Another time this question was ask, the answer was that massa seems to have more emphasis on the first syllable MAssa. Where maçã seems to have more emphasis on the last syllable maÇÃ. Try listening to mutiple translation (bing, google, etc) sites to see if you hear the difference. ~frankiebluej
I'd love a more authoritative answer on this, but it looks like whether the translation is "cuts up," "cuts into," "slices," "is slicing," etc. is basically going to depend on context/translator choice (i.e. they should probably all be accepted):
The verb "fatiar" also exists for the "slices up" meanings.