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The present invention relates to stoppers, for beverage containers, which are able to be manually removed and reinserted without the help of cork-screw devices and that assure the sealing of the container when inserted for the first time, and the plugging of the container in subsequent insertions.
Cork stoppers are used from the XVIII Century to plug and/or seal wine containers and are spread in the market. Generally, there were no alternatives to cork stoppers until the emergence of sealing stoppers made from plastic material, in the middle of the nineties of the XX Century.
The insertion of a cork stopper into a neck of a wine container is intended to plug the container and at the same time sealing it. On the contrary, the insertion of a stopper into a container with a so-called “spirit” drink is intended to plug the container but not seal it.
The purpose of sealing a container is to avoid that drink leaks through the neck of the container and at the same time to avoid premature changes on the wine quality, which changes are usually imputed to the oxidation.
The purpose of plugging a container is only to avoid that drink leaks through the neck of the container.
When a stopper is used to seal, usually the container is stored in a laid down position, preventing the wine leaks and allowing a slow evolving of the wine only with the amount of oxygen which is given to it by means of the stopper itself. When a stopper is used to plug only, the container is stored upright and the liquid must have enough protection to avoid the oxidation over time or otherwise it is intended that the same become oxidised (for example, Porto Wine and Madeira wine).
For sealing a container, cork stoppers are usually used having lengths of about 38 to 54 mm and a diameter which is usually of 24 mm but which can vary according to the inner diameter of the neck. There must have a difference between the stopper diameter and the neck diameter of about 5.5 to 7.5 mm, in order to assure the sealing. These stoppers are inserted into the neck by compression up to about 15.5 mm and then inserted by a piston device, one of the stopper ends remaining at the same level as the upper end of the neck. These stoppers are never rounded at one end thereof, but they may have a chamfer of about 2 to 4 mm.
The stoppers for sparkling wines are included in this group of stoppers which are used to seal a container. In addition to seal the containers these stoppers may also being manually removed. This manual removal is possible because there is an internal pressure, outwardly exerted by gas released by the liquid, which helps the manual removal action. However, in view of these stopper dimensions it is nearly impossible reusing them manually due to the recovered dimensions that they get after said manual removal action. At the exit of the production line these sparkling wine stoppers have lengths of about 48 mm and diameters of about 30.5 to 31 mm.
To plug a container, stoppers which have lengths of about 27 to 29 mm, rounded at its lower end along about 2 cm of the length thereof, and with a diameter of about 19.5 to 20 mm, but which may vary according to the neck inner diameter, are usually used. The difference between the stopper diameter and the neck inner diameter is never above 2 mm, often being 1.5 mm. The stoppers which are used to plug have crowns from various materials such as plastic, glass, wood and cork. To bottle these stoppers no compression is required, whereby the bottling is achieved by means of a mechanical or manual force in the longitudinal direction, from outside to inside of the container, which force will insert the stopper into the neck of the container up to the crown. The crown rests outside the container in order to provide a later removal easier without the use of any cork screw device.
The sealing stoppers from plastic material have tried to mimic the cork stoppers, either with relation to its general form, namely the dimensions and physical look thereof, or with relation to its sealing efficiency. Like for current cork stoppers, it is necessary a cork screw device to remove these plastic material stoppers from the neck of respective containers. For a very short rest period within the container, a wine is able to deal with the amount of oxygen entering the container due to a poor sealing provided by the plastic material stoppers, however, for longer rest periods of the wine within the container, some signs of premature oxidation arise, which significantly modify the organoleptic characteristics of wine.
Another type of stoppers/sealings to plug and/or sealing containers of wine, and/or similar beverages, are the threaded capsules made from aluminium which are frequently used with other beverage than wine. These stoppers/sealings started to secure the wine market mainly due to a strong commercial attitude coming from Australia and New Zealand, where a significantly amount of bottled wine is sealed with this type of stoppers/sealings. The advantage of the threaded capsules resides in the manner they may be removed, since as a cork screw device is not needed they may be easily removed, which is very convenient especially in the catering sector. However, off-flavour related drawbacks arise due to reduction reactions in the wine by virtue of a complete absence of oxygen admission.
