Everything you want to know about chocolate
For as long as I can remember, chocolate has been one of my chief extracurricular activities. From brownies to birthday cake to mousse, I've formed an emotional bond with the stuff. I love it all: from a mild and milky Hershey's Kiss to the fruity astringency of a dark chocolate bar. Who wouldn't become hooked on something that adds such depth of flavor, rich texture, and inexplicable allure?
Inseparable from its history, chocolate retains the folklore and romance surrounded by the ancient cultures of the Mayans and Aztecs and the kings, queens, and pirates of the Spanish court. Originally consumed by the Aztecs as a frothy, bitter drink, chocolate was believed to have divine properties and was considered so valuable that it was used as currency. Even the Latin name for the cacao tree, Theobroma cacao, means "food of the gods."
As chocolate traveled with the Spanish explorers, sugar cane and honey were added to suit European tastes, and it quickly became an elite and fashionable drink throughout Spain. It was not until the rise of industrialization, and the help of chocolate giants like Rodolphe Lindt, Henri Nestle, and Milton Hershey, that chocolate became widely available. From "food of the gods" to "gimme a break," chocolate spans centuries of cultures and tastes and still remains a coveted treat and ingredient. Despite its long history, many transformations and seemingly limitless varieties, you don't have to be Aztec god, nor Oompa Loompa, to understand and appreciate chocolate.
For bakers, chocolate is one hell of a complicated ingredient—over 600 volatile compounds contribute to its aroma and flavor. So if you want to bake with chocolate, it helps to know some fundamentals. Chocolate's taste and texture are products of the variety of cacao tree, where it's grown, and how it's fermented, dried, roasted, and tempered. Here's what you need to know.
Cocoa vs. Cacao
What's the difference? Cacao refers to the tree, pods, and seeds from which chocolate is derived. Cacao trees (or if you're feeling like a botanist, Theobroma cacao, derived from the Greek for 'food of the gods') grow near the equator. Major growing regions include Africa, South and Central America, and the islands of Indonesia and Malaysia.
Cacao doesn't become cocoa until the pod is opened and fermented. That's when you get all the forms of cocoa: butter, powder, and liquor.
What's in That Chocolate Bar?
Whether you buy a small-batch chocolate bar or an industrially manufactured product, all chocolate is composed of some of the same basic ingredients. It's the combination of these ingredients that gives chocolate particular qualities. Is it rich and creamy? Does it melt readily? Is it sweet or is it bitter?
While the ratio of ingredients determines a lot about the final product, it's not the complete picture. If you think about chocolate as a recipe, the technique to make the chocolate is equally as important as the ingredients. Imagine if you had really high quality ingredients to make chocolate chip cookies, but didn't know how to put them all together—the quality of ingredients do not always guarantee a delicious final product. Just like a baker, it's job of the chocolate maker to skillfully bring the ingredients together.
Chocolate liquor: Chocolate liquor (which has nothing to do with chocotinis) refers to the paste made from ground cacao beans, and it's what gives chocolate its core flavor. Chocolate liquor is composed of cocoa solids suspended in cocoa fat, and is naturally about 55% cocoa butter. The "liquor" part of the name refers to the warm chocolate's liquid state. When chocolate liquor hardens, it's commonly known as "unsweetened chocolate."
Cocoa solids: The "solids" in chocolate liquor are the particles of fiber, protein and starch, which are suspended in the fat (cocoa butter). If you think of chocolate liquor as a nut butter, the cocoa solids are what give impart flavor characteristics, while the fat makes it smooth and flowing.
Cocoa butter: Yes, this is the same cocoa butter that's in your body lotion. In fact, its high demand in both the food and cosmetic industries make it chocolate's most expensive ingredient. Cocoa butter is the naturally occurring fat in cacao beans. Although it doesn't significantly contribute to flavor (it's pretty bland), it impacts the chocolate's texture, shape, and melting qualities. The structure of the fat molecules gives chocolate its glossy appearance, a hard but not greasy surface, the snapping sound when it breaks, and its smooth, creamy texture. While chocolate liquor naturally contain cocoa butter, additional cocoa butter is often added during chocolate manufacturing (the additional cocoa butter is included in chocolate percentage).
Sugar: Without sugar, chocolate would be about as fun as eating coffee grounds. Cacao is naturally bitter and acidic, which may have been fine for the ancient Aztecs who ate and drank it unsweetened, but not for your s'mores. Sugar is the second most prevalent ingredient in dark chocolate and plays an even bigger role in many milk and white chocolates. Crystalline sucrose, your basic table sugar, is most commonly used in chocolate production, where it's pulverized to less than 25 millionths of a meter to feel smooth and creamy on your tongue.
Milk solids: Milk solids are the defining ingredient in milk and white chocolate (although dark chocolate in America can contain up to 12% milk solids). Also called "milk powder," milk solids are a manufactured dried milk product that doesn't add any unwanted moisture to the chocolate. Milk chocolate must contain at least 12% milk solids, which contributes to its characteristically sweet and mellow flavor. Milk chocolate often has a softer, less snappy texture than dark chocolate because the amount of milk solids and sugar outweigh the amount of chocolate liquor and cocoa butter.
