I'm sure that this may have been answered on the forum here somewhere, but I can't find it! ... If I mix pureed and strained strawberries into my buttercream (butter, powd. sug. and extract kind)- must it be refrigerated? I will be covering the cake in fondant and would rather not refrigerate it. Should I use a jello flavoring instead if the answer to refrigeration is yes? Thanks for your help!