DK147273B - CARBON ACID ADDITION FOR BEVERAGES - Google Patents

Description

147273

The present invention relates to an apparatus for carbonated beverage additives, in particular carbonated additives at the time of use.

Commercial carbonated beverage additives are usually made by contacting the beverages with carbon dioxide under pressure and intensive mixing in a cooled container. These commercial addition methods require a complicated and refined equipment that is not present in the home or at the time when the beverages are to be enjoyed.

Simple carbon dioxide addition systems known for use in the home are known. Generally, with these known carbon dioxide addition systems, a chemical "reaction pair" is used to produce carbon dioxide in situ in the beverage to be added to carbonic acid. Such a reaction pair usually consists of a combination of an inorganic carbonate such as sodium bicarbonate and an edible acid such as citric acid or an ion exchange resin which acts as an acid. Contact between compounds of this type in aqueous solution results in the formation of gaseous carbon dioxide and a salt of the edible acid. In the descriptions of several patents (U.S. Patent No. 3,241,977, U.S. Patent No. 3,467,526, U.S. Patent No. 3,492,671, and U.S. Patent No. 2,742,363), preferred embodiments of such acid hydrogen carbonate are described in detail. or acid resin hydrogen carbonate systems. However, all of these methods result in the formation of undesirable flavoring organic salts in solution or require the use of a complex ion exchange material to prevent these salts from being dissolved in the beverage.

Such salts are particularly noticeable to the consumer and therefore particularly unfortunate when formed in substantial quantities to obtain relatively large carbonic acid additives.

Another method of carbonic acid addition in the home is based on the use of dry beverage compositions containing water-reactive carbonic anhydrides which release COg or HgCOg in aqueous solution (cf. U.S. Patent No. 3,441,417).

However, these agents have a rather complex composition and in many cases necessitate the addition of a buffer system to the beverage solution.

Specifically, from United States Patent Specification No. 2,742,363, an apparatus for carbonating beverage additives comprising a water-impermeable container is known to the inside of which is attached a carbon dioxide-releasing material. However, this carbon dioxide-releasing material is precisely of the above-mentioned type, where carbon dioxide is produced on the basis of an alkali metal hydrogen carbonate and an acid ion exchange resin, and the apparatus of this United States patent is therefore also precisely associated with the above-mentioned drawback.

The object of the present invention is to provide a simple but effective apparatus for adding carbonated beverages to beverages at the time of ingestion of the beverage, which is not subject to the disadvantages of the present invention and does not give rise to the build-up of flavoring salts of various kinds.

This object is achieved with apparatus according to the invention, characterized in that the carbon dioxide-releasing material is a porous crystalline aluminum silicate material selected from a group consisting of Zeolite X, Zeolite Y, Zeolite A and Faujasite, having a pore size of from 3 to 10 Å. wherein at least 5% by weight of carbon dioxide is absorbed in the aluminum silicate material and a sufficient amount of aluminum silicate material is attached to the container to obtain from 17 to 135 g of crystalline material per minute. liter capacity of the container.

Using the apparatus of the invention, a liquid beverage is contacted with the porous crystalline aluminum silicate material in the interior of the container.

The carbonic acid addition with the apparatus of the invention is preferably carried out at a temperature below about 43 ° C and atmospheric pressure.

Zeolite X has the general formula: (0.9 ± 0.2) M 2 O: Al 2 O 3: (2.5 + 0.5) SiO 2: (0-8) HgO, n

Zeolite Y has the general formula: (0.9 ± 0.2) M 2 O: Al 2 O 3: (3-6) SiO 2: (0-9) H 2 O, n

Zeolite A has the general formula: (1.0 ± 0.2) M 2 O: Al 2 O 3: (1.85 ± 0.5) SiO 2: (0-6) H 2 O n and Faujasite have the formula: (Na, Ca) 3 AI, Si. | 92 ^ 384 ^ H2 O where M represents a metal and n the valence of the metal.

147273 3

An embodiment of the apparatus according to the invention is characterized in that the crystalline aluminum silicate material comprises granules which form a liner which adheres to or is bonded to the inner surfaces of the container.

Another embodiment of the apparatus according to the invention is characterized in that the crystalline aluminum silicate material comprises a single molded block having a thickness of from 0.025 mm to 7.5 cm fixed within the container.

A third embodiment of apparatus according to the invention is characterized in that the block is attached to the bottom of the container.

In the following, the invention will be described in more detail with reference to the drawing, in which: 1 is a graph showing the effect of molecular sieve pore size on carbonic acid addition to water. The horizontal axis represents the carbon addition time in minutes. The vertical axis represents a dimensionless indication of dissolved carbon dioxide expressed as the volume of gaseous carbon dioxide (at 0 ° C and 1 atmosphere) dissolved per volume of liquid added to carbon dioxide (at 1.7 ° C and 1 atmosphere). The five curves are carbon dioxide addition profiles at 1.7 ° C and 1 atmosphere obtained for five different types of molecular sieves currently commercially available from the Molecular Sieve Department of the Material Sciences Division (formerly Linde Division) of the Union Carbide Corporation, FIG. 2 is a graph showing the "4 minute carbonic acid addition factor" as a function of the molecular sieve pore size. The horizontal axis represents the molecular sieve pore size in Angstrom.

The vertical axis represents the "4-minute carbon dioxide addition factor", a dimensionless number defined as:

Volume COg dissolved Volume COg dissolved after four minutes after four minutes_x progress_

Volume COg dissolved Volume COg available by saturation in the use they aim 4 147273

The two curves represent 12 g and 24 g portions of molecular sieves used to add carbonic acid to 237 cm 3 of water at 1.7 ° C and 1 atmosphere. Fig. 3 is a perspective view of an embodiment of an apparatus according to the invention in which a section is removed; 4 is a perspective view of another embodiment of the apparatus of the invention, from which apparatus a section has also been removed.