Flavorings: Vanilla flavor and salt are two of the most common flavor additives in chocolate. Vanilla adds slight floral notes to chocolate's flavor, which complement its natural bitterness. Other flavorings includes spices, nuts and any other flavors.
Lecithin: Almost all chocolate contains small amounts of lecithin, an emulsifier extracted from soybeans. If there's no water it chocolate, why does it need emulsifiers at all? Despite usual typecasting, lecithin does not play the roll of an emulsifier in chocolate. Instead, it reduces chocolate's viscosity, which improves the flow of melted chocolate. This comes in handy when enrobing truffles, glazing, and spreading chocolate out to create chocolate décor. It also allows the melted chocolate in your mouth to more quickly gush over your taste buds for a full-flavor experience.
Cacao By any Other Name
Just like coffee, which comes in species like Arabica and Robusta, chocolate has its own cast of beans. Most fall into three categories: forastero, criollo, and trintario.
Forastero beans make up about 70% of the world chocolate crop and are sometimes referred to as "bulk beans." Originating from the Amazon, today forastero trees grow all over the world—the majority being grown in West Africa. It's a hearty variety that produces better yields than its fancy-pants cousin criollo. Yet it also requires a longer fermentation time to remove its high astringency.
Criollo, meaning "native" in Spanish, was the predominate type of cacao when the Spanish invaded the Americas. Today, due to its mild bitterness and acidity, it's often considered the world's top of the line chocolate. But complex fruitiness and low bitterness and astringency come at a price; the pods have a low yield, are prone to disease, and can be expensive to grow. Criollo beans account for a mere 10% of the world's chocolate supply. Manufactures do not typically advertise the type of beans they use, but a clue that your chocolate might be made with criollo is the chocolate's light reddish hue. But there are good criollo chocolates and bad criollo chocolates—don't just a bar's heritage over your own tastes.
Trinitario A hybrid of criollo and forastero beans, trinitario is a heartier variety with lower bitterness than forastero. The flavor is less fruity than criollo with more earthy notes.
Take note: you can make generalizations about each bean, but using a particular bean doesn't guarantee quality chocolate. Think of cacao varieties like wine grapes. They have broad differences, but the final product is as dependent on the manufacturing process as the source ingredients. So don't assume that a bar made with criollo beans is automatically delicious.
Chocolate tastes different depending on where it's grown; like wine, cacao beans differ widely by terroir: the effects of place, from the soil to the water and climate, that influence flavor. For example, South American beans tend to be intensely fruity and floral, African beans are known for simple and earthy chocolate flavor, and Madagascar beans are often fruity and acidic. What's the best way to learn about terroir? Taste all the chocolate you can.
What Chocolate Percentage Means (and What it Doesn't)
The percentage on a chocolate bar tells you how much in the bar come from the cacao bean. We're talking about the chocolate liquor and cocoa butter. Although the percentage reveals some information about how much cacao you're getting, it doesn't tell you anything about the ratio of chocolate liquor to cocoa butter. Therefore, one chocolate labeled with 75% could contain all chocolate liquor with no added cocoa butter, while another 75% bar could contain only 60% chocolate liquor and 15% cocoa butter.
These two chocolates would be drastically different—although both would contain about the same percentage of sugar/sweetness, the chocolate bar containing no added cocoa butter would be much darker than the chocolate bar containing 15% cocoa butter even though the two are both labeled 75%. The darker bar is not necessarily better than the other. It simply offers a different intensity and texture.
What does this all mean when it comes to choosing a chocolate bar? It means that a higher percentage does not always guarantee a darker chocolate (a 60% chocolate could theoretically contain more chocolate liquor than a 70% bar), but it does guarantee a less sugary one. There's a growing trend of small, adventurous chocolate manufacturers (and even some of the bigger ones) making milk-dark chocolates, which contain high percentages of cacao (around 50%), along with milk solids, resulting in less sweet versions of a typical milk chocolate bar.
What's the Deal With Tempering Chocolate?
Cocoa butter's molecular composition is where tempering comes into play. Chocolate fats can form into one of six types of fat crystal structures, but since each structure has a different melting point, only one structure (called Beta V) is beneficial for snappy, smooth-melting chocolate.
When tempered, chocolate is carefully cooled to specific temperatures and agitated to create "good" stable Beta V fat crystals. These good crystals melt just below body temperature, which means the chocolate releases its flavor as soon as it warms up in your mouth. The fat crystals, which surround the cacao solids, melt as they hit your tongue, releasing the flavorful solids within on your taste buds.
What Chocolate Does for Your Desserts
Obviously we bake with chocolate because it tastes so good. Brownies and chocolate chip cookies just wouldn't be themselves without it. But chocolate does a lot more for baked goods than flavor them.
