Cream cheese frosting
A much wetter system than a butter icing, which is why the standard advice for a runny batch — add more icing sugar — eventually makes it worse.
What makes it set
Solid fat, and An emulsion
A baked product is set by the oven. This one is not — and what sets it instead decides almost everything that can go wrong with it. See the whole family by mechanism.
Also called cream cheese icing (UK), cream cheese buttercream (INTERNATIONAL)
Cream cheese frosting is cream cheese and butter beaten with icing sugar, and it is the standard finish for carrot cake, red velvet and cinnamon rolls. It behaves quite differently from a butter-only icing, and the reason is water.
Butter is roughly four fifths fat. Full-fat cream cheese is roughly a third fat and more than half water. Replacing part of the butter with cream cheese therefore does not simply change the flavour — it changes the system, from something that is nearly all fat into something with a substantial water phase. That water is where the tang comes from, where the softness comes from, and where the trouble comes from.
It is always softer than buttercream, it always needs refrigerating, and it is never going to hold a sharply piped edge at room temperature. Those are properties of the ingredient rather than failures of the method.
What holds it together
A fat network of butter and cream cheese fat, holding a substantial dissolved-sugar water phase contributed by the cheese. The fat carries the structure and the water phase determines how soft that structure can be.
Follows from the composition of the two ingredients as recorded on their own pages, together with BakeHQ's fat plasticity record.
RecordedFollows from evidence recorded elsewhere on BakeHQ
What temperature does to it
More sensitive than buttercream in both directions and with a narrower usable range, because the fat that has to carry the structure is diluted by water that does not. It slumps at a room temperature a buttercream would tolerate, and it stiffens usefully in the fridge — which is the reliable way to firm it, and the only one that does not change what it tastes like.
RecordedFollows from evidence recorded elsewhere on BakeHQ
How it keeps
Refrigerated, and a cake finished with it is refrigerated too. It is the one icing in this family where that is not a preference: it contains fresh soft cheese, and it is not preserved by sugar the way a nearly-dry royal icing is.
Storage practice rather than a food-safety judgement, which BakeHQ does not make.
RecordedEstablished practice, not a measured result
What a good one is like
- Texture
- Soft, smooth and spreadable straight from a short rest out of the fridge
- Structure
- Holds a swirl, not a sharp piped edge — and only while it is cool
- Flavour
- Tangy against the sweetness; if it tastes only sweet, there is too much sugar in it
Where it stops
This is not a warm-room icing and it is not a piping icing, and both limits come from the same place: the fat fraction is too low to carry a rigid structure. It also cannot be made stiffer by adding sugar past a certain point, for the reason set out below. And low-fat or spreadable cream cheese makes it worse rather than lighter — those products carry more water and often added gums, and both push the system further in the direction that was already the problem.
Why the usual advice runs out
Almost every source, asked what to do about a runny cream cheese frosting, says to add more icing sugar. For a while that works, and then it stops working and starts doing harm, and the point at which it turns is not signposted.
Sugar added to a nearly-fat-only icing behaves as a solid filler and stiffens it. Sugar added to a system with free water dissolves in that water. Up to the point where the water is saturated, that thickens things — a syrup is thicker than water. Past it, the extra sugar has nowhere to dissolve, the mixture is already as sweet as anybody wants, and further additions do nothing useful. Meanwhile every spoonful has been beaten in, and beating warms the fat that was holding the whole thing up.
The corrections that do work are all about the fat. Chill it. Use full-fat block cream cheese rather than the spreadable tub, which carries more water. Increase the proportion of butter, which raises the fat fraction rather than the sugar. And drain or press the cream cheese first if it looks wet in the packet.
Related
Things that go wrong
Buttercream is runny, split or grainy
The same two mechanisms apply, and the water the cream cheese brings makes the temperature one bite sooner.
Used on and in
The conventional pairing, and a functional one: the acidity cuts a cake that is both sweet and oily.
The traditional finish, and the one that carries the acid theme the cake's buttermilk and vinegar started.
What it is built from
Brings the tang and, more consequentially, a large quantity of water into a system that would otherwise be nearly all fat.
Raises the fat fraction back up. Increasing it is the correction that works when the frosting is too soft; more sugar is not.
The science behind it
Fat plasticity and crystal structure
Same mechanism as buttercream, with a smaller fat fraction carrying it — which is why the usable temperature range is narrower.
Commonly confused with
Called “frosting” interchangeably in American usage, and the water the cream cheese brings makes them behave differently enough that the same fix does not work on both.
Keep reading
Royal icing
Sets by sugar drying out rather than by solid fat, which is why the same complaint means something different in each.
Buttercream is runny, split or grainy
Work through what you can actually observe, rather than a list of possibilities.
Fillings, icings and creams
The whole family, grouped by what sets each one.