JP2022158609A - Rich-flavor soy sauce and process for producing the same - Google Patents

Abstract

To provide a rich-flavor soy sauce that has high nitrogen concentration and excellent umami, savor and flavor, and to provide a process for producing the same.SOLUTION: A raw material soy sauce comprising a desalted or low-salt soy sauce is brought into contact with a salt water having a salt concentration higher than that of the raw material soy sauce through a forward osmosis membrane 1, and the water content of the raw material soy sauce is migrated to the salt water by forward osmosis membrane method, and the rich-flavor soy sauce containing a total nitrogen concentration of higher than 3.0 w/v%, 2-phenylethanol by 3.0 mg/L or more, isobutyl alcohol by 7.0 mg/L or more, and isoamyl alcohol by 5.0 mg/L or more is obtained.SELECTED DRAWING: Figure 1

Description

The present invention relates to a thick soy sauce containing more nitrogen-containing components than koikuchi soy sauce and usukuchi soy sauce, and a method for producing the same.

Rich soy sauce refers to soy sauce with a higher concentration of nitrogen compared to the general ``koikuchi soy sauce'' and ``usukuchi soy sauce''. This includes ``saishikomi soy sauce,'' which is fermented and matured again by adding ingredients such as soy sauce. The above-mentioned "tamari soy sauce" and "saishikomi soy sauce" are produced by the brewing method, but conventionally, methods for obtaining thick soy sauce by concentrating soy sauce produced by ordinary methods have also been proposed (e.g. , see Patent Documents 1 to 3).

For example, in the method for producing thick soy sauce described in Patent Document 1, a centrifugal thin film vacuum evaporator is used to evaporate low-salt soy sauce to a nitrogen concentration of 2.5% or more and a ratio of salt concentration to nitrogen concentration of 2 to 2. Concentrate to 6. In addition, in the method for producing thick soy sauce described in Patent Document 2, in order to obtain light-colored thick soy sauce, light-colored soy sauce having a chromaticity of 32 or more per nitrogen concentration of 1.0 w / v% is used as a raw material and pressure is reduced. It is concentrated. On the other hand, in the method for producing soy sauce described in Patent Document 3, soy sauce is treated with an NF membrane having a salt blocking rate of 5 to 25% in order to obtain soy sauce that satisfies the three conditions of light color, richness, and low salt. The permeated liquid is concentrated with an NF membrane having a salt rejection rate of 60% or more.

JP-A-2-219559 Japanese Unexamined Patent Application Publication No. 2002-27944 Japanese Patent Application Laid-Open No. 2006-212023

However, the above-described conventional method for producing thick soy sauce has the following problems. The nitrogen concentration of thick soy sauce produced by brewing methods such as “tamari soy sauce” and “saishikomi soy sauce” is about 3 w/v% at the highest, and it is difficult to increase the nitrogen concentration any further. On the other hand, if a vacuum concentration method or a membrane concentration method is used as in the methods described in Patent Documents 1 to 3, it is possible to produce concentrated soy sauce with a nitrogen concentration exceeding 3 w/v%, but soy sauce is concentrated under reduced pressure. As a result, there is a problem that the aromatic components are reduced and the aroma and flavor are deteriorated. Moreover, the concentration by the NF membrane has a problem that the amino acids are not concentrated and the umami is insufficient.

Accordingly, an object of the present invention is to provide a thick soy sauce having a high nitrogen concentration and excellent umami, flavor and flavor, and a method for producing the same.

The concentrated soy sauce according to the present invention is a soy sauce obtained by concentrating desalted soy sauce or low-salt soy sauce, having a total nitrogen concentration higher than 3.0 w/v% and containing 3.0 mg of 2-phenylethanol. /L or more, isobutyl alcohol of 7.0 mg/L or more, and isoamyl alcohol of 5.0 mg/L or more.
The concentrated soy sauce of the present invention may have a salt concentration higher than 4 w/v%.

