MEXCHEM2006 - 6-10-2007 at 17:14
I have a problem with a product that we make its name its agave syrup we make it from the plant Agave tequilana Weber ..
https://sciencemadness.org/talk/viewthread.php?tid=7723&...
recently we are having problems with people that are selling their product as agave syrup but we know its fake , its made with high fructose syrup and
Xanthan gum , i know that you can make a chemical breakdown and find out the content but i would like to find out a way to do a simpler test ,
finding a way to destroy the xanthan gum and that way it will separate in two phases showing that its a fake.
Any suggestions are welcome
JohnWW - 6-10-2007 at 17:34
If it was fermented to supposed "pulque", and then distilled to make supposed "tequila" (pulque brandy), the result would be a product quite different
in taste and chemical composition (especially as regards the content of higher alcohols and esters, determinable by GLC) from genuine Mexican tequila,
which presumably has a well-known and very limited compositional range.
solo - 6-10-2007 at 17:36
Agave syrup consists primarily of fructose and glucose and the fake syrup is fructose and xanthan gum.......so just do a test for glucose sugar and if
there is none then test done.....there are simple dip sticks used to detect sugar in the urine , also the market glucose test....a zero glucose would
mean it's not the real thing of course assuming xanthan gum doesn't have free glucose........solo
Reference Information
Xanthan Gum
Prepared at the 53rd JECFA (1999) and published in FNP
[Edited on 6-10-2007 by solo]
Attachment: XANTHAN GUM.pdf (143kB)
This file has been downloaded 988 times
not_important - 6-10-2007 at 17:40
Might look at this
http://a257.g.akamaitech.net/7/257/2422/14mar20010800/edocke...
Xanthan gum solution have a decreassing viscosity with increasing shear, so tests on that might give it away provided that the viscosity increasing
components of agave syrup don't have similar behavour.
what about optical activity - rotation of the HFCS vs real agave syrup, or is the fructose content of agave too close to that of the ersatz syrup?
The data I can find lists from 93% fructose + 7 glucose to around 50/50 fructose/glucose. HFCS has glucose in it, too, so a simple test for glucose
won't work; common HFCS ratings fructose/glucose are 90/10, 55/45, and 42/58, I've also seen 95/5, so making a mix that matches agave's main sugars
may be rather simple.
[Edited on 7-10-2007 by not_important]
JohnWW - 6-10-2007 at 17:48
Yes, that is right. Besides a chemical test for glucose in the syrup (see e.g. Vogel's Practical Organic Chemistry), a quicker way may be to measure
the optical rotatory dispersion of solutions of known strength of the syrup. Glucose (which has to be present in substantial quantities), fructose
(used in fake syrup), and sucrose (from cane sugar, which would probably also be used as an adulterant), have differing optical rotatory dispersons
for the same concentrations.
The same chemical and optical rotatory tests could also be used to tell whether supposed maple syrup, produced mostly in eastern Canada and the
northeastern U.S.A. by tapping the sap of maple trees in early spring and boiling it down, is genuine, fake, or adulterated,
Ozone - 6-10-2007 at 19:49
IIRC, xanthan and starch exhibit a synergistic increase in viscosity. Perhaps compare the viscosity of your agave + 1-5% starch with the suspect
product at equivalent brix (and a control) with the same amount of added starch. The suspect product should exhibit a much greater viscosity. This
could be measured with a capillary viscometer (requiring little special instrumentation, just a capillary (or better, ubellolde?) and a stopwatch.
If you have a cone and plate (or spindle) shear viscometer, this could be compared with the thixotropy described by not_important for a more
definitive answer.
A calibration curve could likely be made.
Just a thought,
O3
[edit]
Thanks not_important! I am out of town just checking in, so I did not have time to read your attachment. Glad to know that I'm not nuts, though.
[Edited on 7-10-2007 by Ozone]
MEXCHEM2006 - 6-10-2007 at 21:20
To JohnWW
Pulque is not made with Agave tequilana Weber , and Agave syrup is a sweetener , not recommendable to use it in tequila production ,even if you use
it for tequila it would not give the same flavor as the real tequila because the agave syrup is a purified form of a agave extract so it already lost
alot of the main ingredients of Agave .
Here is a link to our web page (hope you understand spanish)
http://www.valleagave.com/
To Solo
High fructose syrup has a given amount of glucose (as the other guys already pointed).
I will try with the optical activity , it seems to be a faster-better way to go.
Thank you all for your help , i will do the test as soon as I get back to my country , and I will let you know the results
[Edited on 7-10-2007 by MEXCHEM2006]
[Edited on 7-10-2007 by MEXCHEM2006]
not_important - 6-10-2007 at 23:40
@Ozone, the link I gave is for a set of standards for xanthan gum, which includes a test using locus bean gum as a synergistic thickener. Locus bean
and guar gum both interact with xanthan gum much more than starch.
feacetech - 7-10-2007 at 12:54
you could try a refractometer and get a brix reading
chemrox - 7-10-2007 at 18:56
Man you've got some beautiful stills!!