JP7804833B2 - Containerized carbonated beverage, its manufacturing method, and method for preventing gas leakage from containerized carbonated beverage - Google Patents

Description

The present invention relates to a bottled carbonated beverage, a method for producing the same, and a method for preventing gas leakage from a bottled carbonated beverage.

Carbonated drinks are widely enjoyed as beverages that offer a refreshing sensation due to the stimulation of carbon dioxide gas when consumed. Generally, carbonated drinks are designed with the flavor of carbon dioxide gas as a prerequisite. However, with conventional bottled carbonated drinks, after the container is opened, the carbon dioxide contained in the drink gradually decreases over time, a phenomenon known as "out-gassing," resulting in a weakening of the stimulation caused by the carbon dioxide gas. In particular, when bottled in large containers, out-gassing is more likely to occur due to the longer time required for consumption. Carbonated drinks that have out-gassed not only experience a decreased refreshing sensation, but also have the problem of altered flavor, such as a stronger sweetness, due to the reduced stimulation of the carbon dioxide gas. Various technologies are being investigated to prevent this out-gassing.

For example, Patent Document 1 proposes suppressing gas leakage from bottled carbonated beverages by using an emulsifier containing a polyglycerol fatty acid ester in combination with a flavoring containing a specific hydrophobic component.

Patent document 2 also states that the loss of carbon dioxide gas can be suppressed by adding specific polyphenols and specific sweeteners.

Patent document 3 also describes that adding indigestible dextrin to a carbonated beverage makes it easier for carbon dioxide gas to escape from the beverage, and that adding pectin and collagen to the carbonated beverage can prevent carbon dioxide gas from escaping.

Japanese Patent Application Laid-Open No. 2017-012016 JP 2017-123788 A Japanese Patent Application Laid-Open No. 2021-153412

However, the methods described in Patent Documents 1 to 3 have the limitation that they can only be applied to beverages that have flavors that match specific flavorings, sweeteners, or additives. Furthermore, the above-mentioned conventional methods leave room for further improvement in terms of suppressing gas leakage from carbonated beverages.

Therefore, the present invention aims to provide a bottled carbonated beverage in which gas leakage is suppressed.

The present inventors conducted extensive research with the aim of solving the above-mentioned problems. They then discovered that adding a certain concentration or more of killed beneficial bacteria to a bottled carbonated beverage can prevent gas leakage from the bottled carbonated beverage, leading to the completion of the present invention.

That is, the present invention aims to advantageously solve the above-mentioned problems, and the present invention relates to [1] a bottled carbonated beverage containing killed beneficial bacteria, having a killed beneficial bacteria concentration of 500 million/L or more, and further, a gas pressure of 0.05 MPa or more and 0.5 MPa or less. Within the above gas pressure range, if the killed beneficial bacteria concentration is equal to or higher than the above-mentioned lower limit, gas leakage from the bottled carbonated beverage can be suppressed.
In this specification, the "gas pressure" of a packaged beverage is calculated from the dissolved carbon dioxide concentration in the packaged beverage liquid at 20°C, and can be measured according to the method described in the examples of this specification.

[2] Here, it is preferable that the bottled carbonated beverage described in [1] above has a gas leakage prevention function.

[3] In the bottled carbonated beverage of [1] or [2] above, it is preferable that the concentration of dead bacteria of the beneficial bacteria is 1,000 billion/L or less. If the concentration of dead bacteria of the beneficial bacteria is below the upper limit, changes in the flavor of the beverage due to specific flavors derived from the beneficial bacteria can be suppressed.

[4] In any of the bottled carbonated beverages [1] to [3] above, it is preferable that the beneficial bacteria are one or more species selected from the group consisting of Lactobacillus and Lactococcus.

[5] In any of the bottled carbonated beverages [1] to [4] above, it is preferable that the beneficial bacteria are one or more species selected from the group consisting of Lactobacillus rhamnosus CRL1505, Lactococcus lactis subsp. lactis JCM5805, and Lactobacillus paracasei KW3110.

