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Cakey vs. Gooey Brownies – The Science Behind A Brownie’s Texture
Deceptively simple to make, yet, so many ways to make them: brownies.
There must be thousands of recipes for making brownies. And most of them will probably make a delicious brownie. But, you might be looking for one that’s a little more gooey. Or do you prefer yours slightly more cakey? Sure, you can test countless recipes, until you find your perfect one. But, by using a little bit of science, you can also tweak almost any brownie recipe to make it just the way you like it!
- Gooey vs. Cakey Brownies
- Tweaking ingredients to change the consistency
- Impact of process on consistency
- References
Gooey vs. Cakey Brownies
There are countless ways to tweak brownies, but, one of the most common basic distinctions is that between a gooey or cakey brownie. Should it be moist, slightly sticky, dense and soft? That is, should it be gooey, or fudgy? Or, should it be fluffy, a little dry, and crumble apart more easily, that is: cakey?
It’s a sliding scale, and you can make just about any brownie texture from very gooey, to very cakey. Some might call brownies that fall in the middle chewy, however, we’ll just call them slightly gooey, or slightly cakey. And, since we all have different personal preferences there’s not one ‘perfect’ brownie recipe out there. It’s up to you to make your own ‘perfect’.
In creating that ideal brownie, there are two main levers you can pull and we’ll have a look at both:
- The ingredients: which and in which quantities
- The process: how you make the batter, and, most importantly, bake them
Looking for a brownie with a crispy top specifically? Then read our guide on crispy top brownies.
Tweaking ingredients to change the consistency
To evaluate the impact of ingredients on the consistency of brownies, we will use one basic recipe. There are countless more variations (black bean brownies anyone?), but, the science behind the types of ingredients will be similar for all. Our simple brownie recipe uses the following ingredients:
- Chocolate: milk, dark or extra dark
- Cocoa powder
- Butter: or (plant-based) margarine
- White wheat flour: e.g. all purpose flour
- Sugar: white or brown, not a syrup
- Eggs
- Baking powder
By increasing, or decreasing the quantities of each ingredient, you can tweak the final consistency. Of course, tweaking quantities also impacts flavor, but, for now, we’ll focus on the gooey- vs cakeyness.
Butter & Chocolate (the fats) increase gooeyness
Generally speaking, the best way to increase the gooeyness of your brownie is to increase the fatty ingredients. Fats are a group of molecules that make food taste creamy and rich. As such, they contribute to the gooeyness of a brownie. In our brownies, the main fatty ingredients are chocolate and butter. Butter contains over 80% of fat whereas most chocolates will contain up from 30-35% fat. As such, increasing the amount of chocolate and butter in your recipe will increase the gooeyness of your brownie.
But, there is such a thing as too much gooeyness! At high temperatures most fats melt, at lower temperatures, they set. Molten fats especially can form, or hold onto sturdy structures. Molten fat simply forms a puddle. So, if a brownie contains too much fat it will simply collapse. It’s a matter of balance.
Can you use oil instead butter?
Instead of butter (or margarine), brownie recipes may call for oil. Chemically speaking, oils and the fats in butter are very similar. The main distinction is the point at which they turn solid. Butter fats are semi-solid at room temperature, whereas oils are liquid at room temperature. When a brownie that was made with butter cools down after baking part of the fat will turn solid again. However, the oil will remain liquid. As such, brownies made with oils tend to be a little softer than those made with equal amounts of butter. And, they’re also a bit more prone to oil leaking out. Butter on the other hand contributes more to the overall flavor of a brownie.
Researchers have been doing a lot of work on trying to find fat replacers since they do contain a lot of calories. However, this hasn’t been easy. One unexpected successful replacement for fats seems to be beans! They can help create that creamy, rich structure.
Cocoa powder helps make a more cakey brownie
Chocolate is made of mostly cocoa butter, sugar, cocoa powder, and possibly some milk. Most of the chocolatey flavor comes from just one ingredient: the cocoa powder. Most of the fat on the other hand comes from the cocoa butter. As such, if you want to reduce the amount of fat, but keep the strong chocolate flavor, you’ll need to use unsweetened cocoa powder. Most cocoa powders contain anywhere from 10-20% fat, a lot less than chocolate! It’s why using cocoa powder will make a more cakey brownie.
