So - adding pineapple to the food. Is this the crushed pineapple?
Depends how you can get them to eat it, I used canned pineapple about a tablespoon full on each meal (for both dogs). The juice works too so if not a fan of eating the chunks can soak their regular food in the juice. We were lucky both Indi and Callie are fruit and veggie eaters they love the stuff can't eat a banana without them hearing you and coming to get their share so we didn't have any issues.

Marlowe went through poop-eating phase but, mercifully, he has a cast iron stomach.