August 22, 2013
G had a mystery. Her gluten free cupcakes kept sinking in the middle. They were beautiful when they came out of the oven. But, turn your back to get the icing from the refrigerator*, and they’d quickly do their best impression of a dormant volcano. She emailed me to see if I could help her figure out why these sneaky cupcakes kept foiling her attempts at a perfect gluten free dessert.
OK, here are some pics of my cupcakes..you can see that they look all nice in the oven but fall in the middle after I get them out. I did use a few tweaks in my recipe yesterday but it doesn’t matter…this is still pretty typical of how my cupcakes look. Can you help? ~G
What do you do when a recipe doesn’t work and you have no idea why?
The first thing that I want to do is take a look at the recipe as a whole. I had G send me the recipe – in grams. Recipes are mathematical. If you want to understand them, then you have to look at the relative weights of ingredients, and you can’t do that if the recipe is written in cups and teaspoons.
Once the recipe was in grams I completely geeked out! I threw the recipe into a spreadsheet and analyzed the relative quantities of various ingredients. I also compared it to a similar cake recipe of mine that I knew was a sound.
This analysis made two things very clear.
1. G’s recipe was overleavened….by 233%
2. Her recipe contained much less fat than my recipe
I emailed G and explained my findings:
I just did a ratio analysis of your cupcake recipe and two things stand out to me. First, your recipe is overleavened. Baking soda is 4x as strong as baking powder, so 9 grams of baking powder + 3 grams of baking soda = 21 grams baking powder. The 9 grams of baking powder should be sufficient by itself to raise the cupcakes.
Try that change by itself first and see how it goes.
The second thing that I noticed is that your cake seems rather short on fat. I’d be perfectly comfortable using up to 175 grams of fat, especially since you’re using whole eggs rather than egg yolks only. ~ Mary Frances
By the next morning I had a reply in my inbox.
OK, I took your suggestions…and LOOK! They look the same as they did when they came out of the oven! And the texture is nice and pillowy…soft, yet dense enough to not fall apart. Not gummy! Thanks SO much for your help…I think that did it!!! ~G
*I do realize that you wouldn’t spread icing on cupcakes right after they came out of the oven. That would be silly. But, that doesn’t mean that you can’t have a spoonful of icing while you contemplate the beauty of your still-hot cupcakes!