The Rural Voice, 1996-04, Page 33used at Sunfield, and the
solvent extract systems
which rely on chemicals to
dissolve the oil away.
The former system was
used exclusively in the '40s
and '50s, says John, but
screw presses get down to
six per cent residual oil
while solvents get down to
one per cent. Up until the
mid 1960s the only reason
to process was to get the oil
as the meal had no value.
Because the solvent could
take out extra oil it became
the preferred choice and the
mechanical system sort of
disappeared, said John.
What has made this
system viable once
again is the
changing
nutritional requirements of
livestock with higher
performance genetics.
"Pigs and poultry need an
energy -dense diet to support
the genetics so farmers have
started supplementing their
diets with fat. There was a
demand driven requirement
for a ration with energy.
Soybean meal was now
much more attractive for a
feed manufacturer."
The other change John
says, was the processing
update using the screw
press. "It lends a greater
efficiency to processing.
The old system put through
about eight to 10 tons a day.
By combining extrusion and
screw pressing, 20 - 25 tons
per day per line can be
achieved. This is
significantly energy and labour
saving."
The first step in the processing of
the beans is the removal of the hulls.
The beans are then dried and put
through the extruder which takes
ground up beans, heats and
compresses them, then forces them
out a small orifice. At this point they
are in a semi -fluid stage, resembling
porridge.
The beans are then put through a
screw press which is a heavy duty
auger, surrounded by a perforated
cage. The rotating action of the shaft
The extruder (with a guard removed for viewing) heats and
compresses the beans. Sunfield is a family business, right
down to clean-up by young members of the family (below).
forces the oil out the slats. The oil is
then filtered and the meal ground
before shipping.
"Probably 90 per cent of the mcal
stays within 50 km of here and 80 per
cent of the beans come from the same
geographic radius," says John.
The oil moves into the edible trade
where it's processed into commercial
shortening used by the restaurant and
bakery trade.
Most crushers produce a 48 per
cent protein meal, though the
Underwoods' is 46 per cent protein
and six per cent fat. The majority
flows into monogastric feed
markets for pigs and poultry.
Oil is shipped from the plant
every other day. Sunfield is a
kosher certified plant meaning
the oil produced is suitable for
manufacturing into products
acceptable to the Jewish
communities.
"Another interesting aspect
is how technology is going to
change the face of agriculture
over the next few years —
while major crushers do an
excellent job of producing a
quality product in Targe
amounts, they want to keep it
very homogenous.
"Research on the other hand
is offering more options on
what farmers can produce.
Research is being done on
growing crops for the energy
trade and pharmaceutical
products. There is a real
divergence there which
creates an opportunity for
places like this to take
advantage."
John says there is also a lot
of focus on changing fatty
acids, so they are modifying
the percentages to give unique
characteristics such as
improving internal processing
efficiencies to create healthier
oils, or increasing stearic acid
for a different end result
"(Farmers) are no longer just
producing beans, but beans
that will have a target
market," he says, adding that
this type of research is also
happening in other crop
products like corn and canola.
"We went through an
industrial revolution in my
father's day from horses to tractors
and automated production. Then
there was the chemical revolution and
and now I see a biotechnical stage.
Some may argue that we are getting
ahead of our time, but the other side
is that we are just speeding up
Mother Nature's process."
There is an advantage to smaller
processors, John says, in that it's
easier to do a small run for one
company. "Large processors can't
justify that. If they can't do a large
number of bushels it's too
insignificant."
APRIL 1996 29