Molecular sieves of the type used in connection with the apparatus of the present invention are, as mentioned, crystalline aluminum silicate materials of the following general formula: M 2 O * SiO 2 -AAl 2 O 3 -bH 2 O n in the salt form, where n is the valence of a metal cation M, with M usually being Na or K, but may be other cations introduced by exchange, a is the number of moles of alumina, and b is the number of moles of hydrate water.

Upon removal of at least some of the hydrate water upon heating, the crystalline aluminum silicates become highly porous and are characterized by a series of surface cavities and internal pores forming a continuous network of passages in the crystal.

Such dehydrated molecular sieves are often referred to as "activated" with the meaning that they are ready to adsorb carbon dioxide. Due to the crystalline nature of these materials, the diameters of the surface cavities and of the inner pores are substantially constant and of molecular size. For this reason, the crystalline aluminum silicates have found widespread use in separating materials by molecular size or shape, and as a result have been named molecular sieves.

Molecular sieves or crystalline aluminum silicates are also sometimes referred to as crystalline zeolites and are of both natural and synthetic origin. Naturally occurring crystalline aluminum silicates exhibiting molecular sieve activity include, e.g. analite, paulingite, ptilolite, clinoptilolite, ferrierite, chabazite, gmelinite, levynite, erionite and mordenite.

Since not all the naturally occurring crystalline aluminum silicates are sufficiently available, considerable attention has been paid to the production of synthetic equivalents.

Two basic types of crystalline aluminum silicate molecular sieves, which are most readily available on a commercial scale, have been known in the art as "Zeolit X" and "Zeolit A". Other molecular sieves that have been synthesized include zeolite B, F, G, H, K-G, J, L, NI, K-NI, Q, R, S, T, U, Y and Z.

Zeolite X and a process for its preparation are described in more detail in the disclosure to U.S.A. No. 2,882.

244. The general formula for Zeolite X, expressed in molar fractions of oxides, is as follows: (0.9 ± 0.2) Nl 2 O: AlGO 2: (2.5 + 0.5) SiO 2: (0-8) HgO. n In the formula, M denotes a metal and n its valence. As noted above, the zeolite is activated or enabled to adsorb certain molecules by removal of water from the crystal, such as by heating. Thus, the actual number of moles of water present in the crystal will depend on the degree of dehydration or activation of the crystal.

The metal represented in the above formula by the letter M can be exchanged by commonly known ion exchange technique. The sodium form of Zeolite X, referred to as sodium zeolite X or simply a NaX molecular sieve, is the most convenient to make. For this reason, the other forms of Zeolite X are usually obtained by modification of Sodium Zeolite X.

A typical formula for sodium zeolite X is: 0.9 Na 2 O: AlgOg: 2.5 SiO 2: 6.1 H 2 O.

Removal of at least some of the water from sodium zeolite X activates the material and prepares it for filling with carbon dioxide.

The main lines of the X-ray diffraction pattern of sodium zeolite X are given in Table A below.

Table A

d-value for reflection in Å 100 l / lQ

14.42 + 0.2 ”TUO

8.82 + 0.1 18 4.41 ± 0.05 9 3.80 + 0.05 21 3.33 ± 0.05 18 6 147273

d-value for reflection in Å 100 l / lQ

2.88 ± 0.05 Ϊ3 2.79 ± 0.05 8 2.66 ± 0.05 8.

To obtain the X-ray diffraction powder patterns, standard procedures are used. The radiation is the K duplicate of copper, and a Geiger counter spectrometer with a strip printer is used. The peak values I and the positions as a function of 2Θ, where Θ is the Bragg angle, are read by the spectrometer strip. From these results, d (obs. Distance between planes) is calculated in Å corresponding to the recorded lines. The X-ray patterns indicate a cubic unit cell with dimensions between 24.5 Å and 25.5 Å.

To prepare sodium zeolite X, the reactants are mixed in aqueous solution and maintained at ca. 100 ° C until the crystals of Zeolite X are formed. The reactants should preferably be such that the solution has the following weight ratios:

SiO2 / Al2 O3 3-5

Na 2 O / SiO 2 1.2-1.5 H 2 O / Na 2 O 35-60

The way in which Zeolite X can be obtained is illustrated by the following: 10 g NaA100, 32 g of an aqueous solution containing approx. 20% by weight Na 2 O and 32 wt% SiO 2, 5.5 g NaOH and 135 cm H 2 O are mixed and kept in an autoclave for 47 hours at approx. 100 ° C. Crystalline sodium zeolite X is removed by filtration of the reacted substances and washed with water until the pH of the wash water is between 9 and 12. The crystals are then dried at least partially.

Zeolite A and processes for its preparation are described in the disclosure to U.S.A. Patent No. 2,882,243. The general formula for Zeolite A, expressed in molar fractions of oxides, is as mentioned: (1.0 ± 0.2) M 2 O: Al 2 O 3: (1.85 ± 0.5) SiC> 2: (0-6) HgO. n In the above formula, M is a metal, hydrogen or ammonium, and n is the valence of M. The amount of H 2 O present in Zeolite A will, of course, depend on the degree of dehydration of the crystals.

As was the case with Zeolite X, the portion of the molecule designated M in the above formula can be altered by conventional ion exchange technique. Sodium Zeolite A is the most convenient form to prepare, and other forms are usually obtained from it by the exchange of ions in aqueous solutions. A typical composition of sodium zeolite A is: 0.99 Na 2 O: 1.0 Al 2 O 3: 1.85 SiO 2: 5.1 HgO.