Therefore, a need exists of a competitive price stopper which allows the wine to rest over the time, providing a sealing action and allowing for an easy removal without the use of cork screw devices and being able to be reinserted only by manual pressure and torque.
This stopper, in addition to keep the organoleptic characteristics of wine over the time unchanged must be able to be removed from the neck of the container without require a cork screw device and, additionally, must be able to be reused, allowing to be reinserted in the container neck by means of a manual action only, without the use of any device. Following, these stoppers will be named as “SSR stopper”, that means, stopper which does not need a cork screw device for the removal and reinsertion thereof.
The present invention relates to a cork stopper comprising an upper member or head and a lower member or body, for using with wine and/or beverages containers which comprises the advantages of:
Surprisingly, it has been found that the above advantages, which overcome the drawbacks of the prior art, are achieved with the stopper of the present invention.
Therefore, according to the present invention, the cork stopper, comprising an upper member or head and a lower member or body is characterized by:
Additionally, the cork stopper of the present invention is characterized by said head having a diameter larger than the diameter of the body by at least about 3 mm, and by the shape of said stopper head being cylindrical, cubical, parallelepipedic, conical and the like.
Said cork stopper of the invention can be made from natural cork, clogged natural cork, agglomerated cork and combination thereof, said head and/or said body may comprise at least one disk from natural cork. Said disk is a well known member for the skilled in the art, which disk can be bonded to any of the stopper ends. The cork stopper of the invention may have also, at least in one of its stopper ends, one chamfer of about 2 to 4 mm.
In a preferred embodiment, said cork stopper head of the invention must have a diameter of 30 mm and a height of 20 mm and said body having a diameter of 23 mm and length of 25 mm.
In a further preferred embodiment, said head must have a diameter of 30 mm and height of 20 mm, said body having a diameter of 23 mm and length of 27 mm, the lower end of the body being chamfered with one chamfer of 2 mm.
Still in a further preferred embodiment, said head must have a diameter of 30 mm and a height of 15 mm, said body having a diameter of 24 mm and length of 27 mm, the lower end of the body being chamfered with one chamfer of 4 mm.
In another preferred embodiment, said head must have a diameter of 30 mm and height of 20 mm, the head comprising one natural cork disk of 15 mm height, said body having a diameter of 23 mm and length of 25 mm, the lower end of the body being chamfered with one chamfer of 4 mm.
Still in another preferred embodiment, said head must have a diameter of 30 mm and height of 20 mm, the head comprising one natural cork disk of 15 mm height, said body having a diameter of 21 mm and a length of 25 mm, the lower end of the body being chamfered with one chamfer of 4 mm.
The stopper of the present invention is suitable to plug containers which have beverage selected from the group comprising wine, beer, spirit drinks, water, refrigerants and the like.
A detailed description of the invention is following carried out with reference to preferred embodiments (by way of example) and to the accompanying figures, in which:
FIG. 1 is a schematic side view of a prior art stopper;
FIG. 2A is a schematic side view of a first embodiment of the SSR stopper of the present invention;
FIG. 2B is a schematic side view of second and third embodiments of the SSR stopper of the present invention;
FIG. 3 is a schematic side view of a fourth embodiment of the SSR stopper of the present invention;
FIG. 4 is a graphic which shows the absorption in bottle as a function of time from a sealing ability test;
FIG. 5 is a graphic which shows the free SO2 content as a function of time from a sealing ability test;
FIG. 6 is a graphic which shows the total SO2 content as a function of time for different stoppers used in a sealing ability test.
The present invention relates to a novel cork stopper comprising an upper member (1) or head and a lower member (2) or body, for use with wine and/or beverage containers.
This Novel Stopper Fully Overcomes the Drawbacks of the Prior Art Stoppers.
