Author Topic: PH in cheddar making.  (Read 8080 times)

Offline FarmerJD

  • Old Cheese
  • *****
  • Location: Alabama
  • Posts: 837
  • Cheeses: 34
Re: PH in cheddar making.
« Reply #15 on: November 17, 2009, 07:07:08 AM »
I checked the ph this morning after overnight pressing and it was 4.8. What is the correct target at this point?


Guests, join the CheeseForum.org community to remove this ad.


Offline Sailor Con Queso

  • Old Cheese
  • *****
  • Location: Kentucky
  • Posts: 2,521
  • Cheeses: 125
    • Boone Creek Creamery
Re: PH in cheddar making.
« Reply #16 on: November 17, 2009, 08:50:15 AM »
I think that's right where you need to be. The pH will actually go UP over the next few weeks and months. That's why aging is important.
A moldy Stilton is a thing of beauty. Yes, you eat the rind. - Ed
www.boonecreekcreamery.com

Offline linuxboy

  • Old Cheese
  • *****
  • Location: Ukiah, CA
  • Posts: 3,986
  • Cheeses: 198
  • www.wacheese.com
    • Washington Cheese Guild
Re: PH in cheddar making.
« Reply #17 on: November 17, 2009, 11:21:17 AM »
Farmer, Sailor is right I think. Post press you should be in the 4.9-5.1 range, with 5.0 being about ideal. You did everything right in trying to hurry up and mill/salt as soon as possible. One other trick you could have used is to raise the temp to 105 and try to do that slightly faster. At that temp, the bacteria become less active and produce less acid. I think the cheese will still be very edible. Did the curds knit together well during cheddaring? And did the milled pieces come together ok in the press? If they did, your texture should be ok.
« Last Edit: May 26, 2010, 01:08:36 PM by linuxboy »
Taking an extended leave (until 2015) from the forums to build out my farm and dairy. Please e-mail or PM if you need anything.

Offline Wayne Harris

  • Wine and Cheesemaker
  • Old Cheese
  • *****
  • Location: Cleveland, Ohio
  • Posts: 1,938
  • Cheeses: 53
  • Wayne Harris
Re: PH in cheddar making.
« Reply #18 on: November 17, 2009, 11:58:00 AM »
How does it get less acidic?
Wayne A. Harris - in vino veritas

Offline FarmerJD

  • Old Cheese
  • *****
  • Location: Alabama
  • Posts: 837
  • Cheeses: 34
Re: PH in cheddar making.
« Reply #19 on: November 17, 2009, 12:09:57 PM »
Wayne I think he means the rate of 'acidity increase' slows; this means that it will stay at whatever it is longer. This is my assumption.

Thanks sailor and linuxboy. I weighed the option of raising the temp higher but my heater will only heat this much milk up at a certain rate and it isn't fast. i thought about adding hot water to the heating tank to speed it up also but just opted for a shorter time before draining. So if I had raised the temp to 104 and held it there for the remaining 45-60 min, it would have slowed the acidity drop while the curd was cooking for that final 45 min, right? So for future reference if my ph is pushing 6.1-6.2 at the end of raising the temp to 102, it is probably a good idea to go on to 104 and hold.
i also thought that the salt would slow the ph drop but it didn't seem to. Was I mistaken in this belief?
Also for future reference, when I am cheddaring, I always need to stop when the ph is 5.3-5.4, right? This is one of those points where the clock is not as important as the ph, I guess unlike the cooking process where both are equally important. (please correct if wrong here)
How does the pressing affect ph or does it? I know the ph is still dropping but I mean does the pressure it is under accelerate or decelerate this or neither? Is there a point when pressing where you see the ph is 4.8 and you stop the pressing and refrigerate or do you just "press on"?

The cheese knitted very well at pressing and the curds made a solid mass very quickly when drained, quicker than usual I think.

Sorry so many questions but this ph meter is really generating a lot of curiousity. :)


Guests, join the CheeseForum.org community to remove this ad.


Offline linuxboy

  • Old Cheese
  • *****
  • Location: Ukiah, CA
  • Posts: 3,986
  • Cheeses: 198
  • www.wacheese.com
    • Washington Cheese Guild
Re: PH in cheddar making.
« Reply #20 on: November 17, 2009, 01:02:35 PM »
Yes, that's what I meant. If you look at the rate of acid production at the various temps, for most mesophilic strains, the upper limit of what the bacteria tolerate is 105 degrees. But keep in mind it doesn't stop the bacteria, just slows them down a little. If you used too much starter to begin with, it will not make a huge difference... might buy you an extra 10-15 mins of time.

