Yogurt

Ingredients

Preparation

• Scald milk (heat to over 180^oF) and then cool to 120^oF.
• Add yogurt to cooled milk and mix thoroughly.
• Place in an oven which has been warmed to 110^oF to 120^oF.
• The yogurt will set in about 6-8 hours.

Notes

• There are only a few variables to keep in mind when making yogurt, and the whole process can be automated quite precisely so that you can make yogurt frequently with little overhead.
  • The variables are the kind of milk (organic, fat content, etc.) and the starter yogurt. One additional ingredient is milk powder ... add this if you need to prefer thicker yogurt.
  • Automating the process is straightforward after some trial and error. Heating the milk in a microwave oven enables you to time the event precisely without watching to make sure that the milk does not boil over. The time obviously depends on the initial temperature of the milk, the power of the microwave oven, etc. -- for example, I find that it takes me about 6 minutes to heat a quart of milk to 200^oF. Bringing the (regular) oven to about 110^oF takes only a couple of minutes. Use a cooking thermometer (a programmable one that will beep at a given temperature is ideal) to make sure that the milk and the oven are at the right temperatures. Anything over 130^oF kills the bacteria, and under 100^oF is not warm enough.
• Scalding milk is necessary to destroy both the bacteria and enzymes. If the milk being used has been pasteurized, then this has already been done and may be unnecessary. In this case, you only need to heat the milk to about 120^oF. Click on the respective links to learn more about scalded milk and denaturation.