JP7568441B2 - Seasoning liquid for herring roe - Google Patents

Description

The present invention relates to a seasoning liquid for seasoned herring roe. More specifically, the present invention relates to a seasoning liquid for seasoned herring roe that is suitable for seasoning herring roe sterilized with sodium chlorite.

Kazunoko has long been enjoyed as a food ingredient unique to Japan. In addition to salted kazunoko, kazunoko is also widely enjoyed as "seasoned kazunoko," which is made by soaking kazunoko in a seasoning liquid. In addition, Matsumae-zuke and Sankai-zuke, which are derivatives of seasoned kazunoko, are also known as popular ingredients. In the following, the term "kazunoko processed products" may be used to refer to kazunoko products such as salted kazunoko, seasoned kazunoko, Matsumae-zuke, and Sankai-zuke.

Seasoned herring roe is
(a) Salting process: A process of removing eggs from brooded herring, washing them with water, and salting them (the herring eggs after this process are called "salted herring eggs");
B) Sterilization step: a step of sterilizing the salted herring eggs with a disinfectant (the salted herring eggs after this step are referred to as "sterilized herring eggs");
C) Desalting and washing process: A process of immersing the sterilized herring eggs in salt water to remove the salt and remove residual sterilizing components (the sterilized herring eggs after this process are referred to as "salted herring eggs");
Next,
d) Seasoning process: The desalted herring roe is soaked in a seasoning liquid to produce seasoned herring roe.
To avoid confusion, below, the terms "kazunoko" and "seasoned kazunoko" will only refer to herring roe that have been processed into the final product, and the terms "herring roe" or simply "roe," such as "salted herring roe,""sterilized herring roe," and "de-salted herring roe," will be used to refer to raw materials and intermediate eggs before the final product.

In the above sterilization process, hydrogen peroxide water was once used at one time, but because an enzyme treatment (catalase decomposition) is required in the washing process to remove hydrogen peroxide remaining in the "sterilized herring eggs," the mainstream method now uses an aqueous solution of sodium chlorite as a disinfectant. Note that when sodium chlorite is used for sterilization, it is stipulated that "the sodium chlorite must be decomposed or removed before the final food is completed" ("Standards and Criteria for Foods, Additives, etc." (Ministry of Health and Welfare Notification No. 370, 1959)).

However, when using sodium chlorite for sterilization, there was a problem that even if the concentration of sodium chlorite in the herring roe was reduced to below the detection limit during the washing process, an unpleasant odor derived from the sterilizing agent tended to remain.
For this reason, in the above seasoning process, it was necessary to first soak the desalted herring roe in the seasoning liquid (pre-soaking), then replace the seasoning liquid and soak it a second time (main soaking). The "pre-soaking" was a factor in increasing material costs, incurring costs for disposing of the seasoning liquid, and reducing productivity.

As a method for removing the residual chlorine odor of chlorine-containing disinfectants, Japanese Patent Laid-Open Publication No. 3-130062 (Patent Document 1) proposes a method in which food treated with a chlorine-containing disinfectant is brought into contact with an organic acid alkali metal salt. In the examples, the document only describes an example in which sodium hypochlorite is used as a chlorine-containing disinfectant.

Japanese Patent Application Publication No. 3-130062

Therefore, when producing seasoned herring roe, the inventors followed the teachings of Patent Document 1 and sterilized salted herring roe with sodium chlorite, and then used sodium lactate as an organic acid alkali salt in an attempt to remove the chlorine odor, but found that the chlorine odor still remained in the seasoned herring roe.
Strictly speaking, the odor that remains after using sodium chlorite is thought to contain components other than chlorine, but for convenience, we will use the term "chlorine odor."
In light of the above circumstances, the inventors have furthered their research with the goal of establishing a method for producing seasoned herring roe that can eliminate the chlorine odor derived from sodium chlorite by simply immersing the herring roe in a seasoning liquid once, without the need for the previously mentioned "pre-soaking."

As a result, the inventors discovered that when sterilized herring eggs sterilized with sodium chlorite are washed until the sodium chlorite is below the detection limit, and then soaked in a seasoning liquid to obtain seasoned herring roe, the pH of the seasoning liquid used for soaking (the seasoning liquid before soaking) is set to 3.8 to 4.6, which allows efficient production of seasoned herring roe with reduced residual chlorine odor, and thus completed the present invention.

