"The Joneses" > wrote in message
...
>
> 2. Is there a problem with testing at various temperatures from cold
> to over boiling?
> "The paper itself will hold up with cold or hot samples. However,
> if
> temperature affects the pH of the item, you will have results of the
> product's pH at time of testing."
>

I really wish I'd paid better attention in high school chemistry class a
bazillion years ago.

But how does temperature affect pH? I understand that if you boil a
solution some liquid will be vaporized -- is this what they mean? If so, if
you mix water and vinegar to a certain pH level and then boil it until it's
reduced by half, does just the water boil away, leaving you with a much
lower pH? Or does some of the acidity boil away, too?

If it's not the "cooking causes loss of liquid" thing, what is going on?
Does room temperature vinegar have a different pH than refrigerated vinegar
or vinegar warmed to 120 degrees Fahrenheit?

In any case, if the pH varies with temperature, which pH is important -- the
one used when putting the product into the jars or the room temperature at
which the jars will be stored?

Anyway -- thanks loads for posting this Edrena!

Anny