I think I want to make Peach Ginger melomel. The recipe is in Ken Schramm’s book and it calls for 10-12 lbs of fresh peaches. Would it be ok to use frozen peaches instead? If so, would the amount be the same? Also, the recipe has the fruit put into the primary but if I use frozen would that change things?
I would think you’d be ok to a 1:1 substitution. For that matter, I’d be surprised if Ken doesn’t freeze the fruit briefly before adding it to the mead anyways - after all freezing helps break the fruit down via ice crystallization busting cell walls.
I wouldn’t be surprised either. I’ll bet he does freeze them. 
I is smrt sometimes! 