The first time I had pretty good curd formation - it was a little loose, but not bad. Everything was going well until I started heating up the curd to stretch it. At that point it completely dissolved into the water I was heating it in. I thought that maybe the water was too hot, but by the time I realized what was going on it was too late. I also heard that this could mean the curd was not acidic enough?
The second time no curd formed. I used 2tsp of citric acid rather than 1.5. Also, the rennet tablet and acid were dissolved and added in warm/hot water, not cool. After adding the rennet, I let it sit for 5 minutes then another 5. The whey and curd separated and the curd fell to the bottom of the pot. I reached my hand in and it was a bunch of little globs of curd. No good formation.
I am trying to decide if I should give up with this milk or if it is something in my process... Any help would be greatly appreciated.
Edit: Also, the second time I used an iodine (1%) /water solution mixed at 1tbs iodine/5 gallons water for sanitation as I do with brewing. I didn't do this the first time - some of the solution (an ounce or less) likely made it into the milk could this be part of the problem?
I'm really thinking that your problems are from the process you are using to make the cheese itself. I know that many people are successful using pasteurized and homogenized milk from the grocery store, so I really don't think your milk is the problem at all. I use raw milk and don't pasteurize it ahead of time and it turns out great with good yield.
I'm thinking you may be stirring the milk too much after adding the rennet, as that can break up the curd or prevent it from forming. Also, you must use cool water to dissolve the citric acid and the rennet. You may have damaged the rennet by using warm water in your second batch. It is pretty delicate, especially the liquid stuff.
I liked Ricki Carroll as a starting point with cheesemaking, but I have to say that every time I see her "30 Minute Mozzerella" recipe, it is different. I've probably seen about 5 permutations of the recipe, all on her website and in her books. There's a reason the recipe keeps changing, methinks!
Here's how I make mozzerella using citric acid:
1 gallon milk
2 teaspoons citric acid, dissolved in 1/4 cup cool water
1/4 teaspoon liquid rennet, dissolved in 1/4 cup cool water OR 1 Junket rennet tablet, dissolved in 1/4 cup cool water (I've used both rennets and had good results)
1 teaspoon cheese salt (optional)
I use a double-boiler method to heat my milk. Place a 2 gallon pot inside a slightly larger pot, with hot water in the outside pot. This helps prevent scorching your milk and helps the milk heat up more evenly.
Dissolve your rennet in cool water before you start to warm the milk.
Set another pot of water to heat up to 170-180 degrees. It will form bubbles on the surface of the pot, but won't actually be simmering (breaking bubbles).
Put your cool/cold milk in the 2 gallon pot and mix the citric acid in thoroughly. Heat the milk to 88* F - it will start to curdle. Stir while heating so that the milk is evenly warmed.
Gently stir in the rennet with an up and down motion (don't swirl your spoon through the milk, as it can break the curd up/prevent good curd formation). Quit stirring once it is well blended, but continue to warm the milk to 105*. Remove the inner pot from the double boiler once the milk reaches 105*. If you do not have clean break yet, allow the pot to set undisturbed. This can take 5-10 minutes with the curd being the consistency of thick yogurt and the whey should be fairly clear, though yellowish-greenish.
I then scoop the curds out into a pyrex bowl. Ladle some of the almost-simmering water over the curds and using a slotted spoon, gently, very gently, lift them around and fold them over each other as they warm. The curds are tender at this point and you don't want to break them up at all. As the water cools, dump it off and add more hot water.
The curd will start to change from a yogurt-like mass to a warm taffy-like substance. At this point, you can start taking it out and stretching it. If it is too hot to handle (use a pair of rubber gloves or two pair of latex exam gloves), I will use two spoons to lift and stretch it until it has cooled enough to handle. If the curd strands break, return them to the hot water (replace this as it cools), then try again.
Sometimes I have to heat them several times until the curd is stretching like a taffy pull. While it is still stretchy, I place it on the countertop and sprinkle the cheese over it, knead the salt in, then heat and stretch some more. The cheese is done when it is smooth and shiny.
Like kneading bread, it is a feel thing.
You can also use your microwave to do the heating. I nuke the curds/work them, in 2 batches. The first heating is for about a minute, then I do 30 or less seconds for 3-4 more times. Whatever it takes to get the curd stretching well.
Don't give up on mozzerella. IMHO, it is one of the funnest cheeses to make (I love being up to my elbows in the stretching!), and one of the most gratifying, as you can be eating on a pizza the same day you make it.