I'm terrible at making fruit beers so I have gone to gourmet extracts to get around it. If you want to use real fruit, I would make the cream ale, ferment it and then add the berries to secondary. I would freeze the berries, thaw them and then blend them (or crush them) and add them to the secondary. You could put the berries in a bag with some vodka to attempt to sterilize them or heat them on the stove to 170° or so, then cool and add. You want to add them to secondary so you can preserve their flavor which will get zapped by the heat of the kettle and then further scrubbed out by the activity in primary. But adding then to secondary is going to kick up another fermentation because of the sugars in the fruit. This is not a bad thing but in my experience this has dried out the beer terribly so you might consider mashing the cream ale high (155+) so that there is some residual sweetness left behind. It's a tough balancing act and in 15 years of brewing I have tried everything. Good extracts is how I go now. Good luck.
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