Cream Cheese Frosting Disaster

My daughter is living in London and sent me a question this morning about several failed attempts to make cream cheese frosting for a birthday cake. She used "icing sugar" as a substitute for American powdered sugar, along with room temperature cream cheese and butter. The problem was the more icing sugar she added the soupier and more liquid the frosting became. It seems a bit odd. Does anyone out there know why this happened? She tried the recipe again, the second time adding half the amount of sugar. The frosting was thick, but not sweet enough and a bit cheesy-tasting. The recipe works fine in the US....?



Incognito March 31, 2012
Many thanks to those who answered! We will try Boulangere's addition of heavy cream and see if that does the trick. Otherwise, we will be back to the Hotline!
ChefOno March 29, 2012
I didn't mean to contradict boulangere (if I did). Our responses crossed in the either.
ChefOno March 29, 2012
My guess is the mixture thinned out due to the heat generated by the mixing action. A 10-degree rise is not unusual. I think the statement above is correct but I aim for a starting temperature of 60F (15C).

boulangere March 29, 2012
The more sugar is added, the more water is pulled out of the cream cheese because sugar has a great affinity for water. I always work with room temperature cream cheese for everything I use it for. That said, room temp and "warm," as hla suggests, are two very different things. She should start with only the amount the recipe calls for. If it seems too thin, she can add heavy cream a tablespoon at a time to thicken it up. I know, it sounds counterintuitive, but the cold cream reduces the temp of the cream cheese and causes it to firm up some.
hardlikearmour March 29, 2012
As far as I know icing sugar is the same as powdered sugar. I wonder if the cream cheese was too warm - Joy of Cooking recommends it be cold . The butter should be softened but still cool - 68 to 70 degrees. Perhaps she over-mixed the frosting in which case it tends to get grainy and soupy.
HalfPint March 29, 2012
Did she use corn-free (CF) icing sugar? That's the only difference that I can think of. She might need the use the icing sugar with cornstarch which is in the powdered sugar in the US.
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