Note: Descriptions are shown in the official language in which they were submitted.
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METHOD FOR SANITIZING UDDERS AND MILKING UNITS
Field of the Invention
The present invention relates generally to the dairy industry and in
particular to a novel method for sanitizing the udders and teats of cows and
other
mammals which provide milk for human consumption. The novel method may also
be used for sanitizing various components of the milking units, such as the
claws
and the liners of the teat cups.
Background of the Invention
One of the most significant problems faced by the dairy industry is the
cleaning and sanitizing of the equipment involved in the process of milking.
The
sanitizing is necessary to ensure not only the health of the consumers who
drink the
milk but also the health of the cows and other mammals who provide the milk.
The
physical environment of cows and other milk-producing mammals is far from
being
clean; they are often covered with mud, insects, agricultural debris and the
like, and
are constantly exposed to a wide variety of bacteria and other pathogens. As a
consequence, the mammals themselves, in particular the udders and the teats,
must
be cleansed and sanitized prior to milking, to minimize the contamination of
the
milk drawn from them and to prevent infection of the mammary gland (mastitis)
by
bacterial contamination. In addition, the equipment used in the milking
process, in
particular the "teat cups" that are attached to the teats and which are part
of standard
pneumaticimechanical automatic milking apparatus must also be properly cleaned
and sanitized, so as to prevent the transfer of bacteria and other pathogens
from one
animal to the next and to prevent contamination of the milk as it is being
conveyed
to storage tanks.
Various methods are known and used in the dairy industry in connection with
the cleansing and sanitizing of the equipment involved in the milking process.
These
include the washing of the udders utilizing streams of water under pressure,
dipping
or spraying the udders and teats with one or more bactericides, and the
flushing and
"back-washing" of the milking apparatus with water, detergents and the like.
However, at least two serious drawbacks have been encountered in the dairy
industry when utilizing the known methods for sanitizing udders and associated
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milking equipment. The first drawback stems from the fact that the various
bactericides that have been certified for use by health authorities have a
long
"contact rime", i. e. they must remain on the udders and other surfaces to
which they
are applied for a minimum of 25 seconds if they are to be effective. The
second
drawback stems from the fact that the bactericides and any other substance
applied
to the udders must be completely washed oil prior to the milking, so as to
prevent
any residues from entering the milk itself. Both the long contact time of the
certified bactericides and the need to wash off the bactericides from the
udders and
the associated milking equipment before each cow is attached to the milking
machine result in a significant lengthening of the actual milking time of an
average
herd of cows (which may well number in the hundreds). For many dairy farmers,
whose margin of profit is very small, this lengthening of the milking process
is
economically unacceptable. As a consequence, many dairy farmers do not
sanitize
their caws prior to milking, and merely rinse the udders with water. For the
same
reason, many dairy farmers do not sanitize the claws, teat cups and teat cup
liners
which come into contact with the cows, between the milking of one cow and
another, and do so only after the whole herd has been milked. This practise
significantly increases the probabilities that mastitis (infection of the
mammary
glands) or. other diseases may be spread from one animal to another.
US Patent 5,211,961 describes a gel composition for cleaning and sanitizing
the teats and udder of an agricultural animal for machine milking. In
accordance
with this patent, residual surface water, which is a source of milk
contamination and
mastitis, is eliminated from the teats and udder by use of the gel
composition. The
gel composition comprises water, a germicide added to the water in
concentration
sufficient to kill environmental bacteria which cause mastitis, an aqueous
gelling
agent, a soap or a detergent, and a skin softener. The composition is applied
to the
teats and acts as a cleansing and sanitizing agent; however, prior to milking,
the gel
must be wiped from the teats and the teats thoroughly cleaned prior to
attachment to
the milking machine.
