I was making RI and discovered that I did not have enough Meringue powder for the recipe, so I had to make it with real egg white. I need to make some decorations ahead of time to get them hardened but is that safe with egg white or only Meringue powder?
Anyone? I am guessing with all the sugar, its probably ok- I would eat it, but maybe it should be refrigerated while it hardens? Or will that make it soft again?
If you look up Royal Icing and Food Safety you find info like this
I'm not sure of the definitive answer; lots of RI recipes call for "egg whites" rather than "meringue powder" so I would assume that the icing has been made with raw egg whites for eons. Then again so are certain sauces, Caesar dressing, etc. and none can be guaranteed to be safe. You just sort of take your chances.
Even the American Egg Board doesn't give a specific answer, except to say that egg whites should be cooked http://www.incredibleegg.org/egg-facts/egg-safety/safe-food-handling-tips
One thing to keep in mind is that there is something like a 1 in 20K occurrence of salmonella in eggs so the odds are low of it being contaminated.
I've never seen refrigeration recommended for royal icing, even in recipes which call for egg whites.
It is quite safe to make decorations ahead of time using RI with egg whites. I was brought up with RI and now use it myself, I've never been poisoned yet. Also it won't harden if you refrigerate it. It needs to be left out in a safe place. HTH
I have frozen mine for about a week, thawed it out and used it. Works just fine.