Cocoa powder also helps to thicken and firm up a brownie because it is so dry. It will hold on to some moisture (though not as much as flour does) and bind the brownie as a whole. That also results in a less fudgy brownie.
Flour increases cakeyness
You can’t make brownies with just fats. You’d end up with a puddle. You need other ingredients to bring it together. One of those is flour. You can make brownies without flour (or other starch), but they’ll be on the gooey side of the spectrum. Flour helps to create that cakey texture. Wheat flour is made up of mostly starch. The starch absorbs water, swells and sets in the oven through a process called gelatinization. This process creates the structure of bread, thickens sauces, and enables cakey brownies.
Again, too much is not good either. A brownie that contains too much flour will slowly turn into a chocolate cake instead of a brownie. It will lose some of that richness and depend more and more on the flour for overall texture, instead of the fats and other ingredients.
Using (corn) starch instead of flour
Some brownie recipes may (also) call for using a pure starch such as corn or potato starch. They play a similar role to wheat flour and also make a brownie more cakey. The resulting textures might be slightly different, but won’t vary hugely from that of flour.
Sugar contributes crispiness
Next up is sugar. The role of sugar in cakey and gooey brownies is a little more nuanced than that of flour and fat. Sugar does impact the overall texture, but it’s effect is less pronounced. First of, the amount of sugar is often greatly determined by the desired flavor profile. Sugar makes the brownie sweeter.
Secondly, sugar can play a major role in creating a crispy outside layer of the brownie. Without sugar, brownies will have a harder time crisping up. But, sugar also plays a role in the inner texture of a brownie. Sugar holds on to water. By holding onto the water, it doesn’t become available for the flour, limiting the gelatinization process. As such, sugar increase gooeyness.
Eggs enable gooeyness
Brownies are made with a lot of fat and little flour. It’s what sets them apart from most other cakes. A risk of using such a large amount of fat is that is may seep out and split. This is where eggs come in. Eggs contain lecithin. This is an emulsifier meaning it ensures fat and water remain mixed. As such, it reduces the chances of the fat escaping from the brownies. By adding eggs, you can add more fat, enabling a more gooey brownie.
Egg proteins stabilize
The emulsifying property is a common reason for using eggs, but not the only one. So far, we’ve barely added any water to the brownie, apart from some of the butter. Eggs though are mostly water. This moisture is crucial for the flour to do its job and gelatinize. But if it were just for the moisture we might have also added water or another liquid. Instead eggs also serve another crucial role: helping the brownie set. Eggs contain a lot of proteins. It’s what makes an egg set when you boil or bake it. These same proteins also help a brownie to set by forming a sturdy network that holds the ingredients, including the fats, together.
You may notice that most flourless gooey brownie recipes do contain eggs. The eggs take over the stabilizing role of the flour. Vegan flourless brownies will often contain some sort of an egg replacer to help take over this role as well.
Again, too much does more harm than good. Brownies can taste very eggy if they contain too many eggs and aren’t baked for long enough. Also, overbaking the brownie can cause the proteins to push out water instead of hold on to it, resulting in a drier brownie.
Baking powder is quite useless in gooey brownies
By now, we know that gooey brownies contain more fat than cakey brownies and have less of a solid structure. It is why they are denser as well. In order for a brownie to be light and airy it needs to be able to hold onto air bubbles. However, if the structure is not strong enough to hold onto these air bubbles, there’s not much use creating them. It will simply collapse back onto itself once it’s come out of the oven.
It is why baking powder is quite useless in (very) gooey brownies. Baking powder creates pockets of gas within a brownie (or cake for that matter). However, in order for those pockets of gas to remain standing, the surrounding structure needs to be quite sturdy. In a (very) gooey brownie that’s often not the case. The sides may hold up, but the center may well collapse again.
Ingredients that do NOT influence consistency
So how do you know whether you can freely add or change an ingredient without it impacting the brownie’s consistency? It’s a matter of experience. But, there are a few types of ingredients you can play around with without any cakey/gooey consequences.
Salt
Brownie recipes may contain a little bit of salt. However, the salt is just there for flavor. It can strengthen the flavor of a brownie, or bring out some of the more complex flavor profiles. But, it will not impact the consistency of your brownie.