Removal of at least a portion of the water, such as by heating, will be sufficient to activate sodium zeolite A and prepare it to be filled with carbon dioxide.

Using the same technique by which X-ray diffraction data for sodium zeolite X were obtained, corresponding data for sodium zeolite A are obtained and these will be shown in Table B.

Table B

d-value for reflection in Å 100 l / lQ

12.2 + 0.2 100 8.6 + 0.2 69 7.05 ± 0.15 35 4.07 ± 0.08 36 3.68 ± 0.07 53 3.38 ± 0.06 16 3.26 ± 0, 05 47 3.96 ± 0.05 55 2.73 ± 0.05 12 2.60 ± 0.05 22

In the preparation of sodium zeolite A, the reactants are mixed in aqueous solution and maintained at ca. 100 C until crystals of Zeolite A. have been formed. The reactants must be of such a nature that the following conditions are present in the solution:

SiO2 / Al2 O3 # 1.2 - 2.5

Na2 O / SiO2 "0.8 - S, O H2 O / Na2 O 35 - 200

An example of a manner in which sodium zeolite A can be prepared is the following: 80 g of NaAIC> 2, 126 g of an aqueous solution of sodium sulfate containing ca. 7.5% by weight Na50 and 25.8% by weight SiO2 and 320 cm H2 O are placed in an autoclave. In the autoclave, the following ratios are present: SiOg / AlgOg = 1.2; Na 2 O / SiO 2 = 1.2; and H20 = 36. The content of the autoclave is kept at approx. 100 ° C for approx.

12 hours. Crystalline sodium zeolite A is obtained by filtration and washing with distilled water until the wash water has a pH of between 9 and 12. After drying and at least partially dehydrating, the crystals are ready for use in the present invention.

These and other types of crystalline aluminum silicate molecular sieves useful in the present invention are discussed in more detail in the following literature: Hersh, "Molecular Sleves11, 1961; Thomas and Mays," Separations with Molecular Sieves "in" Physical Methods in Chemical Analysis ", Volume IV, pages 45-97, 1961; Breck," Crystalline Molecular Sieves "in" Journal of Chemical Sieves ", a technical publication of the Union Carbide Corporation.

Several special types of molecular sieves are particularly suitable for use with the apparatus of the invention. The following description refers to molecular sieves in the form of "types", all of which are materials obtainable from the Molecular Sieve Department,

Union Carbide Corporation. Generic terms such as NaA, NaX,

CaA, CaX represent sodium zeolite A, sodium zeolite X, calcium zeolite A, calcium zeolite X, respectively. These include type 4A and 13X molecular sieves. Type 4A (NaA) has a pore size of 4 Å and can be characterized by the following chemical formula:

Na 12 [(AL02) 12 (Si02) 12] -27H20.

Type 13X (NaX) has a pore size of 10 Å and can be characterized by the following chemical formula:

Nag6 [(A102) g6 (SiO2) 106] -276H2O.

In both the type 4A and type 13X molecular sieves, the sodium ions can be exchanged with other cations, such as potassium and calcium, to provide other pore sizes and somewhat different adsorption properties. Eg. gives the type 4A molecular sieve, where approximately 70% of the sodium cations are exchanged with calcium cations, a molecular sieve commercially marketed by Union Carbide Corporation as type 5A (CaA) with a pore size of 5 Å. Similarly, type 13X (NaX) molecular sieve is marketed at approx. 70% of the sodium cations yielded calcium cations commercially by Union Carbide Corporation as type 10X (CaX) with a pore size of 8 Å. Another molecular sieve (type 3A) has a potassium zeolite A (KA) structure and a pore size of 3 Å.

It is also commercially possible to obtain crystalline aluminosilicate molecular sieves classified as "acid resistant". Acid-resistant molecular sieves are crystalline zeolites that are not structurally degraded and from which metal ions are not washed out by prolonged contact with low pH solutions. Side acid resistant molecular sieves are usually prepared by removing or replacing many of the exchangeable metal ions found in natural and synthetic molecular sieves with protons. This is accomplished by first exchanging metal ions with ammonium ions and then heating the resulting ammonium form of these molecular sieves to ca. 400 ° C to decompose the ammonium cations. Although the exchangeable metal ions in all crystalline metal aluminum silicates can be removed or replaced to some extent by this process, in most cases a complete ion exchange of this type of zeolite crystal structure destroys. To replace more than 35¾ of the zeolite metal ions without destroying the aluminum silicate crystal, the zeolites having a SiC 2 / AlgOg molar ratio greater than 3: 1 are used by the above ion exchange methods. Zeolites having such a high SiOg / A ^ And molar ratio include the natural mineral faujasite and the synthetic sodium "Zeolite Y" (NaY), which is described in greater detail in the U.S.A. specification. Patent No. 3,130,007. Zeolite Y has the general formula (0.9 + 0.2) of Nag C ^ AlgOg / CSiOg / dHgO, where c ranges from 3 to 6, and d (before dehydration) is less than or equal to 9. The method of reducing the metal ion content in crystalline metal aluminum silicates are described in more detail in the descriptions for the United States patents Nos. 3,130,006 and 3,460,904.

Examples of commercially available acid resistant molecular sieves prepared by the metal ion removal method described above include the type AW-300 molecular sieve having a pore size of 4 Å, the type AW-500 molecular sieve having a pore size of 5 Å, type SK40 (NaY in particulate form with a clay binder) and type SK41 (NaY in particulate) molecular sieves, both having a pore size of 8-10 Å, and the Zeolon series 100, 200 and 900 currently marketed by the Norton Company.

