JP3529734B2 - How to keep eggs fresh - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for maintaining freshness of eggs.

[0002]

2. Description of the Related Art Eggs have a high nutritional value and a low price, which is said to be a complete food, and they are produced in large quantities at about 48 million tons per year in the world and about 2520,000 tons per year in Japan. It has been considered as a more important food than before. Especially in Japan, it is widely used for raw food and processing.

[0003] However, the quality of eggs may deteriorate during storage, and the thickened egg white inside may become water-like, the height of egg yolk may be reduced, and spoilage due to microbial contamination through the eggshell may be observed.

In order to prevent the freshness of eggs from decreasing during storage,
The refrigeration method has been widely used from the past. In addition, a method of coating the surface of the egg shell with a natural polymer compound (oil, fat, starch, protein, etc.), a method of putting it in a closed container containing a high concentration of carbon dioxide and keeping it at a low temperature of about 5 ° C, 100 to 200 ppm A method of washing with an aqueous solution of sodium chlorite is known. Since these methods require high safety because they are used for food, at the same time storage, transportation and
Be able to maintain quality in various temperature ranges during distribution,
It is required to be easy to operate because it is processed in large quantities.

[0005]

However, the above method of maintaining freshness is not preferable except for the refrigeration method in terms of safety, response to temperature changes, and complicated operation, and the above three conditions are sufficiently satisfied. The one to meet was unknown. The present invention has been made in view of the above prior art, and an object of the present invention is to provide a method of maintaining freshness of eggs, which is highly safe, can be applied in various environmental temperature ranges, and is easy to operate.

[0006]

In view of the above problems, as a result of intensive studies by the present inventor, it was found that a method for maintaining freshness of eggs by heat treatment satisfies the above conditions and exhibits an excellent effect in maintaining freshness. The invention was completed.

[0007] The subject of the present invention is, therefore, a method for maintaining the freshness of an egg, which comprises immersing the egg in warm water at 50 ° C for 10 to 20 minutes and air-drying it. Moreover, the said method can also be dry-heat-processed, and especially it is 3-5 in the place of 50 degreeC.
It is preferable to use a method of storing for a time. In the above method, it is preferable to perform the treatment within 7 days after refrigeration and after refrigeration. The method can be used most often in chicken eggs.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will be described below. The effect of the hot water immersion treatment, which is the first method of heat treatment, differs depending on the temperature of the hot water used and the immersion time. The lower the temperature of the hot water, the longer the time, and the higher the temperature of the hot water, the shorter the time.

The range of temperature and soaking time applicable to this condition depends on the size of the egg, but a particularly preferred condition is 50 ° C.
The treatment is performed for 0 to 20 minutes, and if the temperature is lower than 45 ° C, the effect of the present invention is not sufficiently exhibited, and if the temperature is 55 ° C or higher, the eggs are heat-denatured.

The dry heat treatment, which is the second method of heat treatment, depends on the size of the egg, but a particularly preferable condition is 50 ° C. for 3 to 5 hours. When the temperature is lower than 45 ° C,
The effect of the present invention is not sufficiently exhibited, and if the temperature is 55 ° C. or higher, the eggs will be heat-denatured. Even when dry heat treatment is performed, the same effect as hot water immersion treatment is observed.

It is desirable that eggs are fresh at all stages of distribution, sale, processing and consumption. Since the freshness of eggs decreases with each passing of days after spawning, it is preferable that the hot water immersion treatment of the present invention is performed as soon as possible after spawning. In particular, it is extremely effective to carry out within 7 days when refrigerated, and within 2 days when kept at room temperature. If the treatment is performed within this period, a fresher state will be maintained. The freshness preservation method of the present invention can be applied to all edible eggs such as chicken eggs, quail eggs, and duck eggs, but it is considered that chicken eggs are most frequently used.

[0012]

EXAMPLES Next, the present invention will be described in more detail by way of examples, but the technical scope of the present invention is not limited by these examples.

Prior to the examples, the evaluation criteria of the freshness retention effect of the present invention will be described. Here, the freshness of an egg is shown by using the how unit (HU) that is generally most often used as the freshness index value.

1 ^{U = 100log (H-1.7W 0.37} +7.6) ... (1) [ wherein, H is the concentrated egg whites height (mm), W represents the weight of the egg (g). ]

According to the American standard, the evaluation AA: H. U value is 72 or more. Evaluation A: H.I. U value is 55 or more and less than 72. Evaluation B: H.I. U value is 32 or more and less than 55. Evaluation C: H.I. U value is less than 32. Has become. Eggs suitable for raw eating are generally rated AA
And the evaluation A, the evaluation AA and the evaluation A were defined as fresh eggs, and the evaluations B and C were defined as the eggs with deteriorated quality. In addition, visual evaluation was added as a sensory test.