In this description, the term “cork stopper” relates to stoppers made from natural cork, clogged natural cork, agglomerated cork and combination thereof. According to ISO 2190, the term “agglomerated cork stopper” relates to an agglomerated cork stopper comprising at least 51% (by weight) of granulated cork having a minimum grain size of 0.5 mm, a maximum specific weight of 60 Kg/m3 and a water content equal or less than 8%. The term “manual” relates to any action performed by a user without using any automated, mechanical, electrical, electronic devices or the like. The term “rounded stopper” relates to a stopper which edge, of any of its ends, is rounded by friction. Additionally, the term “chamfered stopper” relates to a stopper which edge, of any of its ends, is angularly cut, in order to decrease the face diameter of any of said ends, for example, to make easy to insert the stopper into the neck. The term “reuse” relates to a stopper which may be used for multiple insertions and/or removal from the neck of the container. The terms “first bottling” or “first bottling action” relates to the first time, after its production, a stopper is inserted into the container neck. Usually this first action is performed in the factory and is usually done in an automated manner. The term “disk” relates to a cork member which can be bonded to any of the stopper ends. Usually this member adheres to stopper end(s) by means of gluing and has exactly the same profile with respect to the end(s) where it is adhered. Usually its height is higher than at least about 1 mm, but may vary significantly. Usually this member is made from natural cork which has better quality than the respective cork where it is adhered.
Generally the stoppers of the prior art are divided into three categories.
The first category includes stoppers which seal a beverage container. This type of stoppers does not allow for its manual removal due the stopper is fully inserted within the neck of the container, and so require a cork screw device for the removal. These stoppers can not be used to plug again (i.e., being reinserted in the same container) by means of a manual action only, or otherwise it is necessary to apply an high manual force after a rotation of 180° of the stopper ends to achieve such task, thus inserting the starting upper end of the stopper in the edge of the neck in order to subsequently push the stopper into the container neck. This manual reuse action is achievable because the fit end of the stopper which was not in contact with the liquid in the container during the starting bottling is used, since it does not have a starting shape recovery with the same magnitude as the initial bottling lower end which have contacted the beverage, thus being possible to reinsert it into the neck of the container in a reusing situation. However this process is not advisable nor desirable as the current fit end of the stopper would have been subjected to a mechanical action of drilling by a cork screw device by the time of removal, whereby it has its integrity damaged by said drilling action and additionally the required manual force to insert it into the neck is so high that often damages the current fit end. Note that this latter end was exposed to environment and to the user handling, whereby, in the sake of healthfulness, it is not advisable to be brought in contact with the beverage. Accordingly, when the stopper is reused, the hole drilled on its end will face the beverage inside the container, thus releasing stopper material debris to said beverage. This event is not desirable. Another drawback resides in the mechanical process to remove the stopper from the container neck that includes the use of a cork screw device, which device often does a through hole, end to end, in the stopper and therefore the resulting stopper debris falls into the beverage, which is not desirable either. Additionally, this fully drilled stopper loses its ability to plug the container.
The second category includes stoppers usually used in sparkling wine containers, for example. These stoppers also seal the containers but they differ from the preceding category because they allow for manual removal. These stoppers have about 30.5 to 31 mm diameter (d) and about 48 mm length (c), FIG. 1, whereby the manual removal is achievable only due to the internal pressure outwardly exerted by gas released by the beverage itself, which pressure helps the manual removal action. Additionally, it becomes nearly impossible to reuse these stoppers manually due to its recovered external diameter (d) after the removal action.
Lastly, the third category comprises stoppers which are designed to plug (but not sealing) the containers, so as to prevent only beverage leaks through the neck of the container. These stoppers, used with containers having the so-called “spirit” beverages, are usually able to be used manually only but they do not seal the container. These stoppers, as above mentioned, are formed by a cylindrical body with a small length and by a removal crown.
In the first and second categories, said sealing stoppers have lengths (c) which may vary from about 38 to 54 cm and diameters (d) which must have a difference between the stopper diameter (d) and the neck diameter of about 5.5 to 7.5 mm, in order to assure the sealing effect. These stoppers are formed as single pieces by boring of natural cork or by extrusion or moulding of granulated cork, having a cylindrical shape, and the bottling process being usually mechanical and including, in both cases, a starting insertion into the neck of the container with a previous compression and a subsequent use of a piston so as to insert the remaining of the stopper into the container.