Various molecular sieve shapes with particle sizes ranging from powder (0.5-12 microns) to spheres of 6.4 mm diameter are commercially available, most of the non-powdered forms containing an inert clay binder. to an extent of 20% by weight. Common molecular sieves include extruded pellets of 1.6 mm and 3.2 mm diameter and bullets that will pass through an 8 mesh screen but not through a 12 mesh screen. Molecular sieves can be imparted to other forms of any size or shape, if desired with clay or polymer resin binders.

10 147273

As mentioned, carbon dioxide is absorbed in the aluminum silicate material for use in the apparatus of the invention. Carbon dioxide is strongly adsorbed on these sieves but easily displaced through the stronger and preferred adsorption of water. Accordingly, the release of adsorbed carbon dioxide from molecular sieves in aqueous solution forms the basis of the carbonic acid addition of the apparatus of the present invention.

Molecular screens are "filled" with carbon dioxide simply by contacting the activated (i.e., at least partially dehydrated) screen material with gaseous carbon dioxide under anhydrous conditions to produce carbon dioxide adsorption. The screen materials can typically be dehydrated to approx. 2% by weight of water. Molecular sieves are preferably charged with carbon dioxide in a column with a packed layer through which the gas is passed at room temperature and a low positive pressure (up to 1.07 kg / cm). As mentioned, the molecular sieves must be "filled" to an extent of at least approx. 5% by weight (i.e. weight of adsorbed cow I dioxide / weight of filled screens x 100%). The extent to which a special size is aimed, i.e. sieves having a specific pore size, adsorbing carbon dioxide at a given temperature or pressure, are readily determined by experiment or by using adsorption data provided for commercially available sieves.

It is important that the carbon dioxide filled molecular sieves are packaged and stored in a manner that prevents contact with atmospheric moisture prior to their use in the apparatus of the present invention. Such atmospheric humidity will displace carbon dioxide and render the screens ineffective in connection with carbonic acid addition. for drinks.

When the carbon dioxide-filled molecular sieves of the apparatus of the invention are contacted with aqueous potable liquid, carbon dioxide is released from the sieves as a result of the preferred adsorption of water from the beverage solution. A carbonated beverage is obtained when the released carbon dioxide is dissolved in the aqueous liquid. Subsequent release of the dissolved carbon dioxide into the mouth upon ingestion of the drink produces the distinctive feeling and taste of a carbonated beverage. The extent of carbon dioxide addition, of course, increases as the more carbon dioxide dissolves. Carbon dioxide addition is usually measured in a unit which will hereinafter be referred to as "volume of dissolved CO2" or "volume of carbon dioxide addition" defined as the gas volume (reduced to standard condition, i.e. 760 mm Hg and 0 ° C) which at the temperature and pressure of the carbonic acid addition are dissolved in a given volume of beverage.

For the purpose of assessing various carbon dioxide additives, another carbon dioxide addition indicator, which is referred to as the performance factor Pn, must be mentioned, which is defined and expressed by the following formula:

Pn = (A) (B) η η n where A „is an efficiency factor defined by the ratio: n '

Volume C02 dissolved under carbonic acid addition for n minutes Volume dissolved C02 at saturation and Bn is an efficiency factor defined by the ratio:

Volume C02 dissolved by carbonic acid addition for n minutes Total volume C02 available in the sieves used

The performance factor combines the fraction of obtained saturation (efficiency) with the efficiency of carbonic acid addition for a given period of time. In the most ideal case, An would be 1 if a saturated solution was produced and greater than 1 if saturation was obtained.

Bn would be 1 if all the carbon dioxide present dissolves.

Therefore, the greater the performance factor, the more a given molecular sieve carbonic acid addition system is preferred. This performance factor is used to identify and assess significant screening parameters and beverage solution properties.

The solubility of carbon dioxide in aqueous solution is largely a function of temperature and pressure. Solubility data at various temperature and pressure conditions can be readily determined from the known literature. Thus, there are certain temperature and pressure limitations for the carbonic acid addition. The solubility of carbon dioxide in pure water approaches 0.5 volumes of dissolved CO 2 (low carbonated beverage) at approximately 43 ° C and 1 atmosphere. Accordingly, carbonic acid addition temperatures above 43 ° C are not desirable using the apparatus of the present invention. There is no theoretical lower temperature limit for the carbonic acid addition, but of course there is a practical lower limit in the form of the freezing point of the particular aqueous beverage solution added to carbonic acid. A highly preferred carbonic acid addition temperature is the temperature of an icy beverage mixture, i.e. about 0 ° C.

In a similar manner, carbon dioxide addition with molecular sieves becomes unacceptably ineffective at carbon dioxide addition pressures below 1 atmosphere. Carbon dioxide addition pressure of over 1 atmosphere increases carbon dioxide solubility and makes carbon dioxide addition to beverages particularly effective. With the apparatus of the invention, the carbonic acid addition is preferably carried out in closed containers where pressure of up to approx. 10 atmosphere. However, from a practical point of view regarding carbon dioxide addition in the home or at the time of use, atmospheric pressure, i.e. carbonic acid addition in an open container.

The carbonic acid addition is important in many applications, but it is not a critical variable in connection with the apparatus of the invention. The period of contact of the filled molecular sieves with the beverage will, of course, vary depending on the amount of liquid present, its nature, the amount, type and content of the molecular sieves used, and the "strength" desired for the carbonated beverage. . By using carbon sieves filled with carbon dioxide to an extent of at least 5% by weight and by carrying out the carbonic acid addition at appropriate temperature and pressure conditions as described above, suitable carbonated beverages can be obtained after periods of time typically in the home range of 2%. and 15 min. Carbon dioxide addition systems that provide carbon dioxide release for longer or shorter periods of time can typically be obtained by using the preferred embodiments of the apparatus of the present invention, discussed further below.

