Hi,
I am a cake novice and would like to use a Swiss or Italian Merengue Buttercream to cover a cake. The cake will have to be left out for a bit and I am nervous that the buttercream will get to soft and melt if it gets to warm at the party. Has anyone ever mixed shortening and butter into a merengue based buttercream? I am thinking that might help keep the buttercream together since the shortening melts at a higher temp than butter. Am I worried for nothing? Thanks in advance for your help

The meringue buttercreams are fairly stable, so I wouldn't bother adding shortening. What temperature is it going to be sitting out at? You should refrigerate it before you deliver it, and by the time it's cut it will be fine unless it's out in the full sun at 95 degrees.

I sometimes use 10 to 20% shortening in my SMBC in the summer with no problem. It rarely gets above 25C here.

Interesting idea, I have a bunch of cupcakes to do and was wondering if it made it a bit more stable so my swirls stay nice and peaked? (Does that make sense?) LOL!

Shortening and IMBC/SMBC:

http://forum.cakecentral.com/cake-decorating-ftopict-33536-.html

http://forum.cakecentral.com/cake-decorating-ftopict-409473-.html

Toba Garrett's SMBC has a warm weather variation that adds a little hi-ratio shortening for stability:

http://www.epicurious.com/recipes/food/views/109239

HTH

Thank you all for your help!