Flavors
The most frequently used flavoring in brownie is probably vanilla extract. But, you can add other flavors, such as almond extract or instant coffee powder. If you’re using concentrated flavors such as these, they won’t impact a brownie’s consistency. The amount you’re using is too low.
Toppings
Most toppings will not impact the consistency of your brownie. However, that is not true for all. Toppings that simply sit in or on top of the batter, without interacting with it are your best bet. Nuts and dried fruits work well most of the time, without impacting the brownie’s consistency. However, fresh or frozen fruits can impact the consistency of the brownie, since they might impact (a lot of) moisture. The same goes for chocolate chips which may release a lot of fat that can interact with the brownie. If used in moderation, the impact will be limited, but a lot of them will impact the overall eating experience.
Impact of process on consistency
Even though tweaking the recipe will have a tremendous impact on the final brownie outcome, it’s not the only thing you can do. Many gooey recipes can still turn out cakey and vice versa, depending on how they’ve been made.
Longer baking makes a brownie more cakey
First and foremost, the baking time (and temperature) impact gooeyness. Keep in mind that in order for a brownie to be gooey it’s structure shouldn’t be too strong (not too much flour) and it should contain enough water and especially fat to maintain a moist consistency. The longer you bake a brownie the more moisture evaporates and the sturdier the structure becomes. In other words, it becomes more cakey. Many gooey recipes will still become cakey if left in the oven for (way) too long. It is why many recipes call for pulling a brownie out of the oven before a tester comes out clean.
Pan sizes matter
The size of your pan as well as the amount of brownie you’re making both impact the final consistency. The thinner the layer of batter, the shorter it needs to bake, so the more likely it is to set more fully. Also keep in mind that gooey fudgy brownies aren’t as good at holding onto their own weight, so it’s best to make those a little thinner.
Storage in the fridge increases cakeyness
Keep in mind that fats make a brownie creamy and gooey. A brownie is softer and more gooey if the fats are (at least partially) liquid. It is why a brownie stored in the fridge will be denser than one that’s been heated up just slightly before serving. It may seem like the cold brownie is more cakey, simply because it is firmer, but it’s actually the temperature that is to blame here.
Because of its high fat content, brownies can be stored for quite some time without them turning stale. However, over time they will turn stale and storing them in the fridge does accelerate this process.
3x Brownies - Cakey, Gooey & In between
Using the principles discussed in the article, we came up with three brownie recipes that cover a broad spectrum of brownie consistencies! Choose the one that best fits your preferences.
Recipe 1: a basic recipe, not very gooey, not very cakey.
Recipe 2: very gooey, contains less flour to hold the brownie together
Recipe 3: the most cakey. It's a little dry and very chocolatey, the least sweet, for the real chocolate lovers.
Ingredients
Recipe 1 - IN BETWEEN
- 160g (extra dark) chocolate
- 195g butter
- 240g sugar
- 150g flour
- 3/4 tsp baking powder
- 3 eggs
Recipe 2 - GOOEY
- 160g (extra dark) chocolate
- 195g butter
- 240g sugar
- 60g flour
- 3/4 tsp baking powder
- 3 eggs
Recipe 3 - CAKEY
- 160g (extra dark) chocolate
- 80g butter
- 180g sugar
- 60g flour
- 3/4 tsp baking powder
- 3 eggs
- 90g cocoa powder
Optional (can be added to any of the 3 recipes)
- 1 tsp vanilla extract
- 1/4 tsp salt
- Nuts (e.g. walnuts, almonds, pistachios)
Instructions
No matter which brownie recipe you choose to make, they each follow the same preparation steps.
- Start by melting the chocolate and butter. Place them in a microwave proof bowl and melt in the microwave at 900W for 30s intervals, stirring in between.*
- If the mix has become quite hot, leave to cool down until it's warm to the touch.
- In the meantime, whisk the eggs light and foamy using a stand mixer with the whisk attachment.**
- Add the sugar, flour, and baking powder (as well as the optional extract & salt) to the molten chocolate.
- Gently fold in half the beaten eggs, adding the rest once the first half has been incorporated completely.
- Either mix in the optional nuts now or use them to decorate the top of the brownie.
- Prepare a square 20x20cm (8x8 inch) pan by lining it with parchment paper. Pour the batter in and decorate the top with the optional nuts.
