A PROCESS AND A DEVICE FOR HEADSPACE FOAMING OF CONTAINERS FILLED WITH CARBONATED BEVERAGES

Abstract: The invention relates to a process for the foaming of the headspace of containers filled with carbonated beverages, wherein, after the filling of the beverages into the containers, the containers are transferred to a foaming means, in which an electromagnetic beam, preferably a laser beam, is irradiated in a controlled way into the headspace of the container which is not filled with the beverage, whereby, due to the resultant foaming, the gas volume in the headspace is displaced from it, and the containers are subsequently sealed, as well as to a device for carrying out the process.

Description: A Process and a Device for Headspace Foaming of Containers Filled with Carbonated Beverages The invention relates to a process for headspace foaming of containers filled with carbonated beverages, in which the beverage is foamed in the container after filling so that the volume previously contained in the headspace is displaced from it due to the ascending foam, and a device for carrying out this process. In bottling plants, beverages are filled into containers in such a way that a residual gas volume remains in the headspace of the containers. This residual voiume is at first filled with carbon dioxide in the case of beverages containing C0 . Since the containers are exposed to ambient air during transfer form the bottling station to the sealing station, there is a risk of oxygen entering the headspace during this transfer, which promotes germ formation in such beverages and thus greatly reduces their storage stability For the afore-mentioned reason, beverages are conventionally foamed during transfer from the bottling station to the sealing station by introducing a gaseous or liquid medium into the headspace onto the surface of the beverage so that the resultant foam expels the gas volume, and thus also the oxygen that has entered, from the headspace. Thus, the oxygen content in the headspace will be reduced at the moment the container is sealed One example of such a foaming device is disclosed in German Utility Model No. 91 16 8 1 5 TJ 1 A jet of liquid, here in particular water, is introduced into the headspace of the filled containers at a pressure of 40 bar by means of the device described therein The pulse of the water jet can be regulated It is in particular disadvantageous in such process and devices according to the prior art that after the high-pressure water injection the beverage foam has relatively large pores so that, despite large overfoam volumes (2 to 5 ml/container), the average oxygen values that can be achieved in the headspace are not better than 0 01 8 to 0 12 mg per liter The disadvantageously large overfoaming results in a high waste water pollutant load and thus substantial liquid waste disposal costs; also, the large overfoam volumes are equivalent to net beverages losses which, of course, are expensive per se A further main disadvantage of this known foaming process resides in the fact that water, and thus foreign media, is injected into the beverage, thereby diluting it There is danger of germs being injected into the beverage together with the water, while, to avoid this danger, special equipment for preparing germ-free water must be provided The object of the present invention is to create a method and a device for headspace foaming of containers filled with carbonated beverages, which overcome the aforementioned disadvantages of the prior art. In particular, the invention is intended to achieve a good storage stability of the contained beverages and very low foaming losses This object is achieved by a process and a device according to the independent claims The advantage of foaming the beverage according to the invention is first that the foam ascending from electromagnetic beam foaming has much finer pores than, for instance, foam resulting from water injection, and thus becomes substantially more gas-tight The amount of oxygen remaining in the headspace after foaming with an electromagnetic beam is very low. and in a range that conventional high-pressure injection systems with comparable overfoaming losses cannot even approach Another advantage i s that the microporous foam arising from the irradiation with a controlled electromagnetic beam can be regulated very well with regard to the resultant foam quantity and therefore foaming losses can be minimized Thus, the overfoam volumes, which are expensive and waste-water polluting per se, can be greatly reduced A further advantage of the foaming according to the invention resides in the fact that special plant technologies for preparing germ-free water are no ionger required since, as a matter of course, water is not used as a foaming agent As a further result of the fact that the introduction of water can be dispensed with is that the beverage no longer experience dilution or contamination with residual germs in the