Can someone please explain why some buttercreams crust and others dont. How should I know the difference when looking at buttercream recipes. I am looking for a buttercream that crusts but is made with real butter and not Crisco.
Thanks,
Jade8

Crusting is based on the sugar to fat ration in Buttercream. The more fat (butter or shortening) the slowery it crust, and depending on the ratio may not crust at all. The more powder sugar in the recipe the more/faster it crusts.

For me I use 1 cup of fat to a 1lb of sugar as a good starting ratio. Yes there are recipes out there, IndyDebi's for one, that uses less fat then that but crusts great. So that ratio is just to give you a beginning point. If you have 2 cups of fat to lb of powder sugar it will be much slower to crust over.

There are some recipes, like cooked buttercreams that won't crust. These are your meringues which are made with eggs, granular sugar and butter.

Crusting is caused by evaporation in the top most layer of the frosting. So your recipe must have some liquid in it for that to happen. (That's why the meringue b/c's will never crust, and why an American b/c with a high percentage of fat to powdered sugar will be slow to crust or might not crust at all.)

HTH

I don't know of any buttercreams that crust which don't contain some sort of shortening. Maybe someone on here does.

Are you opposed to all shortening or just Crisco?

I'm very interested in this as well, and am looking for a good crusting BC that does not use Crisco or shortening. Only butter....

Maybe its the thought of eating shortening all together vs butter that is at least real.

You can use butter in a crusting recipe. It may take less liquid and may take a little longer to crust but I don't know why it wouldn't crust?

Of course my issues with working with all butter buttercream come from it being softer to work with and my hands are warm so it doesn't hold up to piping as well as the all crisco recipe does.

I had to make a crusting BC the other day....well, actually, I was asked to make "that old style you used to make, before this smooth stuff"...ok. Oh, but with butter. Ok.

I took a couple of sticks of butter, threw them into mixer, started dumping PS in, added vanilla and milk, and bam....there ya go mom.

It was yummy. But I'm still not giving up my SMBC.