JPH10155415A - Freshness maintaining method for raw egg by gaseous carbon dioxide hermetically sealing package - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain the freshness of raw eggs at a normal temperature over the relatively long period of time by using a humidity control means for eliminating excessive humidity inside a hermetically sealing container in the hermetically sealing container made of a gas barrier enclosing air. SOLUTION: By holding the raw eggs in the hermetically sealing container made of the gas barrier enclosing the gaseous carbon dioxide of a low density (5-30%) capable of maintaining the amount of the gaseous carbon dioxide contained in the eggs at the time of laying the eggs and using the humidity control means (example; desiccant selected from calcium chloride, silica gel or the combination) for eliminating the excessive humidity in the hermetically sealing container, the sufficient freshness is kept over the long period of time of about 14-15 days, dew condensation inside the hermetically sealing container is prevented simultaneously and the generation of microorganisms such as molds or the like is prevented as well.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for maintaining freshness of fresh foods, particularly fresh eggs at room temperature for a relatively long time.

[0002]

2. Description of the Related Art In recent years, consumers have become more and more conscious of foods. In particular, consumers are particularly interested in freshness of fresh foods, presence of additives, and use of agricultural chemicals. The needs for food products, pesticide-free foods, etc. are increasing. Raw chicken eggs are no exception, and quality standards, especially in freshness, are becoming stricter.

[0003] Most of the current poultry farms are generally located in remote areas from the city center, but are usually distributed for a relatively short period of time (2 to 3 days) by modern distribution systems. However, since the above distribution is generally performed at room temperature, the howe unit, which is an index of the freshness of raw chicken eggs, is significantly reduced in a short period of time when the temperature is high in summer. In addition, after being displayed at a retail store, raw chicken eggs that can be finally obtained by consumers are usually about 3 to 6 days after laying eggs, and most of the purchased raw chicken eggs are in each household and It is stored for several days until it is used for cooking at each eating and drinking point.

[0004] In order to satisfy the freshness standard of raw chicken eggs in a high temperature area and / or a high temperature season,
It is necessary to minimize the decline in freshness during the distribution process.

[0005] Feces and the like adhere to the shell surface of raw hen eggs after laying eggs, and are often contaminated by many microorganisms. However, raw chicken eggs have an internal structure in which high-viscosity egg white gel, which has a strong antimicrobial action, has an internal structure that covers the entire periphery of the yolk, which is mechanically supported by a support called Karaza. It protects the yolk, which has low resistance to, from the action of microorganisms and from mechanical shocks. Generally, the egg contents immediately after laying eggs are in a substantially sterile state, and it is difficult for microorganisms to invade from the outside and grow inside the eggs as long as the quality of egg white is maintained.

[0006] The mechanism of the decrease in freshness and decay of raw chicken eggs is considered to be due to the decrease in the quality of the egg white gel, that is, the decrease in viscosity, which causes the yolk to approach or come into contact with the inner wall of the eggshell and to be affected by microorganisms through the eggshell. I have. The decrease in the viscosity of egg white gel is generally caused by the release of carbon dioxide from the egg white gel during storage of raw chicken eggs, resulting in a decrease in the concentration of carbon dioxide in the egg white gel and an increase in the pH value of the egg white gel. It is admitted that.

Therefore, it is understood that suppressing the decrease in the viscosity of the egg white gel, that is, the decrease in the concentration of carbon dioxide in the egg white gel is effective for maintaining the freshness of the raw chicken eggs.

[0008] Although refrigeration and freezing are common means for maintaining freshness of fresh food, performing refrigeration or freezing throughout the distribution process and during the period of display at stores is enormous. Furthermore, the freshness of raw chicken eggs also depends largely on the carbon dioxide concentration (pH) in egg white, as described above, so that refrigeration alone is not sufficient. In addition, in the case of frozen storage, the frozen egg obtained by freezing has high storage properties, but the characteristics of egg white or egg yolk are liable to change, and when the thick egg white gel in raw chicken eggs is thawed and becomes water-like after thawing, the quality deteriorates. It has the disadvantage of saying.

Therefore, in order to maintain the freshness of raw chicken eggs,
The following methods using carbon dioxide have been developed as an alternative to refrigeration or as a method to use in combination with refrigeration.

