What is a GC ??

[Guest guest]

Hi y'all,

 

Another old one .. might answer some unasked questions. And that's it

for now .. gonna go home and relax with a good book. ;-p Butch

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Based on the fact that we got some new folks on the list that wanna

learn about essential oils and such, here is the reply I made a few

minutes ago to another list .. to a lady that asked me what a GC was ..

 

> What's a GC test?

 

I'll try to keep this short .... not easy for me .... :-( GC means Gas

Chromatography - it's an analysis of an essential oil to determine the

chemical profile - sort of like a blood test but a lot more complicated

and more expensive. We also have a test called GC/MS which is GC plus

Mass Spectroscopy - which I prefer, and to simplify it's a mass detector

to determine the molecular weight of a given chemical component.

 

We can go into Specific Gravity, Refractive Index and Optical Rotation

which are further tests to determine the purity and quality of an oil,

and most of my wholesale customers - and some retail - want copies of

these ... and they get them.

 

There are a dozen or so techniques other than GC/MS, Infrared or Planar

Chromotography being a couple of those in fairly common use, but GC/MS

is the established and reliable technique for analyzing essential oils.

 

Another technique GC/FT-IR, which stands for Gas Chromatography/Fourier

Transform Infrared Spectophotometry. This technique is also useful for

the analysis of EOs since it's possible to create libraries (archieves)

or use commercial libraries during the analysis. But it is also not as

popular and simple as GC/MS and it doesn't help the one paying for the

analysis as much as it does the analyst.

 

I'll stick to GC/MS as it's the widely accepted technique and unless I

get into something technically deep - and that's not likely as I'm not

into chemistry projects, it's as much as I'll ever need - or pay for.

 

The finest equipment can be defeated by a weak analyst - technicians

must know what they're looking for and they have to know the standard

for comparison - that is, what should be the profile of a typical sample

of Origanum vulgare produced from wild-grown plants harvested in Central

Anatolia or the expected results of a Lavandula stoechas from France

versus one from Turkey - there will be differences, and that's a very

important reason to know the ORIGIN of an oil.

 

I have all of my oils GC tested for a number of reasons but for the oils

we produce here in Turkey, it has nothing to do with determining if the

oil has been adulterated - I know it hasn't as I know it came directly

from the still. But I am looking for the chemical profile to see if it

fits within the " footprint " or " range " that we think is acceptable for

that oil because even a pure oil can be a mediocre oil.

 

Mediocre oils are (should be) sold as Commercial Grade oils to the food

and pharmaceutical and soaping industries because when they get through

playing with them, they will have lost part of their original identity

anyway. Unfortunately, many of these lower grade oils make it into the

market as Aromatherapy Grade ... :-(

 

As I'm able to contract my distillation here in Turkey, I test so I can

avoid accepting Commerical Grade oils - my target is the AT industry.

 

Smart chemists can fool a GC but distillers from third world or emerging

markets don't usuall have the technology to manipulate oils like this

and probably wouldn't mess with it if they could as it's expensive and

time-consuming. The more " sophisticated " countries are normally the

ones to adulterate oils .. and the ones doing this adulteration are the

chemists we pay to analyze our oils .. they are the experts. ;-p

 

The French are extremely good at this, especially with their 40/42

lavender which is manipulated by man in a well-equipped laboratory - the

Great Spirit doesn't allow the same growing conditions year after year

but they want consistency in that lavender so they doctor it up a bit.

It takes more than GC/MS to detect this - but Chiral Column testing can

usually do it if the analyst is experienced. Normally, folks don't try

to deceive you, they just sell their 40/42 and it's up to the buyer to

know what they're getting because the sellers of 40/42 lavender often

don't know themselves what they have - like I've said and written many

times before, Caveat Emptor ....

 

An experienced analyst looks for what's not there as much as for what's

there - if you increase one side of the equation, you will decrease the

other side - pure physics. The absence of a chemical that's normally

detected at .01% tells a lot to the smart analyst. If I increase the

major chemicals to get a more favorable product, I'm lowering the per-

centage of minor trace components - and we don't really know exactly why

a particular oil has therapeutic value but we can bet that the Great

Spirit didn't put any unnecessary crap in that oil just to fill a void,

so we logically conclude that upsetting that natural synergy will have

negative effects on the therapeutic value.

