SPARKLING BEVERAGE CONTAINER WITH IMPROVED BUBBLING BEHAVIOR

Abstract

Carbonated beverage container 1, in particular a glass, comprising a sealed wall made of at least one structural material, the sealed wall defining an internal surface having a bottom portion between a bottom 4 of the sealed wall and a region of maximum diameter and an edge portion located above the bottom portion, the sealed wall comprising, in the bottom portion, a plurality of open pores 6 forming a pattern occupying an area of between 0.01 and 5%, preferably between 0.10 and 1%, of the area of the bottom portion and having an open cross shape.

Claims

1. A sparkling beverage container (1), in particular a glass, comprising a barrier wall made of at least one structural material, the barrier wall defining an internal surface having a bottom portion between a bottom (4) of the barrier wall and a region of maximum diameter and an edge portion located above the bottom portion, the barrier wall comprising, in the bottom portion, a plurality of open pores (6) forming a pattern occupying an area of between 0.01 and 5% of the area of the bottom portion and having an open cross shape.

2. The sparkling beverage container according to claim 1, wherein the cross has straight-line segment branches.

3. The sparkling beverage container according to claim 1, wherein the cross has a number of branches comprised between 3 and 10, said branches are contiguous or not contiguous.

4. The sparkling beverage container according to claim 1, wherein the cross has at least one discontinuity.

5. The sparkling beverage container according to claim 1, wherein the pattern has a plurality of point areas having said pores.

6. The sparkling beverage container according to claim 1, wherein the barrier wall forms a gob (3) having a diameter at the mouth smaller than a diameter at mid-height and a height greater than a diameter at mid-height.

7. The sparkling beverage container according to claim 1, wherein said cross has at least two branches extending, in developed length, over more than 90% of the maximum radius of the bottom portion, said two branches being opposite if the number of branches is even and disposed at least 120° from each other if the number of branches is odd.

8. The sparkling beverage container according to claim 1, wherein the cross is centered on an axis of symmetry of the container.

9. The sparkling beverage container according to claim 1, wherein the cross has branches with a width comprised between 0.1 and 5 mm.

10. The sparkling beverage container according to claim 1, wherein the cross has branches of equal lengths, equal widths, and a discontinuity in the center.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Other features, details and advantages of the invention will appear upon reading the detailed description below, and the appended drawings, wherein:

[0047] FIG. 1 is a sectional view of a container according to one aspect of the invention,

[0048] FIG. 2 is a sectional view of a container according to one aspect of the invention,

[0049] FIG. 3 is a sectional view of a container according to one aspect of the invention,

[0050] FIG. 4 is a cross-sectional photo of a container according to one aspect of the invention,

[0051] FIG. 5 is a cross-sectional photo of a container according to one aspect of the invention,

[0052] FIG. 6 is a cross-sectional photo of a container according to one aspect of the invention,

[0053] The drawings and the description below contain, for the most portion, certain elements. They may therefore not only be used to better understand the present invention, but also contribute to its definition, if necessary.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0054] In a food liquid, the carbon dioxide (CO.sub.2) dissolved in the liquid phase is the carrier gas of the effervescence phenomenon. The frequency of emission of bubbles during a tasting, the magnification of the bubbles in the container and the number of bubbles liable to be formed are related to a certain number of physico-chemical parameters of the liquid phase and of the container in which tasting is performed.

[0055] When a gas is contacted with a liquid, a portion of this gas dissolves in the liquid. Various factors influence the solubility of gas in liquid, in particular temperature and pressure. At equilibrium, there is a proportionality between the concentration in the liquid phase of a chemical species i, denoted Ci, and its partial pressure in the gas phase Pi. Henry's law is written:

C.sub.i=kH P.sub.i  [Math 1]

[0056] The proportionality constant kH is called Henry's constant. It strongly depends on the gas and the liquid considered, as well as on the temperature.

[0057] Under normal atmospheric pressure P.sub.o≈1 bar, taking into account the solubility of CO.sub.2 in a beer at 4° C. which is worth kH≈2.6 g/L/bar, said beer is capable of dissolving approximately 2.6 g/L of CO.sub.2.

[0058] When a chemical substance i is in equilibrium on either side of a gas/liquid interface, its concentration in the liquid meets Henry's law. The liquid is then said to be saturated with respect to this substance. In this case, saturation means balance.