[6] In any of the packaged carbonated beverages described above in [1] to [5], the pH when containing carbon dioxide is preferably 1.0 or more and 5.5 or less. If the pH is within the above range, gas leakage from the packaged carbonated beverage can be further suppressed.
In this specification, the "pH when carbonated" of a packaged beverage means the pH under gas pressure, i.e., the pH when carbonated. The pH of a packaged beverage when carbonated can be measured according to the method described in the examples of this specification.

[7] It is preferable that any of the bottled carbonated beverages [1] to [6] above is a bottled carbonated beverage packed in a container with a content volume of 100 mL or more per bottle and 2100 mL or less per bottle.

[8] In any of the bottled carbonated beverages [1] to [7] above, it is preferable that the container is made of a plastic material.

[9] The present invention also provides a method for producing a bottled carbonated beverage, comprising: a blending step of blending killed beneficial bacteria to a killed bacteria concentration of 500 million cells/L or more; and a carbon dioxide gas addition step of adding carbon dioxide gas to the blend obtained in the blending step so that the gas pressure is 0.05 MPa or more and 0.5 MPa or less. This production method makes it possible to provide a bottled carbonated beverage in which gas leakage is suppressed.

[10] Furthermore, the present invention provides a method for preventing gas leakage from a bottled carbonated beverage, comprising: a blending step of blending killed beneficial bacteria to a killed bacteria concentration of 500 million cells/L or more; and a carbon dioxide gas addition step of adding carbon dioxide gas to the blend obtained in the blending step so that the gas pressure is 0.05 MPa or more and 0.5 MPa or less. This gas leakage prevention method makes it possible to provide a bottled carbonated beverage in which gas leakage has been prevented.

According to the present invention, it is possible to provide a bottled carbonated beverage in which gas leakage is suppressed.

(Packaged carbonated drinks)
The packaged carbonated beverage of the present invention is a beverage containing killed beneficial bacteria. More specifically, the packaged carbonated beverage of the present invention is characterized by a killed beneficial bacteria concentration of 500 million/L or more and a gas pressure of 0.05 MPa or more and 0.5 MPa or less. The beverage of the present invention also has a gas leakage prevention function, allowing the beverage to taste the stimulating sensation of carbon dioxide even when consumed a certain amount of time after opening. Furthermore, because the gas leakage prevention function is imparted by the addition of killed beneficial bacteria, it is also expected to exhibit beneficial effects derived from the beneficial bacteria, such as intestinal regulating effects and health promoting effects.

In the present invention, "packaged carbonated beverage" refers to a packaged beverage into which carbon dioxide (carbon dioxide) has been injected. For example, the carbonated beverage may be sweet or unsweetened. Sweetened carbonated beverages are not particularly limited, and examples include cider, ramune, cola, energy drinks, and fruit juice-containing carbonated beverages. Unsweetened carbonated beverages are not particularly limited, and examples include sparkling alcoholic beverages in which carbon dioxide has been injected into various non-sparkling alcoholic beverages, beer-flavored beverages, and carbonated water without sweeteners. Furthermore, the carbonated beverage is not limited to beverages into which carbon dioxide has been artificially injected, and may include natural carbonated water in which carbon dioxide has been dissolved in groundwater, or carbonated water in which carbon dioxide released by microorganisms during the fermentation process has been dissolved.

<Death of beneficial bacteria>
In the present invention, killed bacteria of useful bacteria are used. Examples of useful bacteria include, but are not limited to, bacteria of the genus Oenococcus, Bifidobacterium, Weissella, Tetragenococcus, Lactococcus, Leuconostoc, Pediococcus, Streptococcus, Enterococcus, Lactobacillus, acetic acid bacteria, and Bacillus.

Note that the Lactobacillus bacteria referred to in the present invention include bacteria that were classified as part of the Lactobacillus genus before the reclassification of the genus Lactobacillus. For example, with the reclassification of the genus Lactobacillus, the following genera have been newly added: Acetilactobacillus, Agrilactobacillus, Amylolactobacillus, Apilactobacillus, Bombilactobacillus, Companilactobacillus, Dellaglioa, Fructilactobacillus, Furfurilactobacillus, Holzapfelia, Lacticaseibacillus, Lactiplantibacillus, and Lapidilactobacillus. This includes bacteria classified into the genera Lapidilactobacillus, Latilactobacillus, Lentilactobacillus, Levilactobacillus, Ligilactobacillus, Limosilactobacillus, Liquorilactobacillus, Loigolactobacillus, Paralactobacillus, Paucilactobacillus, Schleiferilactobacillus, Secundilactobacillus, and the like.

