Royal icing carries a very slight risk of salmonella infection from the raw egg whites used to make it. If you want to eliminate that risk completely, use pasteurized whites, which are available either dried or fresh. Look for dried egg white powder or meringue powder (dried egg white powder plus sugar and stabilizers) in the baking section of the market. You’ll need to reconstitute the powder before making the icing, as in Abby Dodge’s recipe for Royal Icing.
Fresh pasteurized egg whites are kept in the dairy case near the other eggs and egg products. Depending on your store, you may fi nd cartons of whole in-shell pasteurized eggs (look closely at all the cartons because they’re packaged just like regular eggs and are sometimes hard to notice), or you may fi nd containers of liquid egg whites. Use fresh pasteurized egg whites just as you would use regular egg whites.