" Journal of Chemical Indus
Tree 56, 96T-101T (1937; Mr. Molton) "discloses the storability of eggs in a sealed container of carbon dioxide over a period of several months and the effect of carbon dioxide on egg whites during that period. ing. The purpose is to maintain the quality by preventing the growth of microorganisms by sealing and storing in high-concentration carbon dioxide, but conversely, it is not possible to prevent the condensation of eggs in a sealed container and the high concentration of carbon dioxide The quality of the preserved eggs is deteriorated, such as the whitening of the egg white.

[0011] It is generally accepted that the reduction of the Howe unit of eggs can be suppressed by keeping the raw chicken eggs in a carbon dioxide atmosphere, but if the eggs are left in a high-concentration (30% or more) carbon dioxide gas for a long period of time. In addition, adverse effects such as strong white turbidity in the egg white gel of the egg immediately after opening, difficulty in peeling the boiled egg shell, and / or loss of elasticity of the solidified egg white occur.

Japanese Patent Publication No. 55-6340 filed by the present applicant
As a method for solving the above-mentioned problem, Japanese Unexamined Patent Publication (Kokai) No. HEI 9 (1995) discloses a method of solving the above-mentioned problem by placing raw chicken eggs in a gas permeable container before entering a transportation process, and having a concentration of 30 to 60% carbon dioxide at room temperature. Disclosed is a method for maintaining the freshness of raw hen eggs that are exposed temporarily (6 to 24 hours). Further, it is disclosed that in the transportation process, the carbon dioxide atmosphere is maintained by a special vehicle having a storage capable of creating a carbon dioxide atmosphere, such as a fresh fish transport vehicle.

However, the transportation process is a part of the whole distribution process. In practice, since the time spent in the washing factory, the drying warehouse, and one corner of the market is long, it is necessary to distribute the raw fresh eggs. It is necessary to suppress the release of carbon dioxide during these standing periods. Further, in the currently established relay transport system, the transport vehicles frequently change, so it is necessary to reload the loaded raw eggs every time, and accordingly, a large amount of carbon dioxide in the storage of the transport vehicles is replaced. However, such replacement of a large amount of carbon dioxide gas is not preferable in terms of operability, cost, and environmental problems such as global warming.

The " Poultry Farming October Issue (1989, Mr. Nakagawa, Niigata Prefectural Livestock Experiment Station)" has a carbon dioxide gas concentration of about 10% (egg white pH 7.5 to 7.5) during egg formation in the oviducts of chickens.
6) Therefore, it is disclosed that an effective carbon dioxide concentration of 10% when treating chicken eggs with carbon dioxide is a tentative standard, and that raw chicken eggs or raw chicken eggs put in a gas-permeable egg pack are used. Disclosed is a method for maintaining the freshness of raw hen's eggs exposed to carbon dioxide at a concentration of 10 to 30% (practically 20 to 30%) for 12 to 24 hours.

However, the effect of maintaining the freshness by the above-mentioned method is only to such an extent that a decrease in freshness of raw chicken eggs can be delayed by one to two days. Therefore, in order to distribute raw chicken eggs with sufficiently high freshness and to be able to deliver them to consumers, it is necessary to suppress the release of carbon dioxide gas during the distribution process including the above-mentioned leaving period. Furthermore, carbon dioxide treatment is performed by placing raw chicken eggs or a gas-permeable pack containing raw chicken eggs in a large, gas-impermeable plastic container, or by covering them with a highly airtight sheet. When performed under high-temperature and high-humidity conditions, mold and the like may be generated on the eggshell.

Japanese Patent Application Laid-Open No. 7-61481 filed by the present applicant
Japanese Unexamined Patent Publication (Kokai) (published March 7, 1995) has a space filled with carbon dioxide gas manufactured using a carbon dioxide gas permeable material. Good) Carbon dioxide release film or sheet, and raw raw egg comprising packaging the raw egg in the carbon dioxide release film or sheet and keeping the raw egg in a carbon dioxide atmosphere (330 ppm to 60%). A method for maintaining the freshness of chicken eggs is disclosed. Although the above method discloses that a carbon dioxide gas atmosphere can be achieved for a relatively long period (6 days), the concentration actually achieved in the examples is as low as about 800 ppm, and the freshness of the chicken eggs is maintained. Effective carbon dioxide concentration (10
%). Furthermore, the method described in JP-A-7-61481 has the disadvantage that raw chicken eggs need to be packaged using a special film.

