JP2011103785A - Container-packed, low-acid beverage and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a container-packed, low-acid beverage which is prevented from deformation and/or defective sealing caused on a package during storage of a hot warmer due to carbon dioxide derived from baking soda added in order to adjust pH of the container-packed, low-acid beverage, and reduction in accuracy of striking check in a production process. <P>SOLUTION: The container-packed, low-acid beverage is such that the pH of a beverage is adjusted with baking soda, and the concentration of the carbon dioxide per unit volume of a head space when caught in saturated salt water having pH of ≤4 accounts for ≤10% when stored at 25°C and ≤20% when stored at 75°C. The method for producing the container-packed, low-acid beverage includes adding baking soda to a low-acid beverage at high concentration and high temperature, stirring the mixture to eliminate carbon dioxide from the baking soda followed by diluting the beverage to prepare the beverage, charging the beverage in a package and hermetically sealing the package. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to low acid beverages such as coffee beverages and tea beverages that are sold by being filled and sealed in containers such as plastic bottles, plastic cups, and metal cans, and a method for producing the same. The present invention also relates to a container-packed low-acid beverage that does not cause container deformation or poor sealing and a method for producing the same.

  In the case of a low acid beverage such as a coffee beverage or a tea beverage, a high concentration extract is generally used at the time of preparation. The high-concentration extract (extract) may have a low pH due to its own pH, such as a coffee extract, or may be lowered by ascorbic acid added as an antioxidant, such as an extract of a tea beverage. And since the sourness becomes strong when the pH of the final product is low, it is necessary to adjust the pH at any stage of the preparation of the final product. In addition, in milk coffee drinks and milk tea mixed with milk components, when the pH at the time of preparation is low or too high, the beverage contents such as milk components tend to coagulate and precipitate or become gel. Therefore, conventionally, when producing low acid beverages such as coffee beverages and tea beverages, the pH is adjusted to prepare the beverage content. As a pH adjuster, the adjustment is easy and the content deteriorates. Since it is possible to suppress a decrease in pH associated with sodium bicarbonate, sodium bicarbonate (sodium bicarbonate) having a buffering effect has been frequently used.

  And recently, PET bottled beverages and cupped beverages have been warmed and sold, and container-packed low-acid beverages have also been warmed and sold in hot warmers. In this case, while being stored in hot warmers, The problem is that PET bottles and cups are deformed and cause poor sealing. As a result of the study, the present inventors have studied that such container deformation and poor sealing are used at the time of filling and sealing in order to replace carbon dioxide (carbon dioxide) derived from baking soda added during preparation and air in the headspace of the container. It was found that the expansion by carbon dioxide gas derived from the substitution gas consisting of a mixed gas of nitrogen and carbon dioxide is influential. That is, the carbon dioxide gas derived from baking soda and the carbon dioxide gas derived from the mixed gas for head space replacement are mostly dissolved in the beverage content in the form of gas or ions at room temperature, but at 60 ° C. with a hot warmer. As described above, for example, when heated to about 75 ° C., carbon dioxide gas and water vapor are generated from the beverage in addition to the expansion of the head space, and come out into the head space to expand the container. At this time, since the expansion of the carbon dioxide gas derived from the baking soda is larger than the expansion of the carbon dioxide gas derived from the mixed gas in the head space replacement, the container is deformed and the sealing is poor. It should be noted that the temperature of the beverage as the contents may be 75 ° C. or higher when in the rapid heating mode with a hot warmer.

  On the other hand, in the manufacturing process of metal canned low acid beverages such as canned coffee beverages, even when defective cans are detected by punching, the internal pressure of the can changes due to the generation of carbon dioxide derived from baking soda, and the amount of carbon dioxide remaining In many cases, there is a problem that the container is deformed at the time of retort sterilization or the accuracy of punching is lowered.

  Patent Document 1 describes alkali ions having a pH of 8.0 or more obtained through an anion exchange resin in order to reduce the salty taste based on the addition of baking soda during the pH adjustment of coffee beverages and tea beverages and to improve the flavor of the product. A method of reducing the amount of sodium bicarbonate added by extracting coffee or tea with water is disclosed.

  However, according to this method, special equipment is required to obtain alkaline ionized water, and it cannot be applied as it is to an existing container-packed low-acid beverage production apparatus. I need.

