JPH11178534A - Reduction of sodium concentration in plum juice, and production of plum juice drink - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for reducing the concentration of sodium in a plum vinegar or a desalinized plum juice, and further to provide a method for producing a plum juice drink having decreased sodium concentration and increased potassium concentration from the plum juice using the plum vinegar as a starting raw material. SOLUTION: A strong acid is added to a plum juice in a desalinizing treatment or the plum juice after desalinization, and the plum juice with the strong acid is treated with an ion-exchange membrane electrodialysis. A potassium source is added to the obtained plum juice with a reduced sodium concentration in the method for producing the plum juice drink.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for reducing the sodium concentration in plum juice, and more particularly, to an improved method for reducing the sodium concentration in plum juice obtained by desalting ume vinegar by ion exchange membrane electrodialysis. And a method for producing a plum juice beverage having a low sodium concentration and a high potassium concentration.

[0002]

2. Description of the Related Art Plum juice, which has not only a peculiar aroma and flavor but also a pharmacological action peculiar to plums, has been attracting attention as a palatable beverage and a healthy beverage.
Traditionally, plum vinegar, a by-product of the manufacturing process of dried plums, has been diluted and consumed.In recent years, plum fruit juice obtained by squeezing plum fruit and plums obtained by desalting plum vinegar are desalted. Drinks containing fruit juice and the like are commercially available.

[0003] As a method of squeezing plum fruit, plum fruit is crushed and pulverized, an enzyme is acted on to reduce the amount of pectin, then pulp is removed by a centrifugal separator and squeezed and filtered. Crushed-filtration method to obtain plum fruit juice, and frozen squeezing method to obtain plum juice by rapidly freezing plum fruit, leaving it for a certain period of time, thawing and pressing. In the present invention, plum juice produced by squeezing plum fruit is referred to as “pressed plum juice”.

On the other hand, plum vinegar is a liquid containing components eluted from plum by-produced when salted plum fruit is pickled in the process of producing dried plum, and high concentration of salt. Japanese Patent Publication No. 57-24103
Japanese Patent Laid-Open Publication No. 2000-210, proposes a method for producing a natural plum acidulant in which salt in plum vinegar is desalted by electrodialysis using an ion exchange membrane. In the present invention, the plum juice obtained by treating plum vinegar by ion exchange membrane electrodialysis or the like and desalinating it is referred to as "desalted plum juice".
Called.

[0005] Compressed plum juice and desalted plum juice are both p
H is about 2.0 to 3.0 and a component of plum, for example, a low-boiling component constituting an aroma such as ethyl acetate and ethanol, an organic acid component such as citric acid and malic acid, an amino acid, a lipid, a saccharide, and calcium , Potassium, sodium, phosphorus, iron, etc.

In general, it is said that excessive intake of sodium causes not only arteriosclerosis and hypertension but also cancer. On the other hand, potassium is contained in plant foods in a relatively large amount, and it is known that sodium is accompanied when potassium is excreted from the human body.

[0007] Atomic absorption spectrometry analysis of potassium concentration and sodium concentration in the pressed plum juice and desalted plum juice shows that the potassium concentration of the desalted plum juice is lower than that of the pressed plum juice, while This indicates that the concentration is higher than that of pressed plum juice.

[0008]

[Table 1]

As described above, pressed plum juice having a low sodium concentration and a high potassium concentration as a food can be said to be extremely balanced in terms of human health. on the other hand,
Direct ingestion of desalted plum juice having a high sodium concentration and a low potassium concentration has many problems in human health. Therefore, reducing the sodium concentration in the desalted plum juice to less than the above concentration, preferably to the sodium concentration of the pressed plum juice, is extremely important in terms of human health, but is effective in reducing the concentration. There is no known way.

[0010]

SUMMARY OF THE INVENTION The present invention provides a method for reducing the sodium concentration in plum juice, and a method for producing a health-balanced plum juice beverage having a low sodium concentration and a high potassium concentration. The purpose is to do.

[0011]

Means for Solving the Problems The present inventors have conducted intensive studies to achieve the above object, and as a result, the limit of the sodium concentration of plum juice that can be removed by the usual treatment using ion exchange membrane electrodialysis is as follows. The present invention was completed based on the view that sodium in fruit juice was bound to an organic acid such as citric acid and was not dissociated as free ions.

The present invention is a method for reducing the concentration of sodium in plum juice, which comprises adding a strong acid to desalted plum juice using plum vinegar as a starting material and treating the resultant by ion exchange membrane electrodialysis. Further, the present invention is a method for producing a plum juice beverage, characterized by adding a potassium source to the plum juice having a reduced sodium concentration obtained by the above method.