water Advantageous embodiments of the invention are described by means of the subclaims The electromagnetic beam may be, for example a micro wave beam or the like According to e preferred embodiment of the invention, the electromagnetic beam comprises a laser beam According to a preferred embodiment of the present invention, the containers pass along a bottling conveyor, a transfer conveyor and a sealing conveyor, with the point of foaming by means of laser irradiation being located immediately upstream of the point sealing of the containers According to such a development, the foaming of the beverage is carried out shortly before the sealing of the containers, i e there is little time for the oxygen-containing ambient air to enter the headspace after the foam has displaced the gas therein In accordance with one embodiment of the present invention the laser beam is radiated into the headspace in a pulsed fashion, while it may preferably be triggered by a triggering means such as an ultrasonic switch or a light barrier at a triggering rate adapted to the speed of the containers that pass through As an alternative to triggering by external triggering means, the laser beam may be pulsed per se However, the laser beam may, alternatively, also be radiated into the headspace in a continuous fashion The laser beam radiated onto the surface of the beverage may be adjusted in its intensity, pulse shape, length and/orfrequency according to the requirements of the specific application According to a further embodiment of the invention, the level of foam in the headspace is measured or detected, respectively, by measuring means and the intensity, pulse shape, lenght and or frequency are adjusted dependent on the detected level By means of controlling devices as usually employed in laser technology the following parameters for the laser radiation may be set for a preferred embodiment of the invention The average power of the laser beam irradiated onto the surface of the beverage may be adjusted in the range of about 10 to 20000 W, the frequency of the laser beam may be adjusted in the range of about 5 to about 2000 Hz and the shutter opening time should be in the range of 5 ms to 2000 ms The foaming of the beverage is induced by the energy of the laser beam Since different beverages also foam differently, the power of the laser beam irradiated into the headspace can in each case be adjusted so accurately that foaming losses are minimized while, at the same time, the greatest possible amount of oxygen is expelled Advantageously, the vicinity of the laser beam radiation point may be surrounded by a haze of an inert gas, provided by a corresponding apparatus in order to avoid the entry of ambient air into the headspace The device according to the invention preferably has a laser beam emitter comprising a C0 2 laser with a maximum performance of 10 to 20000 W, a duty cycle of 5 to 100%, an optical guiding system for the laser beam, and a focusing means with a lens having a diameter of about 3 ,81 cm ( 1 , 5 in ) and focal point diameter of 300 to 500 μm The invention is explained in the following referring to the appended Figures Fig. 1 shows an elevation of a device according to the invention for headspace inertization. Fig. 2 shows a detail of Fig 1 , and Fig. 3 shows a top view of a headspace inertization means according to the invention and its arrangement with respect to a bottling conveyor, a transfer conveyor and a sealing conveyer for containers, here bottles Fig 1 shows an elevation of an embodiment of a device according to the invention for headspace inertization The foaming means of this device is designated in general with the reference numeral 10 It comprises a C0 2 laser 1 5 which is firmly anchored to the floor next to a transfer conveyor 33 indicated in dash-dotted lines The transfer conveyor 33 conveys containers 1 8, here bottles, already filled with beverage from a bottling conveyor 3 1 to a sealing conveyor 32 (cf Fig 3 ) The C0 2 laser 1 5 provides a laser beam which is directed into an optical guiding system 16 for the laser beam This system 16 is designed as an arm spanning the distance between the C0 2 laser 1 5 , the focus means 17 being placed directly above the mouth of the bottle 1 8 to be processed The laser beam irradiated onto the surface of the beverage has a power of about 1 0 to about 20000 W, the frequency of the laser beam being adjusted to about 5 to about 2000 Hz, and the shutter opening time being about 5 ms to 2000 ms The employed C0 2 laser shows an average performance of about 10 to about 20000 W and has a duty cycle of about 5 to 1 00% The above variable parameter are set by known control devices for laser beam technology and adjusted in such a way that, in any case, a suitable laser beam with a predetermined power is injected for a specific type of beverage with a predetermined carbonization and/or a predetermined CO 2 content, which effects a foaming in the