In the third category, the beverage container plug only stoppers have lengths which vary from about 27 to 29 mm and diameters which must have a difference between the stopper diameter and the neck diameter not higher than 2 mm. These stoppers comprise a head/crown and a body which are usually formed from different materials. The bottling process is performed by a mechanical or manual force, which is longitudinally exerted from outwards to inwards with respect to the container, to insert the stopper into the neck of the container up to the crown.
The novel stopper of the present invention will form a fourth stopper category because it is able to seal and at the same time is manually removable, it is able to be reused/reinserted into the same container without the risk of become damaged or deteriorate the container content, and high forces or the use of mechanical devices are not required to the removal/reinsertion.
Therefore, the novel stopper of the present invention overcomes the drawbacks from the stoppers of the prior art, and gathers the main advantages of the latter.
With reference to FIG. 2A-3, the SSR stopper herein disclosed comprises two members (1, 2). The existence of two members (1, 2), upper and lower, respectively, having different well defined sizes imparts the manual reuse ability to the SSR stopper, while keeping the sealing ability of the prior art sealing stoppers by the time of the first bottling. This association of features were not possible with stoppers of prior art.
In order to assure such a manual only reuse, the upper member (1) or head of the SSR stopper is the part of the SSR stopper which remains outside the container neck after bottling, and must have an height (a′, a″) of at least about 8 mm, and if it has a circular profile, must have a diameter (da′, da″) which must be larger than the diameter (d′, d″) of the body (2) by at least about 3 mm. It should be pointed out that the profile of the SSR stopper head (1) may be not circular only, being allowed to assume any profile obtainable by the SSR stopper production processes. It is also contemplated that the head (2) may comprise at least one cork disk (4) with the same profile in its upper end, if desired.
The lower member (2) or body of the SSR stopper must be cylindrical and may comprise at least one cork disk (4) with the same profile and/or a chamfer (3) on its lower end. This lower member (2) or body is the part of the SSR stopper which remains fully within the container neck after bottling. Surprisingly, it was found that in order to achieve a combined ability of manual only reuse and sealing features, the SSR stopper body (2) must have a length (c′, c″) of about 10 to 30 mm and, for the case of standard necks having diameters from 16.5 to 18 mm, must have a diameter (d′, d″) of about 21 to 26 mm. As can be confirmed, the dimensions (c′, c″; d′, d″) of the SSR stopper body (2) of the present invention, particularly the length (c′, c″) of the SSR stopper body (2), reside between the production values for sealing stoppers and the production values for plugging but not sealing stoppers, both from prior art.
In the bottling process, the SSR stopper head (1) must be abutted to the edge of the container neck, the SSR stopper body (2) being fully inserted into the neck.
The reinsertion process of a SSR stopper into a container neck is similar to that used for the plugging but not sealing stoppers of prior art, being able to be performed in a manual only manner, which overcomes in this case the lack of starting sealing action (after the first bottling action) evidenced by stoppers of prior art, since the SSR stopper of the invention assures the container sealing in the starting bottling.
With respect to sealing stoppers of prior art, the SSR stopper of the present invention is clearly advantageous because it keeps the advantages of the sealing action but overcomes the problems related with the manual removal and reuse evidenced by said sealing stoppers of prior art.
With reference to FIG. 2A, in a preferred embodiment according to the invention, an SSR stopper comprises an upper member (1) or head, having a circular cross-section, and a cylindrical lower member (2) or body. The head (1) and the body (2) are formed into a single cork piece. The head (1) has a diameter (da′) of 30 mm and an height (a′) of 20 mm, the body (2) having a diameter (d′) of 23 mm and a length (c′) of 25 mm
With reference now to FIG. 2B, in another preferred embodiment according to the invention, an SSR stopper comprises a head (1), having a circular cross-section, and a cylindrical body (2). The head (1) and the body (2) are formed into a single cork piece. The head (1) has a diameter (da′) of 30 mm and a height (a′) of 20 mm, the body (2) having a diameter (d′) of 23 mm and a length (c′) of 27 mm. This SSR stopper is further chamfered with a chamfer (3) of 2 mm, on the lower end of the stopper body (2).
