METHOD FOR STERILIZING A PRODUCT THAT IS PACKAGED IN A PACKAGING MATERIAL

PROCEDE POUR STERILISER UN PRODUIT CONDITIONNE DANS UN EMBALLAGE

English Abstract

Disclosed are a method and a device for sterilizing a product that is packaged
in a packaging material. The package (1) comprising the product and the
packaging material is subjected to thermal treatment at a defined temperature
for a given period of time. The following steps are carried out in order to
protect packages (1) which would generally not resist the conditions
prevailing in an autoclave: - at least one package (1) is introduced into a
protective covering (2 ); - the space between the protecting covering (2 ) and
the package (1) is evacuated; - the protective covering (2) is sealed; and -
the protective covering (2 ) and the package (1) are autoclaved in an
autoclave. The corresponding inventive device comprises a repackaging unit, an
evacuating unit, an autoclaving unit, and an optional unpacking unit, each of
which tops the filling machine.

French Abstract

L'invention concerne un procédé et un dispositif pour stériliser un produit conditionné dans un emballage, le paquet (1) constitué par le produit et l'emballage étant soumis à un traitement thermique à une température donnée pendant une durée déterminée. L'invention vise à protéger les paquets (1) qui, normalement ne résisteraient pas aux conditions régnant dans un autoclave. A cet effet, le procédé de l'invention comprend les opérations suivantes: - mettre au moins un paquet (1) dans une enveloppe de protection (2'), - faire le vide dans l'espace entre l'enveloppe de protection (2') et le paquet (1), - fermer l'enveloppe de protection (2') et passer l'enveloppe de protection (2') et le paquet (1) à l'autoclave. La présente invention porte également sur un dispositif correspondant qui comprend, en aval de la machine de remplissage, une unité de remballage, une unité de production du vide, une unité autoclave et éventuellement une unité de déballage.

Claims

CLAIMS
1. A method for the sterilisation of a product packaged
in a packing, where the package comprising the
product and the packing is subjected to a heat
treatment at a specific temperature and for a
specific duration, characterized by the following
steps:
- Introduction of at least one package into a
protective casing,
- Evacuation of the space between the protective
casing and the package,
- Closing of the protective casing,
- Autoclaving of the protective casing and package
in an autoclave, and
- Removing of protective casing from the package
after the autoclaving.
2. A method for the sterilization of a product packaged
in a packing, where the package comprising the
product and the packing is subjected to a heat
treatment at a specific temperature and for a
specific duration, characterized by the following
steps:

-2-
- Introduction of at least one package into a
protective casing,
- Closing of the protective casing,
- Evacuation of the space between protective casing
and package, and
- Autoclaving of the protective casing and package
in an autoclave.
3. The method according to claim 1 or 2, characterized
by a separate protective casing for each package.
4. The method according to claim 1 or 2, characterized
in that a protection system comprising a protective
casing and a base plate can receive multiple
packages.
5. Apparatus for performing the method according to one
of the claims 1 to 4, characterized by one of each
of the following units downstream of the filling
machine, namely a repackaging unit, an evacuation
unit, an autoclave unit, and, if required, an
unpacking unit and a protection system comprising at
least one base plate (4, 4', 4'') for the reception
of multiple packages (1) and at least one protective
casing (2, 2') covering the packages (1), wherein
the space between base plate (4, 4', 4'') and
protective casing (2, 2') can be evacuated.

-3-
6. Apparatus according to claim 5, characterized in
that the base plate (4, 4', 4'') is a metal plate.
7. Apparatus according to claim 5 or 6, characterized
in that the base plate is essentially positioned
horizontally, and the packages are placed on the top
of the base plate at a distance to each other.
8. Apparatus according to claim 5 or 6, characterized
in that the base plate (4, 4', 4'') has multiple
openings (6) for the reception of packages (1), and
the packages (1) are held in the base plate (4, 4',
4'') by means of the at least one protective casing
(2, 2').
9. Apparatus according to claim 8, characterized in
that the base plate (4') in the protection system is
essentially positioned horizontally.
10. Apparatus according to claim 8, characterized in
that the base plate (4'') in the protection system
is essentially positioned vertically.
11. Apparatus according to claim 5 to 10, characterized
in that each protective casing (2, 2') consists of a
flexible foil.
12. Apparatus according to claim 11, characterized in
that the foil is a plastic foil comprising a barrier
layer.

