Tests done on all oils
Additional tests for 100% pure oils
Tests to ensure that no chiral molecules exist that could be missed by GC Mass Spec to verify the natural status of an oil. Typically an oil is optically active – thus natural.
The pinnacle of analytical technology, which will detect certain adulterations missed by a C-14 isotopic test. Performed only in the qualification stage of new source materials as opposed to batch to batch, this test compares the isotopic ratios in the test material versus a known standard to identify if the product is “in agreement” with a product of natural origin. This is critical in ensuring that the product is 100% natural and not adulterated with natural or synthetic isolates.
For example, this technology can be used to determine the origin of vanillin in a vanilla extract. Vanillin which is naturally occurring in vanilla beans, could be stretched by the addition of biotech natural vanillin. This test will catch such adulteration.
Using a refractometer, this is a measurement of how light moves through the sample oil. This test ensures consistency between batches of essential oils.
Performed to detect the presence synthetic compounds, which are often used to adulterate essential oils. This is critical in ensuring that an oil is confirmed to be 100% Natural.
For example, adulteration of lavender oil with small amounts synthetic linalool and/or linalyl acetate would be revealed via Isotope C-14 Carbon Testing.
Also a test of consistency between batches of essential oils however, specific gravity is also a reliable indicator of variation in the constituents of the oil.
For example, if the oil has been adulterated with low boiling terpenes, the specific gravity will be lower versus a 100% unadulterated standard.
Performed to ensure that no banned agricultural residues are present in the final oil. This test also tracks the levels of agricultural residues present – even at acceptable levels. This can be used to foster sustainability initiatives to partner with growers in developing alternative pest control methods.
The most subjective tests performed yet highly critical. Since essential oils are complex natural mixtures by definition, they can vary greatly from batch to batch depending on growing conditions, region of harvest, distillation/processing techniques and equipment, age and more. This will not only affect the physical characteristics of the oil (color, composition, etc.) but will also impact the taste and odor. Vigon performs these very subjective tests, against a retained standard, under ideal conditions, and by at least two trained lab evaluators.
- Color and consistency are evaluated against standard.
- Many essential oils are food grade, and used for food flavoring purposes (according to FEMA GRAS guidelines). Tasting a food grade oil may detect defect, that no other test can catch.
- For example, an oil that may be unusually bitter would be detected here.
- Odor is an important another critical and subjective test, that can catch issues that instruments simply cannot.
- For example, an oil that passes all physical testing, may sometimes bear a burned off-note. This is typical of lots that are “too fresh”. Such lots need aging, nitrogen purge or simple agitation to mature, prior to sales.
Performed to ensure that the oil is free of any elemental impurities that may come from the soil in the region of harvest or equipment used in the processing of the final oil. This is particularly important with essential oils where the freshly harvested product is field distilled to a crude oil prior to final rectification.
Provides a roadmap of an essential oil by vaporizing it in an injector port at approximately 250°C. Then a small amount of the vaporized oil is “carried” onto the column via an inert gas. The column is either polar or non-polar and will vary in length, inside and outside diameter, and phase thickness. Each of these characteristics will affect the quality, separation, and resolution of the final graph. Based on the polarity of the oil and column, the carrier gas will push the vaporized oil through the column and ultimately pass it through a detector. Many companies use a Flame Ionization Detector (FID) which in a very basic sense, burns the isomers and based on the amount of carbon present – converting the energy from the burn to an area percentage.
One slight drawback is that if an oil contains isomers that don’t burn, the overall area percentage can be skewed. This is why GC alone cannot be the sole quality criteria for assessing the quality of an essential oil. It is one very critical step of the many listed here to ensure the quality and integrity of an essential oil. The resultant graph can be compared with a known approved standard and will quickly reveal if isomers exist in the oil that do not belong or are missing – or if they are present at levels greater or less than what would typically be found in nature. A trained analyst can quickly detect many forms of adulteration in an essential oil using gas chromatography. Vigon employs analysts with over 25 years of experience in the interpreting GC data of essential oils.
Uses infrared light at specific, predefined frequencies which when shone through an oil, provide a “snapshot” in the form of an absorption pattern. This absorption pattern is the amount of light absorbed by the oil at the given frequency and can be compared to an approved standard to measure the potency and consistency of an essential oil.
For example, a very common adulteration is the addition of a small percentage of a carrier oil (such as castor oil), which is invisible on GCMS and not necessarily detectable by a Specific Gravity test. FTIR detects such adulteration.
Uses a gas chromatograph as indicated above, however the detector (mass spectrometer) fragments the molecules using electricity which measure the mass of the molecule. Once the mass is determined, the molecule is compared against a library and the molecule can be identified. GC/MS is extremely valuable for identifying unknowns, monitoring key markers, and ensuring the overall profile meets established standards either published or internal.
GCMS, however, may be unable to detect adulterations such as: addition of certain carrier oils, small addition of synthetic molecules identical to naturally-occurring components.
Performed on applicable essential oils to ensure that no microbial growth is present. Many essential oils are anti-microbial by nature, however there are some hydro-distilled oils that can support growth and are therefore tested against a full screen of microorganisms.