Are you talking about the occasional plants that actually grow a round seed pod on the plant above the ground?
If that is what you are talking about, I wouldn't use them as they, in that state, are totally poisonous. I did research on this phenomenon and the experts say don't use them, get rid of them. And, if you saw these things on your potato plant and you have pets or children, put on throw away gloves, get them off and dispose of them where pets/children couldn't get to them.
I know there is some older guy on the net who plants them and I listened to his whole UTube presentation. I still would listen to the pros who say don't use them.
Umm, the potato fruits may be poisonous, but you aren’t eating the fruits.
Potato seeds can be cleaned and grown in much the same way as tomato seeds. This is where new potato varieties come from.