-4-
13. Apparatus according to claim 11 or 12, characterized
in that the protective casing (2, 2') consists of
polypropylene (PP).
14. Apparatus according to claim 11 or 12, characterized
in that the protective casing (2, 2') consists of
polyethylene terephtalate (PETP).
15. Apparatus according to claim 11 or 12, characterized
in that the protective casing (2, 2') consists of a
thin duroplastic foil.
16. Apparatus according to claim 11, characterized in
that the protective casing (2, 2') consists of
rubber.
17. Apparatus according to one of the claims 11 to 16,
characterized in that the protective casing (2, 2')
consists of a shrinking foil.
18. Apparatus according to one of the claims 11 to 17,
characterized in that the protective casing (2, 2')
has a metallic coating.

Description

CA 02475130 2004-08-04
TH/bs 020101W0
30. Juli 2004
METROD FOR THE STERILISATION OF A PRODUCT
PACKAQED IN A PACKINQ
The invention relates to a method and an apparatus to
sterilize a product packaged in a packing, where the
package comprising the product and the packing is
subjected to a heat treatment at a specific temperature
and for a specific duration.
It has been known for a long time to subject products
packaged in portions such as food to a so-called
autoclave method. Cans, for example, that have been
filled with a food product, are hereby exposed to a
specific temperature in an autoclave for a specific
duration to safely kill the germs in the package. Cans
have particularly proven themselves for this purpose as
they are insensitive to the conditions in the autoclave
(high temperature, high humidity).
If, however, food products, or other products that
require sterilization, are not packaged in cans but in a
different packing, the packing must first be sterilized -
requiring a relatively high amount of additional
efforts -, then the product must be filled into the
packing and eventually the packing must be closed
aseptically.
The carton or plastic composite packages axe also able to
hold products such as milk or mashed vegetables for a
longer period of time.
2~~bs ozoloiwo

CA 02475130 2004-08-04
- 2 -
DE-A-36 26 616 describes a method for sterilizing a
product in a bag, wherein product and bag are being
sterilized in an autoclave. First, the bag is put into a
protecting casing, then the protective casing is
evacuated and closed and, finally, the closed bag packed
in the protective casing is autoclave. Each bag has a
single protective casing which remains after the
autoclaving at the bag. In consequence, the protective
casing is an integral part of the bag to be sterilized.
EP-A1-0 982 236 also describes a method for sterilizing
products protectively packaged, wherein each product is
placed within a packaging tray including a nest area for
carrying the product is put in a protective bag and
finally vacuum sealed. Now, product and bag are packed
into a package capable of autoclaving and sterilized in
an autoclave consecutively.
The object of the invention is to enhance and develop
this method and the corresponding apparatus to sterilize
a package in order to also allow the use of packages that
would usually not be able to withstand the conditions in
an autoclave.
In regards to the method, the object is solved by means
of the following steps:
- Introduction of at least one package into a protective
casing,
- Evacuation of the apace between protective casing and
package,
TH/be 020101W0

CA 02475130 2004-08-04
- 3 -
- Closing of the protective casing hermetically,
- Autoclaving of the protective casing and package in an
autoclave, and
- Removing of protective casing from the package after
the autoclaving.
Alternatively, the object is solved by the steps of
following sequence:
- Introduction of at least one package into a
protective casing,
- Closing of the protective casing,
- Evacuation of the space between protective casing and
package, and
- Autoclaving of the protective casing and gackage in
an autoclave.
In regards to the apparatus, the object is solved with
one of each of the following units downstream of the
filling unit: one repackaging unit, one evacuation unit,
one autoclave unit and, if required, one unpacking unit,
and a protection system comprising at least one base
plate for the reception of multiple packages and at least
one protective casing covering the packages, wherein the
space between base plate and protective casing can be
evacuated.
TH/be 020101W0