Among the above, preferred bacteria are those of the genus Oenococcus, Bifidobacterium, Lentilactobacillus, Weissella, Tetragenococcus, Lactococcus, Leuconostoc, Pediococcus, Enterococcus, Lactobacillus, and Lactiplantibacillus. Furthermore, it is more preferred that the bacteria include one or more species selected from the group consisting of Lactobacillus and Lactococcus.

Examples of the Oenococcus genus include Oenococcus oeni. Specific examples of Oenococcus genus include Oenococcus oeni JCM6125.

Examples of the Bifidobacterium genus include Bifidobacterium animalis subsp. lactis and Bifidobacterium longum subsp. infantis. Specific examples of Bifidobacterium genus include Bifidobacterium animalis subsp. lactis JCM10602 and Bifidobacterium longum subsp. infantis JCM1222.

Examples of the Weissella genus include Weissella paramesenteroides and Weissella viridescens. Specific examples of Weissella genus include Weissella paramesenteroides JCM9890 and Weissella viridescens JCM1174.

Examples of the Tetragenococcus bacteria include Tetragenococcus halophilus. Specific examples of Tetragenococcus bacteria include Tetragenococcus halophilus NRIC0098.

Examples of the Lactococcus genus include Lactococcus lactis, Lactococcus lactis subsp. lactis, Lactococcus garvieae, Lactococcus lactis subsp. cremoris, Lactococcus lactis subsp. hordniae, and Lactococcus plantarum.

Specific examples of the above-mentioned Lactococcus genus bacteria include Lactococcus lactis subsp. lactis JCM5805, Lactococcus lactis subsp. lactis NBRC12007, Lactococcus lactis subsp. lactis NRIC1150, Lactococcus lactis subsp. lactis JCM20101, Lactococcus lactis subsp. lactis JCM7638, and Lactococcus lactis subsp. lactis ATCC11454, Lactococcus garvieae NBRC100934, Lactococcus lactis subsp. cremoris JCM16167, Lactococcus lactis subsp. cremoris NBRC100676, Lactococcus lactis subsp. holdoniae JCM1180, Lactococcus lactis subsp. holdoniae JCM11040, and Lactococcus plantarum JCM11056.

Examples of the Leuconostoc genus include Leuconostoc carnosum and Leuconostoc lactis. Specific examples of Leuconostoc genus include Leuconostoc carnosum JCM9695 and Leuconostoc lactis NBRC12455.

Examples of the Pediococcus genus include Pediococcus acidilactici, Pediococcus pentosaceus, Pediococcus cellicola, Pediococcus claussenii, Pediococcus damnosus, Pediococcus ethanolidurans, Pediococcus inopinatus, Pediococcus parvulus, and Pediococcus stilesii. Specific examples of the Pediococcus include Pediococcus acidilactici JCM8797, Pediococcus acidilactici K15, and Pediococcus damnosus JCM5886.

Examples of the Streptococcus genus include Streptococcus thermophilus. Specific examples of Pediococcus genus include Streptococcus thermophilus SBC8781.

Examples of the Enterococcus genus include Enterococcus alcedinis.

Examples of the Lactobacillus bacteria include Lactobacillus paracasei, Lactobacillus delbrueckii, Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus fructivorans, Lactobacillus hilgardii, Lactobacillus rhamnosus, Lactobacillus gasseri, Lactobacillus acidophilus, Lactobacillus bulgaricus, and Lactobacillus parakeefilii. parakefiri), Lactobacillus plantarum, and Lactobacillus pentosus.

Specific examples of Lactobacillus bacteria include Lactobacillus paracasei KW3110, Lactobacillus paracasei MCC1849, Lactobacillus paracasei K71, Lactobacillus rhamnosus GG, Lactobacillus rhamnosus CRL1505, Lactobacillus gasseri SBT2055, Lactobacillus acidophilus L-92, Lactobacillus bulgaricus OLL1073R-1, Lactobacillus parakeophili (newly classified as Lentilactobacillus parakeophili) JCM8573, Lactobacillus plantarum (newly classified as Lactipranclabacillus plantarum) L-137, and Lactobacillus pentosus (newly classified as Lactipranclabacillus pentosus) ONRICb0240.