US Patent 5,567,444 (to Ecolab) describes a method for cleaning and
sanitizing soiled solid surfaces, especially in-place process facilities. The
method
involves contacting the soiled surfaces with an aqueous ozone cleaning
composition
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' WO 99/38374 PCT/IL99/00029
having a pH of at least 8 and comprising an effective ozone composition
sufficient
to produce an oxidation-reduction potential of at least +SSOmV with respect to
an
Ag/Agcl reference electrode, and then circulating an aqueous sanitizing
composition
containing hydrogen peroxide, a Cl-Coo peroxyaliphatic carboxylic acid or a
mixture
thereof sufficient to reduce the oxidation-reduction potential below about
+400 mV.
One of the process facilities stated to be suitable for the use of such a
method is a
milk-line dairy.
Summary of the Invention
The present invention provides a novel method for sanitizing the teats and
t 0 udders of milk-producing mammals, as well as for sanitizing equipment
utilized in
the milking process, which overcomes the drawbacks inherent in the methods
utilized today in the dairy industry. In particular, the present invention
enables the
sanitizing of the teats and udders, as well as the sanitizing of the milking
equipment
which comes into contact with the bodies of the mammals being milked, without
the
need to substantially interrupt the milking process so as to carry out the
sanitizing
process. The "contact time" is very brief and there are no traces or residues
of
potentially harmful bactericides. The method is particularly beneficial in
enabling
the sanitizing process to be carried out between the attachment of each cow to
the
milking machine, thereby assuring a much greater level of sanitizing than is
obtained
using conventional techniques. In addition, when using the present invention,
it is
possible to cut back significantly on the amount of water and detergents that
need to
be used in the cleansing and back-flushing of the milk line, such that the
present
invention is also economically advantageous for dairy farmers.
There is therefore provided in accordance with a preferred embodiment of the
present invention a method for sanitizing the teats and udders of milk-
producing
mammals comprising the steps of (a) rinsing the teats and udders with water;
and
(b) applying a solution of ozonated water to the teats and udders. In
accordance with
a preferred embodiment of the invention, the ozonated water is applied by
dipping
the teats and udders in a solution of ozonated water or by the spraying of the
teats
and udders with a solution of ozonated water. Further in accordance with a
preferred
embodiment of the invention, the effective concentration of ozone in the
ozonated
water is between the range of 0.01 mg and 5 mg ozone per liter of water;
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altennatively, between the range of 0.05 mg and 1 mg ozone per liter of water.
In
accordance with a preferred embodiment of the invention, the teats and udders
of
each mammal in the herd of mammals being milked is sanitized with the ozonated
water immediately prior to the attachment of the mammal to the milking
machine,
and optionally also immediately after detachment from the milking machine.
As more fully described herein, the present invention also encompasses the use
of ozonated water for the sanitizing of teats and udders of milk-producing
mammals.
In accordance with a preferred embodiment of the invention, the ozonated water
is
applied by dipping the teats and udders in a solution of ozonated water or by
the
spraying of the teats and udders with a solution of ozonated water. Further in
accordance with a preferred embodiment of the invention, the elective
concentration of ozone in the ozonated water is between the range of 0.01 mg
and
5 mg ozone per liter of water; alternatively, between the range of O.OS mg and
1 mg
ozone per liter of water. In accordance with a preferred embodiment of the
invention, the teats and udders of each mammal in the herd of mammals being
milked is sanitized with the ozonated water immediately prior to the
attachment of
the mammal to the milking machine, and optionally also immediately after
detachment from the milking machine.
The present invention also provides a simple, effective method for preventing
mastitis and other diseases of the mammary glands of milk-producing mammals,
the
method comprising the steps of (a) rinsing the mammary glands with water; and
(b) applying a solution of ozonated water to the mammary glands. In accordance
with a preferred embodiment of the invention, the ozonated water is applied by
dipping the teats and udders in a solution of ozonated water or by the
spraying of the
teats and udders with a solution of ozonated water. Further in accordance with
a
preferred embodiment of the invention, the effective concentration of ozone in
the
ozonated water is between the range of 0.01 mg and S mg ozone per liter of
water;
alternatively, between the range of 0.05 mg and 1 mg ozone per liter of water.
