As best I can tell, all fruit and vegetables are invisible unless you are actively holding them. At first, I thought the game had just cut WAY down on the amount of food in-game. However, I've accidentally run across now several occasions where, when I hit tab next to an item nearby, there was also a blank square. Howevering over the square showed a mouseover description of a potato or banana. I could interact with it normally, but it is invisible unless you are holding it, and even then I'm not certain if it shows up outside of inventory view, I just know it showed up in the "held" inventory box.