skyr (for songstress1973)
For the skyr I made on Monday, I followed the basic directions in the new Complete Anachronist on skyr...
Heat a gallon of skim (non-fat) milk in a heavy pot until it reaches 185°-195°. To keep the milk from scorching, you either have to stir constantly the whole time, or do it over very low heat in a heavy pot. I opted for the latter, 'cause with the lazy. I used a digital food thermometer that can stay in the milk, and has a high/low temperature alarm, so I pretty much just set it for a high of 187° and came back occasionally to stir until the alarm went off. The recipe said keep it at that target temp for 10 minutes, so I did. I think it got up to a high of 190° or so. After 10 minutes, shut of the stove, and let it cool down until just above body temp (100° - 102°), then stir in 2 T of your starter culture. This time I used Siggi's Icelandic Skyr, which our local New Seasons Grocery carries (I think Whole Foods does too). In the past I've used a high-quality live-culture Greek yogurt if skyr isn't available. Stir for a bit, and let it sit for a few minutes, then add 4 drops (I used 6 since mine's really old) of rennet dissolved in 1T of warm water to the pot. The recipe said stir for 10 minutes, I think I got tired of it after 4-5. Then you just let it sit until the curd has set. The recipe suggested 5 hours, mine took between 7 & 8. You know it's "done" when you can see the clear whey separating from the curds along the top and sides, and the curds will pull away from the side of the pot a bit. During the waiting period, the warmer you can keep the pot, the sourer it will come out, since the lactobacilli like it warm. In the past I've put a blanket around the pot, this time I counted on the heaviness of the pot and the fact that I was doing other cooking on the stove to keep it warmish.
After the curd has set, you fish it out with a spoon into a sieve lined with cheese cloth (I use muslin) and drain as much of the whey off as you can, then tie up the cloth and let it hang (over a pot to catch the whey, or outside) for 12-24 hours. I like to save the why for adding to fermenting projects like kraut since it makes a big difference in how fast fermentation gets started. We hung it up around 9 PM, and I cut it down in the morning when I made breakfast. It comes out quite firm, much harder than yogurt, and it got more sour over night. I got about 2 1/2 quarts of whey out of the process.
The Icelanders used the leftover whey for making syra (a soured whey beverage) and for preserving food in.