Readers with a delicate constitution may find this book hard to swallow. It is not a restaurant guide, nor a volume on cooking. There are few descriptions of food, and not a single recipe. Do not look in these pages for reflections on great cuisine, or some just slice of wisdom on how to lose weight. This is a book about dining out, which begins with a reservation. It will not guarantee a table anywhere, much less a warm reception:

The restaurant business is more accurately described as a racket.

No revelation, that reservation is made – or muttered – whenever humans eat in public. Until quite recently, most normal people were reluctant to dress up, endure rude service and pay for food that was sometimes fatal and always expensive. There was probably a difference between the scams of the culinary cartel and the antics of real-life criminals, but no one was quite sure what it was, so everyone practised caution. “In restaurants,” says the novelist Martin Amis, “my father always wore an air of vigilance, as if in expectation of being patronised, stiffed, neglected or regaled by pretension.”

Today, dining out is a part of the life well lived. Restaurants are a destination, and we go in greater numbers than ever before. Encouraged to believe that no one has time to cook anymore, we fling ourselves at much-hyped chefs like a nation of hungry sheep. The blame, or the credit, does not lie solely with the media. We read more menus than recipes for many reasons, including the most banal: the demise of the traditional family, sexual liberation, more disposable income, snobbery, cheap air fares and the eclecticism that travel encourages. This is reflected in the sort of menus that offer smoked eel, Pad Thai and pepper ice cream. If that strikes you as a ridiculous mixture, you are not conceited enough to work in a professional kitchen, where the vile frequently masquerades as the exotic.

The burgeoning popularity of restaurants is a largely positive phenomenon. However, when they’re not just bemused, diners have a right to feel short-changed. Some restaurants are owned by thieves. Others are staffed by the criminally insane. All are reviewed by the sort of people who believe that no good meal is complete without a sorbet to cleanse the palate, and that Michelin stars keep the sky from falling down.

Later in this book I will look at the history of restaurant criticism, as well as some of the loudest voices in the racket today. Many have catching up to do. In Britain this means admitting that in culinary terms, London is another country. In America it means acknowledging that people dine out for many reasons: often, the food is incidental. And while newspapers focus on celebrity chefs, the real news in restaurants is at the other end of the market. Slapdash dining is what most punters want, which explains the rise of the dreaded kebab and the all-weather smile of a clown called Ronald McDonald.

As a restaurant critic, I am conscious of the position that colleagues now occupy in the culture. There are 40,000 restaurants in the United Kingdom. By the year 2010, half of all meals will be eaten away from the home. As consumers choose to dine out more often, the power of the press increases. In a 2005 survey on toptable.co.uk, 84% of respondents said, “reading a restaurant critic’s opinion would sway my decision to go to a restaurant.” Like politicians’ wives – unaccountable, powerful and usually up to mischief – reviewers have almost emerged by stealth. Some are invidious, many are pompous, and the job itself is not exactly onerous. Yet the best provide a public service.

In an age that feels almost fatally harried, good restaurants are where we relax in the company of people we like, where we remove ourselves from what goes on outside, elsewhere, somewhere not this civil. They are where we try new flavours, where we feel pampered or rewarded, and where we connect with people who are important to us. Under the right circumstances – and pointed in the right direction – the dining room is a place in which we become some slightly more attractive version of ourselves.

In addition to exploring how humans eat in public, Kitchen Con contains the confession of a small-town hack. Social history gives way, in parts, to memoir, that generous threat of a word – for this is memoir in the same way that Michael Moore and Ingmar Bergman are both serious filmmakers. The journey described is not typical, nor in any way laudable, and my view of lunch may be no clearer than your own. I grew up in Ireland, where my parents owned a famous restaurant, at a time when the recipe for mashed potatoes was still regarded as a national treasure. To this day, there is only one way in which I might be described as a culinary expert. I love spaghetti westerns.

You may well wonder why this is my first exposure. You may also discover how easy it is to become a judge of dinner. All you need is a pen, some paper and an appetite. Restaurants are in business to offer a service, and if you pay for that service you’re entitled to have an opinion. As long as you don’t break the law you are also free to share it. These are the rules of the new restaurant criticism, and of something grander still. Democracy. Kitchen Con tries to determine what this means for customer, critic and chef.

Finally, this book observes a breathtaking display of consumer democracy. Few commentators have championed the event in print, and with good reason: it poses an unprecedented threat to critic and chef alike. They are the people who traditionally decide what good taste means. But the rise of the Internet is changing the game forever, as thousands of sites emerge to lend all diners a voice. In other words, the customer is becoming the critic.

That knowledge is exciting. Like dinner tonight it comes at a price, and prompts new speculation. Is it fair to feast while others starve? Why are waiters like cocaine dealers? Can one ever trust a guidebook? Is it lawful to leave a restaurant without paying? And which fool picked that wallpaper?

To answer those questions, join me for dinner in London, Paris and New York. Along the way we shall meet great guardians of gastronomy, each choking on a slab of foie gras. A few may survive, but it won’t be pretty – and where we’re going, those Michelin stars mean nothing. It’s not that sort of place.

Welcome to the 21st Century Dining Room.