APRC has the latest in automated physical constant testing, including the following:
Optical rotation tests for chirality by measuring the amount of light bend produced by the orientation of the essential oil molecules to determine whether the molecular structure complies with the determined standard.
Measured using a densitometer, the specific gravity of an essential oil is the density of a particular oil in comparison with the density of water. Specific gravity readings are measured at precise temperatures and pressures, as temperature and pressure can impact the measurements. Particular oils have known ranges of specific gravity in which the oil is considered to be unadulterated and pure.
The refractive index of an essential oil is a measurement that tests how the speed of light is altered when passing through the oil. An oil's refractive index can be compared to that of a reliable sample.
This instrument is use to take the subjectivity out of color comparison and evaluation. A colorimeter is an instrument that compares the amount of light getting through a solution with the amount that can get through a sample of pure solvent. A colorimeter contains a photocell is able to detect the amount of light which passes through the solution under investigation.