The science behind Chocolate Cake | Part II

By Chef David “Smitty” Smith  ·



Editor’s Note: Part I may be found at

Last week, I talked about why you need to adjust a cake recipe in order to get it to work at high elevation. As a quick summary, the basic reason is air pressure. With less air pressure, water boils at a much lower temperature causing it to evaporate sooner and taking longer for things to cook. Without changes to the recipe, the batter doesn’t have time to thicken before the liquid evaporates and your cake will often fall and/or be dry.

The basic rules in adjusting your recipe are to reduce the amount of leavening agents and sugar while increasing the amounts of liquid and sometimes flour, while also raising the oven temperature by 15 to 25 degrees.

I’ve included the original recipe along with the adjusted recipe. The one thing I do is substitute Dutch processed cocoa for the regular cocoa.

As you can see, there are three items – milk, water and eggs (I used extra large instead of large) – that were increased and two items – sugar and baking powder – that were decreased. I also didn’t need to change the amount of flour or the oven temperature (I did start checking on it slightly earlier, but it seems to take the same time). I did try making this cake several times, making small adjustments to different ingredients, with some of the other tries working well, but this just seemed to be my favorite.

OK, so as you can see, the original recipe called for cocoa and in my recipe I used Dutch processed cocoa. The difference is that cocoa is made by roasting the cocoa beans and then grinding them to a paste. The paste is then pressed between hydraulic plates, which squeeze out about half of the cocoa butter or fat that is in the beans. After this, it is grated to the fine powder you buy it in.

In natural cocoa, there is a high acidic level. When they Dutch process the cocoa, they first wash the beans in a potassium solution that neutralizes that acidic level of the natural cocoa. Then they pulverize the beans into a powder. Dutch processed cocoa will appear much darker than natural cocoa, but doesn’t mean it is richer flavor, but rather it is a mellower flavor due to the reduced acidity level.

They say you cannot randomly interchange one for the other. Because of the lower acidic level of the Dutch processed cocoa, it won’t interact with baking soda like natural cocoa. This is something I didn’t realize when I made my substitution.

I think it works in this recipe because the recipe has both baking soda, as well as baking powder. Also, because the recipe calls for boiling water, I think that blooming of the cocoa also helps.

Now, I have to say, if you are thinking about using Dutch processed cocoa, look at the ingredients first to be sure there is baking powder and not just baking soda. This is another reason that makes baking a more refined science than normal cooking. It really does matter what you use, what you do with these ingredients, and how you do it. Ah, isn’t science awesome.

Original recipe     
2 C sugar
1¾ C all purpose flour
¾ C cocoa
1½ t baking powder
1½ t baking soda
1 t salt
2 eggs large
1 C milk
½ C vegetable oil
2 t vanilla extract
1 C boiling water

Adjusted recipe
2 C sugar, minus 5 T
1¾ C all purpose flour
¾ C Dutch processed cocoa
1 1/8 t baking powder
1½ t baking soda
1 t salt
2 eggs, extra large
1 C milk, plus 3 T
½ C vegetable oil
2 t vanilla extract
1 C boiling water, plus 3 T

Smitty is a personal chef specializing in dinner parties, cooking classes and special events. Trained under Master Chef Anton Flory at Top Notch Resort in Stowe, Vt., Smitty is known for his creative use of fresh ingredients. He has been a chef for PGA’s Memorial Tournament for more than 15 years and ran the main kitchen at the World Games. For more information and archived copies of Stir it Up, visit Smitty welcomes questions and comments at [email protected], [email protected] or (530) 412-3598.