In the method for producing thick soy sauce according to the present invention, a raw soy sauce made of desalted soy sauce or low-salt soy sauce is brought into contact with a high-concentration saline solution having a salt concentration higher than that of the raw soy sauce through a forward osmosis membrane. A concentration step is performed to transfer the water content of the raw material soy sauce to a saline solution by a permeation membrane method, and the total nitrogen concentration is higher than 3.0 w/v%, and 2-phenylethanol is 3.0 mg/L or more, and isobutyl alcohol. to obtain a soy sauce containing 7.0 mg/L or more of and isoamyl alcohol of 5.0 mg/L or more.
In the method for producing concentrated soy sauce of the present invention, soy sauce is brought into contact with a low-concentration saline solution having a salt concentration lower than that of the soy sauce through an ion-exchange membrane, and the salts in the soy sauce are converted into the saline solution by electrodialysis. A desalting step for migration may be performed, and the desalted soy sauce desalted in the desalting step and the salted brine may be used as the raw soy sauce and the highly concentrated brine in the concentration step, respectively.

In addition, the "total nitrogen concentration" in the present invention is a value measured by the method described in "Article 8 of the Japanese Agricultural Standards for soy sauce (measurement method) total nitrogen content 2 combustion method", "2-phenylethanol content" , "Isobutyl alcohol content" and "Isoamyl alcohol content" are obtained by the methyl acetate extraction method using gas chromatography (Nobutake Nunomura, Masaoki Sasaki, "Soy Sauce from the Perspective of Flavor Components", Hishioken , 1998, Vol.24, No.4, p.212, "III Quantitative determination of flavor components 1. Extraction method"). Article (Method of measurement) Salt-free soluble solid content 2 Measurement of salt content (2) Titration a. Potentiometric titration”. Also, "w/v %" is "mass volume %" and represents the mass of the solute contained in 100 mL of the solution in g.

According to the present invention, since the total nitrogen concentration can be increased without reducing the amount of flavor components and amino acids, the total nitrogen concentration is higher than 3.0 w / v%, and the thick soy sauce is excellent in umami, flavor and flavor. is obtained.

1 is a conceptual diagram showing a method for producing thick soy sauce according to the present embodiment; FIG. FIG. 4 is a conceptual diagram showing a method for producing thick soy sauce according to a modification of the present embodiment; 1 is a schematic diagram showing the configuration of a forward osmosis concentrator used in Example 1. FIG. It is a diagram showing the permeation rate of a forward osmosis membrane, with the horizontal axis representing time and the vertical axis representing the amount of liquid in a feed liquid tank. 3 is a schematic diagram showing the configuration of a concentrator used in Comparative Example 2. FIG.

EMBODIMENT OF THE INVENTION Hereinafter, the form for implementing this invention is demonstrated in detail with reference to attached drawings. In addition, this invention is not limited to embodiment described below.

The concentrated soy sauce according to the embodiment of the present invention is obtained by concentrating desalted soy sauce or low-salt soy sauce, has a total nitrogen concentration higher than 3.0 w/v%, and contains 3.0 mg of 2-phenylethanol. /L or more, isobutyl alcohol of 7.0 mg/L or more, and isoamyl alcohol of 5.0 mg/L or more. Here, "desalted soy sauce" is soy sauce obtained by desalting general soy sauce using a desalting device such as an ion exchange membrane to reduce the salt content. Also, "low-salt soy sauce" is low-salt soy sauce brewed at a low salt concentration, and has a salt concentration of 15 w/v% or less.

[Total nitrogen concentration: greater than 3.0 w/v%]
The total nitrogen concentration (total nitrogen content) is a value indicating the amount of nitrogen-containing compounds such as amino acids contained in soy sauce, and is used as an index of umami components. Common soy sauces such as Koikuchi soy sauce and Usukuchi soy sauce have a total nitrogen concentration of about 1.1 to 1.6 w/v%, while Saishikomi soy sauce has a total nitrogen concentration of about 1.6 to 2.5 w/v%. is 1.6 to 3.0 w/v%. On the other hand, the thick soy sauce of the present embodiment achieves a total nitrogen concentration exceeding 3.0 w/v% by concentrating desalted soy sauce or low-salt soy sauce by a forward osmosis concentration method. As a result, thick soy sauce containing a large amount of umami components such as amino acids can be obtained.

[Aroma component]
2-Phenylethanol, isobutyl alcohol, and isoamyl alcohol are aroma components that improve the flavor of soy sauce. Contains 0 mg/L (ppm) or more and 5.0 mg/L (ppm) or more of isoamyl alcohol. As a result, the fresh aroma of soy sauce can be felt sufficiently, and a rich soy sauce with good flavor can be obtained. On the other hand, if the concentration of 2-phenylethanol, isobutyl alcohol or isoamyl alcohol is less than the above range, the soy sauce will be inferior in aroma and flavor.

