with 95% of fruit out there if you want to add it to a beer, then carry on as normal for the beer and then add/rack onto it after primary fermentation has slowed/stopped. Let fermentation finish on the new sugar you have just added(in fruit form) and then bottle.
Not all fruits are created equal, some will give you loads of flavor in relatively small amounts(.5 pounds per gallon or so is what I'm calling low) and some will require a lot of fruit to give you flavor.
Some fruits will also fade in the bottle fast than others.
Despite the strong acidity pineapple provides(in good and bad ways) I have found in the camp of needs quite a bit to add flavor, and fades relatively quickly.
I recently put part of a barrel pull of lambic on pineapple(3 pounds for 2.5 gallons) The pineapple flavor is there, but mostly in the finish. Way less pungent than any other fruit I have used.
I used frozen processed pineapple from the grocery store with no additional treatment. I personally like the simplicty and predictability of store bought frozen fruits. Buying fresh fruit, especially out of season, is a crap shoot.
If you wanted to use fresh pineapple I would just chunk it up and freeze it prior to adding it to the secondary to break down cell walls.
As for all this cooking and chiles and whatever...Any cooking or pasteurization will only result in detriment to the flavor of almost all fruits, this would likely hold especially true for a delicate fruit like pineapple.
I have witnessed no negative effect from the enzyme referenced...it is however quite useful for Tacos al Pastor.