A method for maintaining the freshness of food using carbon dioxide gas is also known in fields other than the field of eggs such as confectionery and the like, and this method involves the use of carbon dioxide gas in bags made of a carbon-impermeable film or the like. Store in a sealed container.

However, with regard to raw chicken eggs, the moisture released from the eggshell due to sealing remains in the container and the humidity inside the container increases, and dew condensation easily occurs with a slight change in temperature, thereby visually impairing the commercial value. Not only does it hurt,
It can also cause the generation of microorganisms such as mold and decay. Therefore, it is necessary to preserve raw chicken eggs in a gas-permeable and / or open container. Until now, the above-mentioned preservation technique using a sealed container filled with carbon dioxide gas could not be used for raw chicken eggs.

[0019]

SUMMARY OF THE INVENTION The above-mentioned various drawbacks in the prior art using carbon dioxide for maintaining the freshness of raw hen's eggs are improved, and a comparison is made between the concentrations of carbon dioxide atmospheres effective for maintaining the freshness of the raw hen's eggs. At the same time, it is possible to maintain the freshness of raw chicken eggs at room temperature for a relatively long period of time by preventing condensation in the container that causes the generation of microorganisms such as mold and rot, etc. An inexpensive and simple method for maintaining freshness is provided.

[0020]

SUMMARY OF THE INVENTION The present invention provides a gas barrier (substantially 5 to 30%) containing carbon dioxide at a low concentration (about 5 to 30%) enough to maintain the amount of carbon dioxide contained in eggs during laying eggs. By holding the raw chicken eggs in a gas-impermeable sealed container and providing the container with humidity control means for removing excess humidity, the freshness can be reduced over a long period of about 14 to 15 days. To prevent fresh chicken eggs from being taken out of the container and maintain freshness enough to maintain the egg white gel in the state at the time of laying eggs, and at the same time, prevent dew condensation in the sealed container to prevent mold, etc. The present invention relates to a method for maintaining the freshness of raw chicken eggs, which also makes it possible to prevent the generation of microorganisms.

The method for maintaining fresh hen's egg freshness of the present invention makes it possible to store raw hen's egg in a sealed container, which has been impossible in the past, and thereby the effectiveness of the effect of carbon dioxide gas on maintaining fresh hen's egg freshness. And enable long-term storage of raw chicken eggs at room temperature for the first time.

Since carbon dioxide gas is naturally generated from the raw chicken eggshell during storage, simply storing the raw chicken eggs in a gas-barrier sealed container slightly increases the carbon dioxide gas concentration in the container. Has the effect of extending the shelf life of the product. Therefore, a method of simply storing raw chicken eggs in a gas-barrier sealed container provided with a humidity control means is also included in the present invention.

That is, the method for maintaining the freshness of raw chicken eggs of the present invention comprises:
In a substantially gas-impermeable sealed container enclosing air,
Or, preferably 5 to 30%, more preferably 10 to 2
A method for maintaining fresh hen's eggs in a substantially gas impermeable hermetically sealed container enclosing air containing 0% concentration of carbon dioxide, wherein the container has the extra humidity in the container. The present invention relates to a method for maintaining freshness, characterized by having humidity control means for removing water.

In one embodiment of the method for maintaining the freshness of raw chicken eggs of the present invention, excess water in the sealed container is removed by using a desiccant as a humidity control means.

In another embodiment of the method for maintaining freshness of raw chicken eggs of the present invention, excess moisture in the sealed container is used as a humidity control means so that the material constituting a part or all of the gas barrier sealed container is hygroscopic. It is removed by using a functional polymer material having a dehumidifying function such as a film or a moisture-permeable film.

In still another embodiment of the method for maintaining freshness of raw chicken eggs of the present invention, a part or all of the air in the sealed container is replaced with nitrogen gas to reduce the nitrogen concentration in the container to about 50%.
By doing so, the oxygen content in the container is reduced, and the effect of preventing the generation and / or propagation of microorganisms such as mold is enhanced.

