What Is a GC ??

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Hi y'all,

 

Here is a part of a post I have made to this list many times before.

 

> 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.

 

(I'll add here that the above three indicators do NOT mean an oil is

pure .. but only that its within the range normally expected)

 

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

Chromatography 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 (archives)

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 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

Aromatherapy market ... :-(

 

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

avoid accepting commercial quality oils - my target is the AT industry.

 

Smart chemists can fool a GC but distillers from Third World or Emerging

Markets can't manipulate oils like this and wouldn't mess with it if

they could as it's too expensive and time-consuming. 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.

 

I've sold lots of oils in 100 kilogram lots, and I've never exported

an oil without providing a GC test because big buyers want it and I want

it because I guarantee that all my products are pure and unadulterated

and my name is more important to me than money. I 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.

 

BUT, those who buy those bulk oils 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!

 

Many of my wholesale/retail customers ask for GCs on new oils I sell -

not that they can read them but they want them. ;-) I sometimes have

the analyst make a statement at the end in lay persons terms and that

gives them warm fuzzies.

 

(New info .. I've recently contracted with Mustafa Kemal University here

in Turkey .. they'll be doing most of my analyses in the future .. that

includes retesting some oils I have now that have been tested)

 

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. Likewise, a pure oil can be dangerous if the

user is careless or irresponsible.

 

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

 

Bulk/Wholesale/Retail GC Tested EO, Rose Otto, Hydrosols, Rose Petal

Jam, Turkish Robes and lots of other nice things.