In
accordance with a preferred embodiment of the invention, the teats and udders
of
each mammal in the herd of mammals being milked are rinsed with the ozonated
water immediately prior to the attachment of the mammal to the milking
machine,
and optionally also immediately after detachment from the milking machine.
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The present invention also provides an efficient method for sanitizing the
teat
cups andlor other components of a milking machine, the method comprising
flushing the teat cups and/or other components with ozonated water. In
accordance
with a preferred embodiment of the invention the concentration of ozone in the
water is between the range of 0.01 mg and S mg ozone per liter of water,
alternatively, between the range of O.OS mg and 1 mg ozone per liter of water.
Detailed Description of the Invention
The present invention utilizes the knowledge that has been developed
concerning the powerful effect of ozone as an oxidizer and disinfectant, and
applies
this knowledge to the dairy industry. Ozone (CAS No. 10028-15-6) is a
naturally
occurring triatomic form of oxygen. It is a gas at both ambient and
refrigerated
temperatures. Ozone is produced naturally by the effect of solar ultraviolet
radiation
on atmospheric oxygen. The stable bonds of an oxygen molecule are cleaved into
two short-lived oxygen atoms which react almost immediately with another
oxygen
1 S molecule to form ozone. At ground level, ozone is produced when lightning
is
discharged through the atmosphere, and this is the cause of the familiar,
fresh, clean
smell of air following a thunderstorm.
Commercially, ozone has been in use for well over a hundred years in
connection with the treatment of drinking water. As of 1.993, there were more
than
2,S00 large scale water-treatment installations which utilized ozone as a
means for
purifying and treating water. Ozone is also used in the treatment of swimming-
pool
water and in the treatment of odors from industrial processes and municipal
secondary effluents. Industrial high quality water supplies also are often
treated with
ozone, for example in breweries and in the production of soft-drinks.
2S Ozone is a powerful oxidant and as such is very useful as a disinfectant.
It is
considered to be the most eff-lcient disinfecting agent for water, being more
eiflcient
than substances such as chlorine dioxide, hypochlorous acid, hypochlorite ion,
dichloramine, and monochloramine.
Ozone is also a powerful bactericide. It attacks the bacterial membrane at the
glycoproteins and glycolipids, or at certain amino acids such ~as tryptophan.
It also
acts on the sulfhydryl groups of certain enzymes, resulting in the disruption
of
normal cellular enzymatic activity. Bacterial death is rapid and has been
attributed to
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changes in cellular permeability in consequence of the high oxidant
concentration.
Ozone further acts on the nuclear material of the bacterial cell by modifying
the
purine and the pyrimidine bases of nucleic acids. Ozone has been found to be
effective against Gram-positive (including spore-formers) and Gram-negative
bacteria, viruses, and protozoa.
Ozone has many applications in the food industry. It is used to increase the
yield of certain crops, to protect raw agricultural commodities during storage
and
transit, and to sanitize water used for washing food equipment, foods, and
packaging
materials.
Ozonation is classified by the United States Food and Drug Administration
(FDA) as Generally Recognized As Safe (GRAS) for the treatment of bottled
drinking water, when used in accordance with good manufacturing practices. The
approved maximum residual level at the time of bottling is 0.4 mg of ozone per
liter
of bottled water. The use of gaseous ozone up to 0.1 ppm in meat-aging coolers
has
also been accepted by FDA. In 1997, an Expert Panel Report provided an
unequivocal declaration of GRAS status for ozone for use in food processing.
One of the most important characteristics of ozone that make it attractive for
use as a sanitizes in the food industry and elsewhere is that it does not
leave any
residues, since it does not remain in water for a very long period of time. As
a
consequence, ozonation may be considered to be a process rather than a food
additive, with no safety concerns about possible consumption of residual ozone
in
food products. Any by products that ozone may produce in the treatment of
foodstuffs are similar to normal oxidation products, and thus are not likely
to have
deleterious health effects.
