Tricks of the Restaurant Trade - Season 4

Simon enters the secretive world of research and development at Starbucks. Adam explores the latest trend in bottled water, but would anyone spend £100 a litre? Plus: cocktails and restaurant apps.

Simon Rimmer unlocks the science of what happens to our taste buds during air travel and discovers why the Bloody Mary is a popular in-flight drink. The British Airways development team reveal how they adapt their cooking for high altitudes and Simon discovers that we lose 30% of our ability to taste when we fly. Food critic Lisa Markwell joins Simon for a taste test at 35,000 feet. Meanwhile, Sophie Morgan investigates the food on offer at motorway service stations and how prices compare to the high street. And Adam Pearson explores one of the latest food trends: mash-ups or hybrids. What do diners make of sushi burgers or cronuts?

With UK restaurants handing out discounts worth £35 million a year, Simon Rimmer calls on expert help to reveal how it's possible to eat out at a fraction of the price. He tracks down the best offers and proves that there are plenty of big chains willing to give away food and drink for free. Sophie Morgan and food critic Lisa Markwell visit a luxury hotel to find out how fine dining meals can be affordable. And - fat, skinny, skin-on - we all have strong opinions about chips. But which are the healthiest? Sophie finds out.

This episode investigates how health has become a £5 billion trend on the high street. Almost nine out of ten people say they are willing to pay more for healthy choices so Sophie Morgan investigates how the big brands are interpreting this. Simon Rimmer looks at a surprising health makeover: the great British pie. He heads to Melton Mowbray to see how this traditional favourite is being challenged by new vegan and vegetarian varieties. Another big winner riding the health trend is the growing juice bar market. Sophie and nutritionist Amanda Ursell discover surprising levels of sugar, which run contrary to the healthy sounding names of the drinks. And Adam Pearson reveals the common psychological trick used on restaurant menus to make diners spend more.

Sophie Morgan discovers how restaurants go to great lengths to ensure that their customers' Instagram pictures do their dishes justice. Simon Rimmer talks to TripAdvisor about its ability to make or break a restaurant business and meets the owner of a small crêperie that was overrun when it was rated number one in London. And, with social media helping to drive UK interest in American barbecue, Simon visits a popular UK-wide chain where unfashionable cuts of meat are transformed. Meanwhile, Seyi Rhodes takes to the high street to see if he can revive a meat dish that has fallen out of favour.

Simon Rimmer explores how food is transforming our lifestyle, with a quarter of us regularly eating out for breakfast. Sophie Morgan asks whether the nation's favourite drink, tea, could challenge the booming coffee sales on the high street. Simon visits the award-winning packaging company whose innovations have allowed high street chains to offer delivery to our homes for the first time. Sophie investigates what restaurants are doing to cut salt levels, as we're still consuming a third more than we should, and reveals the surprising amounts of salt in some desserts. Plus: the psychological tricks to make customers spend more in restaurants, from lighting to aroma and even seat padding.