In still another embodiment of the method for maintaining freshness of raw chicken eggs of the present invention, the oxygen content in the container is reduced by further adding an oxygen scavenger in the sealed container, thereby generating microorganisms such as mold. And / or enhance the effect of preventing reproduction.

In a further aspect of the method for maintaining freshness of raw chicken eggs of the present invention, the oxygen content in the container is reduced by using a carbon dioxide-generating type oxygen absorber as the oxygen absorber contained in the sealed container. At the same time, the effect of preventing the generation and / or propagation of microorganisms such as mold is enhanced by lowering the concentration, and at the same time, the concentration of carbon dioxide in the container is maintained in a preferable range by generating carbon dioxide.

In still another embodiment of the method for maintaining freshness of raw chicken eggs of the present invention, a moisture-dependent oxygen absorber is used in place of the desiccant and oxygen absorber contained in the sealed container, so that The effect of removing excess water and reducing the oxygen content in the container to prevent the generation and / or propagation of microorganisms such as molds is enhanced.

In another embodiment of the method for maintaining freshness of raw chicken eggs of the present invention, a moisture-dependent carbon dioxide-generating type oxygen scavenger is used in place of the desiccant and oxygen scavenger contained in the sealed container. , Removing excess water in the container and reducing the oxygen content in the container to enhance the effect of preventing the generation and / or propagation of microorganisms such as mold,
A carbon dioxide gas is generated to maintain the carbon dioxide gas concentration in the container in a preferable range.

The present invention further relates to a freshly maintained raw chicken egg which is retained by the above-mentioned method for maintaining fresh chicken egg.

[0032]

BEST MODE FOR CARRYING OUT THE INVENTION The method for maintaining the freshness of raw chicken eggs of the present invention will be described in more detail below.

In one embodiment of the method for maintaining the freshness of raw chicken eggs according to the present invention, the eggs and the appropriate amount of desiccant, which are as early as possible after the eggs are laid, are sealed in an airtight container or gas barrier film bag. In this case, the container may be sealed after replacing part or all of the air in the container with nitrogen gas.

In another embodiment of the method for maintaining freshness of raw chicken eggs of the present invention, a chicken egg as early as possible after laying eggs and an appropriate amount of a desiccant are placed in an airtight container or a gas barrier film bag, and a carbon dioxide gas concentration of 5 to 30 is added. % (Preferably 10 to 2
(0%) containing air and / or nitrogen gas to replace the air in the airtight container or the gas barrier film bag, and hermetically packaged.

In another embodiment of the method for maintaining the freshness of raw chicken eggs of the present invention, an airtight container or a gas barrier film bag is charged with eggs as early as possible after laying eggs, an appropriate amount of a desiccant, and an appropriate amount of an oxygen absorber. The air in the airtight container or the gas barrier film bag is replaced with air and / or nitrogen gas having a carbon dioxide gas concentration of 5 to 30% (preferably 10 to 20%), and the container is hermetically sealed.

In another embodiment of the method for maintaining the freshness of raw chicken eggs according to the present invention, the eggs in an airtight container or gas barrier film bag as early as possible after laying the eggs, an appropriate amount of a desiccant, and carbonic acid in the container after hermetically packaging. A carbon dioxide-generating type oxygen scavenger having an amount of carbon dioxide gas such that the gas concentration becomes 5 to 30%, preferably 10 to 20% is filled and sealed. In this case, the container may be sealed after replacing part or all of the air in the container with nitrogen gas. Further, by replacing a part of the air and / or nitrogen gas in the container with an appropriate amount of carbon dioxide which is smaller than the amount required for maintaining the freshness of the raw hen's eggs, the container is sealed, and thus it is necessary to maintain the freshness of the raw hen's eggs. A part of the carbon dioxide gas to be used may be present in the container from the beginning of sealing the container.

In another embodiment of the method for maintaining the freshness of raw chicken eggs of the present invention, a chicken egg as early as possible after laying eggs and an appropriate amount of a water-dependent oxygen absorber are added to an airtight container or a gas barrier film bag, and carbon dioxide gas is added. The air in the airtight container or gas barrier film bag is replaced with air and / or nitrogen gas having a concentration of 5 to 30% (preferably 10 to 20%), and the container is hermetically sealed.

