Not sure what exactly you mean by the poop being whiteish but I was told that greenish poop might mean an infection of the digestive system, i.e. bacteria that should not be there (my son had e-coli and it was very green).
Is it possible the whiteish stuff is mucus? That would also indicate infection. Howeve if it every now and then it probably is not it (and you would notice other signs like fever)... One thing I can say for sure is that it's worth taking a sample to the lab.
Regards
My13 months old has khaki coloured/light-brownish, almost whitish colour poop every now and then. She had it yesterday and she was crying a lot while doing it. Everytime, I go to the doc, I forget to mention it. Did anyone else's baby have that? It's not cow's milk as I stopped giving it to her last few days.