Swiss Meringue Buttercream: 4 FAQS ANSWERED!


What is this magical frosting, you ask? It is my FAVORITE buttercream I use for frosting my cakes. It is super smooth, silky, and doesn’t taste too sweet - which if you know me - I hate overly sweet things!

I wanted to share 4 frequently asked questions about Swiss Meringue Buttercream (SMBC) today! Hopefully these tips will help you out next time you run into any issues.

Question #1: Why is my buttercream grainy?

Grainy buttercream usually happens during the process of heating the egg whites and the sugar. If you don’t heat it long enough, the sugar granules won’t dissolve, leaving a grainy texture even after you beat in your butter.

MY TIP: You can check if your egg white and sugar mixture is done by rubbing a little bit of the mixture between your fingers If you can’t feel any sugar granules and it is smooth, you are good to go!

Question 2: Why is my buttercream curdled?  

This is probably the most commonly asked question about Swiss Meringue Buttercream! This happens after you add in your butter to your stiffened meringue. This is totally normal though and you have nothing to worry about.  I usually notice my buttercream curdling in the very beginning, but after letting it beat for a while, it turns out silky and smooth.

MY TIPS: Don’t let your egg white and sugar mixture heat at such a high speed that you cook part of the egg whites!  Also, don’t overbeat your meringue - If you overwhip your meringue, it can cause it to break, and this can add more to the curdling issue. Second, don’t let your butter get too soft or be on the verge of melting. Also, use your paddle attachment when you’re whipping in your butter.  

Question 3: Why is my buttercream runny?  

Runny buttercream can either happen when you’re adding in butter while the meringue is still warm, or if you’re adding melted butter or just super soft butter, OR it could be a combination of both of these.

MY TIPS: One thing you can do is place your entire bowl of buttercream into the fridge to stiffen it up. Once it is hardened, you can place it back into your mixer and whip it with your paddle attachment.  You can easily avoid all of this though if you just make sure you beat your meringue to stiff peaks and use butter that is soft but not melted.

Question 4: Why is my buttercream airy?  

Airy buttercream can happen in a couple different ways:  One of them is if if you’re whipping your buttercream at a very high speed for a long time.  Another reason is if you’re using your whisk attachment when you’re beating in your butter because that can incorporate more air.  Another way you can get airy buttercream is if you leave your Swiss Meringue Buttercream out at room temperature for a couple days.

MY TIPS: Make sure to use your paddle attachment when whipping in your butter, mix at a lower speed for a longer time, and at the very end, use a wooden spoon or spatula to mix by hand and knock out any remaining air bubbles.

I hope all of these tips help! If you have another question that I didn’t get to answer here, let me know in the comments.

Want my foolproof Swiss Meringue Buttercream recipe that doesn’t deal with any of these issues?!

Check out my YouTube video below all about this topic as well!