 

Most people will tell you their oils are GC tested and that is normally

pure hogwash. Generally, they're told that by their source and they

believe it (want to believe it) and just pass along the information.

They are generally niave, not dishonest, but I personally see that as

also being just a little bit irresponsible because I believe we should

trust everyone but always lock our car. I've sold lots of oils in 100

kilogram lots, and never without providing a GC test because big buyers

want this and I also want it because I guarantee that all my products

are pure and unadulterated and my name is far more important to me than

money. I'm not greedy, I just try to keep my credibility propped up as

that's an inherent part of my interpretation of what's ethical and moral

when dealing in Aromatherapy Grade oils...

 

So .. folks buy those bulk oils from me and sell to wholesalers who pass

them to retailers who pass them to end-users, and I'll bet you a pretty

that you cannot get a copy of that original GC test that I gave the bulk

buyer - the first buyer! Why? Danged good question, huh? We can

guess the answer has something to do with identity change - the oil

profile may no longer resemble the original GC analysis. It's not your

retailer who is messing with those oils - your retailer is also a victim

but they are helping to victimize themselves by not demanding a copy of

that GC!

 

If someone tells you their oils are GC tested, ask them to put up or

shut up. They'll probably give you a lot of shuck and jive but no GC!

Would you buy a refrigerator or car without a warranty? Would you buy a

pedigree dog without the AKC papers? People do will buy oils without

proof of purity. If the seller trusts their product, they will have the

bottles marked with a Lot Number and that Lot Number will correspond to

a Lot Number on the GC test. Also, that seller will give you a copy of

that GC if you want it - free! It doesn't matter whether or not you can

read it but it should give the seller a high pucker factor if they're

willing to risk passing on a phoney GC because some end-user or some

competitor might just get that oil analyzed and expose them as a fraud~!

 

Without Lot Numbers there is a great potential for a seller to create an

alibi of error but with Lot Numbers, when they're caught short they have

no avenue of escape. Folks who buy my oils wholesale and then rebottle

can guarantee what they sell and can give you a copy of the GC test for

that oil - if they don't, then I will stop selling to them because they

are messing with my oils and I don't want to see such oils advertised as

being Origin Turkey or Origin Anatolian Treasures! But if they buy only

16 ounces from a source that doesn't provide them a copy of a GC, they

can't afford to pay $150 and up to test only 16 ounces of oil so they're

running on luck and/or guts.

 

As I wrote above, I know most laypersons can't read a GC so I generally

have the analyst make comments at the end that can be understood by the

average buyer. Also, as I refuse MANY of the oils I test, I have tests

of mediocre oils and the reasons for the refusal .... point being you'll

only see good GCs because the oils with bad GCs aren't offered for sale

by folks. Think of that instead of wondering why someone only shows off

their good oils .. if they're honest, that's the only one they have.

 

I am not going to say that folks making soap need to buy tested oils

because they can get by with Commercial Grade oils .. and I'm speaking

purely from a point of safe use. BUT - if the oil you are buying for

making soap contains 50% synthetic chemicals that cost $5 a kilogram and

you are paying $50 a kilogram for that oil, then it's no longer a matter

of just safety - it's a matter of you getting ripped off. Take my word

for it .. MANY people and companies in this industry have been caught

selling adulterated essential oils .. it's a matter of greed.

 

All (including Commercial Grade) unadulterated essential oils are safe

if used correctly and responsibly but some require a lot more attention

to detail - like cinnamon bark. Adulterated oils can be harmful

depending on the nature of the adulterant used and some folks aren't as

ethical as others - this holds true for Fragrance Oils as we have no

idea what they contain because the industry has lobbied for the right to

keep the ingredients as Trade Secrets.

 

Likewise, a pure oil can be dangerous if the user is careless or

irresponsible. No difference than guns or cars.

 

Was the explanation short enough ?? .. ;-)

 

Y'all keep smiling, Butch http://www.AV-AT.com