I've tried the ph metres, non of them work well enough to be of any
use, can't even relie on subsequent readings on the same test subject.

Got my money back on them.

It is well known that most tomatoes run at below ph 4.6 and do not
need further acidification, however, it would not hurt to add a small
amount of citric acid to be sure, certainly not the 1 tablespoon to a
pint as suggested one.

Like you I generally add half a teaspoon to 1 lt/qt of whatever I'm
doing.

I also use lemon juice, I also use vinegar in many applications,
knowing that 5% white vinegar runs between ph 2.3 & 2.5 it's easy to
work out.

Anyway I have a number of ph strips arriving shortly so I should get a
better idea.

On Tue, 13 May 2008 22:29:46 -0700 (PDT), jimnginger

>You may wish to purchase a ph meter on line or on eBay that is food
>grade (accurate enough to be of some value). I add no more than a
>teaspoon of citric acid to a quart of tomato products. It has less of
>a taste than lemon juice and is much more effective in bringing down
>ph without altering the taste of the original product. In jams and
>fruit products it may be desirable to use lemon juice because the
>flavor compliments the fruit. If not, tart it up (or lower ph) with
>citric acid or with an acid blend. Regards - Jim in So. Calif.

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