The drink blends 60% fruit juice from grapes, apples and raspberries with natural sparkling water. It contains no added sugar, other than natural sugar from the fruit.
A 250ml serving contains 25 grams of sugar, which a McDonald’s spokeswoman claimed equated to approximately six teaspoons of sugar while a "similar-sized smoothie or a fresh juice would contain around seven teaspoons of sugar".
Fruitizz will be served from the central drinks tower containing the other fizzy drinks, which includes the Coca-Cola brands. Research has revealed children thought drinks poured from the towers were more exciting and desirable.
Jill McDonald, chief executive and president of McDonald’s UK, said: "For the past three years, we have been working hard behind the scenes to create a fizzy drink that is unlike anything else currently available in high street restaurants.
"We tried and tested 80 formulations in order to create the right product that delivers nutritional benefit as well as a new, exciting taste."
McDonald’s restaurants will serve the drink nationwide from next Wednesday (16 May). An "extensive" ad campaign by Leo Burnett, including TV, print and digital media starts on the same date.
McDonald's pointed out that Fruitizz, which it piloted last year in Wales, was the latest new product in a series of improvements that have been made to its menu over the last decade.
Fruitizz takes a place on the Happy Meal menu alongside carrot sticks, fruit bags, mineral water and organic semi-skimmed milk.
In January it emerged McDonalds is piloting a new style of re-designed "family friendly" restaurant, to better cater for children and for users of tablets and smartphones.
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