[0059] When the concentration CL of a chemical substance i in a liquid is greater than predicted by Henry's law, the liquid is supersaturated with respect to that substance. To quantify this non-equilibrium situation, the supersaturation coefficient Si is defined as the relative excess of concentration in a liquid of a substance i with respect to the reference concentration, denoted CO (chosen as the equilibrium concentration of this substance under a partial pressure equal to the pressure in the liquid PL). The supersaturation coefficient Si is therefore defined in the following form:

S.sub.i=(C.sub.i−C.sub.0)/C.sub.0  [Math 2]

[0060] When a liquid is supersaturated with respect to a chemical substance, we have Si>0. The liquid evacuates a portion of its content in this chemical substance to return to a new state of equilibrium which meets Henry's law.

[0061] In tasting conditions, in a container, the pressure in the liquid is almost identical to the ambient pressure. Given the low height of the liquid, which does not exceed 10 to 12 cm, the effect of the hydrostatic overpressure which reigns at the bottom of the container is negligible compared to atmospheric pressure. At a temperature of 4° C., it is then possible to deduce the equilibrium concentration as being equal to:

C.sub.0=K.sub.HP.sub.L≈K.sub.HP.sub.0≈2.6 g/L  [Math 3]

[0062] Beers do not all have the same dissolved CO.sub.2 concentration. Some are lightly loaded at 3-4 g/L, while others are heavily loaded, up to 7-8 g/L. Their respective supersaturation coefficients with respect to dissolved CO2 will therefore not be the same. In the case of an average beer, loaded at about 5 g/L. Its supersaturation coefficient (at 4° C.) by applying the equation [Math 2]:

S.sub.CO2=(C.sub.i−C.sub.0)/C.sub.0≈(5−2.6)/2.6≈0.9  [Math 4]

[0063] For comparison (still at 4° C.), strongly sparkling waters (of the Badoit Rouge type) have supersaturation coefficients of around 1.3, while Champagne wines (still young) have much higher coefficients, of the order of 3.4. In general, the higher the supersaturation coefficient of a liquid loaded with dissolved CO.sub.2, the more intense the resulting dissolved carbon dioxide escape kinetics will be in order to return to Henry's equilibrium. However, it has been observed that the supersaturation of a liquid in dissolved gas is not necessarily synonymous with the formation of bubbles and therefore effervescence.

[0064] Indeed, at beer supersaturation values, the formation of bubbles requires the presence of gas pockets in the medium, whose radius of curvature rc exceeds a value called critical value defined as follows:

rc=2γ/P.sub.oS  [Math 5]

[0065] where γ is the surface tension of the liquid, Po is the ambient pressure and S is the supersaturation coefficient of the liquid phase in CO.sub.2.

[0066] At normal atmospheric pressure of 1 bar and at 4° C., in the case of a beer whose surface tension is typically 45 mN/m and the supersaturation coefficient is around 0.9, the previous equation shows a critical radius of the order of 1 μm below which the formation of bubbles does not take place.

[0067] To cause CO.sub.2 bubbles to appear and grow in an effervescent wine, the medium contains therein gas microbubbles whose radii are greater than a critical radius. This is referred to as non-classical heterogeneous nucleation (as opposed to the nucleations called classical nucleations which concern the spontaneous formation, ex nihilo, of bubbles in a highly supersaturated liquid). Classic nucleations require very high dissolved gas supersaturation coefficients (>100), which are incompatible with sparkling beverages.

[0068] The question then arises of the origin of the gas germs which are the catalysts of the effervescence in a container.

[0069] The critical nucleation radius takes into account the concentration of dissolved CO.sub.2 in the beverage, cf. equations [Math 4] and [Math 5]. However, after serving, said concentration is no longer the same as the initial concentration. Serving is a critical step. Indeed, the pouring into the container generates significant turbulence which accelerates the escape of the dissolved carbon dioxide. The colder the beverage, the more dissolved carbon dioxide is kept dissolved at the time of serving. Indeed, the beverage is particularly viscous as it is cold. However, the diffusion rate of dissolved CO.sub.2 out of the beverage is all the more rapid as the viscosity is low. In addition, the turbulence of pouring is particularly effectively reduced when the beverage is viscous. Consequently, the colder the beverage is served, the better the conservation of dissolved carbon dioxide during service.

[0070] For effervescent wine, the critical radius is influenced by several factors: type of wine, sugar level, composition, etc.

[0071] Moreover, it has been established that the flow of bubbles, that is to say the number of bubbles per second, is proportional to the square of the temperature, to the concentration of CO.sub.2 dissolved in the liquid, and inversely proportional to the dynamic viscosity (in kg/m/s).

[0072] By looking more closely at the bubbling phenomenon of effervescent wines, the Applicant has carried out tests by implementing effervescent wine glasses whose bottom is made rough by laser shots on the uncoated glass wall. The glass after a normal finish giving it a smooth surface is treated with a laser beam generating controlled impacts in the bottom wall from the internal surface.

