Published November 1, 2012. From Cook's Illustrated.
These days cocoa powder fetches anywhere from $7 to nearly $24 per pound. But is price any indication of rich chocolate flavor?
Cocoa powder is a chocolate powerhouse, packing in more flavor ounce for ounce than any other form of chocolate. In the test kitchen, we reach for it constantly when making cookies, cake, pudding, hot chocolate—even chili—which is why we’re picky about what brand we keep around. When we last tasted cocoa powders, in 2005, the supermarket cocoas produced such insipid results that we reluctantly resorted to sending away for the one brand that boasted real chocolate flavor and depth: Callebaut, which also rings in at a whopping $16 per pound (and that's without shipping).
But given that all chocolates (milk, bittersweet, unsweetened, etc.) have witnessed an upgrade in recent years, we wondered: Have supermarket cocoa options improved as well? Furthermore, several higher-end brands, such as Valrhona and Scharffen Berger, can now be found in many markets nationwide. That was all the convincing we needed to revisit the category. We didn’t want to sacrifice quality for convenience, but if we could identify a brand that delivered the deep chocolate flavor we were after without the prohibitive cost or waiting for the postman, we’d happily make the switch. Pretty soon we were baking up a storm, incorporating eight widely available brands of cocoa into chocolate butter cookies, chocolate cake, and hot cocoa. As they evaluated the samples on the intensity and complexity of the chocolate flavor, tasters reconfirmed that the brand of cocoa you use really does make or break a dessert or a drink. Lesser powders produced “wan” cakes and hot cocoa that tasted like “dust dissolved in water”; good versions delivered “profound” chocolate flavor and made cookies seem downright “luxurious.”
At first we thought that differences might have to do with whether the cocoa was natural or Dutch-processed. Dutching, which was invented in the 19th century by Dutch chemist and chocolatier Coenraad Van Houten, raises the powder’s pH, which neutralizes its acids and astringent notes and rounds out its flavor. (It also darkens the color.) But according to our numbers, whether a cocoa was Dutched didn’t matter. Our winner was a natural powder, and there was no pattern to the rest of the rankings.
Fat content also seemed like a potential factor in the rankings. Cacao beans naturally contain 47 to 54 percent fat, and how much of that fat is retained after processing is a bragging point for many higher-end brands of cocoa. More fat suggests a richer-tasting product, and pricier brands often contain twice as much fat as do standard powders. But again, our preferences proved those assumptions wrong. Both our first- and last-place brands contained nearly the same low level of fat (about 11.5 percent), and in between those extremes the levels jumped up and down.
With pH and fat out of the running, we took a step back to remind ourselves of the main feature dividing the pack: bold, rich chocolate flavor. The top-ranking brands had it, the bottom-ranking didn’t. To understand why this would be so, maybe we needed to answer a more fundamental question: Where does chocolate flavor come from, anyway?
The Whole (Bean) Story
It starts with the cacao pod—the football-shaped fruit of a stout tropical tree, Theobroma cacao, that grows below the jungle canopy in humid climates 20 degrees north and south of the equator, a swath of land sometimes referred to as the “Cocoa Belt.” Each pod contains 20 to 50 beans, and inside each bean are the nibs—the dark, meaty flesh that is ground and later refined to make chocolate. When harvested, the pods and their contents neither smell nor taste like chocolate (in fact, the white flesh surrounding the beans is said to taste like a combination of watermelon, strawberries, and kiwi). After harvesting, the beans are left to ferment, a process that eats away at the fruity flesh surrounding the beans and initiates the development of flavors that are recognizably chocolaty. The beans are then dried, bagged, and sent to a processing facility to be roasted.
This is the most exacting—and critical—phase of the process. Roasting triggers the Maillard reaction, in which proteins and sugars in food break down and develop more complex flavors. In cacao beans, this means the potential for nearly 500 new flavor compounds to be formed. To achieve this, manufacturers roast beans within the same relatively low temperature range following one of two methods: They either roast the beans whole and discard the shell after roasting (the traditional approach), or they remove the shell and roast just the nibs. To further develop flavor, chocolatiers often blend beans during roasting, mixing nibs and powder from various origins (manufacturers wouldn’t reveal their bean sources to us) to achieve the exact specifications of color, texture, and flavor. During the final phases of roasting, some chocolatiers even carry out taste checks on the beans or nibs, scooping them from the roaster at 15-second intervals to nail down the exact point at which they believe flavors are optimized.
Figuring that the roasting phase of the process might shed some light on our cocoa preferences, we contacted all eight manufacturers to inquire about their methods and, sure enough, uncovered a pattern: The top brands in our lineup separate the nibs before roasting, while lower-ranking brands roast the whole bean, shelling afterward. According to Gregory Ziegler, a chocolate expert and professor of food science at Pennsylvania State University, roasting just the nibs offers a distinct advantage: The nibs roast more evenly outside the shell, making under-or over-roasting less probable. So why wouldn’t all chocolatiers shell their beans first? Ziegler thinks it’s probably just a bias toward tradition. Other experts we spoke with say money is the real issue. Roasters are extremely expensive, and since many manufacturers are equipped with traditional whole-bean roasters, they don’t often upgrade.
On the Ground
After roasting, the nibs are ground into chocolate liquor (which contains both cocoa solids and cocoa butter); that liquor is then pressed to remove cocoa butter and ground into small particles. With this information in mind, we took a closer look at the cocoas and realized that some seemed to be ground finer than others—an observation that was confirmed when we put each powder under a microscope. Here again a pattern emerged: In general, our top brands had small, distinct particles, while weaker-tasting powders had much larger particles. Though manufacturers wouldn’t disclose the aim of their grind size to us, our finding made sense: The smaller the particle the more surface area that’s exposed, hence the more flavor that’s released.
Our preferred brands, including our top pick, shared these two key features: They were roasted from nibs versus whole beans, and they boasted a smaller particle size. In cookies, cake, and hot cocoa, tasters repeatedly singled out our winner's chocolate flavor and particularly deep complexity. Even better, this cocoa met our original goal: Not only is it one of the least expensive brands on the market but it’s one of the most widely available, too.
We had just one more test before we were satisfied: To see how our winner measured up to the Callebaut, we baked chocolate cakes with each brand and tasted them side by side. Just as it did in our previous tasting, the Callebaut wowed tasters, who swooned for its elegant “dark-chocolate” flavor. But our winner didn’t disappoint, earning high marks of its own. The bottom line: We’ll still stock Callebaut for special-occasion baking, but for everyday cocoa needs, our winning supermarket brand takes the cake.