  Patent Document 2 discloses a milk component-free solution, milk, and the like in order to prevent agglomeration, precipitation, turbidity and the like without causing flavor and quality deterioration due to addition of baking soda in coffee beverages and tea beverages containing milk components. It discloses that dissolved gas is removed by bubbling nitrogen in any one adjustment step of the component-containing liquid and the milk component mixed solution.

  However, according to this method, although the deterioration of flavor can be prevented by reducing the amount of sodium bicarbonate added by nitrogen bubbling, a new problem arises in that the flavor of the beverage is impaired by nitrogen bubbling itself. .

JP 7-184547 A JP 2002-282903 A

  The present invention has been considered in view of the above problems in the conventional method for producing a packaged low-acid beverage, and the object of the present invention is to achieve an appropriate pH in terms of taste when preparing a packaged low-acid beverage. At the same time, while preventing the coagulation precipitation or gelation of the beverage contents due to the addition of milk components, etc., carbon dioxide derived from baking soda added for pH adjustment and nitrogen for replacing the air in the container headspace・ Contains problems such as container deformation and poor sealing caused by carbon dioxide gas derived from carbon dioxide mixed gas during storage of hot warmers, as well as a decrease in accuracy of inspection in the manufacturing process, without significant changes to existing manufacturing equipment, and by nitrogen bubbling. An object of the present invention is to provide a container-packed low-acid beverage that can be easily solved without impairing the flavor and flavor of the beverage and a method for producing the same.

  As a result of repeating various experiments and researches to achieve the above object, the present inventors have achieved an appropriate pH in terms of the taste of a low acid beverage, and at the same time, the content of the beverage by adding milk components etc. Baking soda is added to adjust the pH necessary to prevent coagulation precipitation or gelation. At the time of beverage preparation, baking soda is added to a highly acidic, low-acid beverage in a high temperature state, stirred and mixed with the sodium bicarbonate. After removing the carbon dioxide gas by foaming, if the beverage is diluted to prepare the milk component, etc., the beverage after completion of this preparation step is filled and sealed in a container, and the carbon dioxide gas derived from sodium bicarbonate during storage in the hot warmer Generation and expansion can be remarkably suppressed, and even if there is expansion of carbon dioxide gas derived from the headspace replacement gas, container deformation and sealing failure can be sufficiently prevented, and the accuracy of punching is reduced in the manufacturing process. The It found that no Rukoto, have reached the present invention.

  That is, the first configuration of the present invention that achieves the above object is a carbon dioxide gas per unit volume of the headspace when collected in a saturated saline solution having a pH of 4 or less in a container-filled low-acid beverage adjusted in pH with sodium bicarbonate. A container-packed low-acid beverage characterized by a concentration of 10% or less when stored at 25 ° C. and 20% or less when stored at 75 ° C.

  In addition to the first configuration, the second configuration of the present invention is a container-packed low-acid beverage in which the total carbonic acid content in the container after filling and sealing is 45% or less with respect to the total carbonic acid amount obtained from the added amount of baking soda It is.

  A third configuration of the present invention is a container-packed low-acid beverage in which the head space is replaced with a mixed gas of nitrogen gas and carbon dioxide during filling in addition to the first or second configuration.

  The fourth configuration of the present invention is a container-packed low acid beverage in which the low acid beverage is a coffee beverage or a tea beverage in addition to any of the first to third configurations.

  A fifth configuration of the present invention is a container-packed low-acid beverage in which the container is a plastic bottle, a plastic cup, or a metal can in addition to any of the first to fourth configurations.

  According to a sixth aspect of the present invention, in the method for producing a container-packed low-acid beverage whose pH is adjusted with sodium bicarbonate, sodium bicarbonate is added to and stirred in a high-concentration, high-temperature, low-acid beverage to remove carbon dioxide from the sodium bicarbonate. Then, it is a manufacturing method of the container-packed low-acid drink characterized by diluting and preparing a drink and filling and sealing a container.

  The 7th structure of this invention is a manufacturing method of the container-packed low-acid drink in which the density | concentration of the said low-acid drink is 2 times or more of the density | concentration after dilution, and pH is 6 or less in addition to a 6th structure.

