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Essential Oil Evaluations and Applications.

Feb 28, 2022

One of the largest aspects, at least to many people when evaluating essential oil quality, will usually refer to a GC/MS report as to the tattle tale for their sole purpose of determining quality. These people will need to expand their scope of education to bring their thinking into line with current trends. This is the main trust of this discussion. I want to bring you up to speed, so to speak as to where things are going.

In many of the Analysis Specifications of various oils, such as the fixed oils or essential oils, one will notice that many times they are listing the various methods used to determine the evaluations run on the given sample. With Essential Oils the typical evaluations run are as follows. Keep in mind that these are not the only evaluations run, but the typical.

Refractive Index; This one determines how fast light travels through a medium. Usually that medium is a Refractometer. This also helps to determine the sugar content of a solution being evaluated. Many of you will be familiar with the term Brix. This is the alternative name to describe this process. This is a very effective method to determine the quality of a solution.

Optical Rotation; This is a method of measuring the rotation of light as it travels though certain materials. This measurement is determined by using a polarized source and a Polar Meter. Basically if a color and a path length is fixed and a specific rotation is known, then the information obtained using the observed rotation is used to calculate the concentration of the substance being tested.

Relative Density; This method is also known as Specific Gravity. This method is used to determine the ratio of a mass of a substance per unit of volume to a medium, usually water, at a given temperature. Several examples of measuring tools are as follows; Digital Density Meter, A Hydrometer, Hydrostatic Weighing, a Pycnometer, IE; a fancy term for a Specific Gravity Bottle, are among the more typical ones used. Some examples within this category that are measured and their weights; Water- 1.0, Olive Oil- .91. This is why Olive Oil floats on the top of water, IE; lighter than water. Also, Balsa Wood is a very light material, in this case a solid comes in at 0.2. On the heavier than water side, we see cement at 3.15, Lead at 11.35 and Depleted Uranium at 19.1. The Relative Density or Specific Gravity of Seawater is 1.025, Salt at 2.17 and Ice at .917. That is why Ice floats. Water weighs in at 8.34 pounds per gallon. Within this deal we also have several other methods that are used for specific purposes but actually are related to Relative Density. There is one method that I want to make mention of here for perspective and that is Buoyancy which is a specific type of measuring density. Buoyancy is the measurement of upward thrust that opposes the weight being pushed down. I am sure you have heard the idea that it is easier to swim in deep water than in shallow water. As the water gets deeper, you have a lot more weight opposing the weight of the swimmer, for example, pushing the swimmer down. I know it isn't a lot of displacement, but it does make a difference when it comes to scientific purposes. There are several things coming into play here, but I am just saying this, in this concept, for a general idea.

Other values measured outside of Essential Oils; Sometimes the above values will be assessed to Fixed oils, IE; Carrier oils. But with the Fixed Oils, IE; Carrier Oils we will many times see the following evaluations in addition to the above listed methods. Those are typically, but not limited to these;

Peroxide Values. This is the measurement of Rancidity.Any substance like this will begin a process of degrading. This is usually refereed to as Rancidity. Anytime you separate a portion of a whole, the whole thing begins to degrade. The big question here is; Where do you draw the line on the limit of Rancidity? Essential Oils usually don't go rancid, if they are of high quality. If they aren't, depending on the foreign substances in the sample, the oil can go rancid. But usually with Essential Oils, the big issue is Oxidation. But if this does happen, in some cases of working with certain issues with people, an Oxidative oil will be indicated for. So with Fixed oils, we tend to limit the Rancidity progression by keeping them cool, in dark places, etc. However, under not so good of conditions, I have seen a high quality fixed oil, having come from a healthy donor plant, go a long time before it really, actually becomes a concern. On the other hand, I have seen fixed oils come from known unhealthy donor plants and they go bad far too quickly for the given storage situations. So in reality this issue will trace back to the health of the donor plant.

Acid Values: This is a method that uses Potassium Hydroxide to measure a given chemical substance.

Free Fatty Acid: This measures the changes in Fatty Acids under a given circumstance.

The Saponification Value; This method uses the amount of either Potassium Hydroxide or Sodium Hydroxide required to "Saponify" under specific conditions. Basically how much of the before mentioned substances is required to make "Soap". Lastly to mention here is the testing of Moisture. IE; How much water is in the sample being assessed? This is one of the more important assessments. One of the big adulterants to Essential Oils is actually water. Using water to "water down" an essential oil is reasonably easy to do. Which I am going to avoid going into detail here, for obvious reasons. Another way to do this is to add a distillate water of the plant in a type of essential oil. The method helps to measure that possibility.

Different Examples of Various Substances;

I want to show you an example of a plant that produces essential oil and the values. That plant is the Fennel plant and the results of being a donor plant to the Sweet and Bitter Fennel Essential Oils from that plant. I will list it as follows;
Bitter Fennel - Sweet Fennel (Figures are generally found with these two oils and rounded). Bitter on the left, Sweet on the right.
18% 22%
71% 67%
Refractive Index
1.534 1.531
Optical Rotation
16.37 20.60
Relative Density
0.970 0.950
As you can see the Fenchone and the Trans-Anethole have a direct relationship. As one goes down the other goes up. From looking at averages one can conclude that it may not make much of a difference. But in this case, it does. But what is more revealing is the 3 assessments after the two components. If we know the ranges for Fennel, then we can clearly see that both samples are Fennel, if we used a chart comparison according to the Refractive Index. The Relative Density would also be used to confirm the evaluation. But the big difference in revealing the difference between the two is the Optical Rotation. Here we see the polar rotation being vastly different and that is where we confirm the difference between the two types, Bitter and Sweet. Based on other discussions I have had in this format, the Sweet is usually grown in soils that are higher in Potassium and Bitter Fennel is usually grown in soils higher in Nitrogen.

From my own experience in working with people infected with Trypanosoma brucei, (Leishmania), which is a Gram Negative deal. We also know that T. brucei is negatively charged, so when we come in with a positively charged element, Potassium, which is found to be the case with Sweet Fennel, we get remarkable results. Sweet Fennel works remarkably well against this pathogen. BTW, this is one of the few known pathogens that can cross the Blood/Brain Barrier. We see this coming through with what be observe in the Optical Rotation numbers. BTW, the rotation in the Bitter Fennel will be opposite of the rotation found in the Sweet Fennel. I know in one previous discussion that I said that the Nitrogen/Potassium aspect doesn't affect the Fennel plant that much and it is true in light of the comparison to the plants being compared and contrasted in that discussion, but in reality it actually does make a difference in the manifestations of the Fennel Oils.  The 4% inverse relation doesn't mean much in some oils, but in Fennel it makes all the difference in the polarity and in turn the rotation.

In the previous paragraph I mentioned the particular parasite, Leishmania. This is a parasite that is found world wide. It can affect all life forms around the globe. Some people in areas where the Nitrogen rich soils are found, get this parasite too. But still the positively charged Potassium based Fennel oil seems to do the best job in all areas where this parasite is found. Usually in the present time frame, this issue originates in areas of dry, hot environments where we do not find a lot of rich Nitrogen containing soils. So to make a long story short, plants rich in Potassium tend to work well with this issue. So as a result of this, one would not find a lot of success in using an EO that is higher on the Nitrogen containing elements and lower on the pH scale, thus carrying a Negative charge, in working with this before mentioned issue. Best course is to use an oil or oils that are higher pH, higher on the Potassium side and carrying a Positive charge.

I hope I have conveyed several aspects to how essential oils are looked at and used in today's setting. This discussion is presented for perspective.

Thank you for your time and interest.

End of Discussion. KK.



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