A new book by an industry insider may change the way you look at eating out altogether - Restaurant Babylon by Imogen Edwards-Jones lifts the lid on shocking behind the scenes secrets.

The revelations include certain top restaurants using a marking system to identify difficult customers, and the tricks used to flog off slightly elderly food by marking it as a special.

The insider information has come from Britain's top restaurant owners, chefs and sommeliers, says the Daily Telegraph, and is anonymous.

Apart from superb presentation, you'll also get a side order of the chef's spit - as one spoon is used to taste all dishes.

Miss Edwards-Jones said: "The chef has tasted and sampled, picked and tweaked, gobbed and re-gobbed into everything on your plate.

"How else was that little violet flower petal ever to stay on the plate?’

However, not all of the secrets will put you off dining out, instead, they are just handy tips. Read on to see which 20 tips and secrets made the book.

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  • <em>Scared to look like cheapskates, customers always order the second cheapest bottle on the wine list, so restaurants give it a higher mark up. </em>

  • <em>Restaurants hate email bookings as they are more likely to be a no-show and tend to be computer-literate and likely to review or blog about it online afterwards.</em>

  • <em>All restaurant food will contain the chef’s saliva, as the same spoon is used to sample dishes. When presenting food they also use the “lick and stick” method to keep things in place. </em>

  • <em>Sometimes the 'specials' are only 'special' because restaurants are desperate to get rid of them. </em>

  • Grilled steak and beef gravy - delicious!

    Close-up of a juicy, succulent grilled steak accompanied by glazed carrots and beef gravy - or jus - to make a delicious, luxury meal,

  • <em>Staff, ingredients and prep time have to be factored into the cost of a dish, with a pizza the quickest way to get ripped off with a huge mark up. </em>

  • <em>Nothing matters more than getting a Michelin star. One star puts them on the map, two stars means the phone never stops ringing and three stars means they can charge anything. </em>

  • <em>Restaurants know women are easier to sell to and they've committed to sit there longer, so there's at least a 'one to share' pudding to be slotted in there. </em>

  • <em>The business lunch is a restaurant's bread and butter but as everyone wants to be in at 1pm and out by 2.30 the waiter will dither over the menu so you do not notice the delays. </em>

  • <em>Restaurants love side dishes as much as they love a vegetarian option or a bowl of soup as they cost pennies and can be sold for several pounds. </em>

  • <em>Restaurants will re-use your half-drunk bottle of wine, serving it by the glass the next day.</em>

  • <em>Seating the clientele is an art form, with VIPs and the pretty girls at the front, and couples put at the back close to the fat Russian men. Japanese businessmen come at the bottom of the pecking order. </em>

  • <em>After it became more socially acceptable to order tap water, many restaurants introduced a £2.50 a head cover charge for you just to sit there, or started charging for the bread. </em>

  • <em>Menus are designed for women, who are much more likely to book the lunch or night, and whose partners will follow. </em>

  • <em>Don’t drink the wine if it is laid on its side under spotlights, as it has been stewing for months, if not years. </em>

  • <em>Restaurants often keep some choice wines out on show and a few less choice ones below eye-level at the bar, so you might not be getting the house wine you thought. </em>

  • <em>Nobody ever checks their bill properly, and the restaurant could, and sometimes do, add extra items. </em>

  • <em>Drugs use is rife amongst workers, mainly cocaine. </em>

  • <em>Top restaurants keep a little black book of incidents and some of the more exclusive will put a black mark against the names of rude customers. </em>

  • <em>Theft is common, and some is accepted including taking the odd bottle of wine. But others examples of theft, including stealing money, are not accepted. </em>

Restaurant Babylon by Imogen Edwards-Jones is priced £14.99.

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