if there was an infection, you would know. the cum would be gross not only by scent.
sometimes what you eat has an effect on the smell. http://www.collegesexadvice.com/strange-taste.shtml

smoking, drinking coffe and alcohol, eating a lot of meat and spicy foods can cause it to taste and smell bad. any toxin has an effect on it.

or homegirl needs to shave and shower.