Farmer, if you had raised it to 104, it would not have made a dramatic difference. In your case, you were fighting time. Bacteria and yeast have these peak periods where they are eating and gorging themselves and multiplying as quickly as possible. Because you gave them an extra half hour at a very comfy temperature, they really went crazy and multiplied. Effectively, it's similar to using 1.5x-2x the normal starter amount, especially if you used a buttermilk or active mother culture. I would say raising the temp is a helpful tool if you are trying to buy a little more time, just as you said if you're at 6.1 and the curds aren't quite there yet and are too moist.

With regards to the salt, it actually does slow down the pH. Did you plot pH drop over time? For example, from culture to whey drain is something like 45 minutes for a .4 drop in pH. This rate of change does decrease slightly after salting. But it's not drastic. At least that's been my experience.

Yes, you must mill at 5.4. If you get to 5.3 it's not terrible. You can also mill at closer to 5.5. You're looking for the right texture at milling. The cheese slabs should be solid, flexible, and if you pull on the end, you should be able to pull a string out, or at least a piece that doesn't crumble.

By the time you press, there's not much you can do about pH. You could slow it down a little by cold crashing the press, but then the curds won't knit. At press time, the game is basically over and now it's time to focus on brining (if relevant), drying, affinage, molds, etc. Any remaining lactose will be eaten right away in 12 hours or slower over the next 24 hours if the room is cool. Outcome in the final cheese is about the same. To put it more plainly, the cheese will do what it will do, and let it do its thing. Press so the curds knit.

This cheese should be fine if it knitted well. A lower pH at draining does help a little with knitting (less calcium phosphate in curds means more protein-protein interaction).
Taking an extended leave (until 2015) from the forums to build out my farm and dairy. Please e-mail or PM if you need anything.

Offline linuxboy

  • Old Cheese
  • *****
  • Location: Ukiah, CA
  • Posts: 3,986
  • Cheeses: 198
  • www.wacheese.com
    • Washington Cheese Guild
Re: PH in cheddar making.
« Reply #21 on: November 17, 2009, 01:09:52 PM »
Oh Wayne, I just realized you were asking how a cheese pH increases with aging. It's because of the protein breakdown and the production of all sorts of compounds. Some of them are basic and bind up with the available acid in the cheese. This takes many months, however, unless you're talking about a bloomy rind cheese. In a bloomy rind cheese like a cam, the mold actually eats the lactate acid and releases proteolytic compounds. As time passes, the lactate moves from the inside of the cheese to the outside and keeps feeding the mold, which causes liquification inside the cheese. That's why cams and bries turn gooey, and why their pH is higher. That and a byproduct of proteolysis can be ammonia, which is basic.

Here's one illustration

http://www.ontariocheese.org/images/microbiology_ph.jpg
« Last Edit: November 17, 2009, 01:20:31 PM by linuxboy »
Taking an extended leave (until 2015) from the forums to build out my farm and dairy. Please e-mail or PM if you need anything.

Offline Wayne Harris

  • Wine and Cheesemaker
  • Old Cheese
  • *****
  • Location: Cleveland, Ohio
  • Posts: 1,938
  • Cheeses: 53
  • Wayne Harris
Re: PH in cheddar making.
« Reply #22 on: November 17, 2009, 01:12:21 PM »
I guess I just thought the journey down the pH path was one-way, at least through pressing.
Wayne A. Harris - in vino veritas

Offline linuxboy

  • Old Cheese
  • *****
  • Location: Ukiah, CA
  • Posts: 3,986
  • Cheeses: 198
  • www.wacheese.com
    • Washington Cheese Guild
Re: PH in cheddar making.
« Reply #23 on: November 17, 2009, 01:17:35 PM »
I guess I just thought the journey down the pH path was one-way, at least through pressing.

It is, but not as a linear function. The instantaneous rate can be manipulated for short periods of time to deviate from an expected outcome. For example, if you suddenly took the curds and whey and chilled them to 35 degrees. That would influence the rate of decrease.
Taking an extended leave (until 2015) from the forums to build out my farm and dairy. Please e-mail or PM if you need anything.

Offline FarmerJD

  • Old Cheese
  • *****
  • Location: Alabama
  • Posts: 837
  • Cheeses: 34
Re: PH in cheddar making.
« Reply #24 on: November 17, 2009, 01:42:17 PM »
After this thread i want to go make another batch before I forget everything. I bought a meso 11 powder pack and used it to make a mother culture the morning of my cheddar making. I think next time I will decrease the time of culturing to about 40 min. and watch for the ph drop of .2; which ever comes first. My brain is hurting after all this learning. :)


Guests, join the CheeseForum.org community to remove this ad.


