Hi Andy. No, I don't have a pH meter. I do have some pH paper but I find it of limited value and seldom use it. The supplier of my cultures (cheesemaking.com.au) has confirmed that high acidity is the problem and cites the pale colour in the middle of the cheese as further evidence of this.This, together with the temperature and the salting certainly gives me some things to think about if I decide to attempt one of these again.Many thanks for the information.