[0013]

DETAILED DESCRIPTION OF THE INVENTION In the present invention, ume vinegar is composed of plum fruit components obtained as a by-product of the ume pickling step in the production of umeboshi, and usually a salt of approximately saturated concentration, ie, about 9%.
0-95 g / L sodium ion and about 140-150
pH of about 2.0 to 3.0 containing g / L of chloride ions.
0 liquid. The desalted plum juice using the above-mentioned plum vinegar as a starting material is the plum juice before and during the desalination treatment of the plum vinegar by ion exchange membrane electrodialysis, and the plum vinegar is subjected to ion exchange membrane electrodialysis, ion exchange resin, etc. It includes plum juice from which almost all of the salt content has been removed, that is, desalted plum juice as defined above, and concentrated desalted plum juice in which the desalted plum juice is further concentrated to 1/3 to 1/10.

In the present invention, the desalted plum fruit juice has a sodium content of sodium citrate of 1.
A strong acid of 0 to 1.5 equivalent times is added, and the pH after the addition is adjusted to 2.
It adjusts to less than 0, preferably 0.5-1.5, and processes by ion exchange membrane electrodialysis. Addition of a strong acid to plum juice binds to an organic acid such as citric acid to dissociate non-ionized sodium ions, and enables removal by ion exchange membrane electrodialysis. As the strong acid, a non-oxidizing inorganic strong acid certified as a food additive, for example, hydrochloric acid for food addition, phosphoric acid for food addition, or the like can be used, and hydrochloric acid for food addition is preferably used. In the ion-exchange membrane electrodialysis of desalted plum juice to which a strong acid has been added, when the sodium concentration is not sufficiently reduced, a strong acid is additionally added during the electrodialysis,
Electrodialysis may be continued.

The treatment by the ion exchange membrane electrodialysis in the present invention will be described in detail based on the ion exchange membrane electrodialysis apparatus shown in FIG. 1 showing one embodiment of the present invention. In FIG. 1, an ion exchange membrane electrodialysis apparatus includes an ion exchange membrane electrodialysis tank 11, a desalinated solution tank 20, a concentrated solution tank 24,
It is composed of circulation pumps 27 and 30, piping between these single devices and a DC power supply.

The ion exchange membrane electrodialysis tank 11 is
2, an anode 13, a cation exchange membrane 14 and an anion exchange membrane 15, alternately arranged between the cathode 12 and the anode 13,
A plurality of desalting chambers 18 separated by a cathode chamber 16, an anode chamber 17, a cation exchange membrane 14 and an anion exchange membrane 15;
And a plurality of concentration chambers 19.

The desalting solution tank 20 includes an inorganic acid adding line 21, a potassium source adding line 22, and desalting solution circulating lines 28 and 29 for circulating the desalinating solution through a circulating pump 27 in the desalting chamber 18. And the concentrate tank 24
Concentrate circulating lines 31, 3 for circulating the water supply line 25, the concentrate discharge line 26, and the concentrate through the circulating pump 30 through the cathode chamber 16, the anode chamber 17, and the concentrating chamber 19.
2 is plumbed. The cathode 12 and the anode 13 are connected to a DC power supply.

The main equipment such as the ion exchange membrane electrodialysis tank 11, the desalting liquid tank 20, the concentrated liquid tank 24, and the circulation pumps 27 and 30 and the piping between the single equipment are made of acid-resistant material such as polyvinyl chloride. For example, a rubber-lined metal material is used, and polyvinyl chloride is particularly preferably used. On the cathode 12 of the ion exchange membrane electrodialysis tank 11, iron, nickel, stainless steel, etc.,
The anode 13 is made of graphite, platinum, platinum-plated titanium, or the like. Cation exchange membrane 14 and anion exchange membrane 1
As 5, any of a homogeneous or heterogeneous polymerization system or condensation system can be used.

In the present invention, a strong acid is added to the desalted liquid tank 20 charged with the desalted plum juice, the pH is adjusted by stirring, and circulated through the circulation pump 27 to the cathode chamber 16 and the desalination chamber 18 while being concentrated. An electrolyte such as sodium chloride or sodium sulfate is charged into the liquid tank 24 to adjust the concentration of the electrolyte by filling water, and the electrolyte is circulated through the circulation pump 30 to the anode chamber 17 and the concentration chamber 19, and between the cathode 12 and the anode 13. By applying a direct current, the desalted plum fruit juice is subjected to a treatment by ion exchange membrane electrodialysis. In the above method, the ume vinegar can be desalted by treating ume vinegar in the same manner instead of desalted ume juice. Therefore, by first performing a desalination treatment of ume vinegar, and continuing the treatment by adding a strong acid to ume vinegar circulated during the treatment process, it is possible to obtain ume juice with a low sodium concentration directly from ume vinegar. .
The voltage between the cathode 12 and the anode 13 is 0.2 to 2.0 per pair of the cation exchange membrane 14 and the anion exchange membrane 15.
V, the current is adjusted to 0.1 to ^{3 A} per 1 dm ² of the ion exchange membrane.

