Today I made a fairly large batch of mozz which took two pots. I then reserved the whey as it drained in a different pot again. My mozz was pretty much successful though it drained out a fair bit of 'milk' as I worked it (saved back into the reserve pot)
So three pots of whey from the same day's make, from raw milk from the evening before.
Anyway I used all three pots to see what ricotta I could get off them.
Pot 1 - the smallest and the one I had used to heat the curd for pulling, was milky, salted, and probably overacidified - essentially I got no ricotta from this at all.
Pot 2- I followed advice from a member here (susan I think?) and dropped in a little vinegar (I just used a capful to probably 6-8 litres of whey) and a spoonful of salt. I got some relatively pleasing ricotta from this, though smallish curds, but certainly a reasonable and useable yield.
Pot 3- About the same amount as pot 2, maybe a litre or 2 less. I added nothing at all and got the best results of all. The ricotta curds were fluffier and just kept on coming.
What all that means I have no idea as a new cheesemaker, but it made me go hmmmmmmmmmm, and thought others might find it interesting.
I should have taken photos but I was just too tired by that stage of the day.