[0015]Treatment conditions (warm water temperature / immersion time) and preservation of freshness
Longevity relationship Next, hot water immersion time and freshness retention effect are tested. Purchase 150 pieces of commercially available egg size M, 6 for each 25 pieces
Divided into groups. 40, 45, 50, 5 eggs in each of the 5 groups
5, 10, 15, 20, 25, 30 in 5, 60 ℃ warm water
After soaking for a minute, it was air dried. One group was untreated. Store treated and untreated eggs in a 20 ° C incubator
Then, after 10 days, take out 5 each, the weight of the concentrated egg white
The H. The U value was calculated. 5 H. U value
On average, with the sensory evaluation of observing the broken egg, the untreated egg
By comparison, the presence or absence of the effect was evaluated based on the following criteria.
The results are shown in Table 1.Evaluation criteria ⊚: A large effect is recognized. ○: The effect is recognized. Δ: The effect is slightly recognized. X: No effect is observed.

[0016]

[Table 1] 5 minutes 10 minutes 15 minutes 20 minutes 25 minutes 30 minutes 40 ° C × × × × × × × 45 ° C × × △ △ ○ ○ 50 ° C × ○ ◎ ◎ ○ △ 55 ° C △ △ × × Not measurable due to heat denaturationNot measurable due to heat denaturation at 60 ℃ As can be seen from Table 1, the freshness-retaining effect is not seen in the 40 ° C treatment.
No effect was observed after treatment at 45 ° C for 15 minutes or longer.
It was At 50 ° C treatment, an effect was observed after 10 minutes or more.
A significant effect was observed at -20 minutes. But after that
The effect tends to decrease over the longer time. 55 ℃ treatment
Then, the effect is recognized in 5 to 10 minutes, but when it is longer than that
The effect disappeared during the period, and heat denaturation occurred for 25 minutes or more. Well
In addition, in the case of 60 ° C treatment, the heat
I had sex From this, the temperature of the hot water used in the present invention is
It is preferable that the treatment time is 45 to 55 ° C. and the treatment time is 5 to 30 minutes.
The optimum temperature for hot water is 50 ° C and the treatment time is 10 to 20 minutes.
It was confirmed that

Next, an effect test method of the freshness preservation method of the present invention
Will be described.Example 1 Freshness retention period at 20 ° C Eggs are not necessarily distributed by the cold chain.
Therefore, the egg treated with the present invention and the egg treated as a comparative example
Compare the freshness retention period at 20 ℃ using Riko
It was Boris brown egg (Mita chicken garden Rikimaru-kun) M size
We bought 80 pieces and divided them into half. One is warm water at 50 ° C
And soak in air for 15 minutes, then air dry and leave the other untreated
It was Store treated and untreated eggs in a 20 ° C incubator
Then, take out two pieces every four days and the height of the thick egg white
Is measured, and H. The U value was calculated and the average value was calculated. That conclusion
The results are shown in FIG.

As can be seen from FIG. 1, the quality of the untreated eggs deteriorated after 24 days, whereas the treated eggs could retain their freshness for 56 days. From this, the treated egg of the present invention has a freshness retention period of 20 ° C. of 2 times as compared with the untreated egg.
It was recognized that it could be extended more than twice.

[0019]Example 2 Freshness retention period at 4 ° C Assuming that eggs are stored in the refrigerator, treated eggs and untreated
The freshness retention period at 4 ° C. was compared using the eggs. Boris brown egg (Mita chicken garden Rikimaru-kun) M size
We bought 80 pieces and divided them into half. One is warm water at 50 ° C
And soak in air for 15 minutes, then air dry and leave the other untreated
It was Store treated and untreated eggs in a 4 ° C incubator
However, every 2 weeks, 2 each take out weight, height of thick egg white
Is measured, and H. The U value was calculated and the average value was calculated. That conclusion
The results are shown in FIG.

As can be seen from FIG. 2, the freshness of both treated and untreated eggs was maintained at 26 weeks, but the H. The U value was 78 for treated eggs, compared to 64 for untreated eggs. From this, it was confirmed that the treated egg of the present invention had a better freshness-retaining state at 4 ° C than the untreated egg.

[0021]Example 3 Maintaining freshness at 4 ° C. → 20 ° C.
period Assuming that refrigerated eggs are distributed at room temperature, no processed eggs
When treated eggs are stored at 4 ° C and then at 20 ° C
The freshness retention period in was compared. Boris brown egg (Mita chicken garden Rikimaru-kun) M size
I bought 40 pieces and divided them in half. One is warm water at 50 ° C
And soak in air for 15 minutes, then air dry and leave the other untreated
It was Treated and untreated eggs in an incubator at 4 ° C for 4 weeks
Stored. After that, transfer to an incubator at 20 ° C for storage,
Take out two of them each week and adjust the height of the concentrated egg whites.
Measured, H. The U value was calculated and the average value was calculated. as a result
Is shown in FIG.

As can be seen from FIG. 3, the untreated eggs had a temperature change of 2
The treated eggs were able to retain their freshness for 6 weeks (10 weeks) after the temperature change, as compared with the deterioration in quality for 6 weeks (6 weeks).
From this, it was confirmed that the treatment of the present invention can maintain the freshness-retaining effect even if the storage temperature fluctuates.

[0023]Example 4 Freshness retention in three types of eggs
Comparison of effects Egg quality varies depending on chicken breed / age, season, feed, etc.
Can be seen. Therefore, it is expected that there will be differences in freshness retention
It is possible to do so, using the following 3 types of eggs, treated and untreated eggs
The freshness retention period was compared with. Commercial item A: Rikimaru-kun M size (Sanda chicken garden) Commercial item B: Eggs sent directly from the farm, M size (Ito-Yokado) Commercial product C: Egg of the forest M size (Ise food) 60 eggs each of the above three kinds were purchased and divided into half.
One is soaked in warm water at 50 ° C for 15 minutes and then air dried.
The other side was untreated. Store treated and untreated eggs in an incubator at 25 ℃
Then, take out two pieces every four days and the height of the thick egg white
Is measured, and H. The U value was calculated and the average value was calculated. That conclusion
The results are shown in FIG.

In the case of the commercial product A, the quality of untreated eggs was deteriorated in 20 days, whereas the treated eggs could keep their freshness for 48 days. In the case of the commercial product B, the quality of the untreated eggs deteriorated in 16 days, while the freshness of the treated eggs could be maintained for 48 days. In the case of the commercial product C, the quality of the untreated eggs deteriorated after 8 days, whereas the treated eggs showed H. U value of 70 and high freshness could be maintained.
From this, the untreated eggs showed a difference in the freshness retention period depending on the type of egg, but it was clearly recognized that the freshness retention period could be extended to any type of egg by the treatment of the present invention. .

[0025]

As described above, according to the heat treatment of the present invention, it is possible to obtain a method of maintaining the freshness of eggs, which is highly safe, can be applied in various storage temperature ranges, and is easy to operate.

[Brief description of drawings]

FIG. 1 shows that the treated eggs of the present invention and the untreated eggs of H. It is a change in the U value.

FIG. 2 shows the treated eggs of the present invention and the untreated eggs at a storage temperature of 4 ° C. It is a change in the U value.

FIG. 3 shows that the treated and untreated eggs of the present invention were stored at 4 ° C. for 4 weeks and then stored at 20 ° C. It is a change in the U value.

FIG. 4 shows the H. esculentum of the treated and untreated eggs of the present invention using three types of commercial products at a storage temperature of 25 ° C. It is a change in the U value.

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Nagao Ogura 1-26 Sukedo-cho, Ashikaga City, Tochigi Prefecture Kazami Co., Ltd. (72) Inventor Yasushi Hongo 8-17-16 Minamibayashi, Yamato-shi, Kanagawa Prefecture (72) Inventor Kurara Masakuni, 4-18-8 Tsubakiyama, Hasuda City, Saitama Prefecture (56) Reference JP-A-11-290029 (JP, A) JP-A-59-14746 (JP, A) JP-A-9-504944 (JP, A) ( 58) Fields investigated (Int.Cl. ⁷ , DB name) A23B 4/00-5/06

Claims (4)

(57) [Claims] 1. A method for maintaining freshness of an egg, which comprises immersing the egg in warm water at 50 ° C. for 10 to 20 minutes and air-drying it. 2. A method for maintaining the freshness of an egg, which comprises storing the egg at a temperature of 50 ° C. for 3 to 5 hours. 3. A method of maintaining freshness of an egg, which comprises performing the method of maintaining freshness according to claim 1 or 2 within 7 days after spawning and then refrigerating. 4. The egg is a hen's egg.
~ 3 freshness preservation method.