In still another embodiment of the method for maintaining the freshness of raw chicken eggs of the present invention, the eggs are placed as early as possible after laying them in an airtight container or a gas barrier film bag, and the concentration of carbon dioxide in the container after sealed packaging is reduced. A water-dependent carbon dioxide generating type oxygen scavenger having a carbon dioxide gas generation amount of 5 to 30% (preferably 10 to 20%) is filled and sealed. In this case, the container may be sealed after replacing part or all of the air in the container with nitrogen gas. Further, by replacing a part of the air and / or nitrogen gas in the container with an appropriate amount of carbon dioxide which is smaller than the amount required for maintaining the freshness of the raw hen's eggs, the container is sealed, and thus it is necessary to maintain the freshness of the raw hen's eggs. A part of the carbon dioxide gas to be used may be present in the container from the beginning of sealing the container.

The gas-impermeable container in the method for maintaining freshness of raw chicken eggs of the present invention may be a container which is made of a material which does not substantially transmit carbon dioxide, oxygen, nitrogen and the like under a normal environment and can be sealed. There is no particular limitation, and any container usable in the food field satisfying the above conditions can be used. As a container that satisfies such conditions,
For example, a film container such as an aluminum foil, an aluminum-deposited film, a silica-deposited film, a polyvinyl alcohol-based film, a polyethylene / polyvinyl alcohol-based laminated film, or a laminated film combining them, a polyvinyl alcohol-based, a polyvinylidene chloride-based, or a polyacrylonitrile Or a molded container using a barrier nylon-based polymer material, but is not limited thereto.

As the desiccant in the method for maintaining freshness of raw chicken eggs of the present invention, any desiccant that can be used in the food field can be used. Desiccants satisfying such conditions include, but are not limited to, silica gel, calcium chloride, calcium sulfate, and the like.

As the oxygen scavenger in the method for maintaining the freshness of raw chicken eggs of the present invention, any oxygen scavenger usable in the food field can be used. As the oxygen scavenger that satisfies such conditions, any of iron-based and organic-based oxygen scavengers can be used, and as a commercially available oxygen scavenger usable in the present invention, for example, iron-based , Toagosei Co., Ltd. self-reacting, single-function Vitalon (registered trademark) P
H-type, PHR-type, PD-type, PDA-type, T-type, etc., self-reacting type AGELESS (registered trademark) SA-type, SS-type, S-type, Z-type, Z-PT-type, Z-type manufactured by Mitsubishi Gas Chemical Co., Ltd. −P
Examples of the organic type, such as U type, Z-PK type, ZJ-PT type, and ZJ-PK type, include self-reacting type Ageless (registered trademark) GL type manufactured by Mitsubishi Gas Chemical Co., Ltd. It is not limited to.

As the carbon dioxide-generating oxygen absorber in the method for maintaining freshness of raw chicken eggs of the present invention, any carbon dioxide-generating oxygen absorber usable in the food field can be used. As the carbon dioxide-generating oxygen absorber that satisfies such conditions, any of iron-based and organic-type oxygen-absorbing agents can be used. Examples thereof include organic-based self-reacting / multifunctional Vitalon (registered trademark) U type manufactured by Toagosei Co., Ltd., and self-reacting type Ageless (registered trademark) G type manufactured by Mitsubishi Gas Chemical Company, Ltd. But not limited to these.

As the water-dependent oxygen absorber in the method for maintaining freshness of raw chicken eggs of the present invention, any water-dependent oxygen absorber usable in the food field can be used. As the moisture-dependent oxygen absorber that satisfies such conditions, any of iron-based and organic-type oxygen-absorbing agents can be used. For example, as iron-based, moisture-dependent and single-function Vitalon (registered trademark) LT type manufactured by Toagosei Co., Ltd., and moisture-dependent type Ageless (registered trademark) FX type and FX-L type manufactured by Mitsubishi Gas Chemical Company, Ltd. , FJ type, FM type, etc., moisture-dependent Keplon (registered trademark) DR type and DR / S type manufactured by Keplon, etc., and moisture-dependent sescur (registered trademark) D type, DX type, etc., manufactured by Nippon Soda Co., Ltd. But not limited thereto.

