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Why Are My Brownies Bubbling? (3 Common Causes)

Why Are My Brownies Bubbling? (3 Common Causes)

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Brownies are relatively easy to make, but at the same time, if you don’t follow the instructions to the tee or if you choose a recipe that isn’t great, then mistakes can be made. It can be helpful to know some common mistakes created and ways to prevent them so that you can make the perfect batch.

Air bubbles can form in your brownies if you are overmixing, beating your wet ingredients, or adding a chemical leavening agent. You can release the air bubbles by tapping the tray on the kitchen counter, using the correct amount of fat, and using good-quality ingredients in your brownie mix.

A common mistake made is incorporating too many air bubbles into your brownie mixture; this can affect the texture and look of your brownies which is not always desirable. Thankfully there are a few ways this can happen and ways to avoid it.

Why Do My Brownies Have Bubbles?

Having air bubbles in your brownie batter can lead to a few things; your batter may be too light and fluffy instead of the typical dense fudge-like texture. Air bubbles can also lead to cracks forming on the top layer of your brownies, which can diminish the authentic look of your brownies.

Cracks form on the top layer of the brownies because when the batter is heated, the air bubbles expand. When you take the brownie batter out of the oven, the air bubbles collapse because the cold air shocks them, resulting in cracks on the surface. Thankfully there are a few reasons why air bubbles form, and there are specific tips we can use to stop this.

1 – Too Much Air Incorporated

The main reason for the formation of air bubbles is caused by overmixing the batter; this increases the amount of air added to the batter, making it light and airy. This type of textured batter is not desired for brownies which should have a dense batter creating that fudgy, chewy texture.

It is crucial to avoid overmixing; most brownie recipes call for using a spoon to mix the dry and wet ingredients together. Avoid using a whisk or mixer, as this will incorporate air bubbles. Another way air bubbles can be added while mixing is when the recipe asks for the eggs and butter to be beaten before adding to the dry ingredients.

The air bubbles from doing this are then added to the flour, stabilizing them. If there are too many air bubbles to the amount of flour, the batter can collapse or cave in after being baked, as the cool air will cause the air bubbles to deflate.

2 – Chemical Leavener Added

Chemical leavening products such as baking powder or baking soda are not a typical ingredient added into brownie recipes, although some may ask for it to be added. These chemical leaveners can create air bubbles to form in the batter.

To avoid too many unwanted air bubbles, make sure you add the exact amount of baking soda or baking powder it indicates. It is also better to ass it to the dry ingredients, sift it into the ingredients and whisk the dry ingredients to try to mix it in as much as possible before the wet ingredients are added.

3 – Too Much Fat or Poor Quality Ingredients Added

The kind of bubbles formed here are slightly different, but this happens if too much fat like butter or oil is added to the batter or when poor quality or old ingredients are used. When there is too much fat, the batter starts to bubble while baking in the oven, and a layer of unwanted fat forms on the top.

The exact amount of fat required in the recipe must be added to the mixture. Bubbling also happens when old or poor-quality ingredients, specifically chocolate or butter, are added.

This will cause too much fat to be added, resulting in the batter bubbling and a layer of oil forming on the top. Choose new and good quality chocolate such as Callebaut, Valrhona, and Ghirardelli.

Tap the Bubbles Out

Tapping your batter is a great way to release the bubbles. Once you have placed your batter into its baking tray, tap it or lightly drop it onto the kitchen counter to get the air bubbles out before baking.

To make sure all the air bubbles are out, you can take the brownies out of the oven midway through the baking process and tap the tray on the counter a few times.

Is It Air Bubbles or Just a Crispy Crust?

Some recipes are explicitly designed to help form a beautiful crispy meringue-like crust on the top of your brownies; this must not be mistaken for unwanted air bubbles.

You can tell if the recipe is intentionally causing this to happen when it indicates you to beat the eggs, sugar, and butter together before mixing them into the dry ingredients.

This can be a lovely addition to your brownies, but some people don’t enjoy it or only want a little crispy crust on the surface of their brownies. To stop this from happening, don’t beat the butter, sugar, and eggs but instead mix them lightly and don’t overmix the wet and dry ingredients together.

If you want a light crispy layer, then beat the butter, sugar, and eggs for half the time they indicate on the recipe instructions.

Final Thoughts

Air bubbles in your brownie are not wanted as they can make your brownies too light and fluffy, similar to a cake, instead of dense and fudge-like. It is helpful to know what can cause your brownie mix to have too many air bubbles and what happens to the brownies if this happens.

There are different ways to avoid air bubbles from forming in the mixture and ways to get the air bubbles that have developed out of your mixture before they are fully cooked. These are valuable tips to know as a bubbly brownie mix damages your brownies’ texture and authentic look.