The consistency of gum

Sandy,
Dick would have to verify this, but I think what you're up against is
the fact that percent solution doesn't have much useful meaning for gum,
and that's why specific gravity is the standard for getting it right,
rather than the percent solution.

What's important for gum is that it's the right consistency (I won't say
viscosity, since Gordon pointed out that specific gravity and viscosity
aren't correlated). How the gum spreads is the thing that's important,
and since gums are so variable across year and source and grade and
type, it probably takes a different amount of the actual gum in each
case to reach the right consistency (but I think those differences are
smaller than you do). So if two gums have the same percent solution but
are different in specific gravity, then one of them will work and one
won't. So comparisons based on percent solution wouldn't be very
meaningful. This is what I meant when I said that you're demanding an
exactitude of gum that it can't deliver.

It's like trying to say how much flour is in a loaf of bread. The right
amount is the amount that makes the dough right, and it will be
different from day to day depending on the humidity in the air and so
forth. The experienced baker doesn't try to measure the flour precisely
but just adds the right amount. When you've baked a lot of bread, you
know just exactly how the dough feels when it's right.

After listening to the Melvin group talking about how gum behaves, about
the difficulty of coating smoothly with a brush, etc etc, I thought that
that Bostick & Sullivan gum must be hugely different than the gum I'm
used to, because I didn't recognize any of these qualities they were
describing.

But now I'm looking at six gums, one of which is the Bostick & Sullivan,
and they all behave about the same; they all brush smoothly, their
consistency is very, well, consistent, as is their behavior. (Yes, there
are differences, but the differences are subtle, not dramatic.) So I'm
not included to credit the idea that there are huge differences between
gums. My 2cents.
Katharine Thayer
Received on Tue Dec 2 10:17:54 2003