As the water-dependent carbon dioxide-generating oxygen absorber in the method for maintaining freshness of raw chicken eggs of the present invention, any water-dependent carbon dioxide-generating oxygen absorber usable in the food field can be used. . As the water-dependent carbon dioxide-generating type oxygen absorber that satisfies such conditions, any of iron-based and organic-type oxygen-absorbing agents can be used. As an oxygen agent,
For example, examples of iron-based materials include, but are not limited to, Vitalon (registered trademark) GS type, GM type, and the like, which are manufactured by Toagosei Co., Ltd.

[0045]

EXAMPLES The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples.

Example 1 Raw chicken eggs (one day after spawning white leghorn; medium size)
Each set is placed on a plastic tray, placed in a 15 cm × 20 cm gas barrier film (EVOH film) bag so as to make the space as small as possible, lightly degassed, and then gas [1] (90% nitrogen + carbon dioxide 10%). %), Gas [2] (nitrogen 80% + carbon dioxide 20%), gas [3]
One of three types of gas (90% air + 10% carbon dioxide) was sealed and sealed, and a sample sealed with normal air was sealed. In addition, gas [1]
And a test section containing gas [3], a test section containing 5 g of silica gel as a desiccant for preventing dew condensation in the sealed gas barrier film bag was also set, and an experiment was conducted under six conditions in total. Was. The desiccant was placed in a breathable paper pack to avoid direct contact with the eggs and placed under a plastic tray.

After sealing, pack the bags containing the raw chicken eggs of all the test plots into 2
It was left in a thermostat at 5 ° C. However, in order to induce dew condensation in each raw egg-containing bag, all raw egg-containing bags in the test section were kept at 15 ° C for 2 hours on the first and second days after the start of the test (after sealing). To give a temperature change.

After 3 days, 5 days, 7 days, and 10 days after the start of the test, the gas compositions in all the raw egg-containing bags in the test plot were measured, and then opened to take out the raw chicken eggs. The removed eggs were evaluated by visual observation for the presence or absence of condensation on the surface and the occurrence of mold, and then divided to measure the egg white height, the yolk height and the yolk diameter, and the Howe unit was obtained by calculation.

The results are shown in Tables 1 and 2 below and in FIG. 1, where the value of each item is shown as an average of the values obtained for five eggs.

[Test zone] Test zone (1) Sealed packaging (normal air) Test zone (2) Carbon dioxide: nitrogen = 1: 9 (gas [1]) Test zone (3) Carbon dioxide: nitrogen = 2: 8 (Gas [2]) Test plot (4) Carbon dioxide: nitrogen = 1: 9 (with desiccant ^* ) (Gas [1]) Test plot (5) Carbon dioxide: air = 1: 9 (Gas [3]) Test plot (6) Carbon dioxide: air = 1: 9 (with desiccant ^* ) (gas [3]) (* desiccant is 5 g of silica gel)

[0051]

[Table 1]

[0052]

[Table 2]

The raw chicken egg how units were prepared in all the test plots (test plots 2 to 6) in which the mixed gas containing carbon dioxide gas was sealed and packaged.
However, the value was higher than that in the air-sealed (without carbon dioxide gas) test (1), and the value was maintained at 70 or more even after 10 days. However, even in the air-sealed (carbon dioxide non-enclosed) test plot (1), a relatively high How unit value of 65 or more was still maintained even after 7 days. In all of the plots in which the desiccant was not added, dew condensation occurred 3 days later, and mold formation was observed 5 days later. Even in the test plot containing 5 g of silica gel, dew condensation occurred 5 days later, and mold developed 7 days later.

Example 2 Raw chicken eggs (one day after spawning white leghorn; medium size)
Each set is placed on a plastic tray and placed in a 15 cm × 20 cm gas barrier film (EVOH film) bag so that the space is as small as possible.
g or 20 g and lightly degassed.
(0% + carbon dioxide gas 10%) were sealed and sealed, and those sealed with ordinary air without a desiccant were sealed and tested. Experiments were performed on five conditions in total. The desiccant was placed in a breathable paper pack to avoid direct contact with the eggs and placed under a plastic tray. The average of the measured values of the gas composition of the sealed gas in each test section in which the above mixed gas (containing 10% of carbon dioxide gas) was sealed was a carbon dioxide gas concentration of 9.64.
%, Oxygen gas concentration 18.98%, nitrogen gas concentration 71.3
It was almost uniform at 6%. A non-treated control group was packaged with the same packaging material, and a section containing no desiccant and not sealed (open storage) was prepared.