  The 8th structure of this invention is a manufacturing method of the container stuffing low acid drink whose temperature of the said low acid drink is 50 degreeC or more in addition to the 6th or 7th structure.

  In the ninth configuration of the present invention, in addition to any of the sixth to eighth configurations, the amount of carbonate derived from baking soda after filling and sealing is 45% or less with respect to the total amount of carbonate determined from the amount of sodium bicarbonate added. It is a manufacturing method of a container-packed low-acid drink.

  A tenth configuration of the present invention is a method for producing a container-filled low-acid beverage in which the headspace is replaced with a mixed gas of nitrogen gas and carbon dioxide gas at the time of filling, in addition to any of the sixth to ninth configurations.

  The 11th structure of this invention is a manufacturing method of the container stuffing low acid drink whose low acid drink is a coffee drink or a tea drink in addition to the 6th-10th structure.

  The twelfth configuration of the present invention is a method for producing a container-filled low-acid beverage in which the container is a plastic bottle, a plastic cup or a metal can in addition to any of the sixth to eleventh configurations.

  According to the container-packed low-acid beverage of the present invention, the amount of carbon dioxide derived from baking soda is remarkably reduced during the preparation of the beverage, so the mixed gas is derived by substituting a mixed gas of nitrogen gas and carbon dioxide in the headspace. Even if the amount of carbon dioxide is present, the total amount of carbon dioxide contained in the beverage is remarkably reduced. Even if the container is stored for a long period of time with a hot warmer for warm sales, the generation of carbon dioxide and Providing a product with high punching accuracy that does not cause container deformation or sealing failure due to expansion, and can prevent a decrease in punching accuracy during the manufacturing process due to expansion of the can when the container is a metal can. Can do.

  In addition, according to the method for producing a containerized low-acid beverage of the present invention, sodium bicarbonate is added to a low-acid beverage in a high concentration, high-temperature state, and the beverage is diluted by diluting the beverage after removing carbon dioxide from the sodium bicarbonate. Per unit volume in the headspace by simply removing the carbon dioxide derived from baking soda using existing low-acid beverage production equipment without using special equipment during compounding. The carbon dioxide concentration of can be greatly reduced.

2 is a photograph illustrating the state of foam generation before and after the addition of a sodium bicarbonate solution in Experimental Example 1. It is explanatory drawing which illustrates the relationship between the temperature of a high concentration coffee liquid, and a dissolved carbon dioxide gas concentration. It is explanatory drawing which illustrates the relationship between the stirring speed of high concentration coffee liquid, and dissolved carbon dioxide gas concentration. It is explanatory drawing which illustrates the relationship between the elapsed time after adding a sodium bicarbonate solution to high concentration coffee liquid, and a dissolved carbon dioxide gas concentration. It is explanatory drawing which illustrates the relationship between the elapsed time after adding the baking soda solution in the case of changing the extract density | concentration of a high concentration coffee liquid, and dissolved carbon dioxide gas density | concentration. It is explanatory drawing which illustrates the state before and behind the heating of the plastic cup filling low-acid drink used in the Example.

  In the present invention, when a plastic bottle such as a PET bottle or a plastic cup such as a polypropylene cup is filled and sealed with a baking soda and heated with a hot warmer, the container is deformed or poorly sealed due to carbon dioxide derived from the baking soda. It can be applied to containers that are prone to occur. The present invention can also be applied to metal cans in order to improve the accuracy of punching of metal cans that are filled and sealed with contents to which sodium bicarbonate is added.

  Beverages to which the present invention is applied are low-acid beverages that require the addition of baking soda for pH adjustment, and coffee beverages and tea beverages are typical, but are not limited thereto.

  As a result of the experiment, the concentration of carbon dioxide gas per unit volume of the head space when collected in a saturated saline solution having a pH of 4 or less was 10% or less when stored at 25 ° C. If it is 20% or less when stored at 75 ° C., the expansion of the carbon dioxide gas in the head space will not cause the plastic container to be deformed or cause a sealing failure. It has been found that there is no possibility of causing a problem, and in the case where the container is a metal can, there is no possibility of causing a decrease in percussion accuracy due to the expansion of carbon dioxide in the head space.

