Thanks for responding. I used Thermophilic 81, 1/8 tsp for a gallon of milk. The milk was not sour to smell or taste but, as I said, it was close to it's use by date. Given that it tasted noticeably acidic I don't think the ph strip was too far off the mark. Maybe I should consider using Kefir...
This was my second try at making cultured Mozzarella, and I mostly followed Caldwell traditional aging recipe. After cutting the curd and slowly bringing temp up, she says to hold at 118 until ph is down to 6.0, might take 60-90 minutes. I checked with ph strip after 60 minutes and I was already...