Raw chicken egg-containing bags in the test and control groups were kept at 25 ° C.
In a constant temperature room. However, in order to induce dew condensation in each raw egg-containing bag, all raw egg-containing bags of the test and control groups were placed in a 15 ° C constant temperature room for 2 hours on the first and second days after the start of the test. It was left to give a temperature change.

After 3 days, 5 days, 7 days, and 14 days after the start of the test, the gas compositions in all the raw egg-containing bags in the test plot and the control plot were measured, and then opened to take out the raw chicken eggs. At the time of removal, the presence or absence of dew condensation on the inner surface of each bag and the surface of the egg, the presence or absence of mold is evaluated by visual observation, the egg is split, the albumen height, the yolk height, the yolk diameter are measured, and calculated. I asked for a Howe unit.

The results are shown in Tables 3 and 4 below and in FIG. 2, where the value of each item is shown as an average of the values obtained for five eggs.

[Test plot] Control plot No treatment (no desiccant; open storage) Test plot (1) Sealed packaging (no desiccant; normal air) Test plot (2) Silica gel 10 g (carbon dioxide 10% mixed air) Section (3) Silica gel 20 g (carbon dioxide 10% mixed air) Test section (4) Calcium chloride 10 g (carbon dioxide 10% mixed air) Test section (5) Calcium chloride 20 g (carbon dioxide 10% mixed air)

[0059]

[Table 3]

[0060]

[Table 4]

The raw chicken egg how units were sealed in a mixed gas containing carbon dioxide and sealed in a desiccant-containing test zone (2)-
(5) was clearly higher than the control group, and maintained a value of 70 or more even after 14 days. However, even in the air-sealed (without carbon dioxide gas) test (1),
Even after a lapse of days, the HOW value was still relatively high at 65 or more.

In the control plot, the test plot (3) containing 20 g of silica gel, and the test plots (4) and (5) containing calcium chloride, dew condensation and mold generation were not observed throughout the test period, but air-sealed. In the test section (1) and the test section (2) containing 10 g of silica gel,
Dew condensation and mold occurred. The amount of water absorption per unit weight of silica gel and calcium chloride is as follows: silica gel (0.3 g
/ g), calcium chloride (1.0 g / g) was clearly higher.

Example 3 Five raw chicken eggs (white leghorn egg on the day of spawning; medium size)
Put it on a plastic tray in a set, put it in a gas barrier film (EVOH film) bag of 15 cm × 20 cm so as to make the space as small as possible, and furthermore, Vitalon (registered trademark) as a moisture-dependent carbon dioxide generating oxygen absorber
From the GS series (manufactured by Toa Gosei Co., Ltd.), use Vitalon GS-1500, which is considered appropriate based on the content of the gas barrier film bag used for the test, and put it under the plastic tray and put the bag on. The test section was sealed (filled gas was 100% ordinary air). In addition, a test section in which calcium chloride (5 g or 10 g) was added as a desiccant and sealed was set in combination with Vitalon GS-1500, and experiments were performed under three conditions as a whole. The desiccant was placed in a breathable paper pack to avoid direct contact with the eggs and placed under a plastic tray. An untreated control group was packaged with the same packaging material, and an open storage (not sealed) containing the above-described oxygen absorber and desiccant was prepared.

The bags containing the raw chicken eggs in the test group and the control group were placed at 25 ° C.
In a constant temperature room. However, in order to induce dew condensation in each raw egg-containing bag, all raw egg-containing bags of the test and control groups were placed in a 15 ° C constant temperature room for 2 hours on the first and second days after the start of the test. It was left to give a temperature change.

After 5 days, 7 days, 9 days, and 15 days after the start of the test, the gas compositions in all the raw egg-containing bags in the test group and the control group were measured, and then opened to take out the raw chicken eggs. At the time of removal, the presence or absence of dew condensation on the inner surface of each bag and the surface of the egg, the presence or absence of mold is evaluated by visual observation, the egg is split, the albumen height, the yolk height, the yolk diameter are measured, and calculated. Howe units and egg yolk coefficients were determined.

The results are shown in Tables 5 and 6 below and in FIGS.
The values for each item are shown as the average of the values obtained for 5 eggs.