The above-mentioned acetic acid bacteria are not particularly limited, but examples include bacteria of the genus Gluconacetobacter, Acetobacter, and Gluconobacter, preferably bacteria of the genus Gluconacetobacter, more preferably Gluconacetobacter hansenii, and even more preferably Gluconacetobacter hansenii GK-1.

The Bacillus bacteria are not particularly limited, but examples include Bacillus coagulans. Specific examples of Bacillus bacteria include Bacillus coagulans SANK70258.

Among the above, it is preferable that the useful bacteria include one or more species selected from the group consisting of Lactobacillus rhamnosus CRL1505, Lactococcus lactis subsp. lactis JCM5805, and Lactobacillus paracasei KW3110.

In the present invention, the killed useful bacteria are not particularly limited and may be dried or non-dried, but dried bacteria are preferred from the standpoint of storage stability of the killed useful bacteria. Of these, dried powder of killed useful bacteria is preferred.

The method for preparing killed useful bacteria is not particularly limited, and examples include a method in which the medium in which the bacteria have been cultured is sterilized and then the cells are collected by filtration and centrifugation, or a method in which the cells are collected from the medium in which the bacteria have been cultured by filtration and centrifugation, and then sterilized. Among useful bacteria, for example, lactic acid bacteria can be cultured using a culture medium for lactic acid bacteria known to those skilled in the art, such as MRS (de Man-Rogosa-Sharpe) medium, which contains glucose, protein hydrolysate, yeast extract, etc. Generally, the culture temperature is 30°C to 37°C, the culture period is 2 to 3 days, and the culture can be performed under anaerobic conditions.

Furthermore, the bacterial cells collected after cultivation can be further dried and crushed as necessary. There are no particular restrictions on the means of sterilization, and conventional methods for killing bacteria, such as heating, ultraviolet light, or gamma-ray irradiation, can be used.

The killed cell concentration of beneficial bacteria contained in the packaged carbonated beverage of the present invention must be 500 million cells/L or more, preferably 1 billion cells/L or more, more preferably 2 billion cells/L or more, even more preferably 5 billion cells/L or more, preferably 1,000 billion cells/L or less, more preferably 500 billion cells/L or less, even more preferably 100 billion cells/L or less, even more preferably 90 billion cells/L or less, even more preferably 80 billion cells/L or less, even more preferably 75 billion cells/L or less, even more preferably 50 billion cells/L or less, even more preferably 30 billion cells/L or less, and particularly preferably 20 billion cells/L or less. When the killed cell concentration of beneficial bacteria is above the above-mentioned lower limit, the gas leakage prevention function of the packaged carbonated beverage can be sufficiently enhanced. Furthermore, when the killed cell concentration of beneficial bacteria is below the above-mentioned upper limit, changes in the flavor of the beverage due to specific flavors derived from the beneficial bacteria can be suppressed.
The concentration of dead bacteria in a beverage can be controlled by adjusting the amount of dead bacteria added to the beverage. The concentration of dead bacteria in a beverage can be measured by any known method for measuring the number of bacteria, without particular limitation, including direct microscopy, particle electrochemical detection zone analysis, PCR, and flow cytometry, with flow cytometry being preferred.

<Gas pressure>
The gas pressure of the bottled carbonated beverage must be 0.05 MPa or more, preferably 0.1 MPa or more, and more preferably 0.2 MPa or more, and must be 0.5 MPa or less, preferably 0.4 MPa or less. If the gas pressure of the bottled carbonated beverage is within the above range, the gas leakage prevention function of the bottled carbonated beverage can be sufficiently enhanced.

