JP4417076B2 - Degeneration-inhibited incubation eggs, packed incubation eggs, methods for producing oden incubation eggs, and storage methods for incubation eggs - Google Patents

Description

  The present invention relates to a degeneration-inhibited incubation egg, a packed incubation egg, a method for producing an incubation egg for oden, and a method for storing the incubation egg.

“Oden” is a representative of Japanese food culture. Speaking of “oden”, the most popular ingredient is said to be eggs.
However, since the egg used in oden is kept in the sauce of oden for a long time, the egg white hardens or the egg yolk emits a sulfur odor, resulting in a significant loss of commercial value. In general, protein loses its original function because the higher-order structure is easily broken and solidified by heating. This phenomenon is collectively referred to as protein denaturation. Many foods use this phenomenon.

  Normally, the pH of egg white is 7.6 to 7.9 immediately after egg laying, but when stored for a long time at room temperature, the pH of the egg is said to rise to reach a maximum value of 9.7. To rise. In the case of producing eggs, if the boil temperature is 99 ° C., the center temperature reaches 92 to 93 ° C. about 20 minutes after the start of boil, and the center temperature of the egg immediately after heating reaches around 90 ° C. In terms of quality, the egg white becomes fragile as the heating time increases.

As a method for suppressing changes in physical properties of eggs that have been caused by heating, there has been (1) an egg white hardening prevention method that uses an acid seasoning to prevent the egg white in egg processed foods from hardening over time (Patent Literature). 1). That is, it consists of a method of immersing eggs with trehalose or / and sucrose aqueous solution with shelled shells, and hardening of egg white can be prevented by pre-treating raw eggs with shell shells with these sugars. is there.
(2) In addition, there is a method for producing an egg processed food that is cooked and processed after adding transglutaminase to the egg (see Patent Document 2). As a result, it is possible to obtain a processed egg food that has a soft and smooth texture and a high degree of juiciness even after cooking and heating, even if it is a high moisture food.
(3) In addition, processed frozen eggs that contain phosphate and are frozen and whose egg white portion hardness is closer to that of freshly boiled eggs even after thawing have been developed ( (See Patent Document 3).
(4) In addition, an antigelling agent for frozen eggs has been developed that uses cyclofractane and / or trehalose as an active ingredient, hardly gels after thawing, does not add taste, and keeps the surface of egg yolk shiny. (See Patent Document 4).

JP-A-7-327639 JP 7-250651 A JP-A-7-135926 JP 7-23703

However, the prior arts shown in Patent Documents 1 and 2 are not effective in preventing freezing denaturation. The prior art shown in Patent Document 3 has a problem that phosphate is used as an additive. In the prior art shown in Patent Document 4, since an anti-gelling agent is added in the state of a raw egg, there is a problem that the shape of the egg is broken and it is not suitable for an egg for oden. Thus, in the prior art, the quality improvement of frozen oden eggs was insufficient.
The present invention has been made paying attention to such problems, and without using phosphate, a denaturation-inhibited incubation egg that can prevent freezing and heat denaturation of an oden egg, a packed egg, and an oden egg It aims at providing the manufacturing method and the preservation method of an incubation egg.

To achieve the above object, the denaturation-inhibited incubation according to the present invention is applied to a pH 7.0 to 10.0 solution containing trehalose having a concentration of 1 to 30% by mass and sodium chloride having a concentration of 0.3 to 1.0% by mass. It is characterized by immersing the shelled eggs and sterilizing them by heating .
The solution may further contain at least one of sucrose (sugar) and maltitol . ( Hereinafter, “mass%” is abbreviated as “%” .)

It is preferable that the solution further contains one or more selected from glycine, sodium acetate, glucono delta lactone, sodium gluconate and potassium carbonate.
The denaturation-inhibiting incubation according to the present invention may be frozen.

The packed eggs according to the present invention are obtained by immersing the shelled eggs in a solution of pH 7.0 to 10.0 containing trehalose having a concentration of 1 to 30% by mass and sodium chloride having a concentration of 0.3 to 1.0% by mass. , Packed and heat sterilized .
The method for producing oden eggs according to the present invention is a shelled egg in a solution of pH 7.0 to 10.0 containing trehalose at a concentration of 1 to 30% by mass and sodium chloride at a concentration of 0.3 to 1.0% by mass. immersing the atmospheric pressure, is impregnated solution into茹卵in vacuum or under reduced pressure, it characterized that you heat sterilization.
The method for preserving an incubation egg according to the present invention immerses the shelled egg in a solution of pH 7.0 to 10.0 containing trehalose at a concentration of 1 to 30% by mass and sodium chloride at a concentration of 0.3 to 1.0% by mass. And heat sterilization .

In the present invention, the sodium chloride may be a sodium salt or a potassium salt. Moreover, salt may be contained in seasonings, such as soy sauce. The eggs used in the present invention are preferably chicken eggs, but may be goose, quail or other eggs. The solution is preferably maintained at pH 7.0 to 10.0 with sodium carbonate or other alkaline agent. The solution is a solution mainly composed of water. The impregnation into the solution is preferably performed under reduced pressure conditions in order to increase the permeability, but may be performed at normal pressure. In the present invention, it is preferable to sterilize by heat after packing.
The denaturation-inhibited incubation egg according to the present invention is particularly suitable as an egg for oden, but it may be used as a seasoned egg or other cooking ingredients.

  The inventors of the present invention have a method for producing eggs that have freezing resistance and heat resistance, relieve the characteristics of eggs, in particular, the disadvantage of being hardened by heating for a long time, and are soft and well melted in the mouth. In addition to the investigation, we examined a method for producing oden eggs that can maintain good quality even in chilled circulation (10 ° C) and a preparation that can improve the storage stability.

  It is clear that the egg white is cured when the eggs are heated in the oden sauce solution. As a result of investigating the influence of saccharides as a method of inhibiting the phenomenon of hardening of egg white (see Table 1), the effect of inhibiting the hardening of egg white after heat treatment of saccharides is in the order of trehalose> sucrose> maltitol> maltose> sorbitol> glucose It was confirmed that. This result indicates that trehalose, sucrose, and maltitol, which are not reducing, have an effect of inhibiting the hardening of egg white. Even in products stored at room temperature for 2 months, the addition of trehalose clearly suppresses the hardening of the eggs.

Usually, when various saccharides are used in food, the way of soaking the taste differs depending on the permeability of the sugar. That is, although it depends on the molecular weight of the sugar, the smaller the molecular weight, the more likely it will penetrate.
In the case of improving the texture of the eggs, egg white hardening (protein denaturation) occurs by repeated heat sterilization and long-term storage in oden sauce. As a result of various studies as a suppression method, it was confirmed that saccharides are effective. In particular, it was confirmed that trehalose has an effect of inhibiting the curing of the eggs.

  Furthermore, the effect when stored frozen was also examined. In order to see the relationship between the trehalose concentration and the improvement in freezing tolerance, the egg white was immersed in a pretreatment solution containing trehalose before freezing, and the effect of preventing the egg white from being frozen was examined (see Table 2). As a result, it was possible to improve the freezing resistance of egg white when the trehalose concentration in the immersion liquid was 10 to 30%. Among these, the trehalose 30% solution was able to significantly improve the freezing tolerance. The amount of trehalose penetrating into the egg white at that time was calculated to be 15.7%.

  Further, in the case of storing the eggs in a frozen state, it was considered that the influence of the pH of the immersion liquid used for the pretreatment of the eggs was large and examined (see Table 3). As a result, when the pH of the pretreatment immersion liquid was in the range of 8.8 to 9.4, slight egg white damage was observed in the sensory evaluation at 9.1, but when the pH was around 9.4, the most preferable result was obtained. all right.

  When freezing resistance is imparted by the dipping method, the freezing resistance of egg white improves when infiltrated under vacuum or reduced pressure conditions. Furthermore, when it hold | maintains in immersion liquid and it freezes, the inhibitory effect of freezing tolerance becomes high. From the above, trehalose is effective in suppressing the heat denaturation and freezing denaturation of egg whites of eggs, and considering the relationship with pH, it is more effective by adjusting the pH to 7 or more, preferably pH 7.0 to 10.0. It was confirmed that it was enhanced.

