Fat: An Appreciation of a Misunderstood Ingredient, with Recipes

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Butter is unique in the world of fat. Unlike other animal fats, it doesn’t require that we kill an animal to obtain it, and without us it wouldn’t exist. But just what is butter, exactly? The science behind the transformation of liquid milk into a solid fat is not completely understood. Anyone who has been distracted while whipping cream knows how quickly it can turn to butter. Whipped too long, cream changes from a stable foam into a combination of fatty globules and a watery liquid, or buttermilk. Those fatty globules are not pure fat, but an emulsion of butterfat, water, and milk solids. The fat content of butter is naturally about 82 percent–this is the European standard for butter–although it can range up to 86 percent, depending on the cow and its diet. In North America, butter’s minimum fat content is set at 80 percent, so water is often added to lower the butterfat to the legal minimum. What’s in the other 20 percent of butter? Mostly water–around 18 percent, which explains the sizzle when butter hits a hot pan–and the rest is milk solids. Those milk solids will burn in the pan if the butter gets too hot, which is why butter is not the best fat for frying.

Butter is a very complex fat, containing more than 500 fatty acids and 400 volatile compounds, all of which determine its flavor. The breed of cow, its diet, and the season all affect the taste, texture, and look of butter. Most of us have forgotten that butter, like many foods, is seasonal. In spring and early summer, butter is a deeper yellow because the cows eat grass at this time of year, which has a high percentage of orange and yellow carotenes. The pasture is also filled with herbs and flowers, which gives the butter floral and herbal notes. In winter, the cow’s diet is supplemented with silage, so the butter is pale, higher in fat, firmer, and milder in taste. There is a direct link between what the cow eats and the flavor of its butter, but most of us have never tasted herbs or flowers in our butter.

Before the advent of refrigeration, butter shipped to towns and cities was highly salted to preserve it, but it still often went rancid and was sometimes adulterated. Only those who lived in the countryside and churned their own enjoyed the taste of fresh butter. Thankfully, our butter is no longer adulterated, since it is highly regulated and mass-produced, but the same system that guarantees a certain standard also results in a uniformity in both the butter’s color and (lack of) flavor. Our butter is often frozen for long periods of time and may be months old before reaching the store. Butter’s delicate flavor is so easily overwhelmed that most of us don’t know what good, fresh butter from grass-fed cows tastes like.

Good butter is smooth, unctuous, and creamy under the knife and bursts with myriad flavors in the mouth. These flavors, which range from clean, delicate, and sweet to tangy, ripe, and complex, are determined by the taste of the cream and how it is handled and churned. Butter made with fresh cream is milder in flavor, so it is often called “sweet.” It is not sweet like sugar, but it has none of the tang and depth of cultured butter. Cultured butter is made from ripened cream, or cream that has lactic cultures added before churning, giving the butter a more complex taste that is nutty and mildly acidic. These flavors occurred naturally in butter in the past, before pasteurization, but now they must be added back. The longer the cream is ripened, the more developed the butter’s flavor will be. Both sweet and cultured butter can be salted to add taste and to help preserve it. Salt is sometimes also used to mask off tastes. The amount of salt added varies from almost nothing to 3 percent. Salted butter can have a lower fat content than unsalted, and for that reason unsalted butter is often specified in recipes. Higher-fat butters, with their lower water content, are firmer and better for cooking and baking. Using unsalted butter also allows the cook to control the amount of salt added to a recipe. Salted butter is often regarded as inferior, but this is not always true. A small amount of salt, used in what the French call demi-sel, or lightly salted, butter, can enhance the flavor of both the butter and whatever is mixed with it. If you doubt it, try lightly salted butter on toast with jam; the way the salt in the butter intensifies the fruit’s sweetness is a revelation. There is a long tradition of salted butter in Brittany, the only region of France that uses salted butter exclusively, even for baking and desserts. Salted butter is currently enjoying a renaissance elsewhere, too. It’s not just fine sea salt that can be added to butter; large, irregular salt crystals can be folded into the butter at the end of the churning, giving the butter an almost gritty texture. When this butter melts in your mouth or on your fish or potatoes, those salt crystals burst on your tongue, highlighting the butter’s taste.

French butter has long been considered the butter benchmark, and several French butters have achieved AOC (Appellation d’Origine Contrôlée) status, like many French wines and cheeses. These butters express what the French call terroir, or a unique essence of place, and you can tell them apart by their taste. These AOC butters, which come from the regions of Charentes-Poitou and Normandy, are made using the cream from pasture-fed cows that is ripened for a minimum of twelve hours. The cream is churned slowly in small batches and is often finished by hand, giving the butter a superior flavor and texture. Many gourmets regard Echiré butter, which is still made in wooden churns, as the best butter in the world. The French, however, don’t have a monopoly on good butter, and many small producers in other European countries and the United States are producing high-quality, distinctive, and tasty butter.