In the packaged carbonated beverage of the present invention, the relationship between gas pressure and dead bacteria concentration of beneficial bacteria, where A is the value of [dead bacteria concentration of beneficial bacteria (100 million/L)/gas pressure (MPa)], is preferably 15 or more, more preferably 20 or more, even more preferably 100 or more, even more preferably 300 or more, and preferably 50,000 or less, more preferably 40,000 or less, and even more preferably 10,000 or less. If A is within the above range, the gas leakage prevention function of the packaged carbonated beverage can be further enhanced.

<Other ingredients>
The beverage of the present invention may contain one or more additives selected from the group consisting of acidulants, flavorings, colorants, sweeteners, preservatives, thickeners, stabilizers, emulsifiers, dietary fiber, bittering agents, antioxidants, pH adjusters, vitamins, nutritional fortifiers, umami components, dietary fiber, extracts, solvents, minerals, water-soluble functional components, and fat-soluble functional components, to the extent that the effects of the present invention are not impaired. The additives are not particularly limited and commonly used ones can be used, but specific examples include acesulfame K, stevia, and sucralose as sweeteners, citric acid as acidulants, soybean polysaccharides and pectin as stabilizers, and sodium, potassium, magnesium, and calcium as minerals.

Among the above-listed ingredients, it is preferable that the packaged carbonated beverage contains citric acid. The concentration of citric acid is not particularly limited as long as it can suitably adjust the pH of the packaged carbonated beverage to the range below, but for example, it is preferably 0.0001% by mass or more, more preferably 0.001% by mass or more, even more preferably 0.005% by mass or more, preferably 1% by mass or less, more preferably 0.5% by mass or less, even more preferably 0.1% by mass or less, even more preferably 0.05% by mass or less, and particularly preferably 0.01% by mass or less. If the citric acid concentration is within the above range, the gas leakage prevention function of the packaged carbonated beverage can be further enhanced.

<pH of bottled carbonated beverage containing carbon dioxide>
The pH of a packaged carbonated beverage when it contains carbon dioxide refers to the pH under gas pressure, i.e., the pH in a carbonated state. The pH under gas pressure of a packaged beverage when it contains carbon dioxide is preferably 1.0 or higher, more preferably 1.5 or higher, even more preferably 2.0 or higher, particularly preferably 2.5 or higher, preferably 5.5 or lower, more preferably 5.0 or lower, and even more preferably 4.5 or lower. If the pH under gas pressure of the packaged beverage is above the above lower limit, gas leakage from the packaged carbonated beverage can be further suppressed and excessive sourness can be suppressed. If the pH under gas pressure of the packaged beverage is below the above upper limit, the harsh taste of the packaged carbonated beverage can be suppressed.

<Container>
Examples of containers for the packaged beverage of the present invention include containers made of plastic materials (plastic bottle containers) such as PET bottles, polypropylene bottles, and polyvinyl chloride bottles, as well as bottle containers and can containers. The capacity of the container is not particularly limited, but may be, for example, 100 mL or more, preferably 350 mL or more, for example, 2100 mL or less, preferably 1600 mL or less. More specifically, the capacity of containers made of plastic materials is preferably 150 mL or more, more preferably 310 mL or more, even more preferably 360 mL or more, particularly preferably 400 mL or more, preferably 1300 mL or less, more preferably 1200 mL or less, even more preferably 950 mL or less, and particularly preferably 700 mL or less. Furthermore, the capacity of bottle containers is preferably 150 mL or more, more preferably 430 mL or more, and preferably 1300 mL or less. The capacity of the can container is preferably 150 mL or more, more preferably 260 mL or more, and is preferably 1250 mL or less, more preferably 900 mL or less, even more preferably 700 mL or less, and particularly preferably 400 mL or less.

(Production method of bottled carbonated beverage)
The method for producing a packaged carbonated beverage of the present invention is characterized by comprising a blending step of blending killed beneficial bacteria to a killed bacteria concentration of 500 million/L or more, and a carbon dioxide gas addition step of adding carbon dioxide gas to the blend obtained in the blending step so that the gas pressure is 0.05 MPa or more and 0.5 MPa or less. The method for producing a packaged carbonated beverage of the present invention is not particularly limited as long as it includes the above-mentioned specific blending step and carbon dioxide gas addition step. In other words, the bottled carbonated beverage can be produced according to a conventionally known method for producing a beverage as long as it includes the above-mentioned blending step and carbon dioxide gas addition step.

