I am making 5 half sheet cakes and 4 6" cakes for a friends daughters communion. They are all being covered in buttercream but they are being filled with a strawberry filling. She needs the cakes Friday morning for Saturday but i want to do as much as possible beforehand. How far in advance do you think i can make the filling?
I think you can certainly make the filling a few days in advance, but It has to be refridgerated.
I have been making Raspberry Puree Filling by melysa, on this site for years. I substitute frozen strawberries all the time. It will last quite a while, in the refrigerator, but I also freeze it. When it is thawed, I zap it in the microwave 20 seconds at a time and stir in between. Although, it separates just a bit in the thawing process, it comes back together after microwaving. Absolutely yummy!
No problem with it sitting out after filling your cake. I fill my cakes the day before decorating and there are no health issues with fruit and sugar.