  In order to keep the carbon dioxide concentration per unit volume of the head space within the above range, the total amount of carbon dioxide in the container after filling and sealing must be 45% or less with respect to the total amount of carbon dioxide obtained from the amount of sodium bicarbonate added. is there. The total amount of carbonic acid in the container after filling and sealing (carbonic acid derived from baking soda and headspace replacement gas) is confirmed by the following method from the amount dissolved in the beverage and the amount present in the headspace. can do.

Dissolved carbon dioxide in beverages exists in a single molecule (CO ₂ ) state, a bicarbonate ion (HCO ₃ ⁻ ), and a carbonate ion (CO ₃ ²⁻ ) state, and each is in an ionization equilibrium state in a steady state. it is conceivable that. Each abundance is considered to vary depending on the pH of the beverage. When the pH is 4 or less, most of them exist in a single molecule (CO ₂ ) state, and as the pH increases, bicarbonate ions (HCO ₃ ⁻ ) are present. When the pH increases and exceeds 8, single molecules (CO ₂ ) hardly exist, and carbonate ions (CO ₃ ²⁻ ) begin to exist in addition to hydrogen carbonate ions (HCO ₃ ⁻ ). The total carbonic acid concentration and single molecule (CO ₂ ) concentration in beverages are measured by carbon dioxide concentration meter (Ti-9004) and TCD (thermal conductivity) sensor manufactured by Toko Chemical Laboratories as in the experimental examples described later. A dissolved carbon dioxide concentration meter (model 3658) manufactured by Hack Ultra Co., Ltd. using the method can be used. The total carbonic acid concentration (Call) can be measured by setting the pH of the beverage to 4 or less. A value measured without adjusting the pH can be evaluated as a single molecule (CO ₂ ), that is, a dissolved concentration (Cgas) in a carbon dioxide state. As a result, the concentration dissolved as ions (Cion) is Cion = Call-Cgas.
As the total amount of the bicarbonate ion (HCO ₃ ⁻ ) concentration and the carbonate ion (CO ₃ ²⁻ ) concentration. From these values and the filling amount of the beverage, the total amount of carbonic acid, the amount of carbon dioxide (CO ₂ ), and the amount of ions in the beverage can be determined.

Next, the amount of carbon dioxide gas in the headspace (Vco2) is obtained by collecting the headspace gas in a saturated saline solution having a pH of 4 or less at room temperature, and using gas chromatography or a known carbon dioxide concentration measuring device for the collected gas. Product of carbon dioxide concentration (Hco2) measured and the amount of collected gas (Vall) Vco2 = Vall × Hco2
Can be obtained from

The total amount of carbonic acid (the amount of carbonic acid derived from baking soda and the head space replacement gas) in the container after filling and sealing is obtained as the sum of Call and Vco2. The amount of carbon dioxide contained in the theoretical baking soda (sodium bicarbonate NaHCO ₃ ) is 52.4% by weight of the added amount of baking soda, so 52.4% by weight of the added amount of baking soda per container and one container The residual rate with respect to the amount of carbonic acid derived from baking soda can be evaluated from the total amount of carbonic acid.

The carbon dioxide gas in the head space and the dissolved carbon dioxide gas (single molecule (CO ₂ )) in the beverage are in a solution equilibrium state, and further the dissolved carbon dioxide gas (single molecule (CO ₂ )) and hydrogen carbonate ion (HCO _3). ^- ) And carbonate ions (CO ₃ ²⁻ ) are in an ionization equilibrium state. Moreover, since the pH of coffee beverages and tea beverages is in the range of about 6 to 7, if the total amount of carbonate after filling and sealing can be reduced to 45% or less with respect to the total amount of carbonate determined from the amount of sodium bicarbonate added. The expansion in the hot warmer can be reduced, and the container deformation and the sealing failure can be prevented. Furthermore, since the carbon dioxide and dissolved carbon dioxide in the head space are in a dissolution equilibrium, when the head space is stored at 25 ° C. at 10% or less and at 75 ° C. is stored at 20% or less, container deformation or Sealing failure can be prevented.

  If the carbon dioxide concentration per unit volume of the head space can be kept within the above range, the air in the head space of the container is replaced with a mixed gas of nitrogen gas and carbon dioxide when filling the container of the low acid beverage. There is no problem.

