The Kitchn's Baking School Day 6: All about butter.
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It would be near impossible to talk about all these pastries and baked goods without discussing one big key ingredient: butter! Want tender biscuits and a flaky pie crust? Butter is the answer. Looking for moist, delicate cakes? You'll need butter. Creamy frostings? Yup, you guessed it — butter is the key.
When it comes to baked goods, butter is what makes things tender, flaky, flavorful, decadent, and creamy — all things that a good pastry should be. Butter really does make everything better.
The Different Types of Butter
Since butter is responsible for so many things — including not only tenderness and flakiness, but also taste, leavening, and structure — it is important to know the difference between all those butters at the grocery story before picking up a few sticks and heading off to make a batch of cookies.
At the store, you will typically find sweet cream butter and unsalted butter. Both butters are made in the same way with the same cream, but sweet cream butter usually has salt added. Contrary to the name, sweet cream butter has not been sweetened. In general, sweet cream butter is better for spreading on toast, while unsalted butter is better for baking. This is so we can control the exact amount of salt we are adding to our recipes.
You may also see cultured butter at the store. The main difference here is that this butter is made from cream that has been cultured and allowed to slightly sour. It is the type of butter most traditionally found and used in Europe. "European-style" butter sold in North America, like Plugra, is cultured or sweet cream butter with cultured cream flavor added in.
Why We Use Unsalted Butter, but Still Add Salt
If you are going to be doing a lot of baking, it is best to keep unsalted butter on hand. But then way do so many recipes call for additional salt? The main reason: control.
Since different butter manufactures add different amounts of salt to butter, using unsalted butter takes the guessing out of the equation. You get to control the overall salt content. Most recipes take this into consideration when being developed and call for unsalted butter in the ingredients, and this advice is worth heeding.
In addition, the salt in salted butter can end up making delicate, sweet pastries taste overly salty. Think about a buttercream, where butter is a major component and is responsible for much of the flavor — salty buttercream would probably taste very unpleasant piled high on a cupcake.
Butterfat and Moisture Content in Butter
Butter is made by churning cream until it separates into liquids (buttermilk) and solids (butterfat). In North America, commercially sold butter must contain at least 80 percent butterfat, while European butters typically contain at least 82 percent and up to about 85 percent. The remaining contents of the butter's makeup includes water and milk solids. The lower the butterfat content, the more liquid (and less fat) is being added to your recipe; the higher the butterfat content, the more fat (and less liquid).
So what does this all mean when it comes to baking? Since having less butterfat essentially means more liquid, then consider what adding a bit more liquid will do to your doughs and batters. This small increase might not be as noticeable in simple brownies or quick-breads, but the additional liquid can weigh down doughs and leave pastries a bit tougher. Butter with more butterfat will also remain solid slightly longer in the oven. Want crisper, flakier croissants and puff pastry? Go for the butter with the higher butterfat content.
Also, it is worth noting the different between the moisture and moistness butter adds to a recipes. Moisture refers to the liquid content while moistness refers to the fat. Nearly all recipes call for both, but for different reasons. In general, fat (including that in butter) tenderizes baked goods. Liquids (again, including that in butter) help hydrate proteins (found in flours and starches), bind ingredients together, and also aid in moistening.
When to Splurge on Good Butter
With its more-developed flavor and higher fat content, why don't we use European butter for everything? The biggest reason for those of us in the United States is that it's typically much more expensive than sweet cream butter — using all European butter in something that uses half a pound of butter, like pie crust, can really add up.
For everyday cookies and brownies, regular sweet cream will suffice. The butter here is a player, for sure, but there are so many other flavors and textures going on that it's fine to use an everyday brand of butter. In recipes where a slight increase in water content and butter flavor would make a difference, like with flaky pie crusts and croissants, it's worth paying for the good stuff.
Butter in Recipes
Moisture and flavor might be the most obvious reasons to use butter in baked goods, but there are several other roles butter is playing as well. In things like cakes, cookies, and muffins, butter coats the proteins and starches during the mixing step and results in a more delicate crumb.