That is, the present invention relates to a seasoning liquid suitable for seasoned herring roe, characterized in that the pH is 3.8 or more and 4.6 or less.
Seasoned herring roe is usually shipped in a sealed container such as a polymer bag together with "salted herring roe" and about 0.5 to 0.8 times the weight of the seasoning liquid. Since the pH of "salted herring roe" is about 6.6, if the pH of the seasoning liquid used for pickling (soaking) is adjusted in advance to be lower than the pH of "salted herring roe", the pH of the seasoned herring roe and the pH of the seasoning liquid will reach equilibrium after pickling at a value between the initial pH of the salted herring roe and the initial pH of the seasoning liquid. Here, the equilibrium between the pH of the salted herring roe and the pH of the seasoning liquid means that the difference between the pH values of the two is 0.1 or less. The time required for equilibrium is 48 to 72 hours. The pH of seasoned herring roe refers to the pH of the juice obtained by grinding the herring roe, which has been drained of the seasoning liquid, in a mortar.
According to the present invention, salted herring eggs are sterilized with sodium chlorite to obtain sterilized herring eggs, which are then washed and desalted to obtain desalted herring eggs. The desalted herring eggs are then immersed in an appropriate amount of seasoning liquid with a pH of 3.8 or more and 4.6 or less, and the chlorine odor derived from the sterilizing agent can be removed with just one immersion without the need for a "pre-immersion".
In the above, if the seasoning liquid has a pH of less than 3.8, not only will the herring roe taste more sour, but the herring roe's protein will degrade, causing the surface of the herring roe to turn white or hard, resulting in the loss of the herring roe's unique texture, which is undesirable. On the other hand, if the seasoning liquid has a pH of more than 4.6, the seasoned herring roe will tend to have a chlorine odor derived from sodium chlorite, which is undesirable.

When preparing seasoned herring roe using the seasoning liquid of the present invention, it is preferable to appropriately adjust the weight ratio of herring roe to the seasoning liquid so that the pH of the final seasoned herring roe is 4.9 or more and 6.0 or less. If the pH of the seasoned herring roe exceeds 6.0, the chlorine odor from sodium chlorite will remain. On the other hand, if the pH is less than 4.9, the protein that forms the roe will be altered, impairing the product quality.

In order to adjust the pH of the seasoning liquid to 3.8 to 4.6, an organic acid is added to the seasoning liquid in an amount sufficient to impart the pH to the liquid. Examples of the organic acid include lactic acid, acetic acid, succinic acid, malic acid, citric acid, tartaric acid, and fumaric acid.
These organic acids may be chemically synthesized, fermented, or naturally derived. They may be used alone or in mixtures. Fermented products include, for example, brewed vinegar as an acetic acid source. Natural organic acid sources include citrus juice rich in succinic acid and malic acid.

As a modified example, the present invention can also be applied to the production of herring roe products using herring roe sterilized with sodium chlorite (sterilized herring roe) as a raw material.
For example, herring roe sterilized with sodium chlorite is washed and desalted in salt water whose pH has been adjusted to 3.8 to 4.6 by adding an organic acid, to obtain desalted herring roe without a chlorine smell. The desalted herring roe can be made into seasoned herring roe, salted herring roe, and other herring roe products. Other herring roe products include sankaizuke and matsumaezuke.

According to the present invention, the chlorine odor caused by sodium chlorite can be removed from seasoned herring roe made from herring roe sterilized with sodium chlorite.

FIG. 1 is a schematic flow diagram of a process for producing seasoned herring roe according to the prior art. FIG. 1 is a schematic flow diagram of a process for producing seasoned herring roe according to the present invention. FIG. 1 is a schematic flow diagram of a process for producing desalted herring roe by a modified method of the present invention.

The following examples illustrate aspects of the present invention.

[Production Example]
The desalted herring roe used in the following Examples 1 to 6 and Comparative Examples 1 to 5 was prepared according to the following procedure.
<Preparation of sterilized herring eggs>
Sodium chlorite was added to the salt water to prepare a "saline solution containing disinfectant" with the same concentration of 500 ppm. Salted herring roe was immersed in about three times its weight of the above "saline solution containing disinfectant" for 72 hours to obtain "sterilized herring roe."
<Preparation of desalted herring eggs>
Next, the "sterilized herring eggs" were immersed in approximately three times the amount of salt water for 24 hours to obtain "salted herring eggs." During this treatment period, the salt water was replaced every three hours.
The amount of chlorite ions remaining in the "de-salted herring roe" thus obtained was measured by ion chromatography (with an electric conductivity detector) and found to be below the detection limit (5 mg/kg). A portion of the "de-salted herring roe" was ground up, and the pH of the juice was measured with a pH meter, which gave it a value of 6.6. For reference, when the de-salted herring roe was tasted, it had the texture characteristic of herring roe, but had a strong chlorine smell (Table 1, Reference Example).

[Example 1]
Isomerized sugar, sorbitol, salt, dried bonito extract, and other ingredients were added to water to prepare seasoning stock solution A. The pH of seasoning stock solution A was 6.1.
Lactic acid was added to the above seasoning stock solution A to prepare a seasoning solution having a pH of 3.9.
100 parts by mass of desalted herring roe was immersed in 60 parts by mass of the seasoning liquid. The pH of the immersion liquid (supernatant of the seasoning liquid) was measured every 12 hours after the start of immersion, and it was confirmed that the pH reached equilibrium at pH 5.4 after about 48 hours. The immersion was continued for 72 hours to obtain seasoned herring roe.
Next, the pH of the seasoning liquid and the pH of the seasoned herring roe after soaking were measured. At the same time, the seasoned herring roe was visually observed for the presence or absence of whitening on the surface, and the chlorine odor and texture were ranked as follows by sensory evaluation.
<Chlorine odor>
×: Chlorine odor is present. ◯: A slight chlorine odor is detected, but it is at an acceptable level.
◎: No chlorine smell.
<Texture>
The texture (chewiness) of herring roe was evaluated in comparison with the texture of desalted herring roe before soaking in the seasoning liquid.
×: Harder than unsalted herring roe. The unique crunchy texture of herring roe is gone.
○: Slightly harder than unsalted herring roe, but within the acceptable range.
◎: The texture is the same as unsalted herring roe.
The results are shown in Table 1.