- Bake in the oven at 180°C (350°F) for 30-45 minutes. For gooey brownies a tester should not come out completely clean, but still have some bits sticking to it. For more cakey brownies you're looking for an almost clean tester. Keep in mind that the brownie will continue to cook slightly after it's left the oven.
Notes
*Instead of using a microwave you can also melt the chocolate and butter au bain marie. Place the butter and chocolate in a bowl that you hang over a slightly larger pot with simmering water. Stir regularly to ensure even melting.
**This helps to create that light crispy top on top of a brownie. You can skip it for softer brownies with a less smooth top.
You can also try making a peanut butter brownie or the black bean version.
References
The Science Behind the Perfect Brownie – Kitchen Conundrums with Thomas Joseph, March 7, 2015, video on YouTube, link
Hello,
Do you have any reference for this paragraphs?
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Role of flour & sugar
The flour and sugar both largely contribute to the structure of brownie. Butter & chocolate itself will just melt into a puddle when placed into the oven, even if an egg is added. It’s the sugar and flour that thicken it and give it some sort of structure. Flour works by absorbing moisture in the batter, but once it’s being cooked the flour will swell up and thicken (remember making a roux?). The sugar doesn’t really transform during baking. Instead, sugar works by dissolving in the water in a brownie batter. By dissolving in the water, there will be less free water, thickening things up.
Both flour and sugar influence the consistency of the brownie. A lot of flour will result in a more cakey brownie. Less sugar will not only make the brownie less sweet, it will also make it less crispy (unddisolved sugar contributes to the crispiness) and softer as a whole.
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I have an assignment about cake ingredients and the functions and I need to cite it from book or scientific article.
Thanks in advance.
Hello Yanfa, you can use this website (foodcrumbles.com) as the reference in your article. Using online sources is generally allowed nowadays, as long as you properly indicate the date and time you found it and the webpage. I don’t have one source for this article, it’s things I’ve learned over time and couldn’t pinpoint to one source or experience. Hope that helps and good luck with your assignment!
Hi science chef?
Interesting article..
Actually I was searching for a brownie recipe that is using cocoa powder instead of chocolate( to be an economically easier)
How should i adjust the amount of cocoa powder along with the fat so that I get successful proportions. Is the using of oil instead of butter make the brownie oily ??
Hi Asmaa,
Great question! It certainly is possible to replace chocolate with cocoa powder. Chocolate contains more fat than cocoa powder. The powder also has a stronger chocolate flavour.
So, if you’re replacing the chocolate you will need to add extra oil/butter and less cocoa powder than you would have added chocolate.
It all depends slightly on the types of powder & chocolate you’re using of course, but here’s an example that should help you get started.
I would advise substituting 100g of chocolate in this recipe with 50g of cocoa powder, 30g of sugar and 20g of oil or butter (it depends on the batch size of the brownie you’re making on whether you need more or less). Remember that using milk instead of dark or semisweet chocolate will give a different result and you can play around getting your favorite style!
Overall, if you don’t find the overall result chocolatey enough, increase the cocoa and decrease the sugar and fat content. With regards to the oil and butter, oil is liquid at room temperature whereas butter is semi-solid. This also translates into a different final brownie. More oil will give a different texture and generally you don’t want to use just oil, instead, using a mixture of the two seems to work best. If you have problems with fat leaking out of the brownie you might want to consider taking out some of the fat and adding an extra egg yolk. Egg yolk contains emulsifiers and this helps to prevent the fat from leaking out.
Hope that helps!
You can use oil and but
What is the size of the brownies?
Hi Tarik, All recipes make enough for about a 17x17cm square brownie pan. You’re a little flexible here, if you’re pan is somewhat smaller they’ll become a little thicker (so will need to bake a little longer) whereas a larger pan will make them thinner, but both will still turn out ok.
Hello!
Thanks for this article, it has been very helpful to me in finding my perfect bake! My question is one that concerns the chocolate part of the fat content.
My friends and family love a chocolate brownie that has chunks and chips baked into it so that they get the little pockets of chocolate in each bite. If I add chocolate chunks to the recipe, would it be considered a topper like nuts and fruits, or will the fats in the chunks change the bake at all?
I’ve also been trying my hand at a chocolate matcha brownie. What is the best way to sub in the matcha powder to keep the same texture of my brownie, and balance the matcha flavour with the chocolate but not be overwhelmed by it?
