Butter

The science of butter starts with the primary ingredient — milk The science of butter starts with the primary ingredient — milk. Milk is 88 percent water, 3.5 percent fat, 3.25 percent protein, and 4.6 percent lactose (sugar). Milk is homogenized to prevent the fat from rising to the top of the milk. This is achieved by "forcing fat globules into smaller and smaller particles so they can't find each other again.

Cream to butter Heavy cream is an emulsion. An emulsion exists when tiny droplets of one type of liquid are floating around in another type of liquid that does not like to mix with the first.

In the case of heavy cream, tiny globules of fat are suspended in mostly water. The globules are surrounded by membranes of phospholipids (fatty acid emulsifiers) and proteins, which prevent the globules from pooling together in a single mass. Shaking the cream forces the fat globules to slam into one another. If they hit each other with enough force,the membrane around fat globules breaks and they will stick together, the fat collection becoming bigger and bigger with each extra globule. After enough shaking, the fat globules form a chunk of butter.

What remains is a watery liquid with small butter grains floating in it. This is called “buttermilk” and is drained off and saved for other purposes. The butter is pressed and it into a solid mass to remove any remaining pockets of buttermilk or water.

Activity Determination of Milk Fat (lipids) from Cream 1. Transfer 150 mL of the heavy cream into a plastic 500 mL water bottle. (The temperature of the cream should be approximately 13°C). 2. Cap the bottle carefully and shake in a horizontal position until a distinct separation of butter particles occurs (this will take a significant amount of effort; be persistent). 3. Drain off liquid portion and discard it. What is this discarded portion called?

4. Wash the butter particles twice with cold tap water 4. Wash the butter particles twice with cold tap water. Drain off as much water as possible. 5. Transfer the butter particles to a clean beaker. 6. Press and work the butter particles into a mass. Drain the released liquid (make observations of the liquid). 7. Dry the butter in paper towel and weigh the dried butter to calculate percent milk fat.

Percent Milk Fat Calculate the % of fat (Mass of fat/mass of cream)*100

Butter a. Does the size of the bottle neck matter? b. Does how long you shake the bottle matter? c. Does the temperature of the cream matter? d. Does the brand of the cream matter?

Butter e. Does it matter if you use cream from cow’s milk or goat’s f. Can you make butter out of powdered milk? g. Can you make butter out of almond milk? h. Does it matter if you wash the butter? i. Does it matter if you knead the butter? j. Does it matter if you put the butter on paper towels?