Examples of a blending process for blending killed beneficial bacteria to a concentration of 500 million/L or more include a process of adding an optional solvent such as water, and other optional ingredients, to a mixing tank, and then adding the killed beneficial bacteria to the mixture at a rate of 500 million/L or more. Alternatively, examples include a process of simultaneously adding the killed beneficial bacteria and an optional solvent to the mixing tank. Of course, the manner of addition and the order of blending are not limited to the above.

The carbon dioxide gas addition process, in which carbon dioxide gas is added to the compound obtained in the compounding process so that the gas pressure is 0.05 MPa or more and 0.5 MPa or less, can be carried out by using a carbonator to place the compound obtained above and inject and dissolve carbon dioxide gas to achieve the specified gas pressure.

The carbonated beverage obtained through the carbon dioxide gas addition process can then be filled into a container such as those listed above and sealed in accordance with known methods to produce the bottled carbonated beverage of the present invention.

(Method for preventing gas leakage from bottled carbonated beverages)
The method for preventing gas leakage from bottled carbonated beverages of the present invention is not particularly limited, as long as it includes a blending step of blending dead cells of beneficial bacteria to a dead cell concentration of 500 million cells/L or more, and a carbon dioxide gas addition step of adding carbon dioxide gas to the blend obtained in the blending step so that the gas pressure is 0.05 MPa or more and 0.5 MPa or less.

The blending process and carbon dioxide gas addition process can be similar to those described in relation to the method for producing the bottled carbonated beverage of the present invention.

The present invention will be specifically described below based on exemplary tests, but the present invention is not limited to the following descriptions.
The samples from each test plot described below were subjected to various measurements and evaluations using the following methods.

(Physical property measurement)
<Gas pressure loss rate measurement method>
The gas pressure loss rate of the carbonated beverage samples in each test group was determined using a packaged beverage analyzer PBA (equipped with a filling device PFD, a carbonate concentration meter CarboQC ME, a pH meter MEASURING MODULE pH3201, and a density meter DMA4501) (manufactured by Anton Paar) by the following method.
First, the temperature of the carbonated beverage sample in the container before opening was brought to 20°C, and then the sample was left to stand for 72 hours or more to stabilize the gas-liquid equilibrium within the sample. The left-standing sample was thoroughly stirred up and down and then analyzed using a measuring device to obtain the gas pressure value before opening. Meanwhile, another left-standing sample was gently opened, left to stand at room temperature for 1 hour, then closed, and similarly thoroughly stirred up and down to stabilize the gas-liquid equilibrium. After that, the sample was analyzed using a measuring device to obtain the gas pressure value 1 hour after opening. The gas pressure loss rate of the carbonated beverage sample was calculated from the gas pressure values before and 1 hour after opening using the following formula.
Gas pressure loss rate = (gas pressure value before opening - gas pressure value 1 hour after opening) x 100 ÷ gas pressure value before opening

<pH under gas pressure>
The pH under gas pressure was measured using the Packaged Beverage Analyzer PBA described above.

(Test 1) Effect of pH under gas pressure on gas pressure loss rate The following test was conducted to investigate the relationship between pH under gas pressure and gas pressure loss rate in carbonated beverages.

<Sample preparation>
Water was placed in a 500 mL plastic container, and phosphoric acid or sodium hydroxide was added to achieve the pH under the gas pressure shown in Table 1.The solution was then carbonated (dissolved by injecting carbon dioxide gas) using a carbonator at a liquid temperature of 20°C so that the gas pressure before opening was 0.35 MPa, producing carbonated beverage samples for test areas 1-4.

<Measurement>
For the carbonated beverage samples obtained in the above test groups, the pH under gas pressure and the gas pressure loss rate one hour after opening were determined according to the above-mentioned methods for measuring pH under gas pressure and measuring gas pressure loss rate. Six samples were prepared for each test group, and measurements were taken of three samples each before and one hour after opening, and the gas pressure loss rate was calculated from the average of the three samples. The results are shown in Table 1.

(Test 2) Effect of dead concentration of beneficial bacteria on gas pressure loss rate The following test was conducted to investigate the relationship between the dead concentration of beneficial bacteria and the gas pressure loss rate in carbonated drinks.

