In Sicily, ricotta is made from ewes' milk. In the United States, it is most always made from cows' milk. It should be pure white, creamy and smooth. Never should it be yellowish, watery or grainy. Excellent ricotta is made by Caseficio Gioia, a local producer. It is available at Alessio's Delitaliano, 203 N. Larchmont Blvd., Los Angeles.
If you want to make ricotta at home, here is a simple recipe for a ricotta-style cheese:
* Heat 2 1/4 gallons whole milk evenly in large pot, stirring occasionally, to 185 degrees. Remove pot from heat and add 1 cup plus 2 tablespoons 5% vinegar. Stir well. Milk will curdle. Cover pot with cheesecloth. Let stand, unrefrigerated, overnight.
* Line colander with 2 layers of cheesecloth, cut generously enough to rise above sides of colander. Pour contents of pot through colander and allow to drain freely about 1/2 hour.
* Lift cheesecloth and solids out of colander. Twist and squeeze until liquid begins to run milky. Turn cheese out into bowl. Add about 1/4 teaspoon sea salt. Cover and refrigerate.