In the process of desalting ume vinegar, the desalting chamber 1
The sodium ions and the hydrogen ions in 8 pass through the cation exchange membrane 14 to the cathode chamber 16 and the concentration chamber 19, and the chloride ions pass through the anion exchange membrane to the anode chamber 17 and the concentration chamber 19, and are removed. Salt in the plum vinegar circulating in the salt chamber 18 is removed.

In the desalting process of the ume vinegar, when the salt in the circulating desalting solution is almost completely removed, a strong acid is added to the desalting solution tank 20 from the inorganic acid addition line 21 to adjust the pH. adjust. On the other hand, when desalted plum juice or concentrated desalted plum juice is to be treated, the pH is adjusted by first adding a strong acid to the desalted liquid tank 20 in which they are charged.

In the treatment by ion exchange membrane dialysis, sodium ions and hydrogen ions, which have been dissociated by the addition of a strong acid, pass through the cation exchange membrane 14 and enter the anion of the added strong acid into the cathode chamber 16 and the concentration chamber 19. Moves through the anion exchange membrane to the anode chamber 17 and the concentration chamber 19,
Sodium in the plum juice circulating in the desalting chamber 18 is removed, and its concentration decreases. At the time when the sodium concentration and anion concentration in the plum juice fell below the predetermined concentration,
The treatment by the ion exchange membrane electrodialysis is terminated.

During the treatment, salt or sodium salt of a strong acid and a strong acid which has not contributed to the reaction are concentrated in the concentrate tank 24, so that water is supplied from the water supply line 25 to reduce the electrolyte concentration to zero. The concentration is adjusted within the range of 0.1 to 5.0% by weight, and the excess concentrate is discharged out of the system through the concentrate discharge line 26.

After completion of the above-mentioned treatment, a potassium source is added from the potassium addition line 22 to the plum juice having a reduced sodium concentration collected in the desalting solution tank 20 to adjust the potassium concentration and pH in the plum juice. Thus, a plum juice beverage having a reduced sodium concentration and an increased potassium concentration can be obtained. Examples of the potassium source include potassium-containing compounds certified as food additives, for example, potassium hydroxide for food supplementation and potassium carbonate for food supplementation, and potassium hydroxide is particularly preferred. These can be added as solids or aqueous solutions. When potassium hydrogen carbonate is used as a potassium source, a sparkling beverage is obtained.

[0025]

The present invention will be specifically described below with reference to examples. The pH of the plum juice in the examples is a value measured at 25 ° C., and the citric acid is a value containing ionized citric acid. Sodium and potassium are values measured by the atomic absorption method.

Example 1 (Treatment of Plum Vinegar without Salt Removal) In the ion exchange membrane electrodialyzer shown in FIG.
Stainless steel 2 and platinum-plated titanium anode 13 were used, and an effective area of 2.0 dm ² between each of 10 strong acid type cation exchange membranes and strong base type anion exchange membranes was alternately used. Ion exchange membrane electrodialysis tank 1 arranged
1 in the desalting chamber 18,
L ume vinegar circulation pump 27 and desalted liquid circulation line 2
8 and 29, while the cathode compartment 16, the anode compartment 17 and the concentration compartment 18 of the ion-exchange membrane electrodialysis tank 11.
Then, a 5 g / L aqueous sodium chloride solution charged into the concentrate tank 24 is circulated through the circulation pump 30 and the concentrate circulation lines 31 and 32, and a voltage of 7.0 V is applied between the cathode 12 and the anode 13. Was applied to start desalting of plum vinegar by electrodialysis. Water was supplied to the concentrate tank 24 so as to maintain the electrolyte concentration in the concentrate tank 24 at about 2 g / L simultaneously with the start of the treatment, and excess electrolyte aqueous solution was discharged out of the system through the concentrate discharge line 26.

The analysis values of the ume vinegar at the start of the treatment, and the analysis values of the samples from the desalted liquid tank 20 at 2.5 hours and 5.0 hours after the start of the treatment are shown in columns A, B and C of Table 2, respectively.
The sodium concentration and the chloride ion concentration in the ume vinegar before the start of the treatment are significantly reduced 2.5 hours after the start of the treatment, and the sodium concentration 5.0 hours after the start of the treatment after 2.5 hours has elapsed is 2. No change from the value after 5 hours was observed. This indicates that the desalting treatment of ume vinegar was almost completed 2.5 hours after the start of the treatment, and desalted ume juice was produced.