<Sample preparation>
Water was placed in a 500 mL plastic container, and 0.005% citric acid was added to adjust the pH to 3.5 under gas pressure. Matcha powder (Aiya Co., Ltd.), killed yeast powder (Oriental Yeast Co., Ltd.), or killed rhamnosus bacteria (including one or more species of Lactobacillus rhamnosus) was added to achieve the final concentrations listed in Table 2. This sample was carbonated using a carbonator at a liquid temperature of 20°C so that the gas pressure before opening was 0.24 MPa, producing carbonated beverage samples for test plots 5-11.
The killed rhamnosus bacteria used were prepared by diluting 350 billion/g live rhamnosus bacteria powder (containing one or more species of Lactobacillus rhamnosus) with water 35 times and sterilizing it at 80°C for 60 minutes to prepare an aqueous solution of 10 billion/g killed rhamnosus bacteria.

<Measurement>
For the carbonated beverage samples obtained in the above test groups, the pH under gas pressure and the gas pressure loss rate one hour after opening were determined according to the above-mentioned methods for measuring pH under gas pressure and measuring gas pressure loss rate. Six samples were prepared for each test group, and measurements were taken of three samples each before and one hour after opening, and the gas pressure loss rate was calculated from the average of the three samples. The results are shown in Table 2.

(Test 3) The effect of the concentration of dead beneficial bacteria on the gas pressure loss rate and the relationship with the gas pressure before opening The following test was conducted to investigate the effect of the concentration of dead beneficial bacteria on the gas pressure loss rate and the relationship with the gas pressure before opening.

<Sample preparation>
Water was placed in a 500 mL plastic container and killed Rhamnosus bacteria was added to achieve the final concentration shown in Table 3. This sample was carbonated using a carbonator at a liquid temperature of 20°C so that the gas pressure before opening was 0.38 MPa, producing carbonated beverage samples for test plots 12 and 13.
The killed rhamnosus bacteria used were prepared by diluting 350 billion/g live rhamnosus bacteria powder (containing one or more species of Lactobacillus rhamnosus) with water 35 times and sterilizing it at 80°C for 60 minutes to prepare an aqueous solution of 10 billion/g killed rhamnosus bacteria.

<Measurement>
For the carbonated beverage samples obtained in the above test groups, the pH under gas pressure and the gas pressure loss rate one hour after opening were measured according to the above-mentioned methods for measuring pH under gas pressure and measuring gas pressure loss rate. Six samples were prepared for each carbonated beverage sample in the above test groups, and measurements were taken before opening and one hour after opening (three samples each), and the pH under gas pressure and the gas pressure loss rate were calculated from the average of the three samples. The results are shown in Table 3.

(Test 4) Effect of Killed Beneficial Bacteria on Gas Pressure Loss Rate in Packaged Carbonated Drinks Containing Resistant Dextrin The following test was conducted to investigate the effect of killed beneficial bacteria on gas pressure loss rate in packaged carbonated drinks containing resistant dextrin.

<Sample preparation>
Water was placed in a 500 mL plastic container, to which 1.1% indigestible dextrin was added, and 0.005% citric acid was added to adjust the pH to 3.5 under gas pressure, and killed Rhamnosus bacteria were added to achieve the final concentration shown in Table 4. This sample was carbonated using a carbonator at a liquid temperature of 20°C so that the gas pressure before opening was 0.30 MPa, to produce carbonated beverage samples for test plots 14 and 15.
The killed rhamnosus bacteria used were prepared by diluting 350 billion/g live rhamnosus bacteria powder (containing one or more species of Lactobacillus rhamnosus) with water 35 times and sterilizing it at 80°C for 60 minutes to prepare an aqueous solution of 10 billion/g killed rhamnosus bacteria.

<Measurement>
For the carbonated beverage samples obtained in the above test groups, the pH under gas pressure and the gas pressure loss rate one hour after opening were measured according to the above-mentioned methods for measuring pH under gas pressure and measuring gas pressure loss rate. Six samples were prepared for each test group, and measurements were taken of three samples each before and one hour after opening, and the gas pressure loss rate was calculated from the average of the three samples. The results are shown in Table 4.

