I used to be against fruit in my beer. Then I learned how to brew berliners.
I did this with raspberries:
Got them frozen, thawed, froze again, thawed again. Use funnel to get in secondary carboy, rack beer onto them. This is after primary is finished, but a secondary ferm kicked off.
Raspberries were mush due to the abuse, this is what I wanted. Read that it will break down cell walls and impart more flavor. Figured comerrcial freezing would specifically want to avoid breakin cells down so I thawed them and refroze them to be sure.
Didn't use a bag or anything, just threw them in. They floated and turned white as the color was drained, pretty damn cool. Dumped right out like slurry, overnight soak in PBW eliminated any residual raspberry matter. Didn't filter, auto-siphon transfer to bottling bucket kept most out. Maybe a few piece slipped in a bottle or two, part of the charm if you ask me.
Used 3.2lbs in 5 gallons. Very raspberry forward aroma, slightly less on taste but it was rasberry and lacto up front in a wonderful combination.
Doing another one tomorrow, time to rack it on raspberries, going with 4.5lbs this time. Looking for that new glarus fruit bomb profile.