I have been searching the forum for an hour on refrigeration topics and I am frustrated. I have steered clear of fruit filling because I am unsure of what needs to be refrigerated for food safety purposes. But, I am getting a lot of requests lately for fillings that are not buttercream. So, specifically, if I use a filling that is a mixture of fruit preserves, condensed milk, and powdered sugar, should this be refrigerated is the cake is made the day before it will be eaten? What makes a filling perishable?

Pretty sure that will be okay for a day. I often use the fruit pie fillings and fold in some buttercream. There is enough sugar in those to be kept out of the fridge for a day or so.

I agree that it should be fine. I never refrigerate any of my cakes.

I have nothing to help you with your question. I just thought your topic subject was so cute. When I read it all I could think of was the agitation of a washing machine. I had this image of your refrigerater agitating your cake. It could be because my washing machine is running and I can hear it.