Changing the pore size in the molecular sieves used in the apparatus of the present method affects both the carbonation rate and the final carbonation rate.

This is seen from the typical data shown in FIG. 1. The performance factor at a typical carbonic addition time (4 minutes) generally increases with increasing pore size, as shown in FIG. 2. The curves of FIG. 1 and 2 are representative of data obtained from 3 screened experiments with carbonic acid addition to 236 cm cold water at atmospheric pressure using different amounts of molecular sieves types 3A, 4A, 5A, 10X and 13X with pore sizes respectively of 3, 4, 5, 8 and 10 Å. Each sieve type was filled with carbon dioxide to the maximum extent, using pre-activated sieve in fact; more specifically, containing 7.9, 10.8, 11.7, 10.9 and 13.2% by weight. As can be seen, the larger screen types, especially those with a pore size of 8-10 Å, exhibit a larger "four minute performance factor" (P 1), and these are thus preferred.

As might be expected, the amount of carbon dioxide released by increasing the amount of molecular sieves used for a given amount of beverage solution, although the carbon dioxide addition efficiency clearly decreases with an increase in the total amount of molecular sieve present. Although the optimum amount of molecular sieve used varies depending on the properties of the sieve used and the beverage solution to be added to carbonic acid, the preferred amount of molecular sieve is from approx. 0.5 to approx. 4 g

ISLAND

(before filling) molecular sieve per 29.6 cm beverage to be added carbon dioxide.

The physical shape or shape of the molecular sieves used may also affect the carbonic acid addition. Powdered molecular sieves are preferably used, and these sieves are given a suitable shape having a high surface area-to-volume ratio.

This can be accomplished by using porous binder systems to mold or extrude the sieves into such shapes as pellets, bullets or thin slices. Methods for bonding or forming molecular sieves are well known and are e.g. described in the descriptions of U.S.A. patents Nos. 3,158,597 and Nos. 3,213,164, British Patent Nos. 994,908 and Belgian Patent Nos. 627,185.

Mixtures of molecular sieves can be used to achieve particularly desired properties. Generally, molecular sieve types with smaller pore size (3-5 Å and especially 3-4 Å) release carbon dioxide upon contact with water more slowly, but continue to release it for a longer period of time. Molecular sieves with larger pore openings (greater than 6 Å) provide relatively high initial release rates for carbon dioxide, but such release is not sustained for a long time.

The ability of an aqueous solution to dissolve carbon dioxide is inversely proportional to its degree of saturation. During an initial carbon dioxide addition, carbon dioxide can dissolve at a relatively large rate, while the velocity becomes smaller as the solution approaches saturation. When systems with both large initial carbon dioxide release and long-term carbon dioxide solution are desired, such can be achieved by using mixtures of sieves with varying pore sizes. In a preferred long-term carbon dioxide additive apparatus, a mixture of molecular sieves is used, wherein 30 to 70% by weight of the sieve mixture consists of sieves having a pore size of from 3 to 5 Å and preferably 3 to 4 Å, while the rest of the molecular sieves used have pore sizes of from approx. 6 to 10 Å.

In some apparatus, it may be desirable to use a mixed molecular sieve / chemical reaction pairing system. Chemical reaction pairs are usually cheaper per minute. volume of released carbon dioxide than molecular sieves. The flavors of the salts of carbon dioxide releasing chemical reaction pairs, when present in small amounts, are not or only noticeably noticeable. Noticeability depends on the chemical constituents of the reaction pair, the flavors of the beverage and the sensitivity of the consumer. Typically, approx. 0.5 to 0.75 volumes of dissolved carbon dioxide (beverages with low carbonation) for a carbonated cola drink by means of a chemical reaction pair, without giving up undesirably high salts (i.e., quantities which give a noticeable taste). Accordingly, an appropriate way to obtain carbonic acid addition is to use a small degree of carbonic acid addition with chemical reaction pairs supplemented with carbonic acid addition by molecular sieves. In such a mixed system, the molecular sieves will preferably be of the smaller pore size species (i.e., ca.

3 to 5 Å) for slow release to supplement the reaction pair giving rapid release.

The type of beverage to be added to carbonic acid by the apparatus of the present invention is not critical. As mentioned, the drink must be of a watery nature. Such liquids may contain, in addition to water, any type of non-interfering flavoring, coloring agent, food additive, medicine or alcohol.

Such substances can, in a dry state, possibly. be packaged in the apparatus of the invention to produce a tasty carbonated beverage simply by the addition of tap water. As a further option, flavors and dyes may be provided in an aqueous mixture, which is added to water and then brought into contact with the carbon dioxide filled sieves of the apparatus of the invention.

Examples of the types of beverages that can be prepared from appropriate liquids by carbonic acid addition with the apparatus of the present invention include non-alcoholic beverages, medicinal preparations, beers and sparkling wines.

However, certain solvents that may be present in beverage solutions may affect the carbon dioxide solution, but certain measures may be taken in the case of such solvents. Artificial sweeteners such as saccharin and saccharin-containing agents have been found to have little effect on the carbonic acid addition, but various natural sweeteners inhibit the rate and extent of carbonic acid addition by molecular sieves. Eg. inhibits fructose, sucrose and glucose in amounts similar to the amount in typical non-alcoholic beverages to a noticeable degree carbonated additives for beverages containing them. However, it has been surprisingly discovered that by carbonic acid addition to solutions containing fructose or glucose, 10 Å molecular sieves in the form of 4x8 mesh spheres provide a much higher rate of carbonic acid addition than to similar solutions containing sucrose.

