HYGIENE KEY
TO DAIRY OPTIMISING OPERATIONAL EFFICIENCIES
The word ‘hygiene’ can
cover both the need
to keep everything
clean and to avoid
cross-contamination
of ingredients. Manufacturing
systems that were suitable a few
decades ago are now proving to be
cumbersome and not at all flexible
to meet the demands of today’s
marketplace. To remain competitive,
it is necessary to offer a vast array
of products to the consumers.
This means that manufacturing
processes need to be agile to
ensure that only the right amount of
product is manufactured at the right
time and that you are not creating
Inventory to do so.
When handling milk powder-based
products, there are several risks that
add to this complexity:
• Residual product from previous
recipes can remain inside
the processing and handling
equipment, which then
contaminates the next batch
through the system.
• Cross-contamination can occur
from airborne dust returning back
into the system through open
hoppers and exposed transfer
points or by operators.
• Bacterial growth can occur due to
moisture still being present in the
system after wet cleaning.
• Traditional long pneumatic
conveying and coupled mixing
lines represent a major risk.
These are awkward to clean,
and thoroughly removing any
trace of a previous recipe is very
time consuming. When this is
completed how can you swab test
each surface to ensure it is safe?
Commonly entire shifts can be
used for cleaning down, before
a change of recipe is allowed,
which adds significant costs to the
finished product and inflexibility to
the production line.
In order to reduce costs and keep
the number of clean-downs to a
minimum, some companies opt
for campaign manufacturing:
setting their production schedule
to start with the ‘blandest’ recipe
and getting progressively stronger.
When producing dairy
based products, it is of
utmost importance to
ensure the highest of
hygiene standards. This
can be an expensive and
time-consuming activity,
but the risk of not doing so
properly is far too high.
This is often referred to as ‘white
to black’, but this just results in
Inventory and has its own risks
of wastage in respect to shelf-life
expiration.
A real case for
hygiene
A major manufacturing company,
Brothers Illong, who supply the
Chinese dairy industry with specialty
raw materials and blends for the
manufacture of high quality products
for both children and adults, was
facing these hygiene issues. With a
backdrop of a number of scandals
in the Chinese dairy industry at
that time, they put hygiene and
clean-ability top of their list when
looking to invest in expanding their
production capacity. They certainly
didn’t want to find themselves in the
news headlines.
At the time of their expansion, they
had four static ribbon mixers of
different capacities ranging from
500 kg to 3000 kg, which matched
their order requirements and were
designed to keep downtimes to a
minimum. They used 6 operators
per shift to keep all the mixers
running and they tipped all preweighed
materials from a mezzanine
floor directly into the mixers,
ingredient by ingredient. The mixing
time was uncommonly long at 1
hour, with a poor flowing product
taking longer at 1.5 hours.
After mixing, eight operators were
then required at the ground level to
execute pack-off. During this packoff
time, the mixers are standing
idle and not adding any value. In
addition, the eight operators could
only work on one mixer at a time,
so the other three mixers had to
wait their turn, wasting even more
production time. This made it
impossible to keep the mixers at a
high OEE rate (overall equipment
effectiveness). The production
process was very complex to
manage as there were too many
quality control points and the 14
operators were working in a busy,
dusty environment.
Companies that have found
themselves in a similar situation
have attempted to break up the
long pipework or in-line processing
equipment by using tilting aluminium
totes and/or big bags. They have
continued to use the large ribbon
mixers, but removed the pneumatic
pipework, and used the containers
to collect blended material from the
mixer and deliver it to the packing
lines. This enables the mixer to
go straight into cleaning as soon
at the last bit of powder has been
DAIRY
14 SEPTEMBER 2019