The plant is highly automated and
run by two operators per shift,
24/7. It’s built much like other
modern milk drying plants but
with a smaller capacity of 500
kgs of finished product per hour
compared to 8 tonne/per hour at
some other plants.
After the milk is collected it is
concentrated using an evaporator.
This is essentially a vacuum to boil
off the water at a low temperature
which reduces the products
exposure to temperature.
The concentrated milk is then
passed through a spray dryer,
where it is sprayed into a large
vessel of hot air. This evaporates
off the remaining water and passes
the powder out the end.
“The main pieces of equipment are
custom made, but the basics of
the design is relatively standard,”
says FoodWaikato business
development manager Craig Hoare.
“The equipment is assembled on
site by the Tetra Pak engineers. The
product is enclosed in machinery
through the whole process from
milk reception right through to
being packed out as a powdered
product.”
This machinery was chosen
because it allows flexibility in
processing and control of the
temperatures the product is
exposed to.
“This allows us to influence the
properties of the finished product.
For some applications a high
temperature treatment is beneficial,
for others it is advantageous to
keep the heat treatment as mild
as possible. The FoodWaikato
dryer has the ability to control
the composition of the final milk
powder, to adjust the fat and protein
content. There is also the ability
to add powdered vitamins and
minerals, and if necessary even oils
to produce an infant formula base.”
Over the years the requirements
around hygiene have changed.
Something that is especially critical
when making food for infants.
“Standards in the dairy industry
have increased greatly, and new
bacteria have been identified
that can cause problems with
very young consumers. These
pathogens require a great deal of
focus to control,” says Craig.
A new spray dryer, which Spring
Sheep will have access to, is
Scottie Chapman, CEO
of Spring Sheep Milk Co
8 APRIL / MAY 2020