In many of these types of pastries, the butter is creamed with the sugar before being mixed with other ingredients. Through this process, the sugar granules actually cut into the softened butter and air is forced into the mixture, which ultimately helps to leaven the pastry.
Even in recipes that do not call for the creaming method, butter assists in leavening by creating steam when placed in a hot oven. Recall what makes up butter other than butterfat? The liquid portion of butter adds moisture (as opposed to the moistness added from the fat), and in baked goods like puff pastry and croissants, the liquid in the butter begins to evaporate and create steam, which lifts the pastry as it bakes.
Why Butter Temperature Matters
Temperature is a key factor in how butter behaves within a recipe and how it mixes with other ingredients in a batter or dough. Rarely does a recipe list butter without noting if it should be cold from the fridge, softened to room temperature, or even melted.
With softened butter, the fat can be easily creamed together with sugar, or used to coat flour particles. This creates a more even distribution of fat throughout the dough or batter, yielding a tender final product. Like using room-temperature eggs, room-temperature butter creates a more homogenous batter and prevents buttercream from "breaking" (more on this tomorrow).
Softened butter should still be cool, but malleable. It should be able to hold its shape and still firm enough that if you press your finger into it, the impression is clean. It should not be squishy, oily, or appear melted. Too-warm or melted butter loses its ability to cream and hold air when beaten.
In most kitchens, it will take about 30 to 60 minutes to soften butter to room temperature. Forgot to remove your butter from the fridge? Need to speed things up? Try cutting the butter into smaller pieces, carefully grate it with a box grater, pound it flat with a rolling pin, or use the indirect heat of a double-boiler (making sure it does not melt!).
Very cold butter is used in recipes where you don't want the butter to combine with the rest of the ingredients; you want it to stay cohesive. Pie dough, puff pastry, biscuits, and scones all typically call for very cold butter so it remains intact and unincorporated, which leads to distinct layers in the finished baked goods.
Why layers? As mentioned earlier, butter creates steam as it melts in a hot oven, and in pastries where cold butter is used, the steam from the melting butter expands between the layers of dough. This creates pockets of air, yielding a flaky end product. (Quick tip: Try grating frozen butter into biscuit or pie dough in order to easily distribute the butter without over-working it, and in turn, softening and warming it!)
On occasion a recipe will call for melted butter. Here, the butter provides moistness and flavor but does not contribute to structure. Since it is not being creamed and aerated nor kept in cold pieces that create steam in the oven, melted butter does not serve the same roll in leavening pastries as softened and cold butter do. However, it does still play a roll in the texture. For instance, using melted butter in a cookie recipe will make them chewy.
You may also see melted butter in recipes that only require gentle mixing (or the "muffin method" where the dry ingredients to be mixed with the all of the wet), like quick-breads, pancakes, brownies, some cakes, and muffins.
Although it can stand at room temperature for some time, it is still best to keep butter in the refrigerator if you don't have immediate plans for using it — or even in the freezer. Butter is susceptible to odors, so keep it covered and separate from foods with strong odors, like fish or onions. Exposure to air also quickens the time it will take for the butter to turn rancid. Butter will usually keep for about three months in the refrigerator and about three to four days if left at room temperature.
1 stick of butter = 1/2 cup = 8 tablespoons = 1/4 pound = 4 ounces
Every lesson has three homework options. Maybe you’ve already got one down, or you just have time for a quick study session. So pick one, and show us by tagging it with #kitchnbakingschool on Instagram or Twitter.
Brush up on why recipes call for unsalted butter.
Go to the grocery story and check out the butter aisle; really look at the fat content of the unsalted butter and then splurge on one European-style butter.
Play with two sticks of butter: using a stand or hand mixer, cream one stick while cold and watch how it behaves. Leave the other on the counter for an hour and check it every 10 minutes, then cream it at the end. Notice the difference in texture and share your thoughts in the comments. (The creamed butter can be refrigerated or frozen for a later assignment.)