It provides structure. Baked goods are a careful balance of rough, load bearing structural ingredients (think of flour and egg white like concrete and steel beams) and tenderizers (such as sugar, fat, and egg yolks) that keep cake softer than bread. Chocolate has a lot of fat, but it winds up adding more structure than tenderness to baked goods. Cakes or cookies with cocoa powder need less flour than those without, and a sweet made with dark chocolate will be tougher than one made with milk.
It adds texture: What makes mousse, frosting, glaze, and ganache so addictive? Fat! And the more fat you add, the smoother and creamier those sweets will be. High-fat chocolate enhances those creamy textures in dairy-based chocolate sweets like mousse.
It absorbs moisture. Flour soaks up the water in eggs, butter, and milk, which you need for a solid baked good. Cocoa powder does the same, and pound for pound it can absorb more liquid than flour. So if you're adding cocoa to a cookie or cake you can decrease the flour.
How Good Chocolate Goes Bad
If you've ever found a surprise stash of last year's Halloween candy in the cupboard, only to be disappointed when you unwrap a gray, streaked lump of what used to be a Snickers, you've seen chocolate bloom. Bloom is a chocolate defect typically caused by improper storage or handling. There are two types of bloom: fat bloom and moisture bloom. You can fix the former; the latter is irreversible.
Fat Bloom: With fat bloom, the gray streaks you see are visible fat crystals that have separated and settled on the chocolate's surface. Either the chocolate that wasn't properly tempered to begin with, or it got too hot in storage (or during handling), then melted and recrystallized in an un-tempered form. You can fix fat bloom by re-tempering your chocolate. Here's how.
Moisture/Sugar Bloom: Moisture bloom, on the other hand, is irreversible. And just like it sounds, it's caused by exposure to moisture. The gray you see on the chocolate's surface in this scenario is crystallized sugar. When chocolate's exposed to moisture either by high humidity or direct contact (like wet hands), sugars in the chocolate absorb the moisture and start to crystallize. It's best to avoid melting moisture-bloomed chocolate for baking applications; the texture will be noticeably, irreversibly grainy. Save moisture bloomed chocolate for high liquid, high heat applications such as hot chocolate or chocolate sauce, where the sugar crystals are able dissolve.
How do you know which bloom you're dealing with? Rub a small piece of the bloomed chocolate on your lip. If it feels gritty or rough, you're feeling the sugar crystals and it's moisture bloom. If it still feels smooth, it's fat bloom.
If you want to avoid blooming in the first place, here are some tips:
- Store chocolate between 55° and 65°F in a low moisture environment.
- Don't store chocolate in the refrigerator unless it's wrapped tightly in several layers of plastic wrap. If it's not wrapped very tightly, water droplets will condense on the chocolate's surface. I cringe at the thought of a helpless, unprotected hunk of chocolate in that damp, high-moisture environment.
- When handling chocolate, wear gloves, or at least dry your hands very well. This way, any moisture on your hands doesn't transfer to the chocolate. Gloves also protect the chocolate from the heat of your hands.
Know Your Chocolates
Here are the major varieties of baking chocolate you'll find in the wild.
Bittersweet, Dark, and Semi-Sweet
It's hard to disentangle these categories because "bittersweet" and "dark" are often used interchangeably. Typically, "semisweet" contains 35 to 45% cacao and is sweeter than dark/bittersweet chocolate. But there are no legal regulations to distinguish between dark, bittersweet and semi-sweet. They all simply must contain at least 35% unsweetened chocolate and can only contain up to 12% milk solids.
Milk chocolate must contain at least 10% cacao and 12% milk solids. Its flavor, texture, and quality can vary significantly due to the many different flavors of dairy solids available. Some milk chocolate has a ripe, even sour, flavor, while others are mellower. Some milk chocolate even has caramelized notes from when the milk and sugar are heated together.
Since white chocolate has cocoa butter but no chocolate liquor, some argue that it's not really chocolate at all. But whatever you call it, the term "white chocolate" does have a regulated meaning. It must contain at least 20% cocoa butter and 14% milk solids.
Unsweetened ("100%") Chocolate
When chocolate liquor is sold in its solid form, it's called "unsweetened chocolate." The bar is 100% chocolate mass and has no sugar.
Couverture comes from the French word "to cover." Also called dipping or coating chocolate, couverture contains extra cocoa butter (about 31-38% fat), which gives it a glossy finish and allows it to flow easily. For this reason, it's typically used for coating or glazing cakes and pastries.
What peanuts are to peanut butter, cocoa nibs are to chocolate. They're little nubs or cacao bean that have been roasted and hulled but not ground. They're crunchy with a dark roasted flavor and bitter bite, and bring great texture and flavor contrast to baked goods.
Cocoa powder is made when the cacao liquor is pressed to remove the cocoa butter, resulting in a fine, unsweetened powder. Cocoa powder comes in two different forms: natural and Dutched. Natural cocoa powder retains the cacao's natural acidity, while Dutched is neutralized with an alkali chemical. As a result, Dutched cocoa is less acidic and has a darker color and more mellow flavor.