Supplies for making yogurt.1. 1/2 gallon whole milk.
2. 3 clean glass jars and covers. (I use spaghetti sauce jars.)
3. Thermometer that can read up to 200º.
4. Double boiler for milk. (Two pots w/cover)
5. Steamer or large pot with cover (for sterilizing bottles and caps)
6. 1/2 cup yogurt starter (yogurt with live culture)
7. Cooler large enough to hold glass jars. (Foam coolers are OK)
8. Colander to strain completed yogurt.
9.Clean cloth to strain completed yogurt.
10. A bowl to collect whey.
11. Stirring spoons, funnel, twist tie.
1.Warm up the milk and sterilize the bottles
Put some water in the bottom pot of the double boiler. You don't need to add too much water, remember the second pot that holds the milk will affect the water level in the first
pot. Put the pots on the stove and get cooking. Stir occasionally, you want to get the milk heated to between 185º to 195º.
Meanwhile place glass bottles in another pot with water and get that boiling. Fill the pot about half way and let the steam kill the germs in the part of the bottles that stick out of the water.
Once the bottles are steamed, take them out of the pot and be sure to keep the hot water! Turn off the burner. That water will be used later.
In this photo, the milk is heating up to 195º while the bottles are steaming on the back burner.
Hint: For thicker yogurt, add 2 Tbl powdered milk to the 1/2 gallon of milk before heating.
2. Cooling the heated milk
Once the milk is warm enough, remove the pot with the milk from the stove. Keep the hot water from the lower pot and add it to the hot water in the bottle sterilizing pot.
Add cool water to the lower pot,
place the pot with the heated milk into the lower pot, (see photo) start stirring and cooling the milk down to 130º. Do two or three water changes to the lower pot. Save the warm water by adding it to the bottle sterilizing pot.
Cooling milk and sterilized bottles.
3. Adding the starter
Stir up yogurt starter, after the temperature of the milk drops to 130º, add starter to the milk. Stir thoroughly. The temperature will drop to about 122º. Add the warm mixture to the sterilized bottles. Cover with sterilized lids.
Hint: The starter tends to clump at the bottom of the pot, save some space to add the last of the mixture to each of the three bottles.
Adding the mixture to bottles, the filled jars, into the cooler
4. Place the filled jars in the cooler.
This is where the heated water that was used to sterilize the bottles gets used. Add enough warm water, (130º to 122º) so that the bottles are surrounded, but below the lid rims. If the jars are not all the same height, you can have the short bottles placed on something to raise it up. Close the cooler to keep things nice and warm.
Keep the cooler closed for at least three hours. Depending on the starter and your taste, the completion times will vary. The longer the yogurt sits, the more tart it becomes.
My yogurt starter is very mild, so I let it sit overnight. As long as the water temperature stays between 104º and 130º your yogurt cultures should be happy.
Hint: At the three hour point pick up the jars and shake it. That seems to distribute the yogurt and make it firm up better, otherwise the bottom of my jars seem to have a thicker yogurt. The three hour point is also a good time to check the water temperature and to take a taste test of your yogurt with a clean spoon. (Done or more time needed? It's up to you.)
This batch has been sitting overnight (12 hours) I shook it once at the three hour point and did not add warmer water. At the end of 12 hours the water was still about 100º. You can see the yogurt and whey.
5. Making Greek Yogurt
For a firmer yogurt like Greek yogurt, the trick is to strain out the extra whey. Use a colander, and a clean white cloth. The cloth is tied up with a twist tie, the bowl under the colander catches the whey. (We use the whey to add to our dog's food, and for bread making) I let it drain for one hour. If it drains for two to three hours, it gets to the consistency of cream cheese.
The final product, about two pounds of homemade yogurt and more than a jar of whey.