Homemade pizza was on our New Year's Eve menu, and after boasting of our cheese-making success this past fall, we volunteered to make a batch of fresh mozzarella to go on top. But as you can see in the photo above, something went rather wrong...
Everything seemed to be normal up until the step where you microwave the cheese curds. Instead of melting together into an elastic ball of yummy mozzarella, the curds kept breaking into smaller and smaller grains, close to the consistency of ricotta. We kept checking the temperature of the cheese with an instant-read thermometer, and we were definitely getting it hot enough.
The cheese became a little firmer and more cheese-like after we gave up and let it sit for a while, but trying to microwave it again didn't do anything. It was still delicious on pizza, but just not quite what we were going for.
We have a few theories about what might have happened:
1. We did one step differently than the previous time: after adding the rennet and letting it sit, we re-heated the curds and whey to 105° while stirring gently. This was a step in the booklet that came with our kit that we skipped the first time because a note later in the booklet and an instruction on the company's website both said this step was optional.
2. We didn't have a good spoon for scooping the curds out of the whey. As a result, the curds became more broken up and we scooped up a fair amount of whey along with the curds. In our first cheese-making experience, we were able to drain off the excess whey as the cheese came together. This time, it seemed like the whey mixed back in with the curds and made it soupy.
3. Our milk was old, as in a day before the expiration date. We're not sure if this would affect the cheese-making, though. By the way, the milk was definitely not ultra-pasteurized.
4. We accidentally used an aluminum pan. Aluminum can react with the citric acid to create an off-flavor and discoloration, but we also wonder if it might have interfered with how the curds formed. Since everything seemed fine up until the microwaving stage, we're thinking this wasn't the problem. But you never know... (P.S. As far as we could tell, our resulting ricotta tasted and looked fine!)
Our best guess is that we stirred the curds too much, both during the re-heating stage and during the scooping stage. We're not sure why this would make such a difference - you'd think the cheese would just come back together after being heated in the microwave - but the company mentions over-stirring as the culprit behind a few different cheese-making mishaps.
Next time, we'll go back to skipping that re-heating step and maybe try upping the amount of citric acid.
Any thoughts?
Related: Top Five Things to do with Ricotta
(Image: Emma Christensen for the Kitchn)
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We had the same thing happen in my food science class when we made mozzarella.
The milk you used was ultrapasteurized (UP), not pasteurized (a lot of milk is marked as "pasteurized" when it's actually UP). UP is brought to a much higher temperature which denatures the casein protein to such an extent that it won't form a curd, as you've just found out.
There's nothing you can do to fix it. Remember which milk you bought, and try a different one next time. All (nearly all?) organic milk on the market is UP.
In the mean time, you've essentially made ricotta so enjoy!
We had the same thing happen to our first attempt at making cheese.
On the second try we made a couple changes:
1) Use double the rennet. We used a half tablet vs. a quarter.
2) Don't stir so much after adding the rennet. We read something about it "cutting" the curd if you do stir it too much.
3) Continue heating to 105 degrees (like you did the first time).
The second batch came out perfectly, so who knows...
I haven't made it yet, but it is something I've been wanting to do. Here is the recipe I was planning to use.
http://animalvegetablemiracle.com/Mozzarella.pdf
It specifically mentions not using Ultra Pasteurized milk.
Here are photos from my food science lab when we made the broken mozzarella:
http://flickr.com/photos/jdickert/sets/72157604612858084/
Check out the last few photos. The one that broke was 2% milk, store brand. It was marked as pasteurized but was actually ultrapasteurized.
Using *not* ultra pasteurized milk, I have made ricotta three times and a rubber ball once using Rickis 30 minute Mozzerella package and recipe.
According to my web search, I'm not the only one having issues.
One suggestion is to let it sit for 30 minutes to get more acidic and then test a small sample to make sure it's acidic enough to heat and then stretch. The testing a sample seems like a really good idea- especially after creating my unedible rubber ball.
Oh, I started out on my mozerella adventure from your earlier post! Even though I've only had failures, it's a fun process.
I've had this happen.
you need to use a stainless steel stock pot. also once you add the rennet, stir it only for a few minutes to mix in the rennet, then do not touch it at all.
lastly, I had the most success using raw milk. if you can obtain it in your area, it rocks.
http://www.eatitatlanta.com/2008/12/23/mooozarrrreeeellllaa/
@anothersplash - unless you used raw milk (that you know for certain is raw, like you bought it at the farm), it was probably ultrapasteurized. You really have no way of knowing, since labels are not always accurate. So dont go by what the label says. Ricki Carrol said in one of her cheese making workshops that this is a very common problem.
So I'm not the only one making either soupy ricotta or rubber balls. I'm going to try adding more rennet, stirring less and try other brands of milk. And maybe an email to Ricki.
What a bummer! Wish I could offer advice but I'm completely uninitiated when it comes to cheese making.
Now cheese eating, is another story all together. If you ever have troubles in that department be sure to call me!
I took a workshop with Ricki and she covered this problem extensively. In fact as others here have said a lot of milk that is sold as pasteurized is actually ultra-pasteurized. You can call the processing plant to find out what temperature they use.
Better yet use raw milk. It comes out perfectly every time.
Same thing happened to me. Yesterday I made my first batch, and it was close to crazy putty. I used more than one tablet of rennet and what was pasteurized milk. My daughter (in the restaurant/baking business) said that if the recipe doesn't come with the "science", then I'm guessing at results. She said to go to Alton Brown right away!
I'll let you know if there are any pointers.