Mozzarella curd became a mess!

[nscheeseguy]

Hi Everyone,

I wish I have found this forum earlier.  I attempted to make mozzarella a few times already, both Citric acid method and culture method. The cheese that is acidified with citric acid  turned out ok but tasteless so that I stopped making it. Now I use both Mesophilic and Thermophilic culture to make it. But the curd always turned to be a mess as shown in the picture below every single time. The curd would stick together in the first few seconds; however, as I start to press it, it became soft and turn into crumbles. Could you anyone here help me to find out what the problem is? Would it a PH problem that most people have encountered? or the water temp is too high? Please help!

Here is my recipe:

Ingredients:
1. 2L store bought homogenized milk
2. 1/8 tsp Mesophilic and 1/10 tsp thermophilic Culture mix
3. 1/16 tsp dry calf rennet

Method:
1. 1. Warm milk to 86f (30c).
2. Sprinkle cultures let them dissolve and then gently stir in using top to bottom stroke for about 20 strokes.
3. Allow milk to ripen at above temperature for one hour.
4. Add rennet to milk and stir in. Maintain above temperature until  the milk coagulate into a firm curd and have a ‘clean break’.
5. Cut curd mass into ¼-1/2 inch pieces using vertical and horizontal slices of the curd mass.
6. While stirring slowly heat the curds in the whey to 102f (39c). Take 45 minutes to reach target temperature. Raise heat slowly about 1-2 degrees every five minutes or so.
7. After reaching target temperature let the curd mass settle to the bottom of your pot and let them rest there for about 30 minutes.
8. Drain off about 1/3 of the volume of the whey and hold the curds in the whey bath for another 20 minutes.
9. Drain the curds in a cheesecloth and let them rest another 3-4 hours at room temperature 78f (25c). Store the slab in the refrigerator overnight and heat and work the curds the next day.
10. From the original slab of curd cut off good size chucks 3/4 inch (2cm) thick and work in the hot water forming them into balls. Maintain the water temperature so it is at the temperature of  (145-165f (64-74c).

[linuxboy]

Wait, are you using DVI cultures? 1 and 1/8 tsp for 2 liters of milk? If so, that's too much.

Your issue here is acid development. Judging by the texture, that cheese has a pH of 4.8 or less. You can't ever go below 5 in mozz. Your curd was done at the end of those 3-4 hours, or earlier. Did you test for stretch at all?

[nscheeseguy]

Sorry, I have made a change on my posting. Yes, I used both DVI cultures. Mesophilic (1/8 tsp) and Thermophilic (1/10 tsp) for 2L milk. Is this too much? I am  trying 1/10 Thermophlic culture for 2L 2% partly-skim milk. See if this is going to work.
I rested and drained the cheese for 3-4 hours and put into refridgerator to further develop the acidity. Before I made the cheese, I tested a couple of chunks, they would soften and break when I stretched it. Does this indicate the curd has developed too much acidity?

The problem is I don't have a PH meter to test the acidity. Maybe this would be my next investment.

[nscheeseguy]

Wait, are you using DVI cultures? 1 and 1/8 tsp for 2 liters of milk? If so, that's too much.

Your issue here is acid development. Judging by the texture, that cheese has a pH of 4.8 or less. You can't ever go below 5 in mozz. Your curd was done at the end of those 3-4 hours, or earlier. Did you test for stretch at all?

I only used 1/10 tsp Thermo culture this time. And work the curd the next day after store it in the fridge overnight. Here is what the curd turned out to be:
Does this still look like PH problem?

[MrsKK]

Is this before or after you heated up the curd?  If after, I don't think you are heating it up for long enough.  It should be smooth and shiny when you are done heating and stretching it.

[nscheeseguy]

Is this before or after you heated up the curd?  If after, I don't think you are heating it up for long enough.  It should be smooth and shiny when you are done heating and stretching it.

This is after heating up the curd. I heat up the curds for about 2-3 minutes. They did not melt or become soft enough instead they became so rubbery. When I stretched them, they broke into pieces. So I had to rub them together to save the curd. Still taste pretty good though
Do I need to heat longer? Or is it still a PH problem?

Thanks a lot!

[linuxboy]

So this time when you heated them they didn't turn into mush? The curd still held together, but now are breaking apart as large pieces, but are coming back when you smoosh them together?

If that's the case, then pH is too high and you didn't use enough starter or you cooked at too low a temp, and the culture didn't have a chance to make enough acid.

That curd looks like it has high (5.8+) pH to me... you can see good bonding, indicating little depredation of calcium phosphate bonds.

What happens when you fry it in a pan? Does it brown or melt? If it brows, definitely too high of a pH.

[nscheeseguy]

So this time when you heated them they didn't turn into mush? The curd still held together, but now are breaking apart as large pieces, but are coming back when you smoosh them together?

If that's the case, then pH is too high and you didn't use enough starter or you cooked at too low a temp, and the culture didn't have a chance to make enough acid.

That curd looks like it has high (5.8+) pH to me... you can see good bonding, indicating little depredation of calcium phosphate bonds.

What happens when you fry it in a pan? Does it brown or melt? If it brows, definitely too high of a pH.

I just tried to fry some of the chunks. They did not completely melt but became more shinny than I worked the curds this afternoon. The texure is gooey like gum. I have attached another picture below after frying. PH is still high?

[linuxboy]

Yep, that looks close to what an emmethaler looks like when you nuke the fresh curd in the oven. You need to wait and let the acid keep building, and breaking down those bonds. Eventually it will be at the right pH. Put it at a high temp, 110 F, because this is thermo culture, and test it every 30 mins until you get a stretch. It did melt a little, so I would guess, you're just at or under 5.8.

See how in your early first pic, the curd is mush? Lots of little tiny bits, all not holding to each other? That's too much acid. And in the latest pic, especially of the several melted chunks, how the melted curd is all together, just rubbery and gummy and not stretchy? That's not enough acid (for mozz).

[making mozzerella]

So when there is too much acid (mush) can you do anything at that point to get it back from the dead?
and when there is not enough acid (chunky) again, can anything be done?
And is there a cheese ph testing device available?  If so, where do you get one, how does it work, and at which point in the cycle do you use it?
Thanks
(Having the same type of problems)

[linuxboy]

Too much acid is tough to recover from. Debi has said she has nuked and kneaded a bunch of times, but I suspect that the acid levels were ok for those cheeses. Shattered curd can still make a mozz, but overacidified curd cannot. Just chemically impossible.

Too little acid is easier, just heat the curd to the right meso or thermo temp and wait and test for stretch, then nuke or cut and dump in hot water.

To test cheese pH, use a pH meter. Many, many discussions here in the past about meters, with recommendations and usage guidelines.

[DeejayDebi]

Wish I could tell you about the acidity on the nuked cheese but I never used a pH meter on them just grabbed my coat and ran! 

I can say that a salvaged a few that were a day or two old.

[nscheeseguy]

Thanks for all the replies. They are really helpful.

[nilo_669]

Acidic curds