Milk is composed of butterfat (which contains vitamin A), protein (which contains vitamin D), lactose (milk sugar), and minerals (calcium, phosphorus.) Raw milk, straight from the cow, is highly perishable and sensitive to sunlight and temperature swings. Conservation of milk is through various means:

• Pasteurization – milk is heated to specific temperatures for a specific period of time depending on the type of pasteurization taking place.
  • Pasteurization – 145 degrees for 30 minutes
  • HTST (“high temperature-short time”) – 161 degrees for 15 seconds
  • UHT (“ultra-high temperature”) – 280 degrees for 2 seconds (shelf stable milk)
• Sterilization – milk is conditioned and heated to 240 degrees F for 20 minutes and then chilled or heated to 300 degrees F for 2 seconds and then chilled. Sterilized milk is usually used for canned milks.
• Ebullition – raw milk is boiled for 10 minutes to kill bacteria and then cooled.
• Concentration – milk is processed to eliminate a large percentage of the water. If the condensed milk is unsweetened, it has to be sterilized before the concentration process.
• Desiccation – close to 100% of the water is removed.

The benefits of milk in baked products are increased crust color, increased keeping qualities due to the added moisture and fat of milk, improved flavor, increased nutritional value due to the vitamins and minerals in milk.

Forms of Milk

• Liquid whole milk is required to have a minimum of 3.5% butterfat and a minimum of 8.5% milk solids (protein, lactose, and minerals.)
• Liquid low fat milk is required to have a minimum of 2% butterfat and a minimum of 1% milk solids.
• Liquid skim milk has had most or all of the fat removed.
• Evaporated milk (whole or skim) has had 60% of the water removed.
• Condensed milk has had 60% of the water removed and sugar added.
• Dried milk can be made from whole milk, skim milk or buttermilk.

Fermented Milk

“Fermented milk” is a rather unattractive name for a yummy group of foods that is that is especially helpful for baking at altitude. The additional acid in this group helps baked goods set faster in the oven because they lower the temperature of that the eggs coagulate at. Types of “fermented milk” are:

• Buttermilk – Originally buttermilk came from the liquid that was extruded from the butter making process. Nowadays, buttermilk is regular milk that has had an acid added to it.
• Yogurt – Yogurt can come in full fat (similar to whole milk nutritionally,) low fat (similar to low fat milk nutritionally), and non-fat (similar to skim milk nutritionally) has had two friendly bacteria added.
• Sour cream is made from _ and _ that has had lactic acid bacteria added to it
• Crème fraiche is made from heavy cream that has had the lactic acid bacteria added.

Cream

More on Milk:

• Milk is homogenized to create even sized fat globules that are buffered with proteins and emulsifiers that prevent the from coming together and floating to the top of the milk.
• Pie crusts made with milk will get more brown than those made with water.

Learn More:

• Air Pressure & Baking
• Proteins
• Carbohydrates
• Fats
• Leavening
• Thickening Agents
• Chocolate
• Specialty High Altitude Baking Tips

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