PH convertion from book "wines and cheeses of England)

[Promiseland Farm]

Anyone know how to convert the ph numbers from the book wines and cheeses of England to the readings I'm use to seeing on my litmus paper and Hanna meters. I have a range like from 5.1 to 6.8 when I make cheese and that book is all in decimals... Like .22 and .15

Thanks!!!

[Sailor Con Queso]

.22 or .15 is not a pH reading. Litmus paper is worthless.

[awakephd]

Welcome to the forum!

Litmus paper is certainly a challenge, though there are some members that seem to be able to get useful information that way. I would guess that the numbers you are seeing are for measuring the acid through Titration. Do a search for that on the forum, and you'll find some information on how that relates to pH.

[jmason]

Indeed Welcome to the forum.  Your videos were very helpful to me when I started making cheese.  You'll like it here many knowledgeable artisan cheese makers and generally good folks.  Last I saw your daughter is getting so big. 

Anyway, the numbers you are seeing are "total acid" or titratable acid as a percentage of the total solution.  In wines they are not convertable to pH per se, unless you assume that all acid is tartaric acid (it has to do with the difference between weak acids and strong acids and the different chemistry they have in affecting pH).  There are calculators online or charts that might do an acceptable job of this in wine, more or less.  Cheese might work better since acidity is almost entirely lactic acid, not sure if there are any such charts for cheese.  An online search might yield some conversion tools but they would only be rough approximations since the 2 methods are measuring different things, both acid (or base in the case of pH) but in much different ways.

http://www.eckraus.com/blog/difference-between-ph-and-titratable-acidity-in-wine
http://www.crcv.com.au/resources/Grape%20and%20Wine%20Quality/Workshop%20Notes/Measuring%20TA%20and%20pH.pdf

these two links might help a little, at least to understand the difference, the second one does have a chart but I would use it only as a very rough guideline.

Anyway glad to see you here.

John

[Dibbs]

http://cheeseforum.org/forum/index.php?topic=5816.0