Yogurt / Cottage Cheese experiment

[YoGal]

Hi, everyone!. I'm new here.
I joined because I have a question about a little "experiment" I did a couple of days ago.

I don't (cannot) drink milk in its original form, so I only consume yogurt and aged cheeses. I've been making my own yogurt for several years. Sometimes from a Yogurmet starter, sometimes from store-bought yogurt, and sometimes from a previous batch as a starter. So I'm quite experienced at making yogurt, and it comes out perfect every time.

The other day I went to a restaurant, and one of the sides dishes was cottage cheese. Of course I didn't eat it there, but I brought it home thinking I might be able to "fix it" and make it edible. So here's what I did:

I took the about 3/4 cup of cottage cheese and rinsed it under running water. I was left with only the curds. Then I added one cup of whole milk, and blended the whole thing with a stick blender. Then I used the resulting thick liquid to make yogurt following my usual procedures (heated milk to 185 F, let cool down to 110, added 1 Tablespoon of previous batch of yogurt , put it in the yogurt maker, let incubate for 20 hours).

After the 20 hours, I looked at the results and saw that there was a lot of liquid at the top. I thought that something might have gone wrong, but it didn't smell bad, so I put it in the fridge as usual. The next day I took it out, and the liquid layer (about one inch deep) was still there on top. So I discarded the liquid, and was surprised to discover that the rest of it is not soft like yogurt. The best I can describe the consistency/texture is like a very dry creme cheese, or perhaps a dry farmers cheese (a.k.a. dry curd cottage cheese).
I tasted it, and it's quite tart and grainy - not smooth.

So my questions are:
WHAT did I make???
Why is it so grainy?
Do you think the yogurt bacteria from the starter did its job and cultured the whole thing?

Sorry for the long post, but I felt that I needed to be detailed in order to get helpful opinions.
Looking forward to your replies. 

[smilingcalico]

Short answer, I don't know what the heck you made! 
  The liquid on top must be whey (it's the liquid left after the solids have coagulated out.  You could just pour it off.
   I've had a batch of cheese go grainy before, but it was caused by the milk still moving while the curd was setting (at least that's the suspicion, the whole batch failed).  I'm not sure what the graininess is, someone here with a more scientific background may be able to answer that.  It's not likely that the small amount you made was still in motion.
  The tartness sounds like over acidification, but not being able to taste it, I couldn't say for sure. 
  In the end, if it appeals to your tastebuds, do it again.  If not, chuck it. 

[KosherBaker]

Hi YoGal.

First of all welcome to the forum. Second order of business is some basic terminology. In Cheesemaking there are two basic starter cultures:
1. Mesophilic
2. Thermophilic
Mesophilic culture is used in most cheeses including the cottage cheese. It does it's magic at room temperature. And it can be purchased in concentrated form or as Buttermilk from your favorite grocer.
Thermophilic culture is used to make Yogurt and some very hard cheeses. It does its magic at a much higher temperature of 115F which is why you are using the Incubator (i.e. the Yogurt Maker). Thermo = Heat.

Now to address what you have made. You have made a Lactic Acid Coagulated curd. It is basically an initial step (or more like set of steps) in some cheese production or other. At this point you can make your own Cottage Cheese from it, or American Neufchatel and maybe even Feta.
What you most definitely did not make is Yogurt.
Here are some links to some recipe sites that may clear things up, further. May I also recommend reading the archives for the many many forums on this amazing site. I'm in the process of doing that now and can't even tell you how much amazing info is available here.
Cottage Cheese Recipe
U.Guelph Recipes
Peter Dixon

[YoGal]

Thanks for the comments.
Yes, of course I know I didn't make yogurt. That's why I'm asking what the knowledgeable people here though Ii ended up with, given the process I followed.

I drained it further (didn't give a lot of whey) and it really looks and feels like dry curd cottage cheese, just a little tarter.