Offline Wayne Harris

  • Wine and Cheesemaker
  • Old Cheese
  • *****
  • Location: Cleveland, Ohio
  • Posts: 1,938
  • Cheeses: 53
  • Wayne Harris
Re: PH in cheddar making.
« Reply #25 on: November 17, 2009, 01:44:35 PM »
It is, but not as a linear function. The instantaneous rate can be manipulated for short periods of time to deviate from an expected outcome. For example, if you suddenly took the curds and whey and chilled them to 35 degrees. That would influence the rate of decrease.

Ok,  that jibes with my understanding.  Thank you.
Wayne A. Harris - in vino veritas

Offline Sailor Con Queso

  • Old Cheese
  • *****
  • Location: Kentucky
  • Posts: 2,521
  • Cheeses: 125
    • Boone Creek Creamery
Re: PH in cheddar making.
« Reply #26 on: November 17, 2009, 02:25:44 PM »
Farmer - making more cheese is always good when your "brain is hurting". ;)

Obviously, time in any cheese recipe is not to be trusted. Smith, Carroll, Morris, Dixon... They all use different times for the same cheese. These times are based on their experiences and are not wrong per se under THEIR conditions.

The flocculation method eliminates the time variable and takes the guess work out of curd set. While pH readings eliminate most of the time variable for ripening, draining, etc. If I have reliable pH targets, I usually ignore the clock and wait for the proper targets. As Farmer has seen, the pH can change very quickly so a simple time based make can be way off.

Like baking a cake really. The recipe says cook at 325F for 50 minutes OR until a knife comes out clean. They always put that disclaimer in there. ;D If you cook it for the full 50 minutes, it may turn out overcooked and dry.
A moldy Stilton is a thing of beauty. Yes, you eat the rind. - Ed
www.boonecreekcreamery.com

Offline Wayne Harris

  • Wine and Cheesemaker
  • Old Cheese
  • *****
  • Location: Cleveland, Ohio
  • Posts: 1,938
  • Cheeses: 53
  • Wayne Harris
Re: PH in cheddar making.
« Reply #27 on: November 17, 2009, 02:39:45 PM »
I always use this analogy:
One can stop at a stopsign that you know is a exactly 1 mile away, by driving 60mph for exactly 1 min.
-or-
you can look out the winshield.

Which would you rather do?

Wayne A. Harris - in vino veritas

Offline Sailor Con Queso

  • Old Cheese
  • *****
  • Location: Kentucky
  • Posts: 2,521
  • Cheeses: 125
    • Boone Creek Creamery
Re: PH in cheddar making.
« Reply #28 on: November 17, 2009, 02:40:37 PM »
Because the pH does eventually go up as proteins break down, aging longer than usual might help "rescue" an otherwise acidic cheese. ?? There can be a HUGE difference between a 60 day and a 90 day cheese because that's when all the enzyme activity really starts kicking in.

Makes you appreciate how old time cheesemakers intuitively knew what was going on with their cheese during a make. Of course doctors actually used to taste urine to detect diabetes. Thank goodness for pH meters. ::)
A moldy Stilton is a thing of beauty. Yes, you eat the rind. - Ed
www.boonecreekcreamery.com

Offline FarmerJD

  • Old Cheese
  • *****
  • Location: Alabama
  • Posts: 837
  • Cheeses: 34
Re: PH in cheddar making.
« Reply #29 on: November 17, 2009, 05:06:04 PM »
I agree with the points about ph being the primary indicator of what is happening but I thought that other things were also happening when you are cooking besides acidification, and these other things also must have time to happen. (Again, could be very wrong) Is the development of the curd exclusively related to ph or at least if ph is right - curd will always be right? You could have a ph target and yet the curd not be right yet, correct? This is what I am trying to understand. If I heat to 102 and the ph is already 6.1, I cannot just skip the period of holding at 102 without an effect on the outcome, so even though ph is a primary indicator I can't just ignore the timing completely in some parts of the process.

Sailor your example of the cake implies that the knife is measuring the only important variable that determines when to take the cake out: Dryness. If the dryness is right there is no other reason to leave it in there. Can we say the same for ph targets at every part of the process?

Now I really have a headache. I just read over my post and it sounds like I need a sedative. Ignore if it doesn't make sense. ???  ;D