The inventors have discovered that ozonated water can also be used both
efficiently and effectively as a sanitizes for the dairy industry, in
particular in the
sanitizing of the teats and udders of cows and other milk-producing mammals,
and
the sanitizing of the milking apparatus itself. Ozonated water, at a
concentration of
up to 5 mg/liter, i.s very effective in destroying the bacteria and other
pathogens that
are found on the udders of milk-producing mammals, and therefore is a highly
effective sanitizes. The bactericide effect of ozonated water is almost
immediate,
such that it may be applied to the udders and teats immediately prior to the
milking,
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thereby assuring a very high level of sanitizing, without any concomitant
lengthening
of the milking process. In addition, as a consequence of the fact that
ozonated water
does not leave any undesirable residues, there is no basis for concern lest
any artifact
or other by-product of the sanitizing by ozonated water will contaminate the
milk. In
principle, there is no. need to remove the ozonated water after it has been
applied to
the teats and udders; however, a simple rinsing with plain water may be done,
if this
is found to be desirable. Furthermore, because it is possible to apply the
ozonated
water to the udders with relative ease and speed, it is possible to do the
sanitizing
before each and every cow is attached to the milking machine, thereby
achieving a
degree of sanitizing that is not obtainable currently by conventional methods.
Optionally, so as to provide an additional degree of sanitizing, the udders
and teats
of each mammal may be rinsed again with ozonated water, after the conclusion
of
the milking and the separation from the teat cups.
The present invention is particularly advantageous in that it does not
necessitate any substantive alteration of the millcing process or of the
milking
machines currently in use. There are many commercially available ozone
generators,
such as Azcozon VMUS-4, manufactured by Azco Industries Linuted (Surrey,
British Columbia, Canada), and these may readily be adapted for use in the
implementation of the present invention. The ozone generator may simply be
attached by an injector in a conventional manner to the source of water that
is used
both for the cleansing of the mammals and the cleansing of the milking
apparatus.
Prior to the attachment of each mammal to the teat cups, the udders and teats
of the
mammal are first thoroughly washed with plain water, and then thoroughly
washed
with ozonated water, with the ozonated water having a concentration of ozone
sufficient to be an effective bactericide. A minimum concentration of 0_01 mp
ozone per liter of water has been found to be necessary, and a concentration
of up to
5 mg/liter is more than su~cient; preferably, the concentration is between
0.05 mg
and 1 mg ozone per liter of water. The pre-milking washing and sanitizing may
be
done in any conventional manner, in the holding area, the sprinkler pen of the
millcing parlor or in the milking parlor itself, either by dipping the udder
and teats in
the ozonated water or by spraying the ozonated water on the teats and udders.
In
parallel, the teat cups themselves, including the liners, pipes and other
hardware
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associated with them are also thoroughly flushed with the ozonated water,
thereby
assuring that the equipment which comes into immediate contact with the
mammals
is thoroughly sanitized
Ozonated water, in accordance with the invention, as described above, may
be used effectively either in addition to or in place of other means of
sanitizing
currently used in the dairy industry. Because ozonated water is such an
efficient
bactericide, the use of ozonated water in accordance with the invention is
also
beneficial in the prevention of mastitis, and in preventing the spread of
disease from
one animal to the other, which often occurs today due to the fact that the
teat cups
are not sanitized after being use by each animal.
Ozonated water, in accordance with the invention, may also be used most
effectively in sanitizing other component parts of the milking ap~ratus. Thus,
after
the whole herd has been milked and the collected milk has been emptied from
the
collection tank, ozonated water can be used to flush the whole system
(including the
bulk tank), preferably after a prior cleaning of the system with a detergent,
as is
conventionally done. And because ozonated water is such an efficient
bactericide,
when using ozonated water in accordance with the invention, significantly less
water and detergents are needed for the proper cleansing and back-flushing of
the
milk line. Thus, the present invention not only provides a simple and e~cient
method of sanitizing, but it also provides significant economic benefits for
the dairy
industry.
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