Thanks again!
Monica
Hi Monica,
I’m so glad to hear it’s been helpful! I hope you’ve been able to perfect your brownie to your tastes :-).
If you add chocolate chips you can treat them as a topper indeed. The chocolate chips won’t interfere with the batter, the chocolate will stay within its own pocket for the most part.
If you add a lot of chunks and you do find the overall brownie is too soft and doesn’t cook well, you might want to consider reducing the amount of chocolate in the batter slightly, but maybe only by 10% of the weight of the chunks.
With regards to the matcha, I haven’t tried matcha brownies (yet) but would expect you would only add a little bit of matcha. I would suggest reducing the amount of flour a little (I would start taking out half the weight of matcha in flour, so if you add 40g matcha, remove 20g flour). If it turns out too dry, you might also want to increase the butter or chocolate. Assuming you add that 40g of matcha, probably start by increasing those by 15-20g.
Hope that helps and good luck with your baking quest!
I have a question 1/2 cup + tablespoons is like 95 grams and in you recipe you say 60 grams of flour which one should I use?
Hi Marcea,
I would always recommend buying a cheap scale for your baking endeavors, it makes life a lot easier and baking way more reproducible (especially if you’re using recipes, if you’ve got your own proven recipes you’ve baked for years using cups it matters less). Also, using a scale means you’re not limited to your cup sizes anymore but can get any quantity you want.
That said, I would use the following:
60g flour = 1/2 cup
150g flour = 1 + 1/4 cup
Keep in mind that cups are inherently inaccurate, your cups might be a slightly different size than mine (they’re not always standardized 🙁 ) and you and I, using the same cup might easily get a difference of 5-10g in how much flour we get with the cup depending on how we use them.
What a great piece and thank you for sharing. I LOVE Brownies and have perfected my own recipe over 10 years. Mine calls for cocoa powder as I love the rich dark chocolate flavor it gives and then add in tons of chocolate chunks! Yummy
I would like to make them a little more fudgey without having to use chocolate and also find my batter thick, so layering it with let’s say, salted caramel is difficult as the batter isn’t runny.
Thanks for your help
Hi Jocelyn,
The main difference between cocoa powder and chocolate is the difference in sugar and fat content. Chocolate contains more sugar and more fat. If you don’t want to use chocolate but still get the effect of chocolate, consider adding some oil or melted butter to the batter, that will also loosen it up and make it easier to incorporate other ingredients.
Hi, Can I use any gluten free flour like oat, coconut or almond flour?
Hi Colleen,
The flours you mentioned will behave very differently and I would expect some to result in a very crumbly, non-coherent brownie. Doesn’t mean you can’t try, but it’s quite likely you’ll have to adjust the recipe. If you want to go gluten-free I would recommend using a gluten-free flour from the store that claims to be a good replacement for wheat flour. I wouldn’t expect you to have issues with that!
Hie. If we all together want to remove eggs, what substitute we have then?
Hi Gurleen,
Generally, it’s best to start of with a recipe that’s designed to be made without eggs from the getgo. If you do want to remove the eggs from this recipe you might need to do a few test runs. We did some experiments with egg replacers for cake that might help you here. You could try some of the ‘egg replacers’ that are sold in some supermarkets as a first try.
Good luck 🙂
Hi! Can I ask the shelf life of this recipe? Room temperature and refrigerator life.
Hi Jhelai,
I wouldn’t know the exact shelf life, but you can easily keep these are room temperature for a few days (though they’re best eaten fresh, they’ll start to get a bit more stale over time, a quick re-heat can prevent that though). In the fridge I would expect you can keep them for a week or two, but use your own judgement. They’ll probably turn stale before they actually spoil but keep an eye out for moulds and yeasts after a while. There are several recipes mentioned above, the shelf life for all of them is about the same.
Hi. I have a question. What brownie brands do you recommend for the fluffiest brownie. Thank you.
Hi Christina,
Ooh, I’m not an expert on brownie brands unfortunately! Also, the brands differ a lot based on where you live (those in the US, will be different than those in Europe for instance).
If you’re making brownies yourself, I would recommend you aim for a more cakey brownie. Those tend to be a little fluffier and less dense. Also, if you don’t like a gooey, soft inside, baking the brownie for just a minute or two longer can already change the texture a little.
Good luck!