CA 02475130 2004-08-04
q _
According to the invention, the repackaged product to be
sterilized, such as a carton composite package filled
with food products to be sterilized, and sensitive to
water, is protected from the penetration of water and
gas. The protective casing prevents any negative
impairment of the carton composite package due to the
autoclave water. The additional packing of the protective
casing ensures that neither water nor gas can penetrate
into the packing material of the package. This ensures
that neither the shape of the package nor the quality of
the product is impaired.
With the invention less complex and therefore cheaper
composite materials can be used. It is also possible to
use printing colors which are more susceptible to water
(cheaper?. Moreover, higher temperatures can be achieved
within the autoclaves and therefore, shorter process
times, the quality in taste of food can be increased.
~/bs ozoioiwo

CA 02475130 2004-08-04
- 6 -
Following, the invention is described in more detail by
means of a drawing that only shows the preferred
embodiments. In the drawing shows
Fig. 1 in perspective, a package to be sterilized, in a
protective casing that has not been closed yet,
Fig. 2 the package from fig. 1, in a closed protective
casing after the evacuation,
Fig. 3A schematically, multiple packages to be
sterilized, on a base plate,
Fig. 3B the packages to be sterilized from fig. 3A, in a
protective casing before the evacuation,
Fig. 3C the packages to be sterilized from fig. 3B,
after the evacuation,
Fig. 4A another embodiment of the protection system
according to the invention, schematically in
cross-section,
Fig. 4B the protection system from fig. 4A,
schematically, in top view,
Fig. 4C the protection system from fig. 4A,
schematically, containing the packages to be
sterilized, after the evacuation,
Fig. 5A another embodiment of the protection system
according to the invention before the
evacuation, schematically in cross-section and,
TH/ba 02D1O1W0

CA 02475130 2004-08-04
7 _
Fig. 5B the protection system from fig. 5A after the
evacuation, schematically side-view.
Fig. 1 and 2 show a package 1 to be sterilized, in this
preferred embodiment, a rectangular carton / plastic
composite package, that is being prepared for the
autoclave process in a single protective casing 2. To
achieve this, the protective casing 2, as shown in fig.
2, is closed, and evacuated by means of a line 3
comprising a valve (not shown). The protected package 1
can now be autoclaved without damaging its form or
content, the protective casing 2 can then be removed from
the package 1, or remain wrapped around the package 1 to
be removed by the reseller or end consumer.
Fig. 3A and 3C show an embodiment of the protection
system according to the invention, wherein a base plate 4
and at least one protective casing 2' are aligned in such
a way that multiple packages 3 to be sterilized are held
within this protection system. In this embodiment, the
base plate 4 consists of material that transfers heat
well, such as metal, to ensure sufficient heat
introduction / exchange from below to the packages 1
during the autoclave treatment. The protective casing 2'
and the base plate 4 are connected with each other in a
pressure-tight manner by at least one closure 5, that
might, for example, go all around the casing. The
combination of protective casing 2' and base plate 4
creates sufficient counterpressure, so that the packages
are not deformed or damaged during the autoclaving. Fig.
3C shows, in a dashed line, that such a protection system
can also have several lines 3 for evacuation.
TH/bs D2D1o1wo

CA 02475130 2004-08-04
_ g _
An alternative embodiment of the protection system
according to the invention is shown in fig. 4 and 5. The
base plate 4' provides multiple openings 6 of about the
size of a package cross-section. In fig. 4, the base
plate 4' is positioned horizontally and the protective
casing 2' is led through the openings 6, creating
separate, bag-like chambers 7 for the reception of the
packages 1. Fig. 4C shows that in this embodiment, the
packages I are no longer in contact with the base plate
4' after the evacuation. In addition, a cover 8 with
noses 9 of about the same size as the openings 6, is put
on the base plate 4' from above.
Finally, fig. 5A and 5B show an additional embodiment of
the invention, where a vertically positioned base plate
4 " provides openings 6 for the reception of the packages
1, and a protective casing 2 " , enclosing the complete
base plate 4 ", ensures the sealing of the packages
against the environment, as well as their secure hold in
the base plate 4 " . This embodiment provides itself as a
preferred solution since the closing, evacuation,
opening, and removal of the protective casing is
particularly easy and fast.
TH/bs 020101W0

Representative Drawing