Using a pH meter and lowest pH to kill botulism
I have a basic canning/pickling question. Many questions really, but just one today.
I understand that the way pickling works is by reducing food pH so botulism and other nasties cannot live in the food. A quick google search gives me pH 4.8 as the lowest that can host botulism. Does this mean that as long as I achieve pH 4.7 or lower, I am save just using BWB canning? or even just refrigeration?
I recently got a pretty accurate pH meter (SPER scientific large display pH pen). I have been using it for garden soil samples, but it can be cleaned well. I am also going to make/buy a buffer solution to increase the accuracy. I was wondering about measuring the pH of the food prior to canning, both for information/curiosity, and for safety reasons. Do any of you measure pH for canning/pickling purposes?
It turns out I do not like really sour pickles, or really acidic tomato sauces, so I would prefer to stay near the 4.7pH range, allowing 0.2 pH for meter accuracy. I also wanted to confirm that 4.7pH is safe enough. Thanks for your comments and answers.
OK, I said just one question but there is a related one. Since both salt and vinegar are used in pickling, and both have a preservation effect. Is there a way to measure the synergistic effect of both salt and vinegar? like if i use enough salt, I can raise the safe pH some?