[Example 2]
The same test was carried out as in Example 1, except that the amount of lactic acid added to the seasoning stock solution A was changed and the seasoning solution pH was set to 4.6. After soaking, the pH of the seasoning solution and the pH of the seasoned herring roe were measured, and the quality of the seasoned herring roe was evaluated. The results are shown in Table 1.

[Comparative Example 1]
The test was carried out in the same manner as in Example 1, except that seasoning stock solution A was used as the seasoning liquid as it was, and the pH of the seasoning liquid and the seasoned herring roe after soaking were measured, and the quality of the seasoned herring roe was evaluated. The results are shown in Table 1.

[Comparative Example 2]
The same test was carried out as in Example 1, except that the amount of lactic acid added to the seasoning stock solution A was changed and the seasoning solution pH was set to 3.6. After soaking, the pH of the seasoning solution and the pH of the seasoned herring roe were measured, and the quality of the seasoned herring roe was evaluated. The results are shown in Table 1.

[Example 3]
The test was carried out in the same manner as in Example 1, except that the seasoning liquid was 50 parts by mass, and the pH of the seasoning liquid and the seasoned herring roe after soaking were measured, and the quality of the seasoned herring roe was evaluated. The results are shown in Table 1.

[Example 4]
The test was carried out in the same manner as in Example 1, except that the seasoning liquid was used at 70 parts by mass, and the pH of the seasoning liquid and the seasoned herring roe after soaking were measured, and the quality of the seasoned herring roe was evaluated. The results are shown in Table 1.

[Comparative Example 3]
The same test was carried out as in Example 1, except that sodium lactate was used instead of lactic acid, and the pH of the seasoning liquid, the pH of the seasoning liquid after soaking, and the pH of the seasoned herring roe were measured, and the quality of the seasoned herring roe was evaluated. The results are shown in Table 1.

[Example 5]
The same test was carried out as in Example 2, except that yuzu juice was used instead of lactic acid to set the seasoning solution pH to 4.6. After soaking, the pH of the seasoning solution and the pH of the seasoned herring roe were measured, and the quality of the seasoned herring roe was evaluated. The results are shown in Table 2.

[Comparative Example 4]
The same test was carried out as in Example 5, except that the amount of yuzu juice was changed and the seasoning solution pH was set to 3.6. After soaking, the pH of the seasoning solution and the pH of the seasoned herring roe were measured, and the quality of the seasoned herring roe was evaluated. The results are shown in Table 2.

[Example 6]
The same test was carried out as in Example 2, except that brewed vinegar was used instead of lactic acid and the seasoning solution pH was set to 4.6. After soaking, the pH of the seasoning solution and the pH of the seasoned herring roe were measured, and the quality of the seasoned herring roe was evaluated. The results are shown in Table 2.

[Comparative Example 5]
The same test was carried out as in Example 6, except that the amount of brewed vinegar was changed and the seasoning liquid pH was set to 3.6. After soaking, the pH of the seasoning liquid and the pH of the seasoned herring roe were measured, and the quality of the seasoned herring roe was evaluated. The results are shown in Table 2.

[Example 7]
In the preparation of desalted herring roe in the manufacturing example, an appropriate amount of lactic acid was added to the salt water to adjust the salt water to pH 4.2, but the same procedure was used to obtain desalted herring roe. The obtained desalted herring roe was not whitened and maintained the texture of herring roe. The desalted herring roe was immersed in the seasoning stock solution A used in Comparative Example 1 for 72 hours to obtain seasoned herring roe. The seasoned herring roe had no chlorine odor and had a good taste and texture.

Claims (2)

(a) sterilizing the salted herring eggs with sodium chlorite to obtain sterilized herring eggs;
b) a step of draining the sterilized herring roe that has been subjected to the step a), washing and desalting it with salt water to obtain desalted herring roe;
The method for producing seasoned herring roe includes a step of immersing the desalted herring roe that has been subjected to steps c) and b) in a seasoning liquid containing an organic acid and having a pH of 3.9 or more and 4.6 or less, and adjusting the pH of the seasoned herring roe after immersion to 5.3 or more and 6.0 or less, thereby reducing the residual chlorine odor of the seasoned herring roe finally obtained . 2. The seasoning liquid having a pH of 3.9 to 4.6 used for reducing the residual chlorine odor of sodium chlorite-sterilized herring eggs according to claim 1.