Carmel,

I wouldn't worry about this behaviour as it is quite common. One of my cats always uses this motion to try and cover up his food. Cats cover up things to prevent the smell escaping (as with their faeces). This motion you have discribed is just your cat saying he doesn't approve of the smell - you'll probably find he still actually eats the food but just doesn't seem to like the smell. In the wild felines will always cover up their faeces unless they are the "top cat" of the area - in which case they wan't everyone to know they are the boss and this is "their" smell.

You and your cat have nothing to worry about - as long as your kitten is healthy and is eating then this behaviour should just be seen as endearing

Good luck...