Still with respect to FIG. 2B, in another preferred embodiment according to the invention, an SSR stopper comprises a head (1), having a circular cross-section, and a cylindrical body (2). The head (1) and the body (2) are formed into a single cork piece. The head (1) has a diameter (da′) of 30 mm and an height (a′) de 15 mm, the body (2) having a diameter (d′) of 24 mm and a length (c′) of 27 mm and the lower end of the body (2) being chamfered with a chamfer (3) of 4 mm.
In relation to FIG. 3, in another preferred embodiment according to the invention, an SSR stopper comprises a head (1) having a circular cross-section and a cylindrical body (2). The head (1) and the body (2) are formed into a single cork piece. The head has a diameter (da″) of 30 mm and a height (a″) of 20 mm, comprising one disk (4) having an height (ad″) of 15 mm. The body (2) has a diameter (d″) of 23 mm, length (c″) of 25 mm and a chamfer (3) of 4 mm on the lower end thereof.
Still with reference to FIG. 3, still in another preferred embodiment, said head (1) has a diameter (da″) of 30 mm and an height (a″) of 20 mm, the head (1) comprising one disk (4), from natural cork, of 15 mm height, said body (2) having a diameter (d″) of 21 mm and a length (c″) of 25 mm, the lower end of the body being chamfered with a chamfer (3) of 4 mm.
A number of agglomerated cork stoppers with the dimensions shown in table 1 were produced by extrusion followed of grinding to desired size in order to test it with bottles having standard neck (CETIE).
All the produced stoppers, shown in table 1, were subjected to a standard surface treatment with Bopsil in an amount of 15 mg/stopper. The stoppers were further subjected to a white washing process.
|SSR stoppers and respective dimensions|
Bottling tests with bottles having standard neck (CETIE) were made using the above stoppers (Table 1). It was intended to assess how easily persons with different muscular strength were able to remove the stoppers from the bottlenecks. The results are shown in Table 2.
|Qualitative assessment of SSR stopper removal|
|SSR||Woman 1||Woman 2||Man 1||Man 2|
The above Table 2 shows a relation between the stoppers of Table 1 and the ease of removal of the same from standard neck containers. The assessment of such ease of stopper removal was made in a qualitative manner by groups of persons with different muscular strengths. Therefore, the A letter means an easy removal, the B letter means a difficult removal and the C letter means impossible to remove.
Based on said assessment it was possible to select ideal dimensions for SSR stoppers of the present invention so as to be possible to remove them manually from standard bottlenecks. As can be seen from Table 2, said ideal stoppers are that numbered with 1, 2, 9, 15, 16, 17 and 18.
Bottling tests were made to check the sealing ability of SSR stoppers of the present invention by comparison with the sealing ability of agglomerated stoppers of prior art.
The stoppers selected for comparison were:
All the agglomerated stoppers of prior art were made in a conventional manner, by extrusion of rods having 25 mm, and subjected to a standard surface treatment using Bopsil, 15 mg/stopper, and a white washing.
All the SSR stoppers 15 were made by extrusion of 32 mm rods, followed of grinding and subjected to a standard surface treatment using Bopsil, 15 mg/stopper. These stoppers were split into two groups, one of the groups was subjected to a white washing process (SSR stoppers 15b) and the other group was subjected to a cork like colour washing process (SSR stoppers 15c).
With respect to the production process, although an extrusion is used for both types stoppers, the feed rate and temperature of the extrusion device are different in relation to the SSR stoppers of the invention and the agglomerated stoppers of prior art, due to different dimensions (above-mentioned) of respective rods.
Greenish-white wine from “Sociedade Vinhos Borges” was used in the bottling test as well as “Bordalesas” bottles having a 750 mL capacity and a greenish colour.
The stoppers were delivered as follows:
35 bottles with agglomerated stoppers;
20 bottles with SSR stoppers 15b;
20 bottles with SSR stoppers 15c.
Due to different shape of stoppers, a wine bottling line was used to bottle the agglomerated stoppers and a champagne bottling line was used to bottle the SSR stoppers.
All of the bottles were stored in a laid down position at the room temperature.
The bottles were analyzed and grouped as shown in the following Table:
|No of Bottles per Stoppers|
|Time||Agglomerate||SSR 15b||SSR 15c|
During the test all the SSR stoppers 15 were removed and reinserted from/into the bottles quite easily after 3, 6 and 12 months.