The presence of the common edible acidic constituents, such as citric acid, up to a volume of approx. 1% has been found to have very little effect on the rate or extent of the carbon dioxide addition by molecular sieving technique. However, such edible acid-containing beverages are necessarily solutions of relatively low pH (for example, a 1% aqueous citric acid solution has a pH of 2). Prolonged contact between such solutions and many synthetic molecular sieve materials will result in a gradual leaching of metal ions from the sieve material. As a result, the effect of pH in such beverages can be increased to such an extent that noticeable taste changes occur. Accordingly, when beverages containing edible acids are added carbonic acid with the apparatus of the present invention, it is preferred to use acid resistant molecular sieves as described above, i.e. crystalline metal aluminum silicates having a SiC 2 / AlgOg molar ratio of at least 3 and wherein at least 35% of the exchangeable metal ions have been removed or replaced with protons.

When carbon dioxide is released rapidly in the solution from molecular sieves, it usually does not dissolve as efficiently as at lesser release rates. Smaller release rates generally provide better gas-liquid contact and therefore promote carbon dioxide solution. Thus, resolution can generally be improved by using various means to control the rate of carbon dioxide release from the molecular sieve material. As noted above, one method is to reduce the rate of carbon dioxide displacement of water from molecular sieves in that at least some molecular sieves with pore sizes of from 3 to 5 Å are used. Other measures to regulate and reduce the carbon dioxide release rate from molecular sieves include coating the sieves with a water-soluble material that inhibits the water entry into the carbon dioxide-containing molecular sieve channels by dissolving the coating. Any non-toxic water-soluble coating compound such as vinyl alcohol, polyvinylpyrrolidone or hydroxypropyl cellulose is suitable. The readily available hydroxypropyl cellulose is the preferred coating agent.

As noted above, carbon dioxide release rate can also be regulated by using different kinds of molecular sieves.

Change in the volume / surface ratio of the aluminum silicate material has a noticeable effect on the carbon dioxide displacement from the molecular sieves. Generally, sieves with a larger volume / surface area ratio release carbon dioxide more slowly and over a longer period than sieves with a lower volume / surface area ratio.

The carbonic acid addition of the apparatus of the present invention is recaptured as mentioned by contacting the molecular sieves of the apparatus with a liquid. Generally, the liquid to be added carbon dioxide is added in sufficient quantity to cover at least the sieves. In order to avoid the necessity of filtration or filtration, the molecular sieve material is provided attached to the inner side of the container of the invention. The container, containing carbon dioxide filled sieves, can only be used for beverages containing flavorings or in connection with a variety of flavorings and additives to which only tap water or the like must be added.

An embodiment of the apparatus according to the invention is designed such that the molecular sieve material itself forms part of a beverage container. For this purpose, for example, standard drinking containers which have attached to their internal surface may have powdered, pelleted or spherical molecular sieves may be used. Generally, the sieves are distributed over the area of the inner surfaces which, when the container is filled with liquid, will be brought into contact with the liquid beverage. By distributing the molecular sieves in this way, the carbon dioxide in the solution is released in many different places. The carbon dioxide bubbles thus move through a large volume of liquid, which greatly improves the solution in the beverage.

U7273 17

Attachment of the screens can be accomplished using any inactive, insoluble adhesive such as paraffin or epoxy resins. If the beverage container as such is made of plastic, the screens can be adhered to the heat softened inner surfaces of the container and fixed by cooling. Such beverage containers, in addition to the molecular sieve material, may also contain a beverage-dry mixture of flavors and dyes, whereby it is possible to produce full-tasting, carbonated beverages only by the addition of tap water.

An example of this embodiment of the apparatus according to the invention is shown in FIG. 3. Beads of molecular sieve material 20 are adhered or otherwise attached to the inner surface 21 of a drinking beaker or container 22.

Molecular sieves can also be attached directly to beverage containers by first molding the seed material into solid bodies that correspond to the shape of the containers and, when attached to the interior of the containers, have surface area covered and contacted with a liquid beverage. The preparation of such shaped screen parts using inert clay binder or polymer resins is well known in the art as discussed above.

The parts can as such be attached to the inner surface of the beverage container using an inactive, insoluble adhesive or by using such containers whose shape or shape is of such a nature as to hold the shaped screen parts in place below the surface of a contained container. beverage. By varying the thickness of the sieve portions between about 0.025 mm and 7.5 cm, containers can be produced which, when filled with liquid, produce different amounts of carbonic acid addition. Here again, the beverage container may also contain a beverage-dry mixture.

An example of this embodiment of the apparatus according to the invention is shown in FIG. 4. A disc of bonded molecular sieve powder 30 is placed at the bottom of a flexible beverage container 31 and held in place by an insoluble adhesive or simply by pressing the disc into the bottom of a tapered elastic cup.

The following examples serve to illustrate the apparatus of the present invention for its use and carbonization ability. In each of the examples, carbonic acid is added to a sample of a potable liquid using molecular sieves filled with carbon dioxide. All of the molecular sieves used are "filled" in a column of packed layers through which carbon dioxide has been passed at room temperature and a pressure of approx. 1.04 kg / cm. In the examples, the amount of carbon dioxide currently dissolved in a given liquid sample is determined gravimetrically by expelling the carbon dioxide of the solution by heating and passing it with a nitrogen-washed reading stream to an absorbent layer of Ascarite which is commercially available sodium hydroxide on an asbestos substrate.

Example I

Several samples, each in 236 cm of pure water, were added carbon dioxide with varying pore size molecular sieves. All molecular sieves used were in the form of molded particles containing clay binders. Carbonic acid addition in each case took place in a 400 ml beaker at a temperature of 2.2 ± 0.6 ° C in an ice bath. The particular types of sieves used, the extent to which they were filled with carbon dioxide and the amount of sieves used are summarized in Table 1 below.

