I love IMBC. It's by far my favorite type of frosting but I keep reading conflicting opinions on how long it can sit out at room temperature. Some say a few hours, some say a day and some sites have mentioned that it can stay fresh on the counter for up to two days. So confusing!
When we were travelling in California last fall, I stopped in at a very cute cupcake shop and had to try one of their cupcakes. It was definitely iced with a meringue buttercream (I asked what kind they used) but it wasn't cold - just right for eating immediately. If a cake shop can display their cupcakes all day at room temperature, I'm guessing that the meringue buttercreams are stable?
Yes, they're stable. The cake inside will go bad before the icing does.
pterrell: How long at room temp would you say they are stable? 1 day? 2? A few hours? I've never worked with IMBC or the like, but would love to try...
Like I said, the cake itself will spoil first before the icing does.
Now, no cake that I've made has ever sat around longer than 3 or 4 days because it gets eaten too fast.
However, we keep a stick of butter in a covered dish out on the counter. It's just hubby and me, so we don't use it up very fast, might take us 10 days to go through a stick. And that's just plain butter, it doesn't have the sugar in it.
As for the eggs, there is some debate over whether the sugar syrup cooks the whites or not. Knowing how quickly egg whites cook and how hot the sugar syrup is when it goes into the eggs and how long the meringue stays extremely hot after the addition of the syrup, I honestly don't see how any bacteria that *might* have been in there could possibly survive. If you're really that wary, you can always use pasturized egg whites or meringue powder.
All that being said, I would say that the icing would probably be fine after 10 days. However, I can't imagine anything sitting around that long. Not if it's tastey, anyway! It's definnitely fine for the day or two it might take to decorate an elaborate cake and then for the day of the party and even a day or two of left-over bits. So, that's about 5 days right there.
Thank you! That really helps!!
(And my in-laws also keep the butter out...always grossed me out, until I got on here and realized it's FINE!
Remember: people didn't always have access to refrigeration. We refrigerate a lot of things that don't technically have to be refrigerated. A lot of what we do put in there, it is to extend the life, not because it's going to spoil immediately.
Also, making butter and cheese were 2 ways people used to preserve milk.
How does fondant hold up on these for two days, does it start to sag? I would think it would be fine, just curious!! I think I have asked this many times, but never reallyl got a definite answer. I have been making the French Vanilla Buttercream from Toba's book lately for my cuppies and it is so freaking delicious!!! I am making a couple of cakes this week, and one requires the PS buttercream and honestly I can't stand the way it tastes anymore, I think I am a convert!!!
As long as the fondant is applied correctly, it shouldn't sag.
If you add a cup of icing sugar when the IMBC is done, it will prolong its shelf life. Last but not least, always use pasteurized egg whites to be for a 100% bacteria free.
Thanks for the replies! I'm so glad to hear that it's stable at room temperature!!