With respect to FIG. 4, in relation to the absorption in bottle, the shown results were achieved by variation of stopper weights measured before the starting bottling and after its removal in the end of each time period shown in the figure.
It was found that the absorption in the SSR stoppers is low and substantially lower than that of the agglomerated stoppers of the prior art. This occur since, due to the differences in the production process (described above), the SSR stoppers (formed herein from 32 mm rods) are more compressed than the agglomerated stoppers of the prior art (formed from 25 mm rods) and therefore the absorption of the former is lower than that of the latter. Additionally to the production process, the formulation used in the SSR stoppers has an amount of paraffin which is slightly higher than that used in the agglomerated stoppers of prior art. This may explain the different absorption, which means the absorption differences found in both types of stoppers do not have any relation with the shape thereof.
With reference to FIGS. 5 and 6, the shown results relative to the plotted lines related with the amount of the free SO2 (FIG. 5) and total SO2 (FIG. 6), were achieved by potentiometric titration.
The progress of free and total SO2 amounts is the same for both SSR stoppers 15b and SSR stoppers 15c. On the contrary, the losses of free and total SO2 in sealed wines having agglomerated stoppers of the prior art are lower, because, due to its higher absorption, these stoppers get expanded and therefore achieve a tightly adjustment to the neck.
Also, the total SO2 amounts are higher after 12 months, because the company that carried out the measurements have changed the method used in the preceding measurements. However, this fact does not interfere with the results, since the relative value between sealings is the same.
Along 3 test periods a profile tasting test was carried out by comparison between wines sealed with SSR stoppers of the invention and agglomerated stoppers of the prior art. The purpose of this test was to check either the wine quality change according to the sealing or not. This test was carried out with the help of a triangular test according to the rule NF ISO V09-013.
The stoppers used in this test were the same as in the preceding example, comprising agglomerated stoppers of prior art and SSRb and SSRc stoppers of the present invention. Arrangements of three samples of wine were made. Each wine taster had necessarily to report one of said three samples as being different from the others (even if he/she did not find any in such condition). Following, the correct answers were established and compared with a so-called critical number which matched with the minimum number of correct answers in order to assume the samples as statistically different. This critical number is established in a table of the ISO rule and varies with the number of the tasters.
In order to clarify the above-mentioned, there is shown below the Table 3 including the test data.
|Profile tasting tests|
|A, SSRb, SSRb||9||2||6||ns|
|A, A, SSRb||9||3||6||ns|
|SSRb, SSRb, A||9||3||6||ns|
|SSRb, A, SSRb||9||3||6||ns|
|A, A, SSRb||9||2||6||ns|
|Total of answers||45||13||21||ns|
|A, A, SSRc||9||3||6||ns|
|SSRc, SSRc, A||9||3||6||ns|
|SSRc, A, SSRc||9||2||6||ns|
|A, SSRc, A||9||3||6||ns|
|F5, SSRc, A||9||4||6||ns|
|Total of answers||45||15||21||ns|
The meaning of items shown in the above table is as it follows:
“NP”—Number of tasters,
“NRC”—Number of correct answers,
“ns”—wine which did not change,
“A”, “F5”—stoppers of the prior art.
With respect to the oxidation after 3 and 6 months, tasters did not notice any significant statistical difference between wines. After 12 months, three of the tasters considered that 3 bottles having agglomerated stoppers of the prior art have oxidized, although statistically such difference was not significant.
In relation to the sealing ability, the bottling test along one year have proved that the SSR stoppers according to the present invention, have a behaviour similar to that of agglomerated stoppers of prior art used as the reference stoppers. The differences found with respect to absorption are due to the different production process used (as above-mentioned) and not to the dimensions and shape of stoppers.
In relation to the SSR stoppers of the present invention, these have proved its ability to a manual only reuse, since they were easily removed and reinserted from/into the bottles.
The results show clearly that after 12 months the SSR stoppers of the present invention have a sealing ability similar to the agglomerated stoppers of the prior art used as reference stoppers in the bottling test.