There is nothing quite like homemade yogurt. You control the ingredients and you can making it as tangy or as mild as you want by adjusting the incubation time.
Pour the milk into the inner pot of the Ninja Speedi. Select Sear/Sauté and heat the milk to 182-185°F. Whisk frequently during the heating process to avoid scorching on the bottom.
Cool the milk down to 104℉. You can do this by simply leaving it sit at room temperature for a few hours or put it in a sink full of ice water to cool faster. You can also remove the pot from the Speedi and whisk frequently to cool faster without using an ice bath.
Add the yogurt starter and whisk well. Place a piece of parchment paper over the top of the inner pot and tuck in the sides. Select the sous vide function and set the temperature to 120℉ and the time for 8 hours. Hit start.
After the 8 hours is up, remove the inner pot and place it in the refrigerator to chill for at least 6 hours. After chilling your yogurt is ready to serve. See recipe notes for making Greek yogurt.
Refrigerate any unused yogurt in airtight containers. Your yogurt will last up to 2 weeks.
Making Greek YogurtTo make Greek-style yogurt, strain the yogurt after refrigerating for at least 6 hours. You can use a (affiliate link)flour sack or a (affiliate link)yogurt strainer. The yield of Greek yogurt will be less than regular yogurt. You will get around 5-6 cups of yogurt per gallon of milk. The yield depends on how long you strain it. Yogurt YieldThere are several factors that affect the end yield of your yogurt. There is a little evaporation when heating the milk in the first stage of yogurt making. So, I would plan on about 15-16 cups of yogurt from each gallon of milk. If you strain the yogurt for Greek yogurt, you will have significantly less yield. In my experience, this is about 30% less yield than regular yogurt, but it really depends on how long you strain it and how much whey is extracted. Plan on around 5-6 cups of Greek yogurt per gallon of milk if you strain it overnight.