Introduction
You should recall from our discussion of mixtures and substances in the fire project that milk is a colloid. When you drink whole milk, you are consuming a heterogeneous mixture of water, proteins, fats and other substances. A colloid is a mixture that like a solution never settles. One test for a colloid is that its particles will scatter light - the Tyndall effect. Some portions of whole milk will settle however. Cream will rise to the top, however, the cream is a colloid and must be separated mechanically; i.e. churning. Homogenized milk is milk that has been passed through a uniforn sieve that forms the fat globules into even sized particles that are more easily dispered.
Consuming raw milk is not advised due to the possibility
of contamination. Pasteurization
is a process that destroys most harmful bacteria. To pasteurize milk, bring
it to a steady state 145o F for 30 minutes. To convert Fahrenheit
use the following: oC
(9/5) + 32 = oF
To convert Fahrenheit to Celsius use the following: (oF
- 32) 5/9 = oC
Making Butter
First
we need to pasteurize the products. In container #1 we will place a gallon
raw milk, which the cow gave us yesterday. In container #2 we will place
a gallon of cream which was collected (and refrigerated over the past several
days). Using a hot plate, we will bring the contents of both containers
to 150-155o F for 40 minutes. Can you determine what the temperature
Celsius should be?
Collecting cream
After pasteurization, we will
let the milk and cream sit in the refrigerator overnight. By day
two, the cream should rise to the top in container #1. We will remove this
cream using a turkey baster. The remaining milk is "skim milk". Add this
cream to the cream in container #2.
Souring the cream
Now we need to sour the cream. Pour the
pasteurized cream into our 3 gallon churn and let it sit at room temperature
overnight. If it's not soured we have to let it sit longer.
Churn the Cream
Individual
|
For you this means putting several tablespoons of cream in a small jar (baby food jar). You need to bring a small jar. Shake your jar gently until the cream turns to butter and a "buttermilk" liquid residue. Spread on a piece of bread and enjoy. If it spreads, you pass! |
Class
 |
We need several students who need the extra project credit to do some churning. Churn the butter gently and continuously in approximately one-second cycles. Gradually turn the plunger as you do. The temperature of the cream has a lot to do wiht how long you will have to churn - hopefully it will be about 30 minutes. If the cream is too warm we'll get "fluffy" butter. If it is too cold the butter will fleck and not stick together. When you feel the resistance in the churn change, check it out. |
Separate the Butter
Gently scoop out the butter with a slotted spoon
and put the butter in a bowl. Pour the remaining "buttermilk" in a jar
for my wife to make cornbread with (or for me to make buttermilk biscuits
one day next week. We'll serve them with fresh butter you think?)
Finish the Butter
Using a wooden butter ladle, work
the butter back and forth on the sides of the bowl to remove the remaining
buttermilk. Pour it off - I'll drink it! Pour a small amount of cold water
in the bowl and continue to work the butter, pouring off the liquid. When
the cold water remains clear we are finished.
Salt and Mold
Sprinkle about 1 teaspoon of salt
per pound of butter. The Foxfire book says about 1/4 to 1/2 teaspoon
per pint. Work the butter into the butter with your ladle.
Spoon into molds, pressing to be sure and get all the air bubbles and water out of the butter. Remove from molds and wrap in plastic wrap until the biscuits are done!!
Criteria
Quiz
Project
BONUS OPPORTUNITY: One bonus project credit for the tribe that successfully churns the groups butter. Lowest current grade gets first choice.
If you made the individual butter, you passed.