Rich, fatty, and full of calories and cholesterol, butter hasn’t received any good press in a long time. Butter is a mainly saturated fat (see below), and unless it is clarified (see page 23), it is less useful for cooking than other mainly saturated fats because of its milk solids. Although those milk solids limit the usefulness of butter for cooking, they are the reason butter is such a flavorful fat. Many of butter’s saturated fatty acids are short- and medium-chain ones, which means our body uses them up quickly rather than storing them on our hips. Many of butter’s fatty acids are also very good for us: lauric and butyric acids boost our immune system, while stearic and palmitic acids lower our LDL cholesterol. Butter contains the fat-soluble vitamins A, D, E, and K, plus copper, zinc, chromium, selenium, iodine, and lecithin, so butter is actually good for us.

Note: These figures are approximate and vary with the breed and diet of the cow. The numbers don’t total 100, since butter also contains water and milk solids.

To enjoy the benefits of butter you must eat the best you can buy. Good butter not only tastes better, but it is better for you. Butter from pasture-fed cows has omega-3 fatty acids, which we need more of in our diet. Butter has the natural trans fat conjugated linoleic acid (CLA), which behaves like omega-3 fatty acid in our body and is reputed to protect against heart disease, cancer, and weight gain. Butter shouldn’t taste only of fat, but also of what the cows ate. We should be able to savor the grass, the herbs, and the flowers. While we are all willing to spend a small fortune on deluxe olive oils, we grab a pound of butter without thinking.

Next time you eat butter, really taste it. Cut a thick slice, smell it, and place it on your tongue. Let it melt in your mouth and savor its taste. Remember how special butter is in the world of fat.

Keeping and Using Butter

Whether salted or not, butter is perishable, and it begins to slowly deteriorate from the moment it is made. Although it is mainly saturated fat, which tends to turn rancid more slowly, those milk solids in butter speed up the process.

Freshly churned butter once had a cachet, and many food lovers went to extreme lengths to make sure they could enjoy it daily. In Normandy, butter was churned very early every morning, then rushed to the breakfast tables of discriminating and no doubt late-rising Parisians. Today, you probably won’t be able to taste truly fresh butter unless you know someone who makes his or her own butter or you churn it yourself (see page 21).

Homemade or not, your butter should be refrigerated and well wrapped to protect it from light and any strong odors. Butter will absorb any odors that are circulating in your refrigerator. If your refrigerator is full of truffles from Périgord, you’ll end up with truffle-flavored butter, which would be great, unless you were planning to bake shortbread. As for using the butter compartment in your refrigerator: don’t. By keeping the butter at a warmer temperature than the rest of the refrigerator and exposing it to oxygen, it just speeds up the butter’s decline. Butter can, however, be frozen.

A History of Butter

Humans have been eating butter for a very long time. The domestication of goats, sheep, and cows began in Mesopotamia and Romania sometime between 9000 and 8000 b.c. Although these animals were initially raised for their meat, those keeping them no doubt quickly learned how to use their milk. The leap from herding animals for meat to milking them is a big one, however, and no one is sure exactly when it happened.

Sumerian temple friezes from 2500 b.c. depict scenes of butter churning, so it has generally been accepted that butter is at least 4,500 years old. However, science has recently proved that butter is even older than that. Traces of butterfat found on pottery fragments have been dated to 4000 b.c., proving humans have been making butter for at least 6,000 years. There is no way to know how butter was first discovered, and its genesis is part of food folklore. A popular legend relates how a traveler carrying milk arrived at his journey’s end not with the thick, creamy milk he’d started with, but a thin, watery liquid full of lumps of fat. His bumpy journey had churned his milk into butter. While butter’s discovery was probably just such a lucky accident, it was also a momentous one. That a liquid could be transformed into a solid bestowed on butter a very special status. From its very beginnings butter was never simply a food; it was also considered a formidable medicine and a useful cosmetic. Many thought it had magical powers and was a worthy sacrifice to the gods.

Although butter keeps longer than milk does, it is still highly perishable, especially in warmer climates. Ever resourceful, humans discovered they could prolong butter’s life by cooking or salting it. In India and the Middle East, butter was heated and the milk solids removed, preventing it from turning rancid. In India, ghee is as important for its role in religious ceremonies as it is as a food. Around the Mediterranean, where other fats and oil were available for cooking, butter was often reserved for external use. In fact, in many cultures the idea of eating butter was ridiculous; it was considered something only a barbarian would do. In his Natural History, Pliny discusses butter’s medicinal properties and refers to it as “the most delicate food among barbarous nations” (though he points out that it is not something a Roman would eat). The majority of people who ate their butter in its solid state lived in the cooler climes of northern Europe and the grasslands of Central Asia, where butter lasted better and the abundant pastures provided food for the animals. The Vikings and Celts who spread butter culture throughout northern Europe also valued butter’s medicinal qualities, and their word for “butter” and “ointment” was the same. Even though butter kept longer in northern Europe, it still went rancid, and there was a continual search for ways to prolong its freshness. By 1000 b.c. the Celts were mining salt in Central Europe and realized that adding salt helped their butter keep, while those living in Ireland, Scotland, and Scandinavia preserved their butter by burying it in peat bogs (see page 35).