Room Temp Butter?
Exactly what is room temperature butter, or "le beurre" as the French would say? Recipes do not state an exact butter temperature and most information differs on how long it should sit out of the refrigerator before coming to room temperature. Temperatures also vary from house to house. Since butter temperature can dramatically affect the texture of baked goods, vague terms like chilled, softened (room temperature) or melted and cooled can leave you confused. Below are some guidelines to help you better understand these terms in your recipes.
CHILLED is approximately 35 degrees F. Butter at this temperature is perfect for pie crusts, croissants and puff pastry. When you incorporate cold butter into the dough it melts during baking leaving small pockets that create flaky layers. To achieve proper chilled temperature, cut butter into small pieces and freeze approximately 10-15 minutes.
As you can see in the pictures below, my butter was 45 degrees F when removed from refrigerator. It was also unyielding when pressed with a finger and cold to the touch.
SOFTENED (Room Temperature) is approximately 65-67 degrees F. This butter is perfect for cakes and cookies. When you combine the butter and sugar during the creaming process the sugar crystals penetrate and aerate the butter. These air pockets expand further with the addition of baking powder or soda, giving rise to and ensuring tender, fluffy cookies and cakes. With butter that’s too cool or warm, sugar will just mix into the butter, not cream it.
To softened butter to proper temperature, remove it from refrigerated and allow it to sit at room temperature for 30 minutes or longer. It is best to check for accurate butter temperature with an instant read thermometer. (Note: You will only need to check temperature with thermometer once. After that, you should have idea of how long it takes to soften butter in your kitchen.)
Softened butter should easily bend without breaking and give slightly when pressed. It shouldn't lose its shape and should be cool to the touch. (Note: All other recipe ingredients should also be room temperature if you do not want your butter to seize, thus undoing the purpose of waiting for room temperature butter in the first place.)
MELTED & COOLED is approximately 85-90 degrees F. This butter is perfect for quick breads, muffins and bars. These kinds of baked goods rely on baking powder or soda for their leavening instead of creamed butter. To melt, cube the butter and place in a microwave-safe bowl. Melt in 15-second increments in the microwave. You can also do this over low heat on the stove. Allow to cool about 5 minutes. The butter should be fluid and slightly warm to the touch.
At this point you may be asking if butter is made from cream, a dairy product, why can it be left out? Pasteurization is the answer. Pasteurization lowers bacteria counts in the cream to safe levels, and then once the butter is made, its physical properties protect it from bacterial growth. Bacteria needs water to grow. Butter consists mostly of fat (at least 80%) and water. The water content is fairly high, but due to the churning process, water molecules are separated and surrounded by fat, which is almost impenetrable to bacteria.
There is some debate as to how long butter can be left out. 1-2 days, up to 10 days? Butter, like all food products, will spoil eventually so it is better to store long term in the refrigerator to maintain its freshness. If butter is unpasteurized or homemade it is considered a TCS Food and must be kept refrigerated.