Gluten-free baking can be tricky, especially when it comes to baked goods that need to rise, like cakes. Gluten provides structure and elasticity in typical baking, allowing dough to trap the air bubbles produced by leavening agents like baking powder or baking soda. This air allows the batter to rise when baked, resulting in a light and fluffy texture. Gluten-free flours lack this protein, so alternative strategies must be used to give lift and rise to gluten-free cakes. This article will explore the science behind leavening and rising, analyze the properties of various gluten-free flours, and explain techniques home bakers can use to create gluten-free cakes with good rise and structure.
The Science of Leavening
Leavening refers to the process of incorporating gas bubbles into a baked good to make it rise when heated. This rise in volume produces a soft, porous texture in the final product. The main leavening agents used in baking are:
– Baking soda (sodium bicarbonate) – When this is combined with moisture and an acidic ingredient like lemon juice or buttermilk, carbon dioxide gas is produced. The bubbles of this gas get trapped by the structure of the batter, causing it to inflate as it bakes.
– Baking powder – This contains baking soda plus an acidic component like cream of tartar. It creates carbon dioxide bubbles immediately when liquid is added, without requiring a separate acidic ingredient. Double acting baking powder also contains a second acid that continues producing gas during baking.
– Beaten egg whites – Whipping egg whites incorporates tiny air bubbles that will expand when heated to leaven baked goods like sponge cakes and soufflés. The protein structure of the whipped whites helps stabilize these air pockets.
– Steam – Water converts to steam when heated, which can add lift to batters like popovers and choux pastry. Starches help set these structures so they don’t collapse when the steam escapes.
Gluten’s elastic strands trap and hold the gas bubbles produced by chemical leavening or air incorporation, allowing them to inflate the batter from the inside. Gluten-free batters lack these strands, so the bubbles tend to escape rather than lifting the batter. Preventing this escape is key when leavening gluten-free cakes.
Properties of Gluten-Free Flours
While wheat flours contain gluten, alternative gluten-free flours each have their own properties that affect how they can be used in baking. Understanding these unique characteristics is important for creating successful gluten-free cakes.
Rice Flour
Rice flour is made from finely milled rice grains. It has a neutral flavor and fine, powdery texture. Rice flours contain mostly starch with a small amount of protein, so they form a light crumb but have little structure. Cakes made with just rice flour tend to be gummy and dense rather than fluffy. Rice flour is often blended with other flours and used at lower proportions.
Sorghum Flour
Sorghum flour has a mild, slightly sweet flavor. The texture of the flour itself is grittier than other gluten-free options. Sorghum contains starch and protein that can help provide some lift and structure to baked goods. Too much sorghum flour can result in a dense texture, so it’s usually combined with other flours.
Arrowroot Starch
This very fine white powder acts as a binding agent and helps create a lighter crumb. Arrowroot doesn’t provide much rise on its own, but it allows more lift from leavening agents by preventing dough from becoming too dense. A small amount of arrowroot starch is useful for lightening the texture of gluten-free cakes.
Tapioca Flour
Also called tapioca starch, this flour provides chewiness with a mild, slightly sweet flavor. Tapioca flour is made from the starchy root of the cassava plant. It has more binding capacity than structure-building ability, making it useful when blended with other flours. Tapioca flour helps improve the texture of gluten-free baked goods.
Almond Flour
With a pleasant nutty richness, almond flour consists of ground almonds so it contains protein and fat along with starch. This can help provide more structure than starches alone. However, batters made solely with almond flour tend to be heavy. Combining almond flour with lighter starches creates a better balance.
Coconut Flour
Coconut flour is high in fiber and absorbs a lot of liquid. It has a sweet coconut flavor that works well in cake recipes. Due to its absorbency, coconut flour binds ingredients well but can result in dense textures when used alone. Combining it with lighter starches prevents this density.
Techniques for Gluten-Free Cake Rising
While gluten-free flours on their own don’t trap air as well wheat flour, home bakers can use several techniques to help their gluten-free cakes rise properly:
Blend Flours
Using two or more alternative flours creates a better balance of binding power, structure, lift, and lightness compared to a single flour on its own. Some good gluten-free flour blends for cake baking include:
– Rice flour, tapioca flour, and potato starch
– Sorghum flour, arrowroot, and almond flour
– Coconut flour, chickpea flour, and cornstarch
The exact proportions will vary by recipe, but blending flours based on their individual properties results in a more well-rounded flour mix.
Increase Binding Agents
While gluten provides cohesion and elasticity in standard cakes, gluten-free bakers can add extra binding agents to mimic this role. Ingredients like xanthan gum, guar gum, flax seeds, and chia seeds are useful binding agents. They improve the structure of batter to help support rising.
Use about 1/2 to 1 teaspoon of xanthan or guar gum per cup of flour. If using flax or chia, grind the seeds finely and add 1 to 2 tablespoons per cup of flour. Don’t overdo the gums or the cake can become gummy. Test different proportions to see what works best.
