I'm making an English wedding cake and covered it in marzipan. First I used 10 X powdered sugar, which has corn starch in it, to roll the marzipan in. Will this spoil the cake and marzipan? The recipe said to let it dry out for a few days and with the weather being so hot lately, do I have to worry about spoilage from that? I,m very concerned about these two issues. Can anyone help?

http://www.planetcake.com.au/forums/viewtopic.php?t=1238

Lot of great info on this link.

Basically, the corn flour in the powdered sugar will make the marzipan ferment and go mouldy. I think this is only an issue if you are making it way in advance or saving a tier for a long time. I wouldn't think it would go mouldy in the space of a week.

never use corn starch with fruit cake as it does ferment and go mouldy i think you might get away with a week but any longer then its a deffinate no, also you should wait at least four days for the marzipan to harden up a bit before covering it, most people keep fruitcake for their anniversary so i would double check on that, i am from the uk and that is the tradition over here hth