Next, a method for producing a container-packed low-acid beverage whose pH has been adjusted with the baking soda will be described.
The characteristics of the method for producing a container-packed low-acid beverage according to the present invention are as follows. After removing carbon dioxide from baking soda, the beverage is diluted and mixed, and the container is filled and sealed.

  The pH of low-acid beverages such as coffee beverages and tea beverages before adding sodium bicarbonate is usually 6 or less. And in order to efficiently produce a low-acid beverage that achieves the object of the present invention, the concentration of the low-acid beverage before adding baking soda is the final concentration, that is, the concentration at which the final preparation step is performed after dilution. It is necessary to have a high concentration. By adding baking soda to highly concentrated low-acid beverages, it becomes possible to efficiently disperse the baking soda solution in the low-acid beverages in a short time, and carbon dioxide gas ionizes and foams in a gaseous form without remaining. Can be removed. The concentration of the low-acid beverage before adding sodium bicarbonate is preferably at least twice the concentration after dilution, more preferably at least 2.5 times.

  Moreover, the low-acid drink at the time of adding sodium bicarbonate needs to be in a high temperature state. When the beverage is in a high temperature state, the reaction between the high-concentration low-acid beverage and baking soda is remarkably enhanced, and the pH adjustment of the beverage and the foaming and removal of carbon dioxide gas are promoted. For this reason, the temperature of the low acid beverage when adding baking soda is preferably 50 ° C. or higher, more preferably 60 ° C. or higher, and most preferably 70 ° C. or higher.

  In order to efficiently adjust the pH of the beverage and foam and remove carbon dioxide, it is preferable to add sodium bicarbonate in a short time while stirring the low-acid beverage at high speed. Stirring speed and addition time of baking soda vary depending on the capacity of the low-acid beverage blending tank and the stirring means, so it cannot be determined in general, but under the given conditions, the beverage is stirred as fast as possible and the baking soda is drinked in the shortest possible time. It is desirable to add to.

In this way, by adding baking soda to the high-concentration, high-temperature, low-acid beverage, stirring is continued for a while, so that carbon dioxide gas from the baking soda is foamed and removed from the low-acid beverage. When the carbon dioxide is sufficiently removed from the beverage, the stirring is terminated, and pure water is added to the low-acid beverage to dilute to the final concentration, and after cooling, the final blending step is performed. In the blending process, additives such as milk components (whole milk powder, skimmed milk powder, etc.), sugar, emulsifiers, flavors and the like are added to complete the blending of the low acid beverage. The low-acid beverage after completion of preparation is sent to a filling device, filled in a container such as a plastic bottle, plastic cup, or metal can by a conventional method, and sealed to obtain a product.

Experimental example

A table test was conducted to confirm the characteristics of carbonic acid derived from baking soda.
[Method for measuring carbon dioxide concentration in sample solution]
For measuring the carbonic acid concentration in the sample solution, a carbon dioxide concentration measuring device (Ti-9004) manufactured by Toko Chemical Laboratory was used. Carbonic acid is dissolved in a gas state and an ion state, and a value (correction value = actual value / 1.1) measured without adjusting pH is a dissolved concentration (Cgas), pH in the carbon dioxide state. Was adjusted to 4 or less, and the measured value was evaluated as the total carbonic acid concentration (Call). As a result, the concentration dissolved as ions (Cion) is Cion = Call-Cgas.
As required. All concentrations were evaluated in terms of CO2. Further, when the concentration of the sample liquid exceeded the proper use concentration range (2 to 440 mg / L) of the present apparatus, the sample liquid was diluted and measured, and the measured value was corrected by the dilution factor. When the temperature was high, the sample solution was sealed so that the carbon dioxide gas would not escape, and then quenched with ice water and brought to room temperature.

(1) Confirmation with sodium bicarbonate solution Sodium bicarbonate is generally added in the form of an aqueous solution. Therefore, since it seems to be effective in reducing carbon dioxide gas derived from baking soda, sodium bicarbonate was dissolved in hot water as follows, and the change over time in the total dissolved carbonic acid concentration was evaluated.

