Actually, 30-min mozzarella was my first cheese, but since I had a gallon of milk left and a ton of whey after I was done, I figured I'd give whey ricotta a try! I added 2 cups of whole milk to the whey and followed Ricki Carroll's recipe. I think my yield was about 3 oz, which doesn't seem like much to me - not sure if I did something wrong or if that's really all you can expect to get from whey ricotta. Anyway, it was quite tasty but just a tiny bit sour.
I then used the rest of the gallon of milk to make whole milk ricotta - mixed citric acid into the milk and then heated to around 200 degrees, stirring frequently (per Carroll's recipe), let it sit for 10 mins and drained. I got a pretty good yield I think (19-20 oz after it had been drained very well). The whey was a little opaque - I wouldn't have called it milky, but it wasn't quite as translucent as the whey I had after making the mozzarella.
This version was absolutely delicious, IMHO. A 1000% improvement over store-bought ricotta, and so inexpensive in comparison! Around here, a decent store brand of ricotta is almost $5 for a 15 oz tub. I paid $2.32 for my gallon of milk and got over a pound of ricotta, and much better tasting ricotta to boot! I used it for the cheese filling in my Italian meatloaf and everyone noticed the improvement. Can't wait to try ricotta salata!
One question for all you pros, though - where in the process could/should I have added CaCl? I couldn't find the info in Ricki's book and I didn't want to add it at the wrong time and mess up the cheese. Would I have gotten a better yield if I used it?