Cut to a few months ago, when I am asked by my very sweet Godmother to make a cake for her daughter's surprise 30th birthday party. Her favorite cake favor? Of course, it's red velvet. So I broke my vow and made it once more. This time, I'll admit, I used a box cake mix. After striking out so badly with a scratch recipe, and it not being one I had the interest to perfect, I thought I'd be better served piggy-backing on the years and time that Duncan Heins had put into its product development. Honestly, the only difference I can tell you is that it didn't stain my mouth. It was still a boring, blah, bitter, tasteless mound of red cake. Its only saving grace is its smooth texture, and of course, homemade Swiss meringue cream cheese buttercream. Yum. I once again vowed to never make red velvet again.
Cut to this past weekend. I'm flipping through the King Arthur Flour catalog, when I saw Cocoa Rouge. It intrigued me because I remain mystified by red velvet's popularity. I thought maybe, just maybe, this is the secret. I started researching the origins of red velvet cake, and frankly, there isn't much information out there. And what is available, is often conflicting. There are a range of theories, from the development of red velvet as spice industry's ploy to increase sales of food coloring, to a $300 dollar cake at the Waldorf-Astoria hotel in the 1940's. It seems, when it comes to the origins of red velvet cake, you just need to pick a theory that you are most happy with. I'm going with history, science and dash of common sense.
According to New York Times food writer Kim Severson, red velvet cake dates back to the 1800's. Commercial food dye did was not allowed by the FDA until 1938. So, using a little common sense, it's easy to conclude that the first red velvet cake recipe did not include an obscene amount of red food coloring. So where did the red color come from? My personal theory is that the development of red velvet came by accident (as many recipes do!). And this is where we look to science for the answer.
Before understanding why red velvet is red, lets understand why red velvet is velvet. Traditional red velvet cake calls for baking soda and a good amount of some type of acid - white vinegar and/or buttermilk. Remember that volcano you made for your 5th grade science fair? That was baking soda and vinegar mixed together to create an acid-based reaction that produces carbon dioxide. The same "eruption" happens when you mix them in your cake batter, only this time the air bubbles are used to give the cake its soft, fluffy & velvety texture.
So now that you know the basis for its velvety texture, you can understand how it accidentally became red. It's actually quite simple. Natural cocoa powder has a naturally red tint. Natural cocoa powder contains anthocyanins, which are the same compounds that put the blue in blueberry, the black in blackberry, and so on. They are also very sensitive to acid, and when exposed to acidity (like the vinegar and/or buttermilk in the red velvet recipe), the color of the anthocyanins deepens. (Try dipping a leaf of red cabbage into a bowl of vinegar and you'll see it for yourself.) It is my belief that this chemical reaction was enough to give the cake a red hue, albeit not the vibrant red we expect today, and thus the birth of red velvet cake.
Today, the cocoa powder you have in your pantry is most likely Dutch Processed cocoa powder, which is an evolution in the production of cocoa powder that came about in the mid 1800's (by a dutch chocolatier) to make cocoa powder more water soluble and easier to bake and cook with. The "dutch process" lowers the acidity of cocoa powder, which in turn, removes most of its anthocyanins. This is why today's cocoa powder does not produce the same red hue, and thus the need for gross amounts of red food coloring to compensate.
For now, I'm not making any new vows to never again make a red velvet cake. Instead, I vow that if I offer red velvet as a cake flavor option, it will only be because I have found a way to make it taste good (even if it's not bright red).
End rant.