Homemade Yogurt and Kefir
Our homemade yogurt and kefir class (part of the Preserving the Harvest series) on Tuesday night was was so popular that I'm just going to go ahead and post the instructions here. Everyone at the class agreed - there's just something about the taste of fresh, creamy yogurt made in a glass jar. Enjoy, and feel free to write in if you have any questions.
Homemade yogurt (foreground) and kefir (background)
Homemade Yogurt
4 cups (1 quart) milk
¼ cup yogurt with live, active cultures (“starter”)
Medium size heavy-bottomed pot
Double boiler (optional)
Stirring spoon
Thermometer (with range between 110 and 185 degrees F)
Quart-size mason jar with lid
Heat milk to 185F. If you use a double boiler or a mixing bowl that fits inside another pot to prevent your milk from scorching on the bottom, you should only have to stir it occasionally. If you heat the milk directly, use your heaviest pot and stir occasionally, monitoring the temperature (185 is the temperature at which milk starts to froth.)
In the meantime, warm the starter. Let the starter yogurt sit at room temperature while you are heating the milk. This will prevent it from being too cold when you add it in.
As soon as the milk reaches 185, cool it to 110F. The best way to do this is with a cold water bath (place the pot in the sink so water and ice come halfway up the pot). This will quickly and evenly lower the temperature. Stir occasionally. For the cultures to incubate, the milk should be at 110F.
Add the starter yogurt and stir very well (a whisk is helpful).
Pour the mixture into a quart-size mason jar. Make sure to get any clumps into the jar and tightly screw on the lid.
Allow the yogurt bacteria to incubate at 100F for about 7 hours (or within the 6-12 hour range), depending on how firm you want the yogurt to be. Keep the yogurt warm and still to encourage the yogurt to firm. Do not jostle! Some places to incubate the yogurt include:
-in the oven with the pilot light on;
-in a hot water bath in the sink (keep refilling hot water);
-wrapped in a sleeping bag;
-wrapped in a towel next to a hot water bottle;
-in an insulated cooler (use a towel or a few bottles of hot water to fill any empty space);
-in a thermos;
-in a crock pot on low
You can check the temperature periodically with the thermometer if you like. After a certain amount of time, depending on how warm it is and how much starter you used, it will begin to set up and look and smell like yogurt. You will see clumps forming and whey, a thin yellow liquid, will collect on the top. You can pour it off or stir it in before eating your yogurt. The longer your yogurt incubates, the more tangy it will become. Refrigerate when you’re ready and store for up to 2 weeks.
Troubleshooting:
If the yogurt hasn’t thickened after 6-12 hours, you can warm it up by filling the sink or a large pot with a hot water bath and setting the bottle of yogurt in it. Cover with a towel. Leave for about 30 minutes to warm it up, then place in the warm place again for another 4-8 hours. If you like, add more starter to the yogurt and stir it in before putting leaving it incubate again.
Homemade Kefir
Follow directions for yogurt, except use 5 grams (1 packet) dried kefir culture, and cool milk to 73-77F. Add culture to milk, stir well, and incubate on the countertop for 24 hours. Stir and refrigerate.