Emu oil is derived from the fat of an emu bird. The emu oil has
good penetrating properties into human skin due to its high linoleic
content plus it is naturally bacteriostatic. A number of health
related products are becoming available to the general public
in the form of processed oil for burn patients, hand lotion, therapeutic
creams, soaps and shampoo.
Processing
of the oil has been challenging. Initially, the oil has an offensive
odor and a brown color typically caused from protein sources such
as bones and blood. Headland Oil Processing Company, (HOPCO) wanted
to refine the odor and color in a natural physical way as oppose
to a caustic reaction. They also wanted to do this on a pilot
scale to allow small ranchers of the emu to be able to process
their own birds and receive their oil in return. Previously, processors
would mix all of the different ranch birds together, then divide
up the oil on a percentage of how many birds were brought in.
Since the bird's diet and lineage will dictate the quantity and
the quality of the oil, the producers wanted to get the oil only
from their birds.
HOPCO, decided to build a small operation. The process starts
with removing the fat from the bird and blending. Typically about
20 pounds of fat can be removed from each bird. The fat is then
put into a heated tank and brought to 150º F very quickly to reduce
peroxide growth. Then it's stirred for about 20 minutes. The heat
melts the fat into an oil and the oil is then strained to remove
crackling. It is then run through a finer filter before going
to the rendering tank. In the rendering tank, it is mixed with
diatomaceous earth and absorbing clay. The clay absorbs the peroxide
and refines the color and the diotonatious earth helps to filter
the oil. Depending on the peroxide level, the oil may be run through
the rendering tank a number of times. The tank is kept at a slight
vacuum to reduce peroxide growth.
To
remove the odor and not destroy the penetrating properties of
the oil requires a special distillation process that lowers the
pressure, which therefore lowers the evaporation temperature.
After trying other vacuum distillation techniques, it was found
that a high vacuum centrifugal molecular still gave the best results.
The still was used to make a light end cut of about 3-5%. Tocopherals
are used as a preservative and are added prior to distillation.
The Myers Vacuum model Pilot 15 was chosen for its compactness,
easy connections, and mobility. This system was found to be better
than other types of vacuum stills because of the very short residence
time on the heated surface. The Pilot 15 processed about 4-5 gallons
per hour. Larger systems are available for scaling up.
High vacuum centrifugal molecular distillation is a process designed
for separating heat sensitive, high molecular weight material.
It features applying a very thin, continuously moving film on
a heated rotor under high vacuum and placing a condensing surface
a short distance away. The residence time on the heated surface
is measured in parts of a second. This allows the user to make
very fine cuts with the least amount of decomposition from heat.
Material enters the Pilot 15 using a variable speed gear pump.
This will regulate how thick the film will 
be on the rotor. Material flows from the pump into a falling film
degasser chamber. A mechanical pump with a liquid nitrogen cooled
trap pumps the heated degasser chamber. The fluid from the degasser
enters a second transfer pump and is pumped to the high vacuum
chamber. A liquid nitrogen cooled trap, an ejector diffusion pump
with a mechanical pump backing it, pumps the chamber. Material
is routed to the center of the rotor, which in this case is heated
to 390º F. The material spreads out in an exponentially expanding
manner to give maximum surface area in the shortest time. Light
ends, in this case odors, evaporate off and are condensed on the
water-cooled condenser where they are drained and pumped out by
the distillate pump. The oil that did not evaporate, runs over
the edge of the rotor and is collected by the residue pump. 3-5%
of the original material is removed as light ends. They are either
collected in the liquid nitrogen traps or in the distillate tank.
Approximately 5 gallons per hour can be processed continuously
through the Pilot 15.
In conclusion, the whole refining process requires
constant vigilance to minimize odor. The key step of removing
odors is utilizing the Myers centrifugal molecular still with
its short residence time on the heated surface.
About the Author: David
Casilio earned a BSEE from Clarkson University in 1980. He was
with CVC as a senior project engineers in thin film evaporation.
He received a Masters of Science in manufacturing technology in
1990 from Rochester Institute of Technology. He joined Myers Vacuum
as vice president in 1994. He manages the Rochester production
facility and is in charge of sales of the distillation product
line.
Other links of interest
EMU Oil Institute Web site
www.emu-oil.com
The Latest Technologies Come to Emu Oil Refining
by David L. Long, President of Longview Farms, Bloomsburg, Pa.:
http://www.emu-oil.com/EmuOilTestArticle12904.htm
For more information on use
of Myers Molecular stills for refining EMU oil:
http://www.emu-oil.com/MDoil.htm
Myers
Vacuum