Clarified Butter

A jar of radiant, clarified butter.Clarified butter is butter from which water and milk solids like protein and sugar have been removed to leave pure milk fat.  As the name implies, it has a radiant clarity.  As the proteins have been removed, it can be heated to frying temperatures without burning.

Clarifying butter is simple.  If you gently heat butter in a pot, this is what happens:

  • The milk fat becomes liquid.
  • The water content begins to evaporate, gently bubbling to the surface.
  • The light whey proteins form a foam on the surface.  Once the water content has been driven off, this foam dries and forms a crackly skin.
  • The heavier casein proteins coagulate and fall to the bottom of the pot.

If you skim the layer of whey proteins from the surface of the butter as shown below, then decant the mixture to remove the casein on the bottom of the pot, you are left with clarified butter.  Easy!

Skimming whey proteins off clarified butter

The only trick is to keep the temperature high enough to evaporate the water, but low enough to avoid browning the mixture.  The lowest setting on most residential stoves works fine.  Leave the butter for an hour or two to separate into the components described above.

Commercial butter is typically around 80% milk fat, the remainder being water and milk solids.[1]  You will no doubt remove some of the fat when you skim and decant, so the yield on clarified butter is closer to 70-75% of the original weight.  In other words, if you start with one pound of butter, you will end up with about 10-11 oz of clarified butter.

 

1. Gisslen, Wayne. Professional Cooking for Canadian Chefs, Sixth Edition. Page 810.

Rhubarb Brown Butter Tart

Brown butterPossibly my favourite application for rhubarb.  Almost any tart fruit can be used, but the sour flavour of rhubarb marries beautifully with the nutty character of the brown butter.

Every time I brown butter I ask myself why I don’t do it more often.  It’s quick, more or less foolproof, and one of the great, complex flavours of the kitchen.  Simply put butter in a heavy pot over medium high heat, then remove once the moisture has boiled off and the milk solids have browned.  If you need more guidance, you can think of browning butter like making syrup: as more and more water evaporates, the boiling point of the liquid rises.  Use a candy thermometer and pull the brown butter off the heat once it reaches 130°C.

While the filling for this tart is dead simple, blind baking tart shells is a bit finicky, so this is something I make maybe once a year.  I use this standard tart dough recipe and blind baking procedure.

Fresh rhubarb is preferred to frozen, which looses a good deal of its moisture and flavour during thawing.  If using frozen rhubarb, thaw and strain off excess moisture to avoid diluting the filling.

Rhubarb Brown Butter Tart

Master Ratio – 1:2:2:3 flour, butter, egg, sugar

Ingredients

  • 6 oz eggs (3 eggs)
  • 9 oz granulated sugar
  • 1 tsp kosher salt
  • 1 tsp vanilla extract
  • 3 oz all-purpose flour, sifted
  • 6 oz unsalted butter
  • 6 oz chopped rhubarb
  • 1 French tart shell, par-baked to 3/4 doneness (recipe and procedure here)

Procedure

  1. Whisk together the eggs, sugar, salt, and vanilla until smooth and pale.  Add the flour and beat until well mixed.
  2. Heat the butter over medium-high heat in a small stainless steel pot until brown and nutty.
  3. Slowly pour the hot brown butter into the egg mixture while whisking.
  4. Distribute rhubarb evenly around the par-baked tart shell and pour butter mixture over top.
  5. Bake at 350°F until a crust forms and the filling is set underneath, about 40 minutes.  (Don’t overbake or the brown butter will separate from the filling, giving it a greasy, grainy texture…)  Cool to room temperature before cutting.  Dust with confectioner’s sugar.

The rhubarb brown butter tart, fresh from the oven

A slice of rhubarb brown butter tart

Butter and Buttermilk

I think as children most of us were taken to historical sites like Fort Edmonton to learn how the settlers made wool and horseshoes and butter. Even so, I’ll start at the beginning.

You make butter by agitating cream.

It works like this. The fat in cream is in tiny globs, each covered with a membrane that prevents the fat globs from joining together. When you agitate cream, you break these coverings, releasing the fat globs, which all rush out to join their fatty brethren and form a solid mass of butter.

To commence butter-production, fill your container half way with heavy cream. Add a pinch of salt, secure the lid, and start shaking. You don’t have to strain yourself, just use a gentle shake that you can sustain for maybe ten minutes. After a while the cream will thicken: the contents will be noticeably less fluid, and there will be less sloshing. At this point you’ve simply made whipped cream:

The cream, thickened by agitation
Once whipped cream has formed, it’s a little more difficult to keep the cream moving in the jar. Perform a couple minutes of aggressive shaking, which will separate the butterfat and buttermilk:

The separated butterfat and buttermilk


Buttermilk: A Digression

While the resulting liquid is technically buttermilk, it does not have the tanginess that we usually associate with buttermilk. Why do we think of buttermilk as sour?

An old-timey counter-top butter churn.When my mom was growing up in northern Ontario, they kept dairy cows.  They had a butter churn. Not the tall wooden ones you see at historical villages, but a large glass jar with a crank that spun paddles within.  Once the day’s cream had turned sour, they would pour it in the jar.  Once the jar was full they would make butter.

Whoa. Hold on. “Once the day’s cream was sour?”

I know.  In the age of pasteurization “sour milk” means “spoiled milk,” ie. a putrid mess of mold and coaguluum.  But before milk is pasteurized it contains a community of friendly bacteria called lactobacillus that are able to get a strong foothold on the milk before any other microbe. In my mother’s day sour milk was exactly that: sour. It wasn’t harmful, but if incubated too long could be too strong tasting.  This is what they used to make butter.  Both the butter and the buttermilk would have had the tangy taste of culture milk.

These days commercial buttermilk is made from pasteurized whole or partly-skimmed milk that has been inoculated with lactobacillus and incubated.

 

Back to the Butter…

The butterfat that has clumped together must now be worked to remove small pockets of buttermilk that remain within. When making such a small amount of butter, you can just use your hands. Knead the butter. You should see droplets of buttermilk come out.

At this point the butter is usually pressed into a mold to form the familiar bricks. Or in my case, hockey pucks:

The finished butter in a round ramekin

My finished butter was made with store-bought cream, so it has little to distinguish itself from store-bought butter, besides a slightly richer dairy flavour. It’s very good, but the benefits aren’t great enough to convince me to start churning cream for my daily supply of butter. (Maybe once I have my own cow…) It’s still a good experiment to try once, if only for general knowledge and appreciation of this rich but humble staple.