstream.' Will Nigel make it five in a row this time round, with Eating for England? We have no idea, because it's up to you. It's time, we think, for you all to get voting.

· This article was amended on October 19 2007. The article above is about the 2008 food awards, not 2007. This has been corrected.