[Test plot] Control plot No treatment (No oxygen scavenger and desiccant; open storage) Test plot (1) Vitalon GS-1500 Test plot (2) Vitalon GS-1500 + Calcium chloride 5 g GS-1500 + 10 g of calcium chloride

[0068]

[Table 5]

[0069]

[Table 6]

The Howe unit of raw chicken eggs is Vitalon GS
All the test plots containing -1500 remained higher than the control plots, and maintained a value of 70 or more even after 15 days. The yolk coefficient shows the same tendency as the Howe unit,
After 15 days, finally, a remarkable two-fold difference was observed between the test group and the control group. In all test and control plots, no dew condensation or mold development was observed throughout the test period.

[0071]

When the method for maintaining freshness of raw chicken eggs of the present invention is used, a carbon dioxide atmosphere having a concentration effective for maintaining freshness of raw chicken eggs can be maintained for a relatively long time by an inexpensive and simple method. Prevention of dew condensation in the container, which causes generation of microorganisms such as mold and rot, makes it possible to maintain the freshness of raw chicken eggs at room temperature for a relatively long period of time.

[Brief description of the drawings]

FIG. 1 is a diagram showing the effects of the carbon dioxide concentration and the desiccant in a sealed container on the Howe unit value of raw chicken eggs in the method for maintaining fresh chicken eggs of the present invention.

FIG. 2 is a diagram showing the effect of the type and amount of a desiccant on the Howe unit value of raw chicken eggs in the method for maintaining freshness of raw chicken eggs of the present invention.

FIG. 3 is a view showing the effect of a water-dependent carbon dioxide-generating type oxygen absorber and a desiccant on the Howe unit value of raw chicken eggs in the method for maintaining fresh chicken eggs freshness of the present invention.

FIG. 4 is a diagram showing the effect of a water-dependent carbon dioxide-generating oxygen absorber and a desiccant on the yolk coefficient of raw chicken eggs in the method for maintaining fresh chicken eggs freshness of the present invention.

Claims (10)

[Claims] 1. A method for maintaining the freshness of raw hen's eggs, wherein the raw hen's eggs are held in a gas-barrier sealed container filled with air,
A method for maintaining freshness, characterized in that said gas-barrier sealed container has a humidity control means for removing excess humidity in said sealed container. 2. The air in the gas-barrier sealed container is 30
% Or less carbon dioxide gas,
The freshness maintaining method according to claim 1. 3. The method for maintaining freshness according to claim 2, wherein the concentration of carbon dioxide in the gas-barrier sealed container is 5 to 30%. 4. The method according to claim 1, wherein a part or all of the air in the gas-barrier sealed container is replaced with nitrogen gas, and the gas-barrier sealed container contains nitrogen gas at a concentration of 50% or more. The freshness maintaining method according to any one of claims 1 to 3. 5. The method of controlling humidity in a gas-barrier sealed container, wherein the gas-barrier sealed container includes a desiccant selected from calcium chloride, silica gel, or a combination thereof. The freshness maintaining method according to any one of claims 1 to 4. 6. The method for maintaining freshness according to claim 5, wherein an oxygen scavenger is further contained in the gas-barrier sealed container. 7. The oxygen scavenger is a carbon dioxide-generating type oxygen scavenger, wherein a part or all of the carbon dioxide in the gas-barrier sealed container is supplied by the carbon dioxide scavenger. The freshness maintaining method according to claim 6, wherein 8. A gas-barrier sealed container comprising a moisture-dependent oxygen scavenger as humidity control means.
The freshness maintaining method according to claim 1. 9. A gas-barrier sealed container comprising a moisture-dependent carbon dioxide-generating type oxygen absorber as a humidity control means, wherein a part or all of the carbon dioxide in the gas-barrier sealed container is reduced by the moisture-dependent carbon dioxide. The freshness maintaining method according to any one of claims 1 to 4, wherein the freshness is supplied by a gas generating type oxygen scavenger. 10. As a means for controlling humidity in a gas-barrier sealed container, a part or all of the gas-barrier sealed container is provided with a function having a dehumidifying function in the container such as a moisture-absorbing film or a moisture-permeable film. The freshness maintaining method according to any one of claims 1 to 9, wherein the method is formed using a molecular material.