Mission bakers agree, people love red velvet cupcakes.
Regardless of whether the handsome red desserts are purchased on the street from Sweet Construction’s cookie cart or in miniature at Mission Minis, red velvet is quite possibly the region’s most popular cupcake flavor.
It could be the velvety texture, enhanced by the chemistry of buttermilk, which makes a fine crumb. Or perhaps it’s the cream cheese frosting, although that’s used only on more modern red velvet cakes – old-fashioned ones have butter cream frosting.
Or maybe it’s the seductive red color, emotionally appealing even though it has a negligible relationship with the cupcake’s flavorings.
“People enjoy food with their eyes,” said Christine Bruhn, a food scientist at UC Davis. “It’s part of the total package.”
Contrary to the wishful eating of some cupcake consumers, there’s no cherry or raspberry component in red velvet. There is a lot of food coloring– this recipe has six times as much food dye as chocolate powder – and whatever flavors result from the chocolate, vanilla, buttermilk, sugar, flour, and eggs.
Red velvet’s intense color is a purely visual experience.
Science tells us that people look for red in foods, even believing that more intensely colored foods actually have more flavor and a stronger aroma.
Furthermore, we prefer redder foods, for example, peaches with a red blush.
In pre-industrialization orchards, a pink blush on a peach indicated a sweeter fruit, because peaches that ripen in sunnier spots are sweeter, and the same peaches develop a pink blush from extra sun exposure.
Consumers prefer pinker peaches, presumably thinking they’re getting sweeter fruit. So today, producers have bred peaches to have a blush, regardless of whether they ripened in the sun, according to Bruhn.
However, there are plenty of sweet, flavorful peaches that are yellow, and Bruhn suggested a better metric for judging sweetness is the lack of green, rather than the presence of rosiness.
“If there’s a red peach with green on it, growers have found people will actually pick it,” Bruhn said.
Studies have shown people look to visual cues to fill out their flavor information.
“In default of having the complete story, we make certain assumptions,” said Tom Neuhaus about red velvet’s allure. Neuhaus is an associate professor of food science at California Polytechnic State University, San Luis Obispo.
“Certainly it’s not blood, so it must be some sort of red fruit. Who would put tomatoes in a cake, so it must be cherries,” he said, engaging in a little pop psychology.
A 1995 studyi showed that older subjects – between 60 and 75 years old – thought fruit drinks had more intense flavor if they were darker, even though the drinks had the same amount of flavoring.
Furthermore, the same study found people of all ages tended to guess that a cherry-flavored drink was cherry-flavored only if it looked red. Subjects tended to think the cherry drink was orange-flavored, or didn’t recognize the flavor, if it was yellow in color.
“Color is important for more than appearance. Color obviously provides cues which cause interactions with perceptions of other sensory characteristics (as do taste and flavor),” conclude the study’s authors.
It is possible that the red velvet’s hue had a natural origin. Dutch process cocoa is alkalized to neutralize the pH of naturally-acidic cocoa. Some cooks have theorized that low-quality cocoa could be so far alkalized that it might turn reddish in a cake. It’s the same chemistry that makes an Oreo cookie black, according to Neuhaus.
However, Neuhaus has an unrelated theory why the cake is so popular. It’s the superior texture, which comes from using buttermilk—or, as he puts it, “fake buttermilk.”
“The buttermilk in the store has absolutely nothing to do with butter,” Neuhaus said. Real buttermilk is the watery leftovers when cream is churned to butter. It’s not whitish, it doesn’t have flakes of butter, and it isn’t very sour.
That’s unlike today’s store-bought buttermilk, which is white – from the caseine – and about as sour as yogurt.
However, the two buttermilks have one thing in common, an emulsifying protein that reduces the tension between fat and water.
When butter or shortening is creamed for cake batter, air gets trapped in the fat. Sugar in the cake batter binds water, which doesn’t mix well with those fat molecules.
Enter the buttermilk. Its emulsifying protein stabilizes the water and the fat in the batter. That means smaller air cells trapped by the fat can withstand the high temperatures of baking without tunneling out of the batter. The result is a finer cake crumb, according to Neuhaus.
i. Philipsen D.H., F.M. Clydesdale, R.W. Griffin, and P. Stern. Consumer age affects response to sensory characteristics of a cherry flavored beverage. Journal of Food Science, 60:364-368, 1995.