This thing is awesome. Dip it in the milk or whey, and about 10 seconds later, Blammo! you've got a pH reading! (okay, there isn't actually any explosion, unless you yell "Blammo!" yourself, which I highly recommend).
It's as easy as using a thermometer (and actually includes a thermometer, since pH readings done in this manner must be temperature-calibrated).
Of course, without knowing exactly what pH we're supposed to hit and when, this cool little device won't actually be much help. None of my recipe books reference pH numbers -- just times and temperatures.
I've been sifting through my copy of Paul Kindstedt's American Farmstead Cheese, which is by far the most technical book in my library. He discusses pH in depth -- but since the book doesn't include any specific recipes, that only helps so much.
I did find a table on page 155 where he indicates "optimum" pH -- with some timing -- for making Cheddar. Already it's been a bit of a help: Heating the curds (bringing them up from 86°F to 100°F) went slower than I would have liked, but keeping an eye on the pH still let me know we were making progress.
As the pH slowly worked its way down, I decided to drain the curds at 6.15 -- based on Kindstedt's table. This took more than an hour longer than Ricki's recipe, but less time than indicated in the table.
As I write this, the curds are cheddaring comfortably in the pot. After only 15 minutes, on the first flip, the pH was down to 5.80. If all goes according to plan, at the end of the requisite two hours we'll be at exactly 5.35, and then we'll mill the curds (translation: break them into small cubes), and proceed with the next steps.
If we hit 5.35 a little early, I might actually decide to stop cooking and mill them sooner than Ricki calls for.
I'm excited to start using the pH tester every time -- building my own reference library -- and hopefully with a bit of diligence I'll be able to solve my texture problems once and for all.
Do you have any experience pH readings? Please post in the comments with any questions and/or advice!