From Table 1, it can be inferred that for carbonated beverages with a pre-opening gas pressure of 0.05 MPa or more and 0.5 MPa or less, the effect of suppressing the gas pressure loss rate of the beverage after opening increases as the pH under gas pressure increases when the pH under gas pressure is between 1.4 and 1.7. Table 1 also shows that a generally high effect of suppressing gas pressure loss is obtained when the pH under gas pressure is in the range from around 1.7 to 5.0.
Table 2 shows that test plots 8-11, which were carbonated beverage samples containing 500 million or more killed beneficial bacteria per liter and with a pre-opening gas pressure of 0.05 MPa to 0.5 MPa, suppressed the gas pressure loss rate after opening. Furthermore, comparing test plots 8-11 with test plots 6 and 7, which used matcha powder or killed yeast as an additive, shows that the suppression of the gas pressure loss rate is a specific effect when killed beneficial bacteria are added.
Table 3 shows that in test area 13, a carbonated beverage sample containing more than 500 million dead beneficial bacteria per liter and with a pre-opening gas pressure of 0.05 MPa or more and 0.5 MPa or less, the gas pressure loss rate after opening was suppressed even at a pre-opening gas pressure higher than in test area 2.
Table 4 shows that even when the carbonated beverage contained indigestible dextrin, the gas pressure loss rate after opening was suppressed in test group 15, which was a carbonated beverage sample containing 10 billion dead beneficial bacteria/L and having a gas pressure before opening of 0.05 MPa or more and 0.5 MPa or less.

According to the present invention, it is possible to provide a bottled carbonated beverage in which gas leakage is suppressed.

Claims (8)

It is a packaged carbonated beverage,
Contains dead beneficial bacteria,
The useful bacterium is a bacterium of the genus Lactobacillus rhamnosus,
The concentration of dead bacteria of the beneficial bacteria is 500 million/L or more, and
The gas pressure at 20°C is 0.05 MPa or more and 0.5 MPa or less,
The pH when containing carbon dioxide is 1.0 or more and 5.5 or less,
When the value of [killed bacteria concentration of the useful bacteria (billion bacteria/L)/gas pressure (MPa)] is A, A is 15 or more and 50,000 or less.
Packaged carbonated drinks. The bottled carbonated beverage according to claim 1, which has a gas leakage prevention function. The bottled carbonated beverage according to claim 1, wherein the concentration of dead beneficial bacteria is 1,000 billion/L or less. The bottled carbonated beverage according to claim 1, wherein the beneficial bacterium is Lactobacillus rhamnosus CRL1505. The bottled carbonated beverage according to claim 1, packed in a container with a capacity of 100 mL or more per bottle and 2100 mL or less per bottle. The bottled carbonated beverage according to any one of claims 1 to 5, wherein the container is made of a plastic material. A method for producing a bottled carbonated beverage,
A blending step of blending killed bacteria of the genus Lactobacillus rhamnosus as useful bacteria to a killed bacteria concentration of 500 million cells/L or more;
a pH adjustment step of adjusting the pH so that the pH when containing carbon dioxide is 1.0 or more and 5.5 or less;
a carbon dioxide gas adding step of adding carbon dioxide gas to the blend obtained in the blending step so that the gas pressure at 20°C is 0.05 MPa or more and 0.5 MPa or less, and where A is the value of [killed bacteria concentration of the useful bacteria (100 million bacteria/L)/gas pressure (MPa)], A is 15 or more and 50,000 or less ;
A method for producing a bottled carbonated beverage, comprising: A method for preventing gas leakage from a bottled carbonated beverage,
A blending step of blending killed bacteria of the genus Lactobacillus rhamnosus as useful bacteria to a killed bacteria concentration of 500 million cells/L or more;
a pH adjustment step of adjusting the pH so that the pH when containing carbon dioxide is 1.0 or more and 5.5 or less;
a carbon dioxide gas adding step of adding carbon dioxide gas to the blend obtained in the blending step so that the gas pressure at 20°C is 0.05 MPa or more and 0.5 MPa or less;
A method for preventing gas leakage from a bottled carbonated beverage, comprising: