Houston, we have a problem

[sashap]

Hello fellows.
I'm Alex, this is my first post on this forum.
I was lurking here a while and studied everyone's stories, yesterday I tried for the first time to make mozzarella with REAL starter cultures!... and failed... Before that I made only the mozzarella with the citric acid, without any culture.

I used the Gianaclis Caldwell "long" recipe, wanted to train for more serious cheese, but at some point something went wrong.
I will describe the steps, and maybe someone will be willing to help an absolute beginner like me. Also, I attached all the photos that seem relevant to me, if You need more information, I'll be glad to provide it.

I used fresh raw milk from the local farmers (yeah, I'm very lucky).
1. I warmed 1 gallon (4.5l) of milk to 80F (27C) in water bath, sprinkled the culture on the top (~1/8tsp) and waited for it to rehydrate for 4 minutes, then stirred for 1 minute. The culture: http://cheeseandyogurtmaking.com/cheese-making-supplies/cheese-making-cultures/mesophilic-cheese-starter-culture-for-cheese-making.html . Used Mesophilic instead of Thermophilic, but kept an eye on the temperature to keep it at 32C.
2. Increased to 90F (32C), left it untouched for 70 minutes.
3. Stirred in the rennet. The dosage was 24 drops per gallon (approx .75g) of 1:10,000 liquid animal rennet from Bulgaria. It was very ok in pair with the citric acid, and it's surely not expired. I was using 8 drops (.25ml) for 1.5l of milk and the result was perfect.
4. Here comes the problem. I was going to measure the flocculation time, but it was completely absent! I was spinning a small plastic bowl every minute, then every 10 minutes, after 1.5 hours I gave up. It wasn't coagulating at all. After some hours the milk started to coagulate, but the curd had a really strange form. There was a lot of cream on top and the curd was "ripped" (I'll try to upload a photo).

When the curds were firm to cut, I cut them and followed the remaining steps. But it was too late, the curd was obviously too acidic (at this point it should be still sweet, this one was sour) and it was crumbly. I drained it in cloth and pretend that I was going to make cottage cheese

I want to figure out what I did wrong and how to correct my process.
My guess is that I was using too small an amount of rennet. Or maybe I need to let the milk to ripen for a longer time...
I have no means to measure the pH for now, so I cannot tell when it drops for .2. I ordered some pH strips of small range to at least measure the approximate pH and to see where's the problem, but they are still on the way.

[sashap]

Unwrapped the "cottage cheese", the texture and the taste are really really nice. Too bad I was going to make mozzarella...

[Denise]

You'll have to wait for the experts to tell you what went wrong, but my amateur take is, If the end result is edible, it was a successful make.

Just don't tell anyone it was supposed to be mozzarella! 

[sashap]

Thanks, Denise. I'll humbly wait for some expert passing by and give me some indications.
Made yesterday another batch of direct acid mozzarella and it was good, officially the cultured batch "was supposed to be" cottage cheese My better half liked it very much (I did too, it is very creamy and has an amazing taste and smell).
But deep inside I'm disappointed, I was making everything following the recipe and still failed...

[qdog1955]

You will often see requests to see your make notes---this is so that members can help you diagnose what may have gone wrong. As it is, there is not enough info and would be guessing. Why did you use meso instead of thermo? How long did it ripen? Not familiar with that rennet----but maybe not enough? I see alot of failures with moz. on here, so you are not alone.
Qdog

[sashap]

Hi Qdog and thanks for the reply.
I will provide every info needed, I just don't know which is relevant and which is not...

Why did you use meso instead of thermo?

Well, the answer is very simple: thermo cultures are not available here... I got this mesophilic starter from ebay with a huge shipping cost, my goal is to create a blue cheese. But first I wanted to try it in action.

After adding the culture, I left the milk to ripen for 70 minutes, mantaining 90F (32C), then added rennet. It started to coagulate after approx. 2 hours after adding the rennet and the process was very very slow.

Decided to cut it after 4-5 hours or so, left it for 20 minutes to sit, then ladled the curds in the colander. At this point the curds seemed over-ripened. Of course I could be wrong, but the curds and the whey had a sour taste and it didn't hold together.

Next time I will try to use more rennet. Thanks for the suggestion. In the instructions the dosage is 3-5 drops for 1 liter (13-22 drops for 1 gallon).
I'm concerned about the lack of coagulation after two hours, maybe I should leave the milk for more time before adding the rennet?

Thanks for your time.

Alex.

[qdog1955]

 Here's the thing----some cultures have really slow acidification some are pretty fast---some start slow and then really drop fast----so not knowing what culture you're using, I can't begin to guess-----I use a ph meter because I got tired of guessing. Caldwell recipes are usually good to go---so follow it as close as you can. After ripening your ph should have dropped some, add your rennet and water mix---you probably need to increase the amount of rennet--- bare in mind the rennet may not be any good or getting old.  The make notes are very important---for you mostly---but anything in those notes might be a clue---from temps, to timing, to ingredients.
Qdog

[awakephd]

I'm not sure if any of this is related to the problem, but ... did you add the rennet directly to the milk, or did you dilute in distilled / chlorine-free water first? Did you stir the rennet in thoroughly for no more than 1 minute, and then leave the curd undisturbed?

I'm wondering also about the 70 minute ripening at 90° with a meso culture -- maybe it got too acidified before adding rennet? Not sure that is possible ...

Did you add any heat after adding the rennet?

[Kern]

My WAGNER (Wild Ass Guess Not Easily Refuted) is that either not enough rennet was used or less it was old and had lost potency.  Rennet is more efficient at lower pH. I don't know where the bottom limit is but I doubt that 70 minutes at 90F will produce enough lactic acid to drop the pH much below 6.3-6.4.

Caldwell has a little test for rennet.  I don't have the book in front of me but if memory serves the test uses about a teaspoon of rennet in a pint of 90F milk stirred in real fast.  If the rennet is viable coagulation should occur in about 60 seconds.  Anything less indicates weak rennet.

[sashap]

Thanks guys for the constructive discussion.

I'm not sure if any of this is related to the problem, but ... did you add the rennet directly to the milk, or did you dilute in distilled / chlorine-free water first? Did you stir the rennet in thoroughly for no more than 1 minute, and then leave the curd undisturbed?
Did you add any heat after adding the rennet?

Yes, I diluted the rennet in 1/4 cup of water and distributed it evenly on the surface. Then stirred thoroughly for about a minute with up and down motions.
The temperature was 90F from the start to the finish, without raises or drops (it's very hot here, even without the water bath the milk stays at 90F )

The rennet is fresh, I used it the day after with the citric acid and it worked like a charm... I keep it in the fridge at ~10C, exactly as the instructed by the manufacturer.

It seems that I need to repeat the experiment, but with pH strips on hand. I can't get a meter because it's too expensive for a hobby, but narrow range pH strips should do it.

Caldwell has a little test for rennet.  I don't have the book in front of me but if memory serves the test uses about a teaspoon of rennet in a pint of 90F milk stirred in real fast.  If the rennet is viable coagulation should occur in about 60 seconds.  Anything less indicates weak rennet.

Yes, I read about that, will search it in the book and test the rennet anyway.

Thank you!
Alex.

[Gregore]

Based on the rennet being good   A way out there idea comes to mind.


What if the milk was not as fresh as  you had hoped it might be  so the ph was already lower than optimal
( maybe 6.2 or so )  then you added culture that lowered the ph further ,  if it made it below 5 .7  or even less the rennet will have  a harder time  working at these acid levels  for the amount added ,  it seems unlikely..... But it does fit well with the sour curd  in 4 to 5 hrs  which is unlikely with 6.7 ph milk .

[sashap]

What if the milk was not as fresh as  you had hoped

Good point, I took for granted that the milk is fresh, but it could be as you say.

[awakephd]

By the way, I meant to add in my earlier post -- can you get yoghurt? Yoghurt is made with thermophilic bacteria, so it can be used as a thermo starter. You will need to make sure that it says it has "active bacterial cultures" and if at all possible, get some without additives (such as carrageenen or other thickeners). And of course, use plain yoghurt, not sweetened or flavored.

[sashap]

Hi Andy.

The yogurt was completely absent from our market until now, recently I've seen some Greek yogurt (it tastes AMAZING!). It has only milk and bacteria, nothing more. But it isn't specified whether it is active or not, I'll try it, thanks for the suggestion. But I suppose that I need to test the pH somehow, to know when it drops and rennet can be added. I'll wait for my pH strips to be delivered before my next attempt, to make everything right.

Thanks,
Alex.

[awakephd]

I would say the chances are very good that the cultures are active in the yoghurt. As for the pH -- if it weren't for the odd problem you had with this cheese before, I would have said not to worry about the pH drop before adding rennet; just go by the ripening time in the recipe. Normally I would only be careful about the pH when it comes to the time to start stretching the mozzarella. But since we're trying to sort out what went wrong, and trying to eliminate too much acid at the start, I fully understand waiting for some way to test the pH at the beginning and as it is ripening!