Ph meters....again...this time concerning readings

[Likesspace]

Hi guys.
I emailed Egon at Danlac and he sent me a couple of different recipes.
My problem is that instead of the recipes listing target Ph levels it lists acidity level expressed in percentages.
My question is if there is any correlation between % acidity and Ph.

For instance the end point of Danlac's  Cheddar recipe is: 0.65% - .075% acidity.
In the recipe I used over the weekend the end point was 5.3 - 5.4 Ph.

I honestly don't understand how to use the recipes Egon sent, since percent of acidity INCREASES over the course of the recipe and Ph DECREASES throughout the recipe.
Now I'm just flat out confused.
If anyone can offer any advice, I'd love to hear it.

Dave

[wharris]

I think that Acid concentration is the actual measurement we are interested in.  It is what we are trying to measure.   pH is an indicator of acidity. pH below 7 are acids, while above, they are considered bases. Here is a scale:


But If you can measure the acidity directly,  that's even better.

Here is how pH and acidity might be used togethe:
pH can be used to determine acidity.  Theoretically, you can measure the acid concentration of an unknown acid (like whey, or wine), by adding a base (opposite of acid) until equilibrium is reached. That is, the resulting mix is neither acidic, nor base. Its neutral, with a pH 7.00. If you know how much of the known concentration of base added to the sample, you can calculate the acid level of the sample.

This is a classic acid titration test.

There are very elegant examples of how this is done in winemaking,  i will look them up.

As a wine maker i use an acid titration kit, where i add a base Sodium Hydroxide (NAOH-) to a sample that has a reactant in it. The reactant will change color at equilibrium.

[Likesspace]

Wayne,
I read about this earlier this evening but I have to admit that it's a little over my head. In wine making I used the dip strips.
I was hoping there would be a "curve" of sorts where % of acidity was listed on the bottom and Ph listed on left side. Then all I would have needed to do was draw a line up from the % of acidity to the the intersection of the curve and read the Ph level.
I'm used to reading pump performance curves so this would have been so easy to follow, although I realized it was a long shot. :-)
Thanks for the information though.
I think one thing I will try is using my meter throughout every process and keeping very good records.
That way I can try to figure out where mistakes might have been made that produced a less than desirable cheese.
Tom (Fine Wino) suggested a book called "Artisan Cheese Making" that I want to give a try. I guess it is filled with a lot of informatoin that will help with this sort of trial by error method.
Thanks again, Wayne.
If nothing else, I will buy a test kit and give it a go.

Dave

[wharris]

Give it time Dave. 
I would not sweat this yet.
Can be alot to absorb. All I can say is thank goodness most recipes don't call for specific acid concentrations.

pH will do nicely.
-or-
"add starter, wait 45 min" will also do nicely

[Likesspace]

Yeah, I know Wayne....I really get obsessive about doing things as well as possible.
Each year my cheesemaking seems to get a little better (due to reading, discussing and practicing) so I need to just take a deep breath and allow it to happen.
Btw....I just realized that I mis-quoted Tom in my previous post. The book recommended is: American Farmstead Cheese, not Artisan Cheese Making.
Sorry for any confusion.

Dave

[Cartierusm]

Dave I actually wrote something to you in another thread telling you, you should be checking TA levels. Here's the post. Why don't you give me a call tomorrow and I'll explain it, it's very easy and the kits are dirty cheap.

https://cheeseforum.org/forum/index.php/topic,1077.15.html

When I first read American Farmstead Cheese I thought it was a horrible book as it talks a lot about PH but not the practical application so it's uselesss, but now that I know a lot more about what's going on in cheese I'll reread it, right now it's sitting on my desk starring at me.

[Likesspace]

Carter...
I just saw this post.
I will give you a call once I take the next step and get a TA kit.
Right now I have found several different recipes that give Ph readings throughout the process and I would like to get more of a feel of this method before changing to something else.
Right now the Ph meter just seems so much more simple to me than working with chemicals. I'm sure after doing it a few times it would be a no brainer, much like testing the water in our pool.
I've also decided that your idea of logging Ph readings over an entire "make" is a good one.
It makes sense that even without target Ph readings in a recipe, if we will log our readings over the course of a cheese make, we are making our own benchmarks in the process.
If nothing else, this will make for a great troubleshooting guide if and when a cheese doesn't turn out as expected.
If on the other hand, the cheese DOES turn out as we had hoped, then we have a record of the Ph readings we need at every step.
Good thinking, and thanks.

Dave