late acid production

[jaghoss]

Hey, I'm hoping to get a little better insight into late acid development. I seem to be fighting it with some of my cheeses. PH levels are good- until about 15-24 hours after pressing, then they plummet. The cheese shows signs of excess moisture, and develops an increasingly bitter taste. I don't see this with ever batch, and no more-so with any certain type of cheese. What normally causes it? How do I best prevent it?   

[Kern]

If you finish pressing a cheese at a pH of 5.3 and get it into 55F saturated brine immediately and get the entire brine/cheese container in a 55F cave it is very unlikely that the pH will drop much below 5.0-5.1 during brining and will likely bounce back to 5.2-5.3 after several days of drying.  This is pretty much inviolate.  The combination of both the 55F temperature along with the salt level rising in the cheese effectively kills the lactic bacteria.  (Dead bacteria don't make "late acid" )  It is important that the brine be saturated with salt.  A good check on this is to have salt crystals at the bottom of the brine storage container.  Be sure to brine for the proper amount of time - usually 3-4 hours per pound for a pressed cheese with a diameter to height ratio of about 2:1. 

If all the above is present and the cheese was properly pressed (knit curd, very slight discharge of clear liquid under pressure) and you get readings down in the high fours or lower then you are not reading the pH of the paste.  Either your meter needs calibrating, is broken, or clogged, greasy or whatever.  So, I would not assume you have a problem and certainly would not worry about it.  If this troubles you then you should get a trier,  pull a sample and check the pH of the actual curd rather than the embryonic rind.