Re: formula needed: Gum Arabic from powder

From: Joe Smigiel <jsmigiel@kvcc.edu>
Subject: RE: formula needed: Gum Arabic from powder
Date: Wed, 24 Nov 2004 08:57:23 -0500

> I would think a bit of Listerine or similar mouthwash would work-the
> active ingredient is thymol IIRC.

I think Listerine contained 0.064% thymol. It would require 10+ milliliters
of this stuff per gram of soluble solids in the solution for optimal results,
and I don't know what the effects of other stuff in Listerine might have.

I'd just call Kremer Pigmente (1-800-995-5501, KremerInc@aol.com) and
order 78740 Preventol ON Extra (sodium 2-phenylphenolate) for $7 or so
and be done with it for good. It's a very good all round bactericide
and fungicide used in many places, including silver gelatin emulsions.

Adding an acid to gum solution may help a bit, especially if combined
with refrigeration but it can only slow bacterial growth and not
suppress the growth or kill them. This may be ok as a short term
preservative for edible stuff, but no good for long term, because
yeast and fungi grow in acid environment, even if refrigerated.
(Usually, bacteria grow faster and their growth limits the shelf
life. If acid is used to slow them down, shelf life is now limited by
yeasts and molds.)

--
Ryuji Suzuki
"People seldom do what they believe in.  They do what is convenient,
then repent." (Bob Dylan, Brownsville Girl, 1986)