Table 1

Sieve type Pore size Average filling size (Å) scope (weight COg / weight of quantity, filled screens x 100%) g

Type 3A 3 8.5 24

Type 4A 4 12.1 12

Type 5A 5 13.4 12

Type 10X 8 14.1 12

Type 13X 10 15.9 12

The size of the added volume of carbonic acid obtained after 1, 2, 3, 4, 6, 10 and 20 minutes was determined by separate carbonic acid addition experiments. The results obtained are the basis of FIG. 1 and is summarized in Table 2 below.

147273 19

Table 2

Sieve type Pore size Carbon dioxide additive Carbon dioxide addition (Å) time (minutes) volume per volume of water 3A 3 1 0.146 3 0.300 6 0.360 10 0.750 20 0.595 4A 4 1 0.212 3 0.307 6 0.826 10 0.560 20 0.795 5A 5 1 0.682 2 0.767 4 0.672 0.643 10 0.743 10X 8 1 1,210 2 1,230 4 1,180 6 1,120 10 1,200 13X 10 1 1.30 2 1.31 4 1.38 10 1.31

Virtually similar results are obtained when the type 4A molecular sieves of Example I are replaced with acid resistant type AW-300 molecular sieves and type 5A molecular sieves are replaced with acid resistant type AW-500 molecular sieves.

20

Example II

"4 minute performance factors" for 12 and 24 g portions of 3, 4, 5, 8, and 10 Å pore size molecular sieves were calculated by carrying out carbonic acid addition to water according to the procedure described in Example 1 above. cases filled with carbon dioxide to the extent shown in Table 1 above. 2 and is summarized in Table 3 below.

Table 3

Sieve pore size 114 minutes performance factors11 (Å) - 12 g pre-filled sieve 24 g pre-filled sieve 3 0.023 4 0.075 0.073 5 0.116 0.141 8 0.307 0.210 10 0.347 0.233

Example III

A 13X molecular sieve in the form of spheres capable of passing an 8 mesh screen but not a 12 mesh screen and loaded with carbon dioxide to an extent of 15.9% by weight was used to add carbon dioxide to water in accordance with the procedure described in Example 1 above. 6 grams, 12 grams and 24 grams samples were used and the volumes of added carbonic acid obtained were recorded for each sample under separate carbonic acid addition experiments after 1, 2, 4, 6 and 10 min. of carbonic acid addition. The results of this carbonic acid addition are summarized in Table 4 below.

Table 4

Duration Volume of carbon dioxide per volume of water (minutes) 6 g portion 12 g portion 24 g portion 1 0.77 1.10 1.40 2 0.91 1.32 1.54 4 0.99 1.32 1.95 6 0.98 1.47 1.37 10 0.95 1.47 1.77 147273 21

Example IV

The molecular sieve mentioned in Example III was again used to add carbonic acid to water according to the method of Example III.

"4 minutes efficiency factors", efficiency factors and performance factors were recorded for a 6 gram, a 12 gram and a 24 gram portion of molecular sieves filled with carbon dioxide to an extent of 15.9% by weight. These results are summarized in Table 5 below.

Table 5

Comparison of "4 minute performance factors" for different portions of 13X type bullets.

Quantity Quantity per. Efficiency Efficiency Performance (Grams) Unit Solubility Factor (B ^) Factor (P ^) (A4) (g / 29.6 cm3) 6 0.75 0.611 0.521 0.318 12 1.5 0.855 0.363 0.310 24 3.0 0.994 0.212 0.211

Examples III and IV show that although more carbon dioxide is released into a solution by using larger amounts of sieves, the carbon dioxide addition efficiency clearly decreases with an increase in the total amount of sieves present. Therefore, performance factors are optimized by using from approx. 0.75 to 1.5 g molecular sieve per

3 29.6 cm beverage.

Example V

Several types of the type 13X molecular sieves, i.e. 1.6 mm and 3.2 mm pellets and two kinds of bullets, namely bullets that can pass an 8 mesh sieve but not a 12 mesh sieve, and bullets that can pass a 4 mesh sieve but not an 8 mesh sieve and filled with Carbon dioxide was used in carbonic acid addition to water according to the procedure described in Example I. Carbon addition volumes after 1, 2, 4, 6 and 10 minutes (separate carbonic acid addition experiments) were determined and the results summarized in Table 6 below were determined. achieved.

Table 6 22 147273

Carbon dioxide addition time- Volume carbon dioxide addition per volume water space (minutes) 1.6 mm's 3.2 mm's 8/12 4/8 pellets 1) pellets 2) bullets 3) bullets 4) 1 1.30 1.06 1.10 0.90 2 1.31 1.21 1.32 1.38 4 1.38 1.51 1.32 1.67 6 1.01 1.30 1.47 1.55 10 1.31 1.36 1.47 1 , 52 1) Filled with 13.2% CO 2 · 2) Filled with 13.7% CO 2 · 3) Filled with 14.8% CO 2 -4) Filled with 15.2% CO 2.

Virtually similar carbonic acid addition results are obtained when the molecular sieves used are the type 13X powder form.

Virtually similar carbonic acid addition results are obtained when acid-resistant molecular sieves having a pore size of 10 Å and having a SiO 4 and with 40% of the exchangeable metal ions removed or replaced with protons are used.

Example VI

The effect of carbonic acid addition with a mixture of molecular sieves having a pore size of 4 and 10 Å, respectively, was demonstrated by using such a mixture with carbonic acid addition to water according to the method and the CO 2 fill contents of Example I. Carbon addition profiles are obtained using 24 g sieves ( 4 Å), 24 g sieves (10 Å) and a mixture of 12 g sieves (4 Å) and 12 g sieves (10 Å), all sieves having the shape of the above 8/12 mesh balls. The resulting carbonic acid addition profiles clearly show that the sieve mixture provides greater initial carbon dioxide release and solution than the 4 Å sieves, but after approx. 10 minute carbon dioxide addition contains solutions that are added to carbon dioxide to a much greater extent than those obtained with 10 Å sieves alone.

