Dan Coudreaut secured one of the most influential jobs in the restaurant industry the old-fashioned way, by working his way up from the bottom. He began his career washing dishes in a local restaurant when he was 14 and eventually graduated to the kitchens of national chains, including a Four Seasons hotel.

These days, Coudreaut is at an even better-known brand - McDonald’s, the hamburger giant. As the man who runs the company’s test kitchen, he has a big say in the eating habits of millions of people all over the world.

Coudreaut, who turns 43 this Saturday, joined McDonald’s in 2004, after stints at the Four Seasons in Dallas, where he was responsible for prepared food at all the dining outlets in the hotel, and Metromedia, a steakhouse operator, where he was director of product development. In 1995 he graduated top of the class at the Culinary Institute of America.

At McDonald’s, he has the title of director of culinary innovation. It is Coudreaut’s job to come up with new products to supplement the company’s core range - the Big Macs, cheeseburgers, fries and so on that account for about 70% of American sales.

He said that other chefs were often surprised that someone would choose to work for a fast-food company rather than a traditional restaurant. “But when I start talking about the fact that I [affect the lives of] 25m people, they start asking me how I got the job,” he said.

Coudreaut has endeared himself to his employers with some notable successes, such as the chicken snack wrap and the southwestern salad; the latter incorporated edamame - baby soybeans in the pod - popular in Japanese restaurants but not the sort of thing you would associate with the Golden Arches.

This willingness to try anything once has led to a fair few failures, too - some of them for unexpected reasons. “We tried a product called the McDouble Cruncher,” he said. “It was like a cheeseburger with barbecue sauce and onions. People liked it so much that when we tested it in restaurants they stopped buying quarter-pounders [a core menu item]. That’s not a good thing. The numbers have to fit; we’re a business.”

Coudreaut’s test kitchen is where the cooks meet the money men - his glass-fronted cooking area on an upper floor of the company’s headquarters on the outskirts of Chicago looks out on to a corridor signposted Big Mac Boulevard and, beyond that, to several rows of wood-panelled office cubicles.

Not that Coudreaut worries too much about the accountants, describing his kitchen as “a sanctuary”. He refuses to discard any new proposal initially on cost grounds, despite McDonald’s reputation for prescription and uniformity.

“It’s nice to be able to try anything, work with anything. No idea in this kitchen is a bad idea,” he said, adding that worrying about cost is only necessary once the company starts to get serious about adding one of his creations to the menu.

He and his team assess about 1,800 concepts a year, and only a handful make it into the restaurants. Ideas can come from the team in the test kitchen, from franchisees or suppliers, and typically take 12 to 18 months to move from drawing board to burger bar.

John Owens, analyst at Morningstar, an equity research firm, said that one of McDonald’s strongest suits in recent years had been its ability to create new items that consumers wanted to eat. “They have been giving their customers more reasons to visit the restaurants more often.”

He said that, as well as new products, the company had been boosted by extending its opening hours and improving its breakfast and coffee offerings. The financial results have been encouraging. Its third-quarter figures published last month showed that same-store sales worldwide had increased by 7.1%. In Europe they were up by 8.2%.

Some products do not work well in overseas markets. The McGriddle, a new breakfast item, has sold well in America but drew little interest on this side of the Atlantic.

Denis Hennequin, the Frenchman who runs McDonald’s in Europe, said: “Because the Big Mac was universally successful, we think every product that McDonald’s introduces should be universal. That’s a mistake.” He argues that the company should aim to be more creative. “You cannot be a leader if you don’t innovate. McDonald’s has been very good for the past 50 years at duplicating the same [thing]. Now it’s time to take a step ahead again.”

The company’s biggest project right now is moving its range of drinks upmarket, with premium coffee to be introduced at all 14,000 of its American restaurants by next summer, and smoothies to follow later.

Some observers have questioned the wisdom of such a move at a time when the world is moving into recession and when there are rumours that franchisees are unhappy about financing the changes. The company denies any problems, insisting the implementation is on schedule and that it is well placed to weather the recession.

In Europe, Hennequin said there was no sign of a slow-down, but he thought the group would have to raise its game to maintain its share in a tougher market.

“Consumers’ purchasing power may be shrinking so you have to give them more,” he said. “It’s the only way to keep them coming.”

That, and a few more recipes from Coudreaut’s kitchen.

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