Processing & Factory
DISTILLATION
We consistently strive to produce high-quality Essential oils. We have the right equipment and expertise and procedures to ensure that standards are maintained. HEO started with 2 x 1000 litre stills and expanded to 28000 Litre distillation capacity.
Our stills range from a 100 litre to 7000 litres capacity.
Three types of hydro distillation for isolating essential oils from plant materials are used.
1
Direct steam distillation
2
Water distillation for powered products eg. Iris roots
3
Water and steam distillation.
Our factory is situated on our farm, therefor the distance from harvest to distilling is at a minimum.
Rose Extraction & Cohobation
Cohobation is a process that can only be used during water distillation or water and steam distillation. It uses the practice of returning the distillate water to the still after the oil has been separated from it so that it can be re-boiled. The principle behind it is to minimize the losses of oxygenated components, particularly phenols which dissolve to some extent in the distillate water.
As this material is being constantly re-vaporized, condensed and re-vaporized again any dissolved oxygenated constituents will promote hydrolysis and degradation of themselves or other oil constituents and therefor temperature control is of absolute importance.
When rose oil is extracted during water distillation, the one main constituent – phenyl ethyl alcohol – dissolves into the water of the distillation still and does not form part of the essential oil that is so extracted.
The oil so extracted is therefore not whole, and is deficient in this rose-smelling ingredient – and in order to produce a “complete” oil, the phenyl ethyl alcohol needs to be distilled from the water in which it dissolved and added back to the “incomplete oil”.
With cohobation this phenyl ethyl alcohol is so distilled, that it is added back to the original distillate, in the correct proportion, to form a complete and whole rose oil, and is then called Rose Otto.
Extraction
Some plant material is too fragile to be distilled and an alternative method must be employed. Solvent extraction is the use of solvents, such as petroleum ether, methanol, ethanol, or hexane, to extract the odoriferous lipophilic material from the plant. The solvent will also pull out the chlorophyll and other plant tissue, resulting in a highly colored or thick/viscous extract. The first product made via solvent extraction is known as a concrete. A concrete is the concentrated extract that contains the waxes and/or fats as well as the odoriferous material from the plant.
Hexane extraction is used to take the rest of the oil out of Rosehip cake on contract basis. Extraction of Marigold flowers are done on contract basis for xanthophylls and are the main natural source of xanthophylls.
A rectification column is used to purify the solvents before extraction.
Cold Pressed Factory
For Kalahari melon
In 2016 HEO started with a cold press factory to produce high quality Kalahari melon seed oil. This can also be used to produce other oils on contract basis eg Rosehip seed oil Cold pressed, which is the method usually used for delicate oils, means that they are expeller pressed, but in a heat-controlled environment. The temperature is kept below 60-65°C. Care is taken that the seeds are pressed safely at a cool temperature to protect the oil from rancidity, trans fats, and other toxic processing chemicals and therefor keeping the acid value also relatively low. So there is no need to refine.
The oil is precipitated and filtrated. Using low-heat methods produced higher quality oil, albeit in lesser quantities. A screw press made of high quality steel, that is wear-resistant and easy to clean, are used.
Drying Facility
For drying Pelargonium sidoides and Iris rhizomes, Artemesia afra & other plants materials.
Laboratory
Highland Essential Oils has a small well equipped laboratory to do basic experiments for research and development. Distillation and extraction laboratory equipment make is possible to do small scale experiments before expanding to commercial scale production. A Buchi rotary evaporator is used to meet the essential needs in evaporation. Different glass apparatus eg different Clevenger apparatus and condensers are used Solvent extraction at HEO is used for the extraction of Rose flower concrete, Rose leaves concrete, Iris flower concrete.
Nursery
Highland Essential Oils has a small nursery where we propagate seedlings as well as cuttings organically.