Handle Batters Gently
Vigorous mixing or beating incorporates too much air into delicate gluten-free batters. This can cause bubbles to pop and batter to deflate. Gently fold wet and dry ingredients together with a spatula just until combined. Avoid over-mixing.
Let Batters Rest
After mixing together a gluten-free cake batter, allow it to sit and hydrate for 5 to 15 minutes before baking. This allows the flour to fully absorb moisture and gives starches time to develop structure. Leavening agents can also begin producing early gas bubbles during this rest.
Use Careful Box Folding
The classic cake baking method of “box folding” is especially useful for sturdy gluten-free batters. Instead of stirring vigorously in a circular motion, run the spatula along the sides and bottom of the bowl to fold batter from the outside inward gently. This prevents deflating air bubbles.
Don’t Over-Fill Pans
Gluten-free cakes need room to rise properly, so fill the cake pan only halfway to two-thirds full. Pans that are over-filled won’t allow the batter space to increase in volume, resulting in undesirable doming or overflow.
Use Pan Supports
Placing cake pans on a baking sheet or pizza stone rather than directly on the oven rack allows for air circulation underneath. This promotes even rising by preventing a dense bottom crust from forming.
Bake at Lower Temperatures
High heat can cause gluten-free cakes to set quickly before having time to rise fully. Bake around 300 to 325°F instead of 350°F to allow gradual rising without over-browning. Test doneness with a toothpick.
Cool Cakes Upside Down
Flipping pans over after baking so the cake rests upside down on the pan top allows moisture to distribute evenly while cooling. This prevents crumbly texture and shrinkage cracks. Leave inverted until completely cooled before removing from the pan.
Recipe Example: Moist Gluten-Free Vanilla Cake
This simple vanilla cake recipe produces a nicely risen and tender crumb using a blend of gluten-free flours plus leavening techniques:
Ingredients
– 1 1/4 cups (150g) white rice flour
– 3/4 cup (90g) sweet rice flour
– 1/2 cup (60g) tapioca flour
– 1/4 cup (35g) granulated sugar
– 2 teaspoons baking powder
– 1 teaspoon xanthan gum
– 1/2 teaspoon salt
– 2 large eggs, room temperature
– 1 cup (240ml) unsweetened almond milk
– 1/3 cup (75g) neutral oil or melted coconut oil
– 1 tablespoon lemon juice
– 1 1/2 teaspoons vanilla extract
Directions
1. Preheat oven to 325°F. Grease an 8-inch round cake pan (or line with parchment).
2. In a medium bowl, whisk together the rice flours, tapioca flour, sugar, baking powder, xanthan gum, and salt.
3. In a separate bowl, whisk together the eggs, milk, oil, lemon juice, and vanilla until blended.
4. Pour the wet ingredients into the dry ingredients. Gently fold together with a spatula just until combined (do not overmix).
5. Pour the batter into the prepared pan, smoothing the top lightly (do not press down).
6. Bake for 30-35 minutes until golden on top and a toothpick inserted in the center comes out clean.
7. Cool the cake pan inverted on a wire rack until completely cooled, about 1 hour.
8. Run a butter knife around the edges of the pan and invert onto a plate or cake stand to unmold.
The blend of rice and tapioca flours provides structure, as does the xanthan gum binding agent. Gentle folding prevents deflating air bubbles from the chemical leavening. Baking at a low temperature allows the cake time to rise fully before the structure sets. Cooling upside down gives an even crumb. The result is a nicely risen and tender vanilla cake!
Troubleshooting Gluten-Free Cake Issues
Even when using proper techniques, gluten-free cakes can still sometimes have problems. Here are some common issues and potential solutions:
| Issue | Potential Causes | Fixes |
|---|---|---|
| Cake falls or deflates | Overmixing, moving pan, baking at high heat | Gently fold batter, avoid jostling pan, lower oven temperature |
| Dense, gummy crumb | Too much liquid, underbaking, incorrect flour balance | Reduce liquid slightly, bake longer, adjust flour ratios |
| Cracks on top | Batter too thick, oven door opened too soon,incorrect pan size | Add a bit more liquid to batter, don’t open oven early, use recommended pan size |
| Sunken center | Over-filled pan, incorrect oven rack position | Fill pan no more than 2/3 full, use middle rack position |
| Burnt edges | Baking at too high temperature | Reduce oven temperature 25 degrees |
Conclusion
Baking light and tender gluten-free cakes is very doable with the right understanding and techniques. Using an appropriate blend of gluten-free flours provides structure and binding. Gentle handling prevents deflating air bubbles from leavening agents. Allowing batters to rest hydrates the flours fully. Low baking temperatures give time for the cake to rise before setting. Cooling cakes inverted distributes moisture evenly. Troubleshooting issues like sinking or density involves adjusting ingredients, pans, and methods accordingly. With practice and a few simple tricks, home bakers can whip up gluten-free cakes with delightfully airy and fluffy results.
