Posts Tagged ‘air bubbles under fondant’

Air Bubbles Under Fondant aka Cake Farts

Sunday, May 23rd, 2010

Recently in London the weather has been warming up (shock horror!) which has been causing havoc with some of my cake making. Those of you who work regularly with rolled fondant (called sugarpaste here in the UK) and buttercream know that heat can be your worst enemy when it comes to cake decorating.

Our flat, in typical London fashion, has heating but no air conditioning. The kitchen is near the back of the apartment, as far away from the windows as you can get. So on a warm day, it’s like an oven in the kitchen, somewhat ironically. One of the tricks I use when it’s warm and my buttercream is melting is to put my cake in the freezer once it has the crumb coat on. Just for a little while to let the buttercream get nice and stiff so it doesn’t move around when I put the rolled fondant on it. This usually works really well and helps me achieve a nice smooth covering on the cake.

However, using this method in the heat has meant that recently I have been getting small air bubbles on some of my cakes. This is unusual for me, but not a big deal as I can usually smooth them out without too much difficulty. But then of course, there was the one time this week when it was an absolute disaster!

I made a cake and left it in the freezer for far too long – about 40 minutes! When I covered it with fondant, everything seemed fine. I got a nice smooth covering on the cake and left it to dry. I came back an hour later and found a small air bubble under the rolled fondant. Not a big deal, I smoothed it out and transferred the cake to the fondant covered cake board, cementing it securely to the board. I left it for a half hour then went to put some ribbon around the cake while the icing was still slightly wet. And I nearly fainted when I saw it!

There was not one, but two HUGE air bubbles under my fondant!!! Mice could have crawled under there and set up camp they were so big! (Please note: I do NOT have any mice in my flat). It was a deformed, bubbly  mess. The back of the cake reminded me of a witch’s hooked, crooked nose, and the top of the cake looked like the elephant man. It looked like something that belonged on the Cake Wrecks blog!

I have covered quite a few cakes with fondant in my time and NEVER had this happen before. Which prompts me now to explain how it did happen this time. When you cover a cold cake with fondant, small pockets of air are released as the cake warms up and returns to room temperature. This causes a bubble of air to be trapped under the fondant. It’s what we call in the biz a “cake fart” as the cake is releasing gases! This had been happening a little with my cakes recently due to them being put in the freezer then taken out into a very warm room. A small air bubble is no biggy, but if you have a very cold cake in a very warm room, your air bubbles will be particularly bad and ginormous. Which is what happened in this situation as I’d left the cake in the freezer too long!

So how did I fix the problem? Removing the fondant and re-covering is really a very last resort, especially when you’ve already fixed the cake onto the covered board. So what I do is sterilise a very thin pin or needle, then poke a small hole into the air bubble at an angle. I then get my cake smoothers and push the air out of the offending bubble, then smooth over the area with the paddles. If the hole is very noticeable, you can cover it with decoration such as a flower or ribbon, but if it’s somewhere on the cake that isn’t going to get covered with decoration, you can also mix a small amount of rolled fondant with water and fill the hole in, then smooth with your smoothing paddles. And voila, it’s like your air bubble never existed!

I don’t have any pictures of the cake fart disaster to show you as I was in such a panic at the time that I didn’t even think to grab my camera and document the moment. But here are some pics of another cake which had an air bubble which I fixed with the pin method:

Before – you can clearly see an air bubble has formed around the wooden post

After – air bubble, what air bubble?

 

UPDATED 2016: This is by far my most popular post! I’ve noticed that some of you are confused between cake farts and normal air bubbles. The cake fart is different to a normal air bubble, it’s caused by a dramatic enough difference in temperature between the fridge/freezer and the room temperature and it usually forms some time after you’ve covered your cake if you covered a cold cake. So you’ll cover your cake perfectly and come back later to find HUGE air bubbles that weren’t there before.

Many cake makers cover cakes straight from the fridge or freezer with no problems because the room they take the cake out into from the fridge/freezer isn’t too hot. I usually can’t because it’s so hot and humid in Australia and I don’t have a temperature controlled room (no air con, it’s brutal!). I use ganache instead of buttercream now and always cover a room temp cake so cake farts are a thing of the past.

Normal air bubbles form straight away as you cover your cake. I get these either because I missed a spot when wetting my ganache before covering the cake or the fondant didn’t quite stick down to the surface in a spot when covering the cake, these air bubbles are usually quite small (cake farts can be humungazoid). I don’t know any cake decorator that doesn’t get these kind of air bubbles, but they’re easily taken care of with the pin trick as soon as you cover your cake. Air bubbles are all but impossible to get rid of once your fondant has set hard.

Check out the comments for other people’s ideas and solutions.