beverage, but does not result in high foaming losses Thus, foaming is induced in a proportional relationship with the power of the laser beam In the optimum case, the laser beam is radiated onto a black surface The foaming of the beverage by a laser results in a highly microporous foam which displaces the gas volume contained in the bottle 1 8 up to then due to its ascension in the headspace of the containers 18 Because of its microporosity, the resultant foam is highly gas-tight and effects a type of plug flow in the container neck Therefore only a very small amount of the original gas volume remains in the headspace, the gas tightness of the microporous foam alone prevents air from the environment from entering the headspace As a result of this process, the oxygen content in the headspace is at a very low value when the containers 18 are sealed, a result which conventional high pressure water injections in which large-pore foam is formed can not achieve With such a small amount of oxygen in the headspace, the risk of germ formation is minimized The storage stability of the filled beverage is greatly improved Due to the exact adjustability of the parameters of the laser beam, an exactly controllable foaming takes place, and overfoaming losses are largely prevented so that high pollutant loads in the waste water can also be prevented In Fig 2 the focus means 1 7 is shown It may be seen that the lens center is positioned at a short distance directly above the center of the bottle mouth such that the laser beam emitted therefrom directly hits the surface of the beverage without being deflected by any portion of the bottle neck. Fig. 2 further shows how the vicinity of the bottle mouth may be surrounded with a haze of gaseous nitrogen (GAN). Two streams of gaseous nitrogen are employed, namely one annular vertical stream 21 which may be supplied by an annular nozzle 20 surrounding the focus means 1 7, and a horizontal stream supplied by a nozzle 20. The vertical GAN stream prevents air from entering the bottle neck, while the horizontal stream and the vertical stream prevent foam ascending in the headspace of the bottle 1 8 from approaching the focus means and thereby contaminating it The supply means for the GAN streams are described in Fig. 3 which shows a top view of the headspace inertization means according to the invention The arrangement of the foaming means 1 0 with the C0 2 laser 15, the arm 16 of the optical guiding system for the laser beam and the focus means 1 7 in relation to the conveying facilities for the containers 18 is apparent from this view Filled containers 1 8 are delivered by a bottling conveyor 3 1 that rotates clockwise, and is partially shown at the lefthand side, to a transfer conveyor 33 which rotates counterclockwise. Just before the sealing of the bottles 1 8 in the sealing conveyor 32. the laser beam is radiated into a container 1 8 This irradiation takes place just prior to the sealing of the containers 1 8 so that as little ambient air as possible can enter the headspaces of the containers 1 8 before they are sealed. Upon irradiation by the laser beam the beverage liquid contained in the bottles 1 8 foams so that the gas in the headspace is expelled and no ambient air can enter the headspace of the containers 1 8 until they are sealed Supply means 35 and 36 for the GAN hazing streams are also shown in Fig. 3 They may comprise pipes with valves incorporated, leading from a GAN reservoir to the annular nozzle providing GAN stream 21 (Fig. 2) or to the nozzle 20 (Fig. 2) providing the horizontal GAN stream. The supply means 35 comprises a pipe which leads through the arm 16 to the focus means at the radiation point A sensoring means 34 in connection with the triggering control of the laser 1 5 is arranged near the radiation point This sensoring means 34 supplies information about the frequency of the arriving bottles 1 8 so that the laser 1 5 may be triggered exactly in correspondence with said frequency Although the invention has been described by means of an embodiment so far with regard to foaming of beverage in bottles, it is understood that the process and the device according to the invention can also be used for headspace foaming of other containers, e g cans, etc and for the foaming of various beverages, e g beer, soft drinks, etc . in particular carbonated beverases