  900 g of heated ion-exchanged water was put into a 2 liter flask, and 100 g of sodium bicarbonate was added while stirring to prepare a 10 wt% sodium bicarbonate solution. The time-dependent change in the amount of dissolved carbon dioxide in the solution was evaluated from 1 minute to 30 minutes after the addition. The baking soda solution was kept warm with a hot stirrer and a heat insulating material, and the rotation speed of the stirrer was 200 rpm. The temperature of ion-exchanged water immediately before adding sodium bicarbonate was 85 ° C, 77 ° C immediately after adding sodium bicarbonate, 79 ° C at the end of evaluation after 30 minutes, and the temperature of the evaluation solution after adding sodium bicarbonate was kept almost constant. It was.

  The theoretical total carbonic acid concentration in the 10% by weight sodium bicarbonate solution is 5.2% by weight, but immediately after dissolution, the measured value shows a residual ratio of almost 95% or more and hardly decreases. It was found that reduction of carbon dioxide in the state cannot be expected.

(2) Confirmation with high-concentration coffee liquid (effect of temperature, stirring, time, concentration)
Heated ion-exchanged water and coffee extract were put into a 1-liter beaker, and a predetermined amount of high-concentration coffee liquid was prepared by stirring and adjusted to a predetermined temperature shown in Table 1. While stirring the high-concentration coffee liquid, a predetermined amount of a sodium bicarbonate solution was added to adjust the pH. The high-concentration coffee liquid was kept warm with a hot stirrer and a heat-retaining material, and the rotation speed of the stirrer was 500 rpm and 250 rpm with 1000 rpm as a reference. The temperature of the high-concentration coffee liquid immediately after pH adjustment was adjusted to approximately 80 ° C., 70 ° C., 50 ° C., and 25 ° C. Table 1 shows the experimental conditions of the experimental example.

* The concentration of baking soda was set to 1500 ppm when all products were made.
The sodium bicarbonate solution was used at 75 ° C.

  When the baking soda solution is added to the high-concentration coffee liquor, bubbles are formed. The foaming was remarkable. Moreover, it turned out that the foam | bubble disappearance time is so early that foaming is remarkable. On the contrary, when the temperature was low (Experimental Example 6) or when the stirring was weak (Experimental Example 4), bubbles did not occur in a short time, but occurred for a long time. From these facts, it was found that the reaction in which carbon dioxide gas is generated proceeds faster when the mixture is stirred strongly at a high temperature.

  For each experimental example, the pH and carbon dioxide concentration of the high-concentration coffee liquor were evaluated. FIG. 2 shows the effect of temperature (Experimental Examples 1, 2, 5 and 6), FIG. 3 shows the effect of stirring (Experimental Examples 2, 3, and 4), and FIG. 4 shows the effect of elapsed time after the addition of sodium bicarbonate (Experimental Example 7). Indicates. The evaluation was performed after confirming that the bubbles disappeared. The pH before adding the sodium bicarbonate solution was 4.65.

  2, 3, and 4, it was found that the higher the temperature, the stronger the stirring, and the longer the time, the lower the total carbonic acid concentration. Moreover, it turned out that pH raises with the fall of a total carbonic acid concentration, and the dissolved carbon dioxide gas concentration as a single molecule also falls simultaneously. In addition, since addition of baking soda exists in adjustment of pH, when pH rose more than needed, it turned out that what is necessary is just to adjust the addition amount of baking soda suitably.

  In coffee beverages, from the viewpoint of flavor retention, it is not preferable to increase the time at a high temperature. Therefore, in Experimental Examples 1 to 7, the concentration of the high-concentration coffee liquor was set to a concentration that was diluted 5 times at the time of the product.・ 9 ・ 10). FIG. 5 shows changes in carbon dioxide concentration and pH after the addition of sodium bicarbonate. In FIG. 5, since the coffee extract concentration is different, the vertical axis represents the residual rate relative to the total carbonic acid concentration derived from baking soda.

  As can be seen from FIG. 5, it was found that the higher the concentration of the high-concentration coffee liquor, the shorter the carbon dioxide concentration can be reduced. However, no difference was observed after about 10 minutes.

