Alfred University's Summer Institute
Lisa Boffa's Home Page
Murphy's Law
Scitech's Science for kids home page
Science Jokes
Strawberry Pop-Tart Blow-Torches
Joe Keane saved some posts from the late Larry Lippman. They are
about gelatin, thickeners, and K-Y jelly. "I think they
are characteristic of his style. I wish I had saved more" said Joe.
**********************************************************
From: (Larry Lippman)
Subject: Dead Horse in Gelatin (was Re: Protein in Shampoo, What Is It ???)
Summary: All gelatin is derived from animal products
Date: 2 Dec 89 05:27:37 GMT
In article <708@odin.cs.hw.ac.uk>, raza@cs.hw.ac.uk (Z. Raza Hussain) writes:
in the formation of gelatin. Remember that the next time you eat a gelatin
dessert, you are probably eating a dead horse. Really. :-)
Isn't it true that gelatin (or is it gelatine, any difference?) is
made out of synthetics or something artificial nowadays ???
Nope. There are four generally recognized grades of gelatin (edible,
technical, photographic and pharmaceutical), ALL of which are extracted from
animal products, most commonly skin, bones and "fleshings".
Manufacture of gelatin is a multi-stage process, briefly described
as follows in an example which uses bones as the raw material:
1. Bones are are first degreased by heating with steam or through the
use of petroleum naptha as a solvent.
2. The degreased bones are then crushed.
3. The bones are then addded to a tank containing water and lime, and
are heated to about 70 deg C for an hour or so.
4. The bones are then treated with cold, dilute hydrochloric acid
which dissolves calcium carbonate, calcium phophate and other
mineral matter, thereby leaving the organic matter. This material
is now called ossein.
5. The ossein is then soaked in vats with calcium hydroxide, which
removes soluble proteins, such as mucin and albumin.
6. The resultant material is then washed with slighly acidulated
water to adjust the pH for optimum hydrolysis.
7. The resultant material is then hydrolized with dilute acid
solution to form gelatin in a repeated series of extractions
beginning at about 60 deg C and ending at about 100 deg C.
8. The gelatin may be bleached with hydrogen peroxide or sulfur
dioxide during these extraction stages.
9. The resultant gelatin is then dried and ground into a fine powder.
Ain't no other practicable way to make gelatin. While my original
remark about the dead horse was intended as humor, it is far more truth than
fiction. From what I observed, the two rendering plants I have seen over
the years weren't too careful about segregating their, uh, raw material.
As one crusty plant engineer said to me, "Bones is bones". :-)
Larry Lippman @ Recognition Research Corp. - Uniquex Corp. - Viatran Corp
.
**************************************************************************
From: (Larry Lippman)
Subject: Looking for thick liquids
Summary: Hydrophilic colloids & DIY fast food restaurant milk shakes...
Date: 27 Dec 90 04:05:23 GMT
In article <1990Dec26.214729.2334@ultra.com>, bob@ultra.com (Bob Beach) writes:
I am looking for a means of creating a very thick liquid. Ideally it
should be clear, non toxic, not corrosive, and reasonably cheap to make.
I would like to be able to create varying degrees of "thickness".
You did not state the application, so I can't recommend any one
agent over another, but I will give you some general suggestions based
upon thickening agents used as food additives. Such thickening agents
will obviously meet the conditions of being non-toxic and non-corrosive.
Consider using the following, all of which form hydrophilic colloids:
1. Agar - a polysaccharide mixture of agarose and agaropectin derived
from algae
2. Arabic gum - carbohydrate polymer derived from acacia plants
3. Bentonite - a colloidal clay largely comprised of aluminum silicate;
this is indeed an FDA-approved food additive - scary, huh? :-)
4. Carrageenan - a polysaccharide derived from seaweed
5. Methylcellulose and carboxymethylcellulose - cellulose derivatives
6. Polyethylene glycol (PEG) - a relatively inert condensation polymer
of ethylene glycol
7. Xanthan gum - a synthetic carbohydrate polymer, similar to natural
gums
There are various other agents, including numerous variations of
the above substances (e.g., ammonium alginate, calcium alginate, sodium
alginate, etc.).
The hydrophilic colloidal properties of some of the above substances
are amazing. Some years ago, I used to do a "party trick" that involved a
parody of a fast food restaurant milk shake. I would take 12 ounces of
water, add a tablespoon of milk, a tablespoon of chocolate syrup and a
tablespoon of xanthan gum. Mixed in a blender for a few minutes, the
result was virtually indistinguishable from a typical McShake. So much
for the "milk" in "milk shake"... :-)
Larry Lippman @ Recognition Research Corp. "Have you hugged your cat today?"
**************************************************************************
From: (Larry Lippman)
Subject: Looking for thick liquids
Summary: Everything you ever wanted to know about chemistry of K-Y Jelly :-)
Date: 28 Dec 90 04:59:08 GMT
In article <1990Dec27.150503.13692@kodak.kodak.com>, ornitz@kodak.kodak.com (Barry Ornitz) writes:
One simple material would be sodium carboxymethyl cellulose.
BTW, an already mixed solution of CMC in water is sold as KY Jelly.
K-Y Jelly also contains sodium alginate and a small quantity of
EDTA. The EDTA is used to sequester calcium ion impurities in the sodium
alginate, with the effect of such calcium ions being undesirable high
viscosity when the product is at lower temperatures. Don't ask about
the "lower temperatures" - I never did get an answer to that question,
and that's simply the way the product is (or was at one time) formulated.
Sodium alginate is an anionic substance which forms aqueous
dispersions that are pH neutral. The sodium alginate and the CMC appear
to have a synergistic effect upon each other which results in a stable
and relatively inert lubricant.
I suppose some readers may be wondering how I know so much about
the *precise* chemical composition of K-Y Jelly... :-)
It seems that I once had the dubious experience of performing a
forensic chemical examination of what appeared to be traces of lubricant
on the clothing and perineum of an assault victim, and comparing same
with a tube of K-Y Jelly found in a search of a suspect's residence.
Johnson & Johnson, the manufacturer of K-Y Jelly, was cooperative in
providing chemical formulation data on this product. The essential presence
of K-Y Jelly on the victim was ascertained through IR spectroscopy. The
interesting part was that flame photometric determination (no AA was available
at the time) of sodium and calcium concentration from the victim's specimen
correlated almost exactly with the concentrations taken from the sample
seized from the suspect. With some help from J&J, it was learned that
enough sodium and calcium differences existed due to lot variation such
that based upon the above analysis one could state with reasonable certainty
that the K-Y specimen from the victim was consistent with the K-Y taken
from the suspect. At least it did not appear possible for the defense to
prove that the samples were *not* consistent. Fortunately, or unfortunately
as it may have been, I never had the opportunity to present this evidence
in court since the suspect plead to a lesser charge.
After the above experience, how could I ever forget the composition
of K-Y Jelly as long as I live? :-)
Larry Lippman @ Recognition Research Corp. "Have you hugged your cat today?"
************************************************************************