In addition to the components described above, the concentrated soy sauce of the present embodiment contains n-butyl alcohol, HEMF (4-Hydroxy-2(or 5)-ethyl-5(or 2)-methyl-3( 2H)-furanone), HMMF (4-Hydroxy-5-methyl-3(2H)-furanone), and the like.

[Salt concentration: more than 4 w / v%]
Since the thick soy sauce of the present embodiment is obtained by concentrating the raw material soy sauce, the amount of salt contained is greater than that of the raw material desalted soy sauce and low-salt soy sauce, and the salt concentration is 4 w/v%. higher than It should be noted that the salt concentration of the thick soy sauce of this embodiment varies depending on the salt content of the raw material soy sauce, the degree of concentration, and the like.

[Production method]
Next, the method for producing thick soy sauce according to the present embodiment described above will be described. The thick soy sauce of the present embodiment is obtained by concentrating desalted soy sauce or low-salt soy sauce (hereinafter referred to as raw material soy sauce) by a forward osmosis membrane method.

FIG. 1 is a conceptual diagram showing the method for producing thick soy sauce according to this embodiment. As shown in FIG. 1, when producing the thick soy sauce of the present embodiment, the raw soy sauce and the high-concentration saline solution having a salt concentration higher than that of the raw soy sauce are brought into contact with each other through the forward osmosis membrane 1, and the forward osmosis membrane method is used. A concentration process is performed to transfer the water content of the raw material soy sauce to the salt water. As a result, the raw soy sauce is dehydrated to obtain thick soy sauce, and the highly concentrated saline solution is diluted to discharge the diluted saline solution.

The concentration of the high-concentration salt solution used in this concentration step can be appropriately set according to the salt concentration of the raw material soy sauce. is preferably in the range of 3 to 5 w/v%. Thereby, the dehydration (concentration) efficiency can be improved.

Although the structure of the forward osmosis membrane 1 used in the concentration step is not particularly limited, for example, a flat membrane, a hollow fiber membrane, a tubular membrane, a spiral membrane, and the like can be used. In addition, the material of the forward osmosis membrane 1 is not particularly limited, and for example, a membrane formed of cellulose triacetate, polyamide, polysulfone, or the like can be used, and a composite polyamide membrane in which aquaporin is arranged is particularly suitable. . Since the composite polyamide membrane in which the aquaporins are arranged has a high affinity for water, the dehydration rate in the concentration process can be increased by using this as the forward osmosis membrane 1 .

Since the forward osmosis membrane method is a method of transferring water using a difference in osmotic pressure, the pressure applied to the membrane may be only the pressure required for liquid transfer. For this reason, the concentration process using the forward osmosis membrane method can reduce the energy required for concentration (dehydration) compared to the dehydration method using the reverse osmosis membrane method, and the membrane clogs and breaks. Since it is difficult to perform, it can be performed continuously for a long time. In addition, the use of the forward osmosis membrane method eliminates the need for heating, so deterioration of flavor components and loss of flavor components due to concentration treatment can be suppressed.

In addition, in the method for producing thick soy sauce of the present embodiment, a desalting step of obtaining desalted soy sauce by desalting ordinary soy sauce using an ion-exchange membrane may be performed separately from the concentration step described above. FIG. 2 is a conceptual diagram showing a method for producing thick soy sauce according to a modification of the present embodiment. In the manufacturing method of this modified example, as shown in FIG. A desalting step is performed to transfer the salts in the soy sauce to a low-concentration saline solution, and the desalted soy sauce desalted in this desalting step is used as raw material soy sauce in the concentration step described above.

The low-concentration saline solution used in the desalting step may be prepared separately, but the diluted saline solution discharged in the concentration step can also be used. This diluted saline solution (low-concentration saline solution) is salted in the desalting step to increase the salt concentration, and is discharged as a high-concentration saline solution, so that it can be used again in the concentration step. Note that the concentration step and the desalting step described above can also be performed in parallel.

As described in detail above, the concentrated soy sauce of the present embodiment is obtained by concentrating desalted soy sauce or low-salt soy sauce by a forward osmosis membrane method, has a total nitrogen concentration higher than 3.0 w/v%, and , contains 2-phenylethanol of 3.0 mg / L or more, isobutyl alcohol of 7.0 mg / L or more, and isoamyl alcohol of 5.0 mg / L or more, which are the aroma components, so the conventional product manufactured by the concentration method Compared to thick soy sauce, it has excellent umami, flavor and flavor, and even with thick soy sauce having a high nitrogen concentration, the fresh aroma of soy sauce can be felt sufficiently.

