sddsddean - There have been a lot of Q's on this subject - there must be dozens in the search engine! You're right that Ross Kemp did do the Fruit'n'Fibre ad, where he was prancing about on a golf course, but the tune was different - although I can't recall exactly what it was. But I think the general opinion is that the phrase questioned here came from the Bran Flakes ad.
Fruit & Fibre had the jingle that listed the ingredients in rhyme - "Apples, hazlenuts, sultanas, raisins, coconut, bananas"... or something like that. I