Quark (meaning “curd” in German) is an ancient form of soft cheese that may date back over 2000 years. It is the consistency of sour cream or yogurt, making it a popular spread. But quark can be used in a large number of ways. It can be substituted for cream cheese in cheesecake, mixed with dried fruits for a quick breakfast, or blended with herbs and salt for a tasty cracker spread. Quark is generally made with skim milk, but higher-fat milks can be used, and a bit of cream can be added to the final product to create a creamier cheese.
Turn off the heat when the milk reaches temperature and add the cultures by sprinkling them onto the surface of the milk and allowing them to rehydrate there for 4 to 5 minutes. Then incorporate them into the milk using an up-and-down motion for about 30 seconds.
Cover and maintain the milk at 72°F for 30 minutes.
Add the diluted calcium chloride and stir for 1 minutes in an up-and-down motion. Repeat the same process with the diluted rennet.
Cover the milk and let it set at room temperature for 12 to 18 hours, or until there is a clean break and a slight layer of yellow whey floating atop the curds.
Return the curd to 72°F, and begin cutting it into 1/2-inch pieces. Once the curd is cut, remove it from the heat and gently stir the curds for 5 minutes.
Let the curds sink to the bottom of the pot, but maintain the temperature. Ladle off the top layer of whey until you can see the curds at the bottom.
Line a colander with butter muslin and begin ladling the curds into it. Let the curds drain for about 8 to 10 hours, or until the desired consistency is reached.
Put the drained cheese into a bowl and mix in the salt, adding more or less to accommodate your own personal taste.
Store your quark in a covered container in the refrigerator, and use within 2 weeks.