Cravings of a Food Scientist

Do Betty Crocker and Duncan Hines account for human error? I’ve often wondered if one could truly mess up a boxed cake mix. Baking is much more of a science than cooking, and your technique really matters (just ask my boyfriend, he’s slowly learning 🙂 ) So I decided to put it to the test. What would happen if I intentionally botched my technique?

Daydreaming of cake

To answer this question, I designed a sweet experiment. And, as any good scientist should, I developed a hypothesis: under-mixed cupcakes will be lumpy and weak, while over-mixed cupcakes will be dense and chewy. However, the differences are unlikely to make a big difference for the average baker. 

To test my theory, I used a standard boxed cake mix: Betty Crocker Delights Super Moist Carrot Cake Mix. There was no rhyme or reason behind this choice or brand, I just really wanted some carrot cake 🙂

I followed the recipe instructions exactly as written. Preheat the oven and mix the ingredients: water, vegetable oil, and three eggs. Pretty straightforward.

To test the variable (mixing time), and control for any other factors, I used the same batter throughout the process. I first gently mixed the batter with a spatula until all ingredients were just combined, about 30 seconds, and filled six cupcake cups. Next, I used speed 2 on my KitchenAid stand mixer to mix the batter for 2 minutes and filled six more cupcake cups. This sample was used as “control.” Finally, I continued mixing the remaining batter for a total time of 5 minutes and 30 seconds, more than double the recommended mixing time. Cupcakes were baked for a total of 19 minutes and allowed to cool completely before analysis.

A Little Cake Science

Cupcakes and other pastries contain pastry flour, which contains the dough strengthening protein gluten. However, pastry flour contains the lowest amount of gluten protein as compared to other types of flour. This allows cakes to be soft and tender, rather than structured and firm, like bread. As I’ve explained in previous posts, here and here, gluten is formed via the combination of proteins glutenin and gliadin and mixing. So it makes sense that the more you mix the batter or dough, the more protein and more structure you create.

In dough products like bread, yeast is often the catalyst for leavening, or rise. In products like cakes and cookies, however, there are some other things going on. When you’re mixing batter or creaming together butter and sugar, you are actually performing a critical step; that is introducing air into the batter. This is known as mechanical leavening Baking soda and baking powder are also ingredients used to create leavening, known as chemical leavening. In the case of this cake mix, baking powder is used, listed on the label as: baking soda, sodium aluminum phosphate, and monocalcium phosphate.

What’s the difference? Baking soda’s chemical name is sodium bicarbonate. It requires an acid in the recipe to produce carbon dioxide in the presence of heat and moisture. These bubbles expand and provide leavening during baking. Baking powder is actually just a combination of baking soda plus the required acid (and starch), all in one ingredient. Most baking powders used in cake baking are double acting, meaning they first release gas as the come in contact with the liquid batter, and then continue to produce more gas once they reach higher temperatures in the oven. Each of these ingredients produce carbon dioxide in the cake batter, just as yeast does in bread. They provide leavening and tenderness to baked products.

Keep in mind that while the directions for Betty Crocker cakes are pretty simple, just mix and bake, it’s not that easy in commercial bakeries. There are may different batching and mixing methods used to produce very specific textures and types of cake. (Thus the origin of my question today)

So, now we know the ingredients to make a delicious, tender cake. Most importantly, air! Here’s a little recap:

• Pastry flour ensures a soft structure
• Baking powder provides chemical leavening and crumb tenderness.
• Mixing the batter introduces air and disperses/hydrates all ingredients
  • Too much mixing may over-develop the gluten, leading to a less tender crumb
• Fat, in this case vegetable oil, also ensures a soft, tender crumb by disrupting the gluten structure.
• Eggs act as emulsifiers and binders to suspend fat ( creating an oil in water emulsion) and air bubbles (creating a foam, or air in liquid “emulsion”) in the batter

Got it? Good! Now, on to the results!

Batter Results

Overall, the biggest differences in the batter were in lumps and air bubbles. In terms of viscosity, the under-mixed product resembled lumpy muffin batter, while the over-mixed batter was very runny.

For most bakers, I think it would be pretty apparent the under-mixed batter wasn’t yet ready. I think the potential problem lies in over-mixing. Maybe you’re an over-achiever and just really wanted to make sure you end up with the best cupcakes ever, or maybe you got distracted and left the mixer running while you chased after the dog, either way user-error is pretty likely in our everyday lives.

Final Results

Crumb & Texture

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Why? It all comes down to air.

Over-mixing leads to over-aeration. The air cells have essentially expanded so much they become weak and collapsed, leading to the dense texture.

In the under-mixed sample, the ingredients were not well dispersed and air was not incorporated uniformly. Because the water in the batter was not able to properly dissolve all the dry ingredients, instead it evaporated during baking. Without enough air in all the right places, you end up with a lot of large holes, which can lead eventually lead to “tunneling” or the very large holes you may see in the crumb of some cakes (or even breads).

Taste

To be honest, all these cakes were delicious! I noticed more sweetness in the control sample as compared to the other two. I believe the the more moist and textured crumb of the under-mixed sample took away from the flavor a bit. However, my boyfriend ate all three cupcakes and noticed no differences between any of them, other than increased moisture in the under-mixed sample, sooo there you have it. It’s unlikely anyone will notice these small differences.

Although, I did bite into an especially eggy-tasting piece of one of the under-mixed samples. It wasn’t bad, but definitely wasn’t what I was expecting. So, it’s definitely wise to make sure your egg is fully incorporated.

Conclusions

After icing and sprinkles? Not much difference in flavor or texture.

My final thoughts: Yes, boxed cake mixes are pretty much foolproof. Even if you under or over mix by a bit, you’re probably still going to come out with a delicious cake, especially after you top it with some delicious icing. Hey, maybe you even like a denser cake!

So now you know. There’s one less thing to stress about. (although cake should never cause stress)

Do you have any other kitchen questions? Let me know!

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References

Pyler, EJ, Gorton, LA. 2009. Baking science and technology. Volume II: Formulation and Production. 4th Ed. Sosland Publishing. Kansas City.