It is bad news for chefs such as Oliver, who has a long-standing association with Sainsbury's, and Ramsay, who has started to offer luxury readymeals, starting at £26 for a dinner for two.
The most popular celebrity food brands were not even linked to chefs, Mintel discovered. Loyd Grossman sauces and Linda McCartney frozen vegetarian meals were the top two brands. Jamie Oliver came in third place.
Claire Hatcher, a senior market analyst at Mintel, said: "While several chefs have become part of this celebrity set, this has done little to boost interest in products. It is unlikely that celebrity endorsement of food and drink products will expand."
Sainsbury's has said it has no plans to end its relationship with Oliver. In his new series, 'Jamie's School Dinners', which launches on Channel 4 this week, he tries to persuade children to eat their greens.
However, two weeks ago Sainsbury's began a review of its £47m advertising account out of Abbott Mead Vickers BBDO. It is part of a wider business appraisal by the supermarket chain's chief executive, Justin King.
The review, which is being coordinated by the Haystack Group, could result in Oliver being axed as brand spokesman. The chef has fronted the supermarket's campaign for the past five years and his contract is due to expire in May.
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