EXAMPLES Hereinafter, the effects of the present invention will be specifically described with reference to examples and comparative examples.

<Example 1>
First, as Example 1, raw soy sauce was concentrated by a forward osmosis membrane method to produce a thick soy sauce within the scope of the present invention. 3 is a schematic diagram showing the configuration of the forward osmosis concentrator used in Example 1. FIG. FIG. 4 is a diagram showing the permeation rate of the forward osmosis membrane, with the horizontal axis representing time and the vertical axis representing the amount of liquid in the feed liquid tank.

In this example, using the forward osmosis concentrator 10 shown in FIG. 3, low-salt soy sauce was concentrated to produce thick soy sauce. At that time, for the forward osmosis membrane module 11, an aquaporin/polyamide composite forward osmosis membrane module HFF02 manufactured by AQUAPORIN was used. This forward osmosis concentrator 10 has a configuration in which a feed liquid 17 flows into the hollow fibers of a forward osmosis membrane module 11 and a draw liquid 18 flows into the housing side, and the feed liquid 17 is separated by utilizing the osmotic pressure difference. concentrated.

In this embodiment, the flow rate and pressure of the feed liquid 17 and the draw liquid 18 are controlled by adjusting the output of the feed liquid transfer pump 14 and the draw liquid transfer pump 15 and the valves in the piping. FIG. 3 shows a device in which the forward osmosis membrane module 11 is placed vertically and the feed liquid 17 and the draw liquid 18 are co-flowed from the lower inlet. It is not limited. Furthermore, in the forward osmosis concentrator 10, the concentration gradient occurs in the liquids stored in the feed liquid tank 12 and the draw liquid tank 13 as the concentration progresses. The liquid inside was stirred.

In this embodiment, the feed liquid 17 is reduced-salt soy sauce having a salt concentration of 5.1 w/v% and a nitrogen concentration of 1.8 w/v% obtained by desalting this brewed soy sauce with an electrodialysis membrane. was used. Then, 5.5 L of this reduced-salt soy sauce is put into the feed liquid tank 12 of the forward osmosis concentrator 10 shown in FIG. was concentrated. At that time, the feed liquid inlet flow rate was 1 L/min, the draw liquid inlet flow rate was 0.4 L/min, the feed liquid inlet pressure was 0.2 to 1.4 bar, and the draw liquid inlet pressure was 0 bar.

At the time of concentration, as shown in FIG. 4, the permeation speed was determined from the liquid level in the feed liquid tank 12, and salt was appropriately introduced into the draw liquid tank 13 according to the decrease in the permeation speed. Concentration was terminated when the amount of permeation stopped changing. As a result, soy sauce (thick soy sauce) concentrated to 2.0 times (2.75 L) by volume and 4 L of draw liquid (salt solution) were obtained. The draw liquid (salt solution) after the concentration was colorless and transparent, and although the scent of soy sauce was not confirmed, it had a slight alcohol odor. The concentration was 1.06 v/v% (volume %).

<Comparative Example 1>
Next, the soy sauce of Comparative Example 1 was produced by concentrating the raw material soy sauce by a vacuum concentration method. Specifically, low-salt soy sauce with a salt concentration of 5.1 w/v% and a nitrogen concentration of 1.8 w/v% obtained by desalting this brewed soy sauce with an electrodialysis membrane was centrifuged by Okawara Seisakusho Co., Ltd. Using a thin-film vacuum evaporator, Evapol, the soy sauce was concentrated under reduced pressure conditions of an evaporation temperature of 50° C. and an operating pressure of 12 kPa to obtain soy sauce concentrated 2.3 times on a volume basis.

<Comparative Example 2>
Next, the soy sauce of Comparative Example 2 was produced by concentrating the raw material soy sauce using an NF membrane (nanofiltration membrane). FIG. 5 is a schematic diagram showing the configuration of a concentrator used when producing soy sauce in Comparative Example 2. FIG. In the NF membrane concentration apparatus 20 shown in FIG. 5, the NF membrane 21 is arranged on the bottom surface of the test cell 22, the NF membrane 21 is supported by the support 24, and the liquid permeable part 27 is provided around the support 24. ing. A stirrer 26 for stirring the concentrated liquid 23 is provided in the test cell 22 .

