What causes pH to drop quickly during a make? Is it that I'm adding too much culture? Or am I doing something else wrong?
Example:
For my most recent make, a Gouda (
Pav's recipe) the initial
pH of the milk was 6.56. I added 3.5 oz of liquid from boiled mustard seeds. I didn't measure the pH of the liquid.
A little more than an hour later I hit 87.9 degrees (oops, was targeting 86).
pH measured 6.40 already, and that was before I added any culture.
I added 12 oz of primer culture made from equal amounts of MM100 + Flora Danica. pH of culture was 4.37.
Waited 10 minutes, then added CaCl2 and rennet, floc point was 10 minutes, multiplier was 3, so I waited total of 30 minutes, tested for clean break, it was, so I cut the curds. At the end of cutting curds,
pH was 6.31, temp 87.4.
Let heal for 5 minutes, then stirred for 10 minutes, temp was now 86.5 degrees,
pH was 6.26. Falling like a stone.
Removed whey and added 130+ degree water in three stages over 18 minutes. Temp was 99.8, so I heated it to 101 degrees.
pH was 6.23.
Let curds settle 5 minutes, drained briefly and mixed in mustard seeds, packed into mold and pressed under whey with 5 lbs weight for 15 minutes. Removed from whey, flipped and redressed and pressed 6 lbs for 20 minutes. After 20 minutes,
pH of pressed out whey was 5.91.
Flipped and redressed, increased weight to 12 pounds, pressed 30 minutes,
pH was 5.71.
Flipped and redressed, increased weight to 25 pounds,
pH 5.55. I should have stopped pressing at this point based on 5.6 pH target in Pav's recipe, but I'd only an hour and 5 minutes of pressing so far counting the 15 minutes under whey, so I was concerned that the cheese might fall apart. Quite a bit of whey was still coming out of the cheese. I decided to press onward.
I pressed for an hour and flipped,
pH of the whey was now 5.39.
Flip and press two hours -
final pH of the small amount of whey was 5.09, whey below target!
So needless to say, I'm concerned this cheese won't be very good. But what I'd like to know is how to slow down the pH drop during the make. By the whey, the room temperature throughout the make was between 73 and 75 degrees.