  Moreover, when the influence of salt was examined, it turned out that frost resistance improves by adding salt as a relationship between the salt concentration in the immersion liquid used for a pretreatment liquid, and frost resistance (refer Table 4). ). In the present invention, there was a tendency to improve the egg white state at a salt concentration of 1.0% or less, and in particular, there was a tendency to significantly improve the egg white state at 0.3%. However, when the salt concentration was excessively added, the adverse effect was obtained, and when the salt concentration was 0.7%, the egg white state tended to be worse than when 0.3% was added. This tendency is thought to be due to the dehydration phenomenon of the egg because the osmotic pressure in the solution increases by adding salt. That is, it is considered that under high osmotic pressure, trehalose was inhibited from penetrating into the incubation.

In addition, assuming an actual distribution system, examination was also made on conditions under which the deterioration due to heating is small, the frost resistance is excellent, and the preservability is excellent in the chilled (10 ° C.) distribution.
In the case of oden sauce, the soy sauce-based seasoning is usually weakly acidic with a pH of about 4.5 to 5.0. Under this condition, it is predicted that the egg white will harden when the eggs are immersed for a long time. In order to suppress this, the inventors examined the substances that are generally considered to have an effect of suppressing protein gelation, such as sugars, sugar alcohols, fats and oils, peptides, organic acids, and emulsifiers. As a result, it was confirmed that the saccharide has an effect of inhibiting egg white hardening. Among them, it was confirmed that trehalose improves the freezing resistance of eggs compared to other saccharides, and it was also found that egg white hardening was suppressed even after prolonged heating. The curing inhibitory effect varies significantly depending on the amount of trehalose used, pH, and ionic strength (presence of salt). This effect is believed to vary with egg type, egg freshness, moisture, freezing and thawing temperature, time, thawing storage temperature and duration. As a result of examining the factors that suppress the hardening of egg whites, it has become possible to supply "oden eggs" that are soft and melt well in the mouth.

  On the other hand, in order to enable chilled distribution under the condition of 10 ° C., it is necessary to examine the bacteriostatic bacteriostatic method and its suppression method. In order to establish this technology, we focused on organic acids. As a result, the storage stability could be improved by the combination of sodium acetate, sodium gluconate, and glucono delta lactones. Furthermore, since it is known that sodium gluconate has a protein denaturation inhibitory effect, it is predicted that even after long-term refrigeration after the incubation of eggs, it is possible to suppress the loss of texture.

  Usually, when a heated egg is stored for a long period of time, a sulfur odor may be generated. As a result of various studies on the suppression method, it was confirmed that the combined use of sodium acetate and sodium gluconate reduced unpleasant sulfur odor and had a masking effect.

  Furthermore, since the taste of egg white is deteriorated by long-term storage, this suppression method was examined. As a method for this, it was considered necessary to increase the buffering capacity of the immersion liquid of the incubation eggs, and whether or not it was possible to cope by adding organic acids was examined. As an organic acid to be used, glucono delta lactone with good acidity and acid odor was adopted. Gluconodelta lactone is hydrolyzed to yield gluconic acid. Gluconic acid does not smell because it is odorless, its acidity is milder than other organic acids, and its taste is less affected. Gluconic acid has a plurality of —OH groups, which are functional groups that are auxiliary taste groups, and therefore has an effect of gathering tastes, and it is possible to minimize the influence of other additives on taste.

  As described above, it is possible to improve the texture by increasing the water-holding power by making the pH of the incubation eggs alkaline, and the texture can be improved by adjusting the pH of the immersion liquid and strengthening the buffering power. On the other hand, if the alkalinity is high, when the egg is heated, undesired phenomena such as blackening of egg yolk and enhancement of sulfur odor may occur. Eggs have higher pH and stronger buffer than other foods, so it is difficult to adjust pH directly. Therefore, by adjusting the pH to 8.0 with potassium carbonate and utilizing the buffering ability of sodium gluconate and glucono delta lactone, it becomes possible to maintain the pH and balance of the egg.

  In particular, glucono delta lactone is characterized by being gradually hydrolyzed and lowered in pH when dissolved in water and heated, so that the buffering power can be further strengthened. Glycine improves storability due to bacteriostatic gram-positive bacteria, and sodium acetate improves storability due to bacteriostatic gram-negative bacteria. That is, by using these two additives having a high bacteriostatic effect, a synergistic effect is expected against these spoilage bacteria. Furthermore, gluconic acid is expected to have an additive synergistic effect because it has a bacteriostatic effect comparable to that of acetic acid in the pH range of a normal seasoning liquid.