Claims: Claims A process for the foaming ofthe headspace of containers (18) filled with carbonated beverages, comprising the following steps a) after the filling ofthe beverages into the containers (18) the containers are transferred to a foaming means (10); b) in which an electromagnetic beam is radiated in a controlled fashion into the headspace ofthe container (18) which is not filled with the beverage; c) due to the resultant foaming, the gas volume contained in the headspace is displaced from it; and d) the containers (18) are sealed A process according to claim 1, characterized in that the electromagnetic beam comprises a laser beam. A process according to claim 1 or 2, characterized in that the containers (18) pass through a bottling/filling conveyor (31), a transfer conveyor (33) and a sealing conveyor (32), the point of foaming by means of laser irradiation being located just upstream ofthe point of sealing ofthe containers. A process according to any of the claims 1 to 3 , characterized in that the laser beam is irradiated into the headspace in a pulsed fashion, the laser beam preferably being triggered by an ultrasonic switch or a light barrier A process according to any of the claims 1 to 3 , characterized in that the laser beam is irradiated into the headspace in a continuous fashion A process according to any of the claims 1 to 5. characterized in that the laser beam radiated onto the surface of the beverage is adjusted in its intensity, pulse shape, length and/or frequency A proecess according to claim 6, characterized in a) that the level of foam in the headspace is measured and b) the intensity, pulse shape, length and/or frequency of the laser beam are adjusted dependent on the detected level A process according to claim 6 or 7, characterized in that the average power of the laser beam irradiated onto the surface of the beverage is adjusted in the range of about 10 to about 20000 W, that the frequency of the laser beam is adjusted in the range of about 5 to about 2000 Hz, and that the shutter opening time is in the range of about 5 to about 2000 ms A process according to any of the claims 1 to 8, characterized in that the vicinity of the laser beam irradiation point is surrounded by a haze of an inert gas in order to avoid the entry of ambient air into the headspace and/or contamination ofthe focus means. A device for foaming ofthe headspace of containers (18) filled with carbonated beverages, comprising a) a means (31) for filling the beverage into the containers (18), b) a foaming means (10) to which the containers (18) are transferred after having been filled and by means of which the gas volume previously present in the headspace ofthe containers (18) is displaced from it due to the resultant foaming, and c) a sealing means (32) for the containers (18), characterized in that d) the foaming means (10) comprises electromagnetic beam emitting means (15. 16, 17) for the controlled irradiation of an electromagnetic beam into the headspace ofthe containers (18), not filled with the beverage A device according to claim 10, characterized in that the electromagnetic beam emitting means comprise a laser beam emitter (15, 16. 17) A device according to claim 10 or 11, characterized by a bottling conveyor (31), a transfer conveyor (33) and a sealing conveyor (32), the point of foaming by means ofthe laser beam emitter (15, 16, 17) being located shortly before the point of sealing of the containers (18) A device according to any ofthe claims 10 to 12, characterized by a trigger means, preferably an ultrasonic switch or a light barrier, by means of which the laser beam is irradiated into the headspace in a pulsed fashion. 14. A device according to any ofthe claims 10 to 12, characterized by a laser beam emitter (15, 16, 17) emitting a continuous laser beam. 15. A device according to any ofthe claims 10 to 14, characterized by a controlling means adjusting the laser beam in its intensity, pulse shape, length and/or frequency. 16. A device according to claim 15 characterized by means for measuring or detecting the level of foam in the headspace whereat the intensity, pulse shape, length and/or frequency ofthe laser beam are adjusted dependent on the detected level. 17 A device according to claim 15 or 16, characterized in that the controlling means are adjusting the average power ofthe laser beam irradiated onto the surface ofthe beverage in the range of about 10 to about 20000 W, the frequency ofthe laser beam being in the range of about 5 to about 2000 Hz, and the shutter opening time being in the range of about 5 to about 2000 ms. 18 A device according to any ofthe claims 10 to 17, characterized in that the laser beam emitter comprises a CO 2 laser (15) with an average performance of 10 to 20000 W, a duly cycle of 5 to 100%), an optical guiding system (16) for the laser beam, and a focus means (17) with a lens having a diameter of about 3,81 cm (1,5 in.) and a focal point diameter of 300 to 500 μm. 19. A device according to any of the claims 10 to 18, characterized in that the electromagnetic beam is radiated into the headspace and focused onto the surface of the beverage. 20. A device according to any of claims 10 to 19, characterized by a hazing means surrounding the vicinity of the laser beam radiation point by a haze of an inert gas in order to avoid the entry of ambient air into the headspace and/or contamination of the focus means.

Inventors: BABEL OLAF, BABEL, OLAF
Applicants: BABEL OLAF, BABEL, OLAF
Application year: 1997
Main classification: B67C3
IPC codes: B67C3