Method and device for removing oxygen from the headspace of a package

Translation of description of equivalent WO 9617775 A1

Method and device for removing oxygen from a package headspace.

An oxygen scavenging method of the headspace of a package filled aseptically, wherein the sterile air atmosphere packaging is filled, is then injected sterile nitrogen with a nozzle disposed directly above the opening of said package at ambient temperature and atmospheric pressure in a sterile air atmosphere and sealed packing between two sealing elements. The invention further relates to the device used for the implementation of this method.

In the field of aseptic filling with certain types of machine, it is not possible to fill a package and seal it without leaving a small volume of gas, called headspace. As normally works in systems with sterile air, this headspace contains about 20% oxygen. The presence of oxygen has a negative effect in the sense that during storage of the product contained in said package, it often happens that the product is sensitive to oxygen, thus leading to a deterioration of its taste and / or of certain ingredients, such as vitamins and minerals. This is unacceptable for the consumer or for reasons of food law. is carried out in this case by replacing just prior to sealing the air with water vapor: a solution in which it is desired to reduce the head space has already been envisaged. The disadvantage of this system however is that the water vapor condenses on cold surfaces: the result is an unacceptable risk of infection for the neutral and weakly acidic products. A second solution is to reduce the headspace with mechanical elements pressing the package, but it is not however not possible to completely eliminate said space. Patent DE 3108817 also relates to a device for removing oxygen from a package headspace. In this device, the nozzle for injecting nitrogen is integral with one of the sealing elements, which decreases the efficiency of the nitrogen inlet, for moving said nozzle and the jet of nitrogen exchange direction. U.S. Patent 4,934,127 and EP 479.037 also relate to devices for removing oxygen from a package headspace. The disadvantage of these devices is that the sealing of the package is done downstream from the nitrogen injection station, that has the effect of leaving leave the amount of nitrogen introduced beforehand.

The object of the present invention is the development of a method for removing oxygen from the headspace of an aseptically filled package efficiently. By eliminating, it is meant to achieve a very low oxygen content in the headspace, ie around 2% and less.

According to the method of the invention, gold. sterile nitrogen injected from the nozzle which is fixed and disposed between the two movable sealing elements.

The packaging used can be of any type, pouvu that its upper part is sealable.

The packaging filler can be any liquid type food area, for example a product: from milk to us of fruit or water, may also contain some ae pieces. Gold. Most preferred

_* especially oxygen sensitive products and weakly acidic comre dietetic products containing vitamins and mineral salts. The goal is to get Long shelf life of products, for which there is no degradation of taste and / or of certain ingredients during storage.

The method is implemented on a line vector industrial manufacture, wherein there is in particular a filling compartment and a scel¬ spinning compartment must be added according to the invention in the sealing compartment an injection step d 'nitrogen.

The two filling compartments and sealing are under a stream of sterile air so as to create turbulent conditions: the nitrogen injection speed is greater than the speed of injection of sterile air. To achieve a headspace having an oxygen content of less than 2%, it is necessary to work with a line by nitrogen flow rate between 100 and 800 1 / min at atmospheric pressure.

The nitrogen injection duration per package is of the order of the second. This rapid nitrogen injection saves the amount of nitrogen and limit the length of the production line. Can both operate with a nitrogen inlet continuously or discontinuously.

It improves the efficiency of removing residual air in the headspace with a specific provision of the arrival of the nitrogen stream: the procedure in this case, with the nitrogen coming from the top under a angle of between 40 and 50 ° relative to the vertical and against the direction of movement of the Current packaging.

The invention further relates to the apparatus usable for implementing the method described above. This device comprises a product filling compartment in a package, a sealing compartment said emDallage with two sealing elements and a conveyor device for conveying the packages into the two compartments, the second compartment comprising a fixed nozzle for injecting nitrogen, the latter being disposed between the movable sealing elements.

The carrier device to an advanced system not to stepper and one arrives at a conventional filling rate to this type of line. It is understood that in this specification, all that is said regarding aseptic filling mode: nitrogen and air are used presténlises.

Is placed in the nitrogen inlet distributor and a nozzle for additional means, such as one or more metal plates to obtain uniform flow to the nozzle outlet.

The nozzle is positioned so that it makes an angle between 40 and 50 ° with the vertical.

It also requires that the nitrogen flow reaches sufficient width to move the well ae residual air headspace: providing an upper nozzle width has the opening width of the emDallage. The following description is made with reference to the drawings wherein:

Fig. 1 is a schematic representation of the device according to the invention, in the nitrogen injection step and

Fig. 2 is a schematic representation to the same device in the sealing step.

The packages arrive one by the carrier device 2 in the direction of flecnes 3 in the compartment that aseptic filling 4 and in compartment ae sealing 5. Sterile air is injected into both said compartments respectively through lines 6 and 7. The product 8 arrives through the filling system 9 and is dosed into the container 1 through the filling nozzle 10. The 5 sealing compartment includes the fixed nozzle 11 for injecting nitrogen, the nitrogen from line 12 and the two sealing members 13,14.

Aseptic filling compartments 4 and sealing 5 have openings 15, 16, 17 allowing passage of the packages 1 on the conveyor device 2.

The operation of the device according to the invention is: Transporter 2 device has an advanced step-by-step system. The package 1 is positioned under the filling nozzle 10, which then delivers the dose 8. The compartment is permanently under sterile air atmosphere. The carrier device then positions other packages under the nozzle 10 and the filled packages arrive in the sealing compartment 5 and pass under the nozzle 11 of the injection of nitrogen. The nitrogen flow rate was 300 1 / min, the sealing compartment being it permanently as sterile air atmosphere. In Fig. 2, we can see the sealing operation with the elements 13 and 14. The carrier device 2 then delivers the packages ready for use or storage.

This gives the invention of packaging that can be stored for at least 6 months without any degradation in quality and taste of the product u. Vitamins and minerals are also preserved. In -l'exemple cited above, we arrive at an oxygen content of 1 * into the head space.