  From the above experiments, it is difficult to reduce the carbon dioxide concentration in the baking soda solution. Stirring at high speed while the concentration and temperature of the high-concentration coffee liquor is high can achieve a reduction in the concentration of carbon dioxide brought in in a short time. And found to be effective. The effects of increasing the temperature include the effect of accelerating the carbon dioxide gas generation reaction when baking soda is added to the high-concentration coffee liquor, the effect of preventing the dissolution of carbon dioxide gas, the defoaming effect of bubbles, It became clear that it was effective for removal. Moreover, it is thought that the effect which raises the density | concentration of strong stirring and a high concentration coffee liquid has the effect of accelerating | stimulating the carbon dioxide generation reaction. That is, in actual scaled-up preparation, it is considered that temperature, stirring, time, and concentration are more remarkably effective or affected. Next, it confirmed by the Example.

[Plastic container]
1. Plastic cup (outer side) polypropylene (630 μm) / adhesive layer (30 μm) / ethylene-vinyl alcohol copolymer (180 μm) / adhesive layer (30 μm) / polypropylene (630 μm) (inner side) multilayer plastic sheet (1 0.5 mm) was vacuum-formed, and a plastic cup having a full inner capacity of 225 ml with a tapered side wall with a flange formed at the opening was manufactured.
The dimensions of each part of the plastic cup were a flange outer diameter of 76 mm, an opening inner diameter of 73 mm, a bottom diameter of 48 mm, and a height of 94 mm.

2. Sealing material A multilayer film comprising a polypropylene film (30 μm) / adhesive layer (3 μm) / aluminum foil (20 μm) / adhesive layer (4 μm) / biaxially stretched polyethylene terephthalate film (12 μm) from the lower layer was used as the sealing material.

[Evaluation]
1. The amount of carbon dioxide in the headspace The amount of headspace gas was collected in a saturated saline solution at 25 ° C. adjusted to pH 4 or less, and the volume was evaluated. Further, the carbon dioxide concentration was measured by gas chromatography, and the amount of carbon dioxide was determined from the headspace gas. In addition, evaluation was performed 3 cups per condition, and the average value was evaluated.

2. Hot warmer test
There is a rapid heating mode as a severe heating condition in a PET bottle warmer (DC-P75) manufactured by Tanix Co., Ltd. This is to switch the hot plate to the high temperature setting when a large number of low temperature containers are charged at once, and it continues for 80 minutes. After heating in this rapid heating mode, the bottom of the container swelled and became poorly seated. Moreover, the thing which the heat seal part of the lid | cover material retreated and the thing which became poor in sealing was made into the defect. The n number was 3 cups.

[Example 1]
3.2 kg of extract (concentrated coffee extract) was charged into a 50 L heat-stabilized mixing tank containing 15.3 kg of hot water maintained at 90 ° C. and stirred at a high speed of 200 rpm. The temperature of the high-concentration coffee liquid after the extract was diluted uniformly was 75 ° C. and the pH was 4.6. To this, 1.5 kg of a 10% by weight sodium bicarbonate solution at 75 ° C. was charged all at once. After charging, the high-concentration coffee liquor foamed and the foam disappeared in 2 to 3 minutes. The mixture was stirred for 5 minutes to remove the carbon dioxide gas derived from baking soda, and then cooled to 25 ° C. while diluting the coffee liquid four times with ion-exchanged water, and supplied to a 200 L tank. While stirring, granulated sugar and raw milk were added and dissolved, and finally adjusted to a 5-fold dilution to obtain a coffee drink with milk.
This milk-containing coffee drink is heated to 60 ° C., and 180 g is filled in the plastic cup. Then, the head space is replaced with a mixed gas of 75% nitrogen gas and 25% carbon dioxide gas, and the flange portion of the cup container The sealing material was heat-sealed to produce a container-filled low-acid beverage comprising a plastic container, and subjected to retort sterilization at 125 ° C. for 15 minutes (F0 = 35).
Table 2 shows the results of evaluating the container-packed low-acid beverage after retort sterilization.

[Example 2]
In Example 1, the prepared milk-containing coffee was sterilized at 145 ° C. for 9 seconds using a heat exchanger, and cooled to 25 ° C., except that a plastic cup and lid material preliminarily sterilized with a drug were used. Similarly, a container-packed low-acid beverage was produced and evaluated.

