urgent ricotta making questions

Yes, rennet is used to make the first cheese, no matter whether it's cow, sheep or goat's milk that is used. The curd is cut and extracted from the whey. Then the whey remaining in the cauldron, along with whey drained from the curds, is reheated to a much higher temperature than that for making the original cheese. Sometimes more fresh milk is added but a very small percentage. The reheating causes any residual proteins to coagulate and turn into. . . ricotta! But no additional rennet is used. You can read about it on my web site: http://nancyharmonjenkins.com/posts/ricotta-a-true-story/

Is rennet used to make the curds for the first cheese? if rennet isn't used, what causes the coagulation and resulting whey? And is the re-heating of the whey the catalyst for the ricotta curds?

PS: No rennet goes into real ricotta.

I'm glad to see a lot of confusion (and a lot of good sense) on this thread. True ricotta is not made from acid added to whole milk, or cream or any other type of dairy. That, as someone has observed, is nothing but curdled milk. It can be delicious but it should not be confused with true ricotta which is made from the whey left over in cheese-making. That whey, sometimes with the addition of a little more milk--but never with acid added--is reheated (re-cotta, re cooked) so that the residual protein clumps together and makes something that looks, yes, like cottage cheese--but Richard Nixon would never have eaten it with ketchup (those old enough to understand my reference, please raise their right hands). And that, drained of excess whey, is true ricotta--and a miracle of cheese-making, fresh and warm, first thing in the morning. And I wish more American cheese makers would practice this simple art.

Thanks guys. It makes sense that true ricotta would use rennet, but since I'm just making a makeshift ricotta in an 'emergency' situation, the vinegar method is good enough.

I ended up adding apple cider vin, then heating the salad cream to just below boiling. The curds were small, but clearly separated from the whey, the whey was clear. So I took it off the heat and left it for 10 min before straining and hanging the curds for an hour. Mixed in a generous pinch of salt and it's ready. It turned out fantastic! Beyond fantastic! Perfect ricotta texture and taste for this recipe. Possibly a bit more rich tasting than commercial ricotta.

Thanks everyone for your input, links to the recipes and everything.

Now, any thoughts on what to do with this leftover whey? Also, where to buy better cheesecloth? Mine was far too coarse and needed four layers to stop the curds from falling through.

Whether or not this is true ricotta, you'll need about 1/3 cup vinegar per 1/2 gallon of whole milk. Cream should work, but not the ultra-pasteurized stuff (UHT). You'll need to heat the cream to 200F or 93C. I have used this recipe and it has worked for me,
http://www.thekitchn.com/how-to-make-homemade-ricotta-cheese-23326

The higher the fat content of the dairy that you use, the creamier the cheese. A leaner dairy will make a grainy product. But from all I tried and read, UHT dairy just doesn't work and yields a less than satisfactory cheese, if it curdles at all.

Plenty of homemade ricotta recipes use vinegar. David Lebovitz includes cream http://www.simplyrecipes.com/recipes/homemade_ricotta_cheese/

I’m about 99% sure that true ricotta is not made by adding acid. ‘Ricotta’ means ‘cooked twice’. If I remember correctly, you begin with whole milk to which rennet is added. Curds form and that is cheese. Then, the whey is cooked again (I’m not sure if more rennet is added at this point), and more of the milk solids coagulate and are scooped into baskets to drain. That is the ‘ricotta’. I think the idea of adding acid to milk is some sort of American shortcut.

Really? I've never needed rennet before and I've made this dozens of times. It's always just called for citric acid or vinegar. Given that ricotta was originally made from hard cheese whey and acid... well, the definition of words change over time and I learn something new everyday.

Thanks for the link.

I don't think my rennet is viable, so I'll just try 1 Tbs apple cider vin for the litre of cream and see what that does. Now, to get the temperature right...The recipe you linked to seems a bit cool, but I'll heat it to that temp and see how the cream acts before adding the vin.

Thanks again.

You need rennet to make ricotta, not vinegar. Vinegar will just give you curdled cream. Having said that, here’s a recipe for a ricotta substitute that might help you out:
http://www.foodnetwork.com/recipes/ina-garten/homemade-ricotta-recipe/index.html