[0073] Unlike beer glasses whose bottom is generally flat, effervescent wine glasses, of the flute or goblet type, have bottoms of variable height, in particular inverted ogive, parabolic, brace, etc. of various curvatures.

[0074] These tests have shown the interest of a radially distributed bubbling, in particular by the mixing caused by the distributed bubbling by mass convection.

[0075] A container 1 is shown in the figures. The container 1 here is in the shape of a stemmed glass. The method described below applies to most containers for sparkling beverages for which the control of effervescence is of interest.

[0076] The container 1 comprises, here, a foot 2 and a gob 3. The gob 3 comprises a bottom 4 and an upper wall 5 of substantially cylindrical or frustoconical shape. The container 1 is, here, axisymmetric. In the example described here, the bottom 4 and the gob 3 form a one-piece body. The gob 3 has an inner bottom surface and an inner edge surface. The gob 3 is watertight. The internal surfaces are intended to be in contact with the beverage when using the container 1.

[0077] The container 1 can be obtained by manufacturing techniques known as such, for example by pressing, blowing and/or by centrifugation. At the output of such manufacturing techniques, the interior of the container 1 is substantially smooth and uniform. The container 1 is marketable as is.

[0078] The smooth container 1 is treated to form blind perforations 6 on the upper surface of the bottom 4 located on the side of the upper wall 5, that is to say the internal bottom surface.

[0079] The perforations 6 are applied to the bottom of the gob 3 in a cruciform pattern. The pattern here is a cross with 4 branches of equal length, equal width and circumferentially regularly distributed. The material of the container 1, here a glass, is the object of laser shots forming the perforations 6 and thus determining the pattern.

[0080] The pattern has a length slightly less than the maximum inner diameter of the gob 3, for example greater than 90% of the maximum inner diameter of the gob 3.

[0081] The cross can have diametrical branches of length comprised between 4 and 6 cm. The cross here has an open shape. The crosses comprising closed shapes, lobed crosses, Celtic crosses, are less interesting. Indeed, a circular pattern would have a length of PI times the diameter while the square cross has a length of 2 times the diameter, hence faster manufacturing and slow and persistent bubbling while offering a satisfactory appearance and efficient mixing.

[0082] The branches of the cross can have a width of a few tenths of a millimeter to a few millimeters, for example between 0.025 and 0.080 mm, more generally comprised between 0.1 and 5 mm. A branch of the cross can be formed of perforations 6 disposed randomly within the pattern or disposed in an ordered manner, for example in one or more rows.

[0083] In relation to the area of the bottom portion, the pattern occupies an area comprised between 0.01 and 5%, preferably between 0.10 and 1%. Such a surface allows prolonged bubbling of at least 10 minutes.

[0084] The cross can have branches of constant or variable width.

[0085] The cross can have branches in an even number, 4, 6, 8 or 10, passing through the center or interrupted near the center.

[0086] The cross can have branches in an odd number, 3, 5, 7 or 9, passing through the center or interrupted near the center.

[0087] The interruption in the center allows a more homogeneous distribution of the perforations 6 on the surface of the bottom portion.

[0088] In FIG. 1, a stemmed glass has a cruciform design. The gob 3 has a maximum diameter comprised between 40 and 45% of its internal height. The gob 3 has an internal height comprised between 180 and 200% of the maximum diameter.

[0089] In FIG. 2, a stemmed glass has a cruciform design. The gob 3 has a maximum diameter comprised between 45 and 50% of its internal height. The gob 3 has an internal height comprised between 170 and 180% of the maximum diameter.

[0090] In FIG. 3, a stemmed glass has a cruciform design. The gob 3 has a maximum diameter comprised between 70 and 80% of its internal height. The gob 3 has an internal height comprised between 110 and 130% of the maximum diameter.

[0091] FIG. 4 shows the comparison between two flute-shaped champagne glasses, one known in smooth glass on the left and the other, according to the invention, filled with the same champagne under the same operating conditions of pressure, temperature, luminosity, etc. Said other glass is provided with perforations 6 close to the center and therefore to the bottom of the glass. The movement of the wine generated by the bubbling is visible and the rotary stirring movement is significant.

[0092] FIG. 5 shows a glass filled with champagne, according to the invention, with a cruciform pattern as in FIGS. 1 to 3. A curtain of bubbles is visible and causes significant mixing with slow and stable degassing.

[0093] FIG. 6 shows a glass filled with champagne, according to the invention, with a cruciform pattern as in FIGS. 1 to 3. After 10 minutes of bubbling the glass held still, a curtain of bubbles remains visible and maintains stirring.