[Example 3]
In Example 1, a container-filled low-acid beverage was produced and evaluated in the same manner except that the filling temperature of the blended coffee with milk was 70 ° C. and the headspace was replaced with nitrogen gas alone.
In this example, since carbon dioxide derived from the mixed gas does not exist in the head space gas replacement, the total amount of carbonic acid in the container was smaller than that in Example 1.

[Comparative Example 1]
In Example 1, a container-packed low-acid beverage was produced and evaluated in the same manner except that the concentration of the high-concentration coffee liquid was changed to 1.5 times at the final product stage. In addition, by changing the concentration (dilution ratio), a mixing tank with a 100 L heat-retaining function was used, and the blending was 62 kg (85 ° C.) of hot water, 3.2 kg of extract, 1.5 kg of 10 wt% sodium bicarbonate solution. (75 ° C.).
In pH adjustment, stirring was performed under the same conditions as in Example 1. However, the amount of the sodium bicarbonate solution was poor due to the increase in volume, and foaming was small, but foaming occurred even after 5 minutes had elapsed after addition.

[Comparative Example 2]
In Example 1, the container-packed low-acid beverage was similarly produced and evaluated except that the temperature of the high-concentration coffee liquid was 25 ° C. and the baking soda solution was added without stirring the coffee liquid in the storage tank.
In the pH adjustment, stirring was performed under the same conditions as in Example 1. However, although the temperature of the high-concentration coffee liquid was 30 ° C. or less and mixing of the baking soda solution was good, foaming after addition was small, but foaming occurred even after 5 minutes. Had occurred.

[Comparative Example 3]
In Example 1, just before adding granulated sugar and raw milk, that is, in the state of low-concentration coffee liquid at 25 ° C. (diluted state), except that the pH was adjusted by low-speed rotation, a container-packed low-acid beverage was similarly prepared. Manufactured and evaluated.

* The total amount of carbonic acid in the container was evaluated as the residual rate relative to the total amount of carbonic acid derived from the added sodium bicarbonate.

Claims (12)

  In a low-acid beverage packed in a container adjusted to pH with baking soda, the concentration of carbon dioxide gas per unit volume of the headspace when collected in a saturated saline solution having a pH of 4 or less is 10% or less when stored at 25 ° C, and stored at 75 ° C Container-packed low-acid beverage characterized by being 20% or less by time.   The container-packed low-acid beverage according to claim 1, wherein the total amount of carbonate in the container after filling and sealing is 45% or less with respect to the total amount of carbonate determined from the amount of sodium bicarbonate added.   The container-packed low-acid beverage according to claim 1 or 2, wherein the head space is replaced with a mixed gas of nitrogen gas and carbon dioxide gas during filling.   The container-packed low-acid beverage according to any one of claims 1 to 3, wherein the low-acid beverage is a coffee beverage or a tea beverage.   The container is a plastic bottle, a plastic cup, or a metal can, The container-packed low-acid drink in any one of Claims 1-4.   In a method for producing a container-packed low-acid beverage whose pH is adjusted with sodium bicarbonate, sodium bicarbonate is added to a high-concentration, high-temperature, low-acid beverage, stirred to remove carbon dioxide from the sodium bicarbonate, and then the beverage is diluted to prepare a formulation. A method for producing a container-filled low-acid beverage, characterized in that the container is filled and sealed in a container.   The manufacturing method of the container-packed low-acid drink whose density | concentration of the said low-acid drink is 2 times or more of the density | concentration after dilution, and pH is 6 or less.   The method for producing a container-packed low-acid beverage according to claim 6 or 7, wherein the temperature of the low-acid beverage is 50 ° C or higher.   The method for producing a container-packed low-acid beverage according to any one of claims 6 to 8, wherein the amount of carbonate derived from baking soda after filling and sealing is 45% or less relative to the total amount of carbonate determined from the amount of sodium bicarbonate added.   The method for producing a container-packed low-acid beverage according to any one of claims 6 to 9, wherein the head space is replaced with a mixed gas of nitrogen gas and carbon dioxide during filling.   The method for producing a container-packed low-acid beverage according to any one of claims 6 to 10, wherein the low-acid beverage is a coffee beverage or a tea beverage.   The method for producing a container-packed low-acid beverage according to any one of claims 6 to 11, wherein the container is a plastic bottle, a plastic cup or a metal can.