5.0 hours after the start of the treatment, the desalinated solution tank 2
Then, 10 ml of 35% by weight hydrochloric acid for food addition was added to 0, and energization was further continued for 1 hour to complete the treatment. The analysis value of the sample from the desalting solution tank 20 at the end of the treatment is shown in column D of Table 2. The sodium concentration in the obtained plum juice dropped from the value shown in column C of Table 2 to the value shown in D, indicating that sodium that could not be removed before the addition of the hydrochloric acid for food use was removed. .

Next, 3.5 g of potassium hydroxide for food addition was added to and dissolved in the plum juice collected in the desalting liquid tank 20 to obtain a plum juice drink having the analysis values shown in column E of Table 2. Column H of the same table shows the analysis values of the pressed plum juice as a reference. The sensory test results of the obtained plum juice beverage did not differ from the results of the pressed plum juice.

[0030]

[Table 2]

A: Plum vinegar at the start of the first dialysis treatment B: Plum juice at the end of the first dialysis treatment C: Plum juice at the start of the second dialysis treatment with 35% hydrochloric acid added to the plum juice of B D : Plum juice at the end of the second dialysis treatment E: Plum juice obtained by adding potassium hydroxide to D plum juice F: Pressed plum juice (see)

Example 2 Desalted plum juice produced by ion exchange membrane electrodialysis of ume vinegar was concentrated by low-temperature vacuum evaporation to prepare 1/5 concentrated desalted plum juice. Using the apparatus used in Example 1, 50 mL of 35% by weight of hydrochloric acid for food addition was added to 1.0 L of the obtained 1/5 concentrated desalted plum juice under the same current-carrying conditions as in Example 1. Time processing completed. 18.0 g of potassium hydroxide for food addition was added to and dissolved in the obtained plum juice to prepare a concentrated plum juice beverage.

1/5 concentrated desalted ume juice, ume juice after addition of hydrochloric acid for food addition, ume juice after 5 hours treatment, concentrated ume juice drink after addition of potassium hydroxide for food addition, and 1/5 concentrated press as reference Each of the analysis values of plum juice is shown in Table 3, A, B, C,
Shown in columns D and E. The sodium concentration in the 1/5 concentrated desalted plum juice decreases from the value shown in column B to the value shown in column C,
This indicated that sodium was removed with high efficiency. Also,
The analytical value of the concentrated plum juice beverage shown in column D is very similar to the analytical value of 1/5 concentrated pressed plum juice shown as a reference in column E,
No differences were found in the results of the sensory tests.

[0034]

[Table 3]

A: 1/5 concentrated desalted plum juice B: Plum juice at the start of dialysis treatment obtained by adding 35% by weight hydrochloric acid to A plum juice of A C: Plum juice at the end of dialysis treatment D: Water added to C plum juice of C Plum juice with added potassium oxide E: 1/5 concentrated pressed plum juice (see)

[0036]

According to the present invention, a strong acid is added to desalted ume juice to reduce the sodium concentration in the desalted ume juice, which was difficult to separate and remove only by desalting the ume vinegar by ion exchange membrane electrodialysis. In addition, it is possible to provide a very simple method in which the treatment is further performed by ion exchange membrane electrodialysis. Further, by adding a potassium source to the obtained plum juice having a reduced sodium concentration, a plum juice beverage having a good balance in health can be obtained. The present invention provides a method for removing sodium in plum vinegar and desalted plum juice and a method for producing a plum juice beverage in which the sodium concentration is reduced and the potassium concentration is increased using plum vinegar as a starting material, and its industrial significance. Is extremely large.

[Brief description of the drawings]

FIG. 1 is an illustration of an apparatus used in an embodiment of the present invention.

[Explanation of symbols]

 11: Ion exchange membrane electrodialysis tank 12: Cathode, 13: Anode 14: Cation exchange membrane 15: Anion exchange membrane 16: Cathode room 17: Anode room 18: Demineralization room 19: Concentration room 20: Demineralization solution tank 24: Concentrate tank 27, 30: Circulation pump

Claims (4)

[Claims] 1. A method for reducing the concentration of sodium in plum juice, comprising adding a strong acid to desalted plum juice using plum vinegar as a starting material and treating it by ion exchange membrane electrodialysis. 2. The desalted plum juice is a plum juice in the process of desalting ume vinegar by ion exchange membrane electrodialysis, a desalted ume juice obtained by desalinating ume vinegar, or a concentrated desalted ume juice obtained by concentrating the same. 2. The method for reducing the sodium concentration in plum juice according to 1. 3. The reduction of sodium concentration in plum juice according to claim 1, wherein a strong acid is added to the plum juice in the course of desalting treatment of ume vinegar by ion exchange membrane electrodialysis, and the treatment by ion exchange membrane electrodialysis is continued. Method. 4. A method according to claim 1, wherein a strong acid is added to desalted ume juice using ume vinegar as a starting material, and a potassium source is added to ume juice having a reduced sodium concentration obtained by treatment by ion exchange membrane electrodialysis. Of plum juice drink