Agriculture Reference
In-Depth Information
fats and oils may be temporarily emulsified by the heat
and may pass unhindered through the grease trap prior
to the effluent system.
The biodegradability of the detergents and disinfect-
ants themselves is also important, but not because they
themselves contribute greatly to the total COD/BOD of
the plant effluent. Their contribution, in comparison to
that of the food process effluent and residual soil car-
ried away by cleaning, is minor. There are some sur-
factants, previously common in many detergents and
disinfectants, which are now known to partly biode-
grade to slightly simpler, but more environmentally
damaging, molecules. One group in particular, the
alkylphenol ethoxylates (APEOs), is believed to have
oestrogenic effects in river waters, possibly affecting
the reproduction of aquatic organisms. They are
banned in detergent and disinfectant formulations, as
are other non-biodegradable surfactants (Council
Regulation (EC) No 658/2004). The chemical supplier
should be asked to supply chemicals, backed up by spe-
cific product data, which conform to the latest EU envi-
ronmental regulations.
Odour control
may be particularly important if the
factory is situated close to residential areas. Odour may
arise from the effluent plant itself, if aeration is inade-
quate, loading is excessive (see earlier) and anaerobic
bacteria are flourishing. Such problems may be helped
by improving aeration and reducing the COD/BOD
loading to the plant. Other methods to assist the break-
down of proteins and other organics include the addition
of
enzyme
preparations in the effluent stream as it leaves
the plant or even in the factory drain system. The
enzymes begin the biodegradation process early and
assist the main treatment plant in handling its burden.
Other odours may arise from exhausts from rendering
plants and from waste skips. The most common chemi-
cal treatments used here involve 'scrubbing' the exhaust
gases with fine showers containing oxidising disinfect-
ants such as chlorine dioxide or peracetic acid or spray-
ing the disinfectant into the skips themselves. These
chemicals act to oxidise and break down the malodorous
molecules (which are usually relatively small volatile
molecules containing sulphur). An alternative approach
is to use essential-oil-based sprays to destroy the mole-
cules. Attempting to mask the malodour with a per-
fumed agent is usually not successful.
prosper is the need to keep its reputation intact, major
retail customers happy and consumers confident in the
brand and quality of its products. Particularly when food
safety issues come to light and are taken up by the media,
the damage can be to individual businesses or a whole
food industry sector; it is vital for companies to maintain
explicitly the highest hygiene standards. Profit margins
are often very tight and cost pressures on one side, versus
legislative and quality pressures on the other, contrive to
make the meat plant hygienist's job more demanding
and the cost of failure higher. It cannot be that we drive
for a good and consistent hygiene performance at any
cost; to be clear, that cost is in essence financial, but it
breaks down to resources such as people, plant down-
time, water and energy. That would not be prudent busi-
ness practice, but importantly, it is also not a sustainable
approach considering the present and future availability
and increasing cost of water and energy. The achieve-
ment of a consistently good hygiene performance at a
sustainable cost, in the broadest terms, that will always
come from a professionally managed and well-controlled
operation.
All persons involved in plant hygiene, from top man-
agement down, must appreciate that plant sanitation is a
vital, skilled and multidiscipline task. It requires consist-
ently effective management to ensure that the general
methods and the fine details are kept under constant
attention and that potential problems are highlighted
and dealt with early enough to avoid them becoming real
and damaging. Some companies choose to outsource
their plant sanitation to specialist contract cleaners. If
professionally resourced, trained and managed, contract
cleaners are an effective solution.
However, some food companies prefer to keep this
pre-requisite programme within the remit of their fac-
tory management to ensure more direct control,
accountability and timely corrective action. Whatever
choice is made, the fact remains that the food plant
management must maintain a close interest in and
understanding of plant hygiene and sanitation. Suppliers
of hygiene equipment and materials, if selected for their
quality and professionalism, can also be a major asset to
the food plant hygiene manager, but the most important
support that he or she can have is that of the senior
management team in giving hygiene a status equal to
that of production.
Note
1 COP is used throughout this text to mean Cleaning Open Plant. It
is not a globally standardised abbreviation. It is used in the United
States for Cleaning Out of Place where equipment is dismantled
and moved to a cleaning room, and also Open Plant Cleaning
(OPC) is in use in Europe.
Conclusion
Plant cleaning and disinfection have deservedly earned a
much higher profile than they had previously attained.
While legislation has provided some of the impetus, the
real driver for any food processing operation wishing to