  According to the present invention, there are provided a denaturation-inhibited incubation egg that can prevent freezing denaturation and heat denaturation of oden eggs without using a phosphate salt, a packed egg, a production method of oden incubation, and a preservation method of the incubation egg. Can do.

Experimental example 1

[Effects of various sugars on curing]
Chicken eggs (200 g) were boiled at 90 ° C. for 16 minutes, cooled in running water, and slowly shelled to produce eggs. Thereafter, the eggs were immersed in the seasoning liquid for 2 hours, drained, filled into a pack, and retorted (115 ° C .: 20 minutes). The effects of various sugars were examined on the eggs thus prepared. The concentration of various sugars was set to 20 to 22%, and the Bx of the seasoning liquid was set to the range of 24.4 to 24.6. Incubation hardness was evaluated by rheometer measurement and sensory evaluation, and was performed on products immediately after retort and stored at room temperature (2 months). The seasoning liquid standard prescription was sugar: 40 g, water: 138 g, soy sauce: 20 g, and salt: 2 g. The experimental results are shown in Table 1.
From Experimental Example 1, it was confirmed that the effect of inhibiting the hardening of egg white after heat treatment of sugars was in the order of trehalose>sucrose>maltitol>maltose>sorbitol> glucose.

Experimental example 2

[Relationship between trehalose concentration and freezing tolerance]
Eggs were produced by heating the eggs in a boil tank at 90 ° C. for 16 minutes. This egg (300 g) is packed and packaged together with 250 g of a treatment solution formulated with trehalose in the range of 1% to 30% and adjusted to pH 9.5 with sodium carbonate. For 24 hours. Thereafter, it was frozen at −20 ° C., and the products on day 36 and day 63 after frozen storage were evaluated. As evaluation, the frozen sample was thawed with running water, and then Bx measurement of the solution, egg weight measurement, and taste evaluation (appearance, yolk, white) were performed. The evaluation method was performed by tasting seven monitors.
The immersion liquid standard formulation was trehalose: 27.8 to 83.3 g, sodium carbonate: 0.24 g, water: 166.4 to 221.9 g, Bx: 10.0 to 31.0, measured pH: 10.6. The experimental results are shown in Table 2.
According to Experimental Example 2, it seemed that there was not much change in the freezing tolerance of egg white when the trehalose concentration in the immersion liquid was 10 to 20%, but it was possible to improve the freezing tolerance in the 30% trehalose solution. It could be confirmed. If it is less than 1%, the freezing resistance is insufficient. Conversely, if it exceeds 30%, it is not preferable in terms of freezing resistance.

Experimental example 3

[Influence of pH of immersion liquid]
Incubated eggs were filled in a pack together with the immersion liquid, vacuum impregnation (−500 mmHg, 2 hours) was performed, and heat sterilization (80 ° C., 30 minutes) was performed. Thereafter, it was cooled, and after 24 hours of infiltration, it was stored frozen at -20 ° C., and quality evaluation was performed 36 days after frozen storage and 63 days later.
The evaluation was performed by thawing the frozen product with running water and then evaluating the Bx of the immersion solution, the weight of the egg, and the taste evaluation (appearance, yolk, white) in six stages, and the total of the average values. Sodium carbonate was used as a pH adjuster for the immersion solution.
The pH of the immersion liquid was set in the range of 9.0 to 10.0. Furthermore, the amount of trehalose permeation was measured.
The standard prescriptions for the immersion liquid were trehalose: 55.6 g, water: 194.0 to 194.6 g, and sodium carbonate: 0.12 to 0.4 g. The experimental results are shown in Table 3.
According to Experiment 3, in the range of pH of the pretreatment immersion liquid from 8.8 to 9.4, some egg white damage was observed in the sensory evaluation at 9.1, but the most preferable result is obtained when the pH is around 9.4. I understood it.