In this comparative example, a reduced-salt soy sauce having a salt concentration of 5.1 w/v% and a nitrogen concentration of 1.8 w/v% obtained by desalting the soy sauce with an electrodialysis membrane was used. Then, 100 ml of this reduced-salt soy sauce is placed in the test cell 22 of the NF membrane concentrator 20 shown in FIG. Concentrated soy sauce. At that time, as the test cell 22, a batch type test cell C70 manufactured by Nitto Denko Corporation was used, and as the NF membrane 21, NTR-759HR manufactured by Nitto Denko Corporation (salt blocking rate 90%, φ70) was used.

The liquid that permeates the NF membrane 21 due to pressure passes through the liquid permeable portion 27 and is stored in the liquid recovery container 28 . In this comparative example, the amount of the concentrated liquid was calculated backward from the amount of the permeated liquid stored in the liquid recovery container 28, and concentration was continued until the amounts of the permeated liquid and the concentrated liquid were the same, and the soy sauce of Comparative Example 2 was obtained.

[evaluation]
For each soy sauce of Example 1 and Comparative Examples 1 and 2, the "total nitrogen concentration (TN)", "salt concentration (NaCl)" and the amount of each flavor component were measured by the method described above, and by high performance liquid chromatography. Amino acid content was measured. The results are shown in Table 1 below. "ND" shown in Table 1 below is an abbreviation for "Not Detected" and indicates that the concentration is below the detection limit.

As shown in Table 1 above, the soy sauce of Comparative Example 1, which was concentrated under reduced pressure, decreased 2-phenylethanol, isobutyl alcohol, isoamyl alcohol and n-butyl alcohol among the aroma components. In addition, although the soy sauce of Comparative Example 2 concentrated with the NF membrane had a volume of 1/2, the total nitrogen concentration and amino acid concentration increased only about 1.3 times, and the components were sufficient. was not concentrated in Furthermore, the soy sauce of Comparative Example 2 had less aromatic components than the raw material soy sauce. On the other hand, the soy sauce of Example 1 obtained by concentration by the forward osmosis membrane method had a higher amount of flavor components and amino acids than the starting soy sauce.

From the above results, it was confirmed that according to the present invention, a soy sauce with a high umami taste, excellent flavor and flavor, and a sufficiently fresh aroma of soy sauce can be obtained.

1 Forward Osmosis Membrane 2 Ion Exchange Membrane 10 Forward Osmosis Concentrator 11 Forward Osmosis Membrane Module 12 Feed Liquid Tank 13 Draw Liquid Tank 14 Feed Liquid Transfer Pump 15 Draw Liquid Transfer Pump 16a, 16b, 26 Stirrer 17 Feed Liquid (Low Salt Soy Sauce )
18 draw liquid (salt solution)
20 NF Membrane Concentrator 21 NF Membrane 22 Test Cell 23 Concentrated Liquid 24 Support 25 Nitrogen Cylinder 27 Liquid Permeable Part 28 Liquid Recovery Container

Claims (4)

Soy sauce obtained by concentrating desalted soy sauce or low-salt soy sauce,
The total nitrogen concentration is higher than 3.0 w/v%,
A concentrated soy sauce containing 2-phenylethanol of 3.0 mg/L or more, isobutyl alcohol of 7.0 mg/L or more, and isoamyl alcohol of 5.0 mg/L or more. The thick soy sauce according to claim 1, wherein the salt concentration is higher than 4 w/v%. Raw material soy sauce made of desalted soy sauce or low-salt soy sauce is brought into contact with a high-concentration saline solution having a salt concentration higher than that of the raw material soy sauce through a forward osmosis membrane, and water in the raw material soy sauce is removed by the forward osmosis membrane method. Having a concentration step of transferring to water,
To obtain a soy sauce having a total nitrogen concentration higher than 3.0 w/v% and containing 2-phenylethanol of 3.0 mg/L or more, isobutyl alcohol of 7.0 mg/L or more, and isoamyl alcohol of 5.0 mg/L or more. A method for producing thick soy sauce. A desalting step of contacting soy sauce with a low-concentration saline solution having a lower salt concentration than the soy sauce through an ion-exchange membrane, and transferring the salts in the soy sauce to the saline solution by electrodialysis;
4. The method for producing thick soy sauce according to claim 3, wherein the desalted soy sauce desalted in the desalting step and the salted brine are used as the raw material soy sauce and the highly concentrated brine in the concentration step, respectively.

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