Milk and coffee are obviously the best of friends: They've been combined since some of the earliest days of caffeination, for both practical and preferential reasons. (The former because of the added calories and nutrition, the latter because, well, milk and coffee taste great together.)
Anyone who's in the market for dairy these days, however, knows that the coolers at every market are stuffed with a staggering array of bottles and cartons with red, blue, and yellow tops—not to mention cartoon drawings of "happy cows" and all manner of certification labels. How's a person supposed to choose?
Here are a few tips for getting the most out of your milk—and, therefore, the most out of your daily mug.
Animal of Origin
It might seem strange to consider the type of animal that produces the milk you use in your coffee, since cow's milk is utterly (udderly?) ubiquitous in cafés, and has been, for most of us in North America, the stuff we've glugged in bottles and dunked cookies in since we were kids.
But you're free to make choices based on flavor and preference as the result of taste and research. You don't have to automatically reach for cow's milk, gosh darn it, because there's a whole world of miscellaneous mammals whose dairy you might find more complex, creamy, and delicious. Explore the dairy aisle, my milk adventurers!
Cow's milk is the old standby. Depending on myriad other factors listed below, such as milkfat percentage and cow-raising conditions, these milks can provide a sweetness and texture that's perfectly complementary without being overpowering or underwhelming. They're also cheap, accessible, and familiar—which may or may not play in their favor.
Goat's milk has an almost salty, grassy, and very tangy flavor that might appeal to extreme Greek yogurt addicts. Lacking the sweetness of cow's milk, it blends best with coffees whose roasts are designed specifically for sugar browning (read: mediumish roasts, as opposed to either very dark or very light).
Water buffalo milk is a real treat if you can find it: These huge animals produce the fattiest type of milk, and though its incredibly rich texture can overpower a cup in large doses, when used moderately it can make one heck of a perfect little morning indulgence. The flavor is sweet in a tangy-cream way, which isn't for everybody, but it's certainly worth trying once. (And maybe just once: It's expensive!)
Note: We'll deal with nondairy milk in another post.
The amount of fat in your milk changes the liquid's texture as well as its flavor.
Homogenization, first and foremost, is the process by which the fat that comes naturally and originally suspended in the milk liquid is broken down into smaller and smaller particles by a combination of heat application and filtration, which allows the fat to disperse more evenly in the watery base of the liquid. The more fat the milk contained in the first place, the richer the finished homogenized product.
Sidenote: In the United States, the vast majority of milk that's processed for retail sale is entirely skimmed of milkfat upon harvesting. Once the milk liquid has been separated and identified into vats identified for each of the following "grades," milkfat is then re-introduced into the liquid to meet specific requirements as set and regulated by the USDA. The vast majority is then homogenized and pasteurized before packing and shipping.
Whole milk, despite its name that sounds synonymous with "untouched" or "straight from the cow," actually only contains a minimum of about 3.25% milkfat in order to be labeled as such, though most companies go for 4% in order to achieve maximum deliciousness. This is the most common, and probably the most useful type of milk behind the espresso bar, because the milkfat is neither too much nor too little to achieve an ideal balance of taste and texture when mixed with coffee. Creamy without turning the drink into, well, more of a snack, whole milk is the type cafés will default to when you don't specify your preference.
Reduced-fat milks of 1% or 2% milkfat don't tend to be drastically different in either flavor or mouthfeel, but they can seem a little flimsy in the cup by comparison. Often if a café doesn't have these specific types on hand, the barista will mix whole and skim milk for a sort of approximation of low-fat, which is not really ideal: barista-made combination tends to be inconsistent, either too watery or too fatty compared with its genuine bottled counterpart. Most of the time, however, latte drinkers won't notice the difference.
Skim, of course, contains no milkfat at all—which is partially what gives it that sort of blue tint it has, as only shorter-wavelength light refracts off the casein particles which make up the majority of the liquid. (Fat globules will also refract longer-wavelength colors of light, which would make it appear whiter the more colors are scattered.) The lack of fat therefore can actually make this milk taste sweeter, believe it or not, except that the lack of viscous fat won't coat or cling to the palate as well as fattier milks. Steamed, this type of milk creates a much drier and denser head of foam, but lets the espresso's flavor shine through, for better or worse; poured into regular brewed coffee, it can make the drink look almost gray and won't provide much body, but again, can seem sweeter than other types of dairy.
Cream is a slightly different animal altogether, and there are myriad types to choose from. Light cream, half-and-half, heavy cream, heavy whipping cream—what the heck's the difference?! Milkfat percentage, mostly.
Half-and-half is the least fatty of the cream category, with 12% and a sort of sweetly buttery flavor. Compared to light cream (20%), heavy cream (38%), and heavy whipping cream (also 38% but usually with some air added), the ol' half-and-half is practically a diet drink—which is good, because users tend to pour more of it into their cups to achieve the creamy texture and sweet flavor they crave. Delicious in very small doses in a drip coffee, these are almost gag-worthy as the base of milky espresso drinks—it's kind of like making a latte with warm cream cheese. On their own, they can taste more like custard or melted iced cream than just straight milk: Again, sounds great in theory, but too much of a good thing is too much.
Does organic or conventional matter when we're talking about taste? Well, here's the thing: Taste is subjective. Does grass-fed, pasture-raised beef taste better than industrially raised stuff? There aren't enough controls in these situations to really provide me with enough hard proof either way: To convince me, you'd need to raise two cows under opposite conditions but in a shared, controlled environment—which, obviously, isn't going to happen.
In my experience, however, there are differences among farm types, sizes, and styles that do seem to contribute to discernible differences in the cup.
Conventional milk often comes from large dairies with centralized processing plants and hundreds, if not thousands, of cows on the property, usually raised within enclosed sheds, and rotated on a milking and feeding schedule that is highly organized and consistent. These cows are almost never fed fresh pasture greens, but are instead given a grain-based diet possibly supplemented with dried greens or other nutrient sources. The end result can be completely consistent year-round.
Organic milk often comes from smaller farms that are frequently unified into collectives or producer co-ops, or are single-company-owned large entities based primarily in the Midwest and West Coast here in the States. The cows are required to have some access to pasture for at least part of the year, and are often fed with fresh greens while they are in season. (Practices vary; it's worth doing a little research on the brands you're considering!) Dairies that pasture-feed might face inconsistencies in product based on diet changes with the season, but that is more often the case with smaller dairies than larger operations.
As far as preference, is concerned, however, only your taste buds can tell you that. Taste, compare, and taste again.
Like with coffee, fresh is best: Unlike with coffee, however, milk can actually make you sick if it gets too long in the tooth. Bacteria and other microorganisms are interested in milk for all the same reasons we are: It has sugar and other nutrients, and it's the world's perfect food. Oh, and it tastes great. Even creepy crawlies know that.
As milk ages, it will be broken down and "digested" by the microorganisms that feast on it before we do. Pasteurization stalls this process through a controlled application of heat that kills and prevents the development of harmful spoiling bacteria, but its effects only last so long. When the goodness of milk—proteins and lactose, mostly—get broken down enough by these mini invaders, the milk is no longer delicious or healthful no matter what you do with it. (This is why only fresh milk can be cultured; sour milk that's just sat forgotten in the fridge for a month is not remotely the same thing as deliberately soured milk which has been incubated.)
The moral of the story? Take my father's advice and always look toward the back of the row of cartons or bottles for the milk with the furthest expiration date. In some places (New York City included), milk needs be labeled with a "sell-by" and a "use-by"—the former allows for three to four days' use after the date has passed, but the latter is not something to be messed with.
What kind of milk do you like in your coffee?