Classic Yogurt
Makes 1/2 gallon.
Note: "The simplest incubation chamber, and my go-to, is a small, well-insulated ice chest," writes Gianaclis Caldwell in "Homemade Yogurt & Kefir." "Choose one that easily holds your incubation vessel with a little extra room to tuck jugs of warm water and/or towels around the vessel. I place a towel in the bottom of the ice chest, set the vessel in the middle of the towel, and tuck another towel on top and around the vessel. If the room is cool, I fill one or two jars with warm water (one or two degrees above 110 degrees) and add them to the chest. When tucked in like this, yogurt will ferment quite evenly." Powdered yogurt culture is available online at sources that include culturesforhealth.com and getculture.com.
• 1/2 gallon dairy milk
• 1/8 c. fresh plain yogurt with active cultures or 1/8 tsp. powdered yogurt culture (see Note)
Directions
In a large stainless steel saucepan over medium heat (or in a large stainless steel double boiler set over gently boiling water), heat the milk to 180 degrees and hold it there for 10 minutes. Remove the pan from the heat and let milk cool to 115 degrees.
Add the culture. If using fresh yogurt, combine the yogurt and 1/4 cup of the warm milk in a small bowl and whisk until smooth, then whisk the mixture into the rest of the milk. (If using powdered culture, sprinkle it on top of the milk and let it sit for 1 minute, then whisk it in).
Pour the ferment into a tempered glass jar with a lid. Cover and incubate at 110 degrees for 8 to 12 hours (see Note). Do not stir. Stop the fermentation process by chilling. Place the incubation vessel in cold water (fill the sink with cold tap water, or fill a bowl with ice water) until the yogurt is cool. Move the yogurt to the freezer for 1 to 2 hours, then store in the refrigerator.