Example VII

Type 13X molecular sieves in the form of 8/12 spheres and filled to a level of 15.9 wt.% By 15.9% by weight of carbon dioxide were used to add carbon dioxide to sweetened solutions to show the effect of carbonic acid addition in conjunction with dissolved sweeteners in a beverage liquid.

A 10% sucrose solution, a 10% fructose solution, a 1.45% artificial sweetener (Poly Sweet R, a saccharin based material currently commercially available from the Guardian Chemical Corporation) - solution and pure water were added to carbon dioxide in accordance with the procedure of Example I. Carbon addition profiles for these four solutions are summarized below in Table VII.

Table VII

Carbonic Acid - Purely 10% sucrose - 10% fructose - 1.45% Poly

phrase water solution solution Sweet R

time resolution (minutes) 1 1.10 0.26 0.53 1.17 2 1.32 0.61 1.06 1.26 4 1.32 1.30 1.52 1.39 6 1.47 1, 27 1.36 1.50 10 1.47 1.43 1.35

The above seven examples clearly show the efficacy of crystalline aluminum silicate molecular sieves in connection with beverage antacid addition over a wide variety of sieve sizes, sieve quantities, sieve shapes, sieve mixtures and beverage solutions.

The following examples illustrate embodiments of the apparatus of the invention.

Example VIII

A carbon dioxide addition device is designed as follows:

A polystyrene container with a volume of approximately 400 ml is softened by heating. Molecular screens of the type 13X and having a particle size of 5 microns are adhered to the softened inner surfaces of the plastic container sufficiently to cover these surfaces. The container is allowed to cool, whereby the hardened plastic anchors the screens. The entire container is then contacted with carbon dioxide to fill the molecular sieve powder to an extent of approximately 20 weight percent of the sieves. When liquid to be added carbon dioxide is poured into the container over ice, it is supplied with carbon dioxide to the extent of about 1 volume of dissolved carbon dioxide per volume of water.

Almost similar results are obtained when the powdered molecular sieves are replaced by 4x8 mesh spheres of the 13X molecular sieves attached to the inner surfaces of the beverage container shown in FIG. Third

Example IX

A carbon dioxide addition device is designed as follows:

At the bottom of a cylindrical polystyrene container similar to that described in Example VIII, a cylindrical disc formed of 13X powdered molecular sieves is placed. This disc is attached to the bottom of the polystyrene container as shown in FIG. 4th

The shaped molecular sieve disk is then filled with carbon dioxide to an extent of approximately 20% by weight of the disk. When liquid is poured into the container, it is supplied with carbon dioxide to the extent of about 1 volume of dissolved carbon dioxide per volume of water. The flat disc provides large initial carbon dioxide release from the sieve material near its upper surfaces and also provides continued carbon dioxide release from the sieve material located further inside the disc. The initial carbon dioxide release is inhibited if the disc prior to being placed in the container is coated with a poly vinylal carbon film.

Example X

A tablet made of 13X molecular sieves containing 20% by weight of clay binder and pressed into a 38.1 mm diameter disk weighing 11.47 g, filled with COg (16.04% CO 2) was placed in a 400 ml beaker containing 236.6 cm 3 of water at 1.7 ° C. After 4 minutes, a carbon dioxide addition of 1.22 volumes per volume of water was measured.

Carbon dioxide deposition exceeding approx. 2 volumes can be obtained if the carbonic acid addition takes place in a closed container and if the pressure during the carbonic acid addition is allowed to rise to about 3 atmospheres.

A wide variety of dry flavors, dyes and additives can be used in conjunction with the apparatus of the invention, so that, when water is added, full-flavored carbonated beverages are formed. Such flavors, dyes and additives are designated

Claims (3)

147273 as beverage dry mixes. Typical ingredients in such blends may include flavors, either natural or artificial, such as cola, lemon, lime, orange, grapefruit, cherry, root beer, beer, ginger ale, wine, tea, coffee, etc .; dyes, especially when artificial flavors are used; sweeteners, either natural or artificial, such as glucose, fructose and sucrose (the former two being preferred over the latter due to the previously mentioned effect on the carbonic acid addition rate), saccharin (presenting less inhibition of the carbonic acid addition rate with the natural carbonic acid additives) than the natural carbonic acid additives. . Various other additives well known in the beverage field, such as thickeners or preservatives, may also be added. A highly satisfactory way of providing carbonated beverages at the time of use is to package an agent consisting of a beverage-dry mixture of any of the above types into a closed container of carbon dioxide filled molecular sieves of the invention. Carbon dioxide addition apparatus for beverages comprising a water-impermeable container (22, 31), the inside or inside of which (21) of which is attached a carbon dioxide releasing material, characterized in that the carbon dioxide releasing material is a porous crystalline aluminum silicate material (20,30 ) selected from a group consisting of Zeolite X, Zeolite Y, Zeolite A and Faujasite, with pore sizes of from 3 to 10 Å, where at least 5% by weight of carbon dioxide is absorbed in the aluminum silicate material and attached to the container is applied a sufficient amount of aluminum silicate material to obtain from 17 to 135 g of crystalline material per minute. liter capacity of the container. Apparatus according to claim 1, characterized in that the crystalline aluminum silicate material comprises granules forming a liner (20) which adheres to or is bonded to the inner faces (21) of the container (22). Apparatus according to claim 1 or 2, characterized in that the crystalline aluminum silicate material comprises a single molded block (30) having a thickness of from 0.025 mm to 7.5 cm fixed within the container (31).