Experimental Example 4

[About the effect of salt concentration]
Raw eggs were heated in a boil tank at 90 ° C. for 16 minutes to produce eggs. This incubated egg (300 g) was added to the package with 250 g of a treatment solution adjusted to pH 9.5 with sodium carbonate by adding sodium chloride in a range of 0 to 0.7% with a trehalose concentration of 20%, and heat sterilization (80 ° C., 30 Minutes) and then cooled and subjected to infiltration treatment at room temperature for 24 hours. Vacuum permeation treatment conditions were employed as the permeation treatment conditions. Thereafter, a freezing treatment was performed at −20 ° C. Evaluation was carried out on products on day 36 and day 63 after frozen storage.
As evaluation, after thawing a frozen sample under running water, measurement of Bx of the solution, measurement of egg weight, and taste evaluation (appearance, yolk, white) were performed. The experimental results are shown in Table 4.
Experiment 4 confirmed that the egg white state was poor at a salt concentration of 0.7%, and that the egg white state was significantly improved at a salt concentration of 0.3%.

The eggs were filled into the pack together with the immersion liquid, vacuum impregnated (−500 mmHg, 24 hours), and heat sterilized (80 ° C., 30 minutes). Thereafter, the mixture was cooled and infiltrated for 24 hours, and stored frozen at -20 ° C.
This sample was frozen and thawed on a daily basis (1 day, 30 days, 63 days), then immersed in oden solution, and the hardness, texture, and taste of the eggs were evaluated by a five-point scoring method. The standard prescription of the outer immersion liquid was trehalose: 55.6 g, water: 194.0 g, sodium carbonate: 0.4 g, pH: 9.4, Bx: 25.0. The results are shown in Table 5.

  As shown in Table 5, when the eggs are not pre-immersed, the egg white and egg yolk are markedly denatured by freezing, the physical properties of the egg white and egg yolk are fragile, the water separation is severely reduced, and the taste is also significant. Declined. On the other hand, when the immersion treatment of the present embodiment is performed on the eggs, even if the freezing treatment is performed, protein modification of egg white and egg yolk, its physical properties, decrease in water separation, and decrease in taste are considerably suppressed.

表６に示すように、本実施例の茹卵は、日持ち向上試験結果が従来品に比べ
て良好であった。 In order to examine the preservation method of the eggs when immersed in the oden dashi, the eggs were heated in a boil tank at 90 ° C. for 16 minutes to produce the eggs. Thereafter, oden broth, incubation, and a dipping solution for improving shelf life were packed in a pack. The formulation of the immersion liquid was 43% glycine, 16% sodium gluconate, 13% sodium acetate, 10% potassium carbonate, 10% gluconodeltalactone, and 8% trehalose. The packed product was heated at 85 ° C. for 30 minutes. After cooling, a part thereof was stored at 10 ° C. A shelf life improvement test was performed on the sample immediately after cooling and the sample on the fifth day after storage, and the breaking strength was measured. In addition, the egg quality was evaluated by sensory test. Table 6 shows the result of comparison with the conventional product.

As shown in Table 6, the incubation results of the present example showed better results in the shelf life improvement test than the conventional products.

Claims (7)

It is characterized by immersing the shelled eggs in a solution of pH 7.0 to 10.0 containing trehalose at a concentration of 1 to 30% by mass and sodium chloride at a concentration of 0.3 to 1.0% by mass and sterilizing by heating. Degeneration-inhibited incubation eggs. The solution further sucrose and maltitol inhibiting denaturation茹卵according to claim 1, characterized in that it comprises at least one. The denaturation-inhibited incubation according to claim 1 or 2 , wherein the solution further contains one or more selected from glycine, sodium acetate, glucono delta lactone, sodium gluconate and potassium carbonate. The denaturation-inhibited incubation according to any one of claims 1 to 3 , which is frozen. The shelled eggs are immersed , packed and heat-sterilized in a solution of pH 7.0 to 10.0 containing trehalose at a concentration of 1 to 30% by mass and sodium chloride at a concentration of 0.3 to 1.0% by mass. Packed eggs characterized by that. The shelled eggs are immersed in a solution of pH 7.0 to 10.0 containing trehalose at a concentration of 1 to 30% by mass and sodium chloride at a concentration of 0.3 to 1.0% by mass, and are subjected to normal pressure, vacuum or reduced pressure conditions. in solution to impregnate the茹卵a method of oden for茹卵characterized that you heat sterilization. The shelled eggs are immersed in a solution of pH 7.0 to 10.0 containing trehalose at a concentration of 1 to 30% by mass and sodium chloride at a concentration of 0.3 to 1.0% by mass , and sterilized by heating. How to preserve eggs.