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What is a crumb coat?

Are you a baking enthusiast who's always wondered how to achieve that perfectly polished and professional finish on your cakes? Or maybe you've heard of something called a "crumb coat" but you're not quite sure what it is or why it's important. Well, you've come to the right place!

In this blog, we're going to cover the following questions you may have: what is a cake crumb coat, how do you crumb coat a cake, and what are the benefits to crumb coating your cakes? So let's get started!

What is a crumb coat and what does it do?

A crumb coat is a thin layer of buttercream or ganache that is applied to a cake before the final layer of buttercream is added. The purpose of the crumb coat is to seal in any loose crumbs or cake debris that may be present on the surface of the cake, creating a smooth and even surface for the final layer of buttercream.

To create a crumb coat, a small amount of buttercream or ganache is spread over the cake using an angled spatula, making sure to cover the entire surface. This initial layer should be thin and even, with just enough coverage to seal in any crumbs. The cake is then chilled in the refrigerator or freezer for a short period of time to allow the crumb coat to set.

Once the crumb coat is set, the final layer of buttercream can be applied. Because the cake has been sealed with the crumb coat, the final layer of buttercream will go on smoothly and cleanly without any loose crumbs getting in the way.

How to apply a crumb coat with buttercream or ganache

To crumb coat a cake, you will need either ganache or buttercream (my go-to is Swiss meringue buttercream) that is at room temperature and slightly thinner than your usual consistency. An angled spatula will also be necessary to apply the crumb coat to the cake.

If you're using ganache to crumb coat your cake, the process is similar, but you may need to adjust the consistency of your ganache to make it easier to spread. To do this, you can heat the ganache slightly in the microwave or over a double boiler until it is slightly thinner than usual. Make sure if you're using a microwave that you are heating in short 10 second bursts or your ganache may split.

Here are the steps to crumb coat a cake with buttercream or ganache:

  1. Bake your chosen sponges and allow them to cool completely before applying the buttercream or ganache. Any sponge will work for this technique, but you can check out some recommended recipes for light and fluffy sponge cakes here.

  2. Level your sponges and stack them with your chosen buttercream or ganache and your additional fillings between each layer. You can learn how to stack a buttercream cake as part of the Buttercream Basics course.

  3. Prepare your buttercream or ganache: Make your chosen crumb coat according to your recipe until it is smooth and slightly thinner than usual.

  4. Apply a thin layer of your crumb coat: Using an angled spatula, apply a thin layer of ganache or buttercream to the top of your cake, spreading it outwards towards the edges. Make sure you cover the entire surface of the cake with a thin and even layer.

  5. Smooth out the crumb coat: Use a stainless steel cake scraper or an angled spatula to smooth the surface as best as you can, making sure it's evenly distributed across the cake. Don't worry too much about it being perfect at this stage - the goal is to create a smooth surface to hold in the crumbs.

  6. Chill the cake: Once your cake is stacked and evenly coated in your choice of crumb coat, place the cake in the refrigerator for at least 30 minutes, or in the freezer for a maximum of 20 minutes until the buttercream or ganache sets firm.

  7. Decorate your cake: With the crumb coat in place, you can now decorate your cake as desired, whether that's with additional ganache, buttercream piping, or decorations. You can learn how to create a smooth, sharp edge buttercream cake with step by step video tutorials on our online Buttercream Basics course.

Overall, whether you're using buttercream or ganache to crumb coat your cake, the key is to start with a thin and even layer to seal in any crumbs and create a smooth surface for the final layer of decoration. And that's it - with a little bit of patience and attention to detail, you can create a perfectly crumb-free cake with a beautiful finish.

What are the benefits to using a crumb coat on your cake

There are several benefits to using a crumb coat on a cake when decorating:

  1. Sealing in crumbs: One of the primary benefits of a crumb coat is that it seals in any loose crumbs or debris on the surface of the cake, preventing them from getting into the final layer of buttercream or decoration. This helps create a clean and polished finish to the cake.

  2. Even surface: Applying a crumb coat creates a smooth and even surface for the final layer of frosting or decoration to adhere to. Without a crumb coat, it can be difficult to achieve a clean and even finish on the cake. If your cake layers are a little wonky or some of your sponge has crumbled away, the crumb coat allows you to create a stable base for applying a second coat of buttercream.

  3. Easier to decorate: With the crumbs sealed in and the surface smoothed out, it is easier to decorate the cake without worrying about crumbs getting in the way or creating an uneven finish.

  4. Professional-looking finish: Using a crumb coat helps create a professional-looking finish to the cake, making it look like it was done by a skilled decorator.

  5. Longer shelf life: By sealing in any loose crumbs and debris, a crumb coat helps the cake to maintain its integrity and shape for a longer period of time, making it possible to make the cake in advance of an event or celebration. You can also store a crumb coated cake in the fridge whilst you prefer your final layer of buttercream without the sponges going stale.

Overall, a crumb coat is an essential step in the cake decorating process that helps create a polished and professional-looking finished product.

Learn how to decorate cakes like a pro!

Learning the key techniques to stacking, smoothing and decorating a buttercream cake can be tricky without the correct guidance. Our online Buttercream Basics course contains three in-depth modules which take you through every step of decorating with Swiss meringue buttercream.

If you wanted to go a step further and learn how to paint with Swiss meringue buttercream, how to use edible gold foil and decorate a cake with fresh flowers, we have the perfect course for you! The Buttercream & Design Masterclass features 10 modules to take you from an amateur baker to a skilled professional cake decorator!

You can find more information on all the available online cake decorating courses here.



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