It maybe the pasta Is complex carbs and takes some breaking down or the qauntity . I find if I over eat at a cp I have a down time afterwards as the body pulls blood from other parts( the big muscles in the legs esp.) to digest it. Saying that it is important to eat and drink on long runs. A steady nibble with the small meal at cps works best for me. I find custard or rice pudding good. But need some savoury food as I get fed up of sweet stuff after a while. You'll eat more if its cold too. Happy experimenting he's :-)