I was making a Colby this morning, and had calibrated my pH meter prior to use.  I did a 2 point calibration - to both 7.01 and 4.01.  During the cook, I was monitoring the pH which was steadily dropping.  It reached 6.15 and I was anticipating a 6.0 whereupon I would drain the whey.  However, the next check I did was at 6.26.  This seemed rather odd to me, so I recalibrated to find that the meter had shifted rather dramatically.  After recalibration, I checked the same sample and got a 5.85.  Now is this a somewhat normal phenomenon for a meter to go off so quickly; or does it appear that I may have done something else that affected it this way?  I think I caught it quickly enough that my cheese was not adversely affected; but only time will tell on that.

I don’t think using a PH meter is as easy as we’re lead to believe. I too had problems yesterday. Making an Edam, start PH at 6.4 immediately after calibration, part way through it dropped to 6.3, then almost immediately went back to 6.5?
Until I have time to do more experiments I can’t accept these readings. I think my start PH was too low.

If the prob has not been pre soaked then it will drift. If the probe is older then a year, it is worn out even if its not used. trry the pre soaking (several hours) if that has not rectified it then contact dealer.

I store the meter with the tip in water, so pre-soaking is not an issue.  Guess I’ll monitor it closely for the next couple makes and see what happens.  Its only 3 months old, so I’m fairly confident its not worn out.

Green Cheese Maker - 10 May 2010 12:08 AM

I store the meter with the tip in water, so pre-soaking is not an issue.  Guess I’ll monitor it closely for the next couple makes and see what happens.  Its only 3 months old, so I’m fairly confident its not worn out.

Same here except this is only the second time I’ve used it. Mine is stored with ‘Storage solution’ in the cap, so mine hasn’t dried out either.
Is water a suitable storage medium?

Depends on the water, some tap water is full of cloreen and other corrosive substance. I use 7ph solution, distilled water would be better then tap water, or filtered water.

No, water is no good - in many cases it will damage the electrode. In order of chemically best use either KCl storage solution or pH 7 buffer solution.

I spent some time running lab analysis (PH and TA) at a local winery. I learned that your buffer solutions should be replaced about every 6 months along with the PH meter probe. I use a $50 handheld meter at home for wine and cheesemaking and am finding it inadequate. I just have a hard time trusting the readings even after calibration. As far as the buffer solutions go I would buy the small foil packets instead of the bottles so you can always have fresh solutions to calibrate with. I’ve come to the conclusion that if you really want to be sure of your PH readings you need a decent benchtop model starting at around $300.

Wow, not good news :(

Been away a while, but thinking of making another batch.  Looking at meters, and tried to find the phh7x, but seems to be discontinued.  Has anyone seen this meter:  HANNA HI 98103 Digital Water pH Meter Tester, Checker. Would this be a decent choice?  Now, when storing the probe, do you put it into a bottle of buffer solution or exactly what do you do for storage of the probe?  Thanks for the help.  Kim

My Hanna Checker comes with a rubber probe cover that enables me to keep buffer solution around the probe tip during storage.

The rubber boots still dry out, make sure u wet it the day before.