JPH0789852B2 - Refrigeration storage method of egg liquid - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for refrigerating and storing egg liquid.

[Conventional technology]

If egg liquid (whole egg, egg yolk or egg white) is stored at a temperature above 10 ° C, the growth of contaminating bacteria will be activated and early rot will occur in a short time, so the egg liquid should be as cold as possible immediately after breaking eggs. It is recommended to save. However, it is said that the freezing and freezing point of egg liquid is around -0.7 ° C, and the egg liquid freezes and solidifies when stored at a temperature below this freezing and freezing point. By the way, for example, when the yolk is frozen, its yolk protein is frozen and denatured, so that the yolk liquid after thawing has a significantly higher viscosity than the raw yolk and has a reduced emulsifying power. It is not suitable as a raw material for emulsified products. In addition, for whole eggs, whole egg liquid was frozen after pasteurization and frozen and stored at -20 ° C or lower,
So-called sterilized frozen whole eggs are commercially available. Although this product is cheap in terms of cost, the whole egg liquid after thawing it has a higher viscosity than raw whole eggs, and also has a lower foaming power and emulsifying power, so it is a high-class confectionery product. It is not suitable as a raw material for kneaded products. Furthermore, as for egg white, so-called frozen egg white obtained by freezing egg white liquid and storing it frozen at -20 ° C or lower is commercially available. Even if frozen, egg white protein does not freeze-denaturate, so after thawing, it can exhibit almost the same functional characteristics as raw egg white, but frozen egg white requires thawing work before use, and equipment and extra equipment for that purpose are required. It takes time and effort.

Under these circumstances, in recent years, a method has been developed in which the egg liquid is preserved at a low temperature in a liquid state without impairing the functional characteristics of the egg liquid by refrigeration (chilling) instead of freezing. For example,
A refrigerating method utilizing freezing point depression by blending additives, specifically, a method for producing refrigerated egg yolk disclosed in JP-A-50-64460 is known.

[Problems to be solved by the invention]

However, refrigerated eggs produced by these conventional methods are -5 ° C
Even if it is stored at a low temperature of 25 ℃, it is liquid but contains a large amount of sugar, salt or (and) edible oil, so not only the range of use of the final product is extremely limited, but also expensive in terms of cost. Stick to Therefore, it is very common to refrigerate the egg liquid itself at about 0 ° C. or higher, especially at 5 to 10 ° C., so that it can be used immediately as a raw material for various foods so as not to be frozen. However, even in such a refrigeration method, even if pre-sterilized, the shelf life of refrigerated products is 5 ° C for 8 days, 10 ° C for 10 days even if the initial number of bacteria is considerably low due to the low temperature resistant bacteria remaining in the egg liquid. Since the allowable storage period is as short as 4 days, it is the situation that not only refrigerated egg makers and users but also product storage managers and delivery companies find it inconvenient due to the short shelf life. is there.

Therefore, an object of the present invention is to provide a method for refrigerating and preserving egg liquid, which is capable of producing refrigerated eggs having good storability and having the same or substantially the same physical properties as those of raw egg liquid.

[Means for solving problems]

When the inventors started the study in accordance with the above-mentioned purpose, the freeze-freezing point of the egg liquid was about -0.7 ° C, and
The egg solution was rapidly cooled in a refrigerant at 8 ° C, at which time the product temperature of the egg solution at the time when the egg solution began to solidify was measured and confirmed, and then various cooling tests were repeated on the egg solution. However, when the egg liquid is rapidly cooled in a refrigerant (for example, Freon gas) at about −18 to −20 ° C., the egg liquid becomes −
Although it begins to freeze at around 0.7 ° C, when the egg liquid is cooled in an atmosphere of -1 to -4 ° C, specifically, for example, it is cooled by putting it in a refrigerator whose internal temperature is -1 to -4 ° C. In this case, it was surprisingly found that a refrigerated egg having a product temperature in the temperature range and maintaining a liquid state for a long period of time can be obtained.

The inventors have found that the product temperature produced as described above is -1 to -1.
Further studies were conducted on the breeding status of contaminating bacteria during storage of refrigerated eggs at -4 ° C in comparison with refrigerated eggs having a product temperature higher than the freezing freezing point. Resistant bacteria have further been found to have their growth suppressed more than expected.

The present invention has been completed based on these findings, and is characterized in that only egg liquid is cooled in an atmosphere of -1 to -4 ° C and stored in a liquid state in the atmosphere. A method for refrigerating egg liquid is provided.

In the present invention, the term "egg fluid" means the individual whole egg, egg yolk or egg white having the following meanings, or a generic term for them.

The “whole egg” means an egg solution containing egg yolk and egg white obtained by breaking a raw egg shell. Since the composition ratio of one raw egg is usually 1 to 3 by weight ratio, the egg yolk to egg white is generally referred to as the egg solution having this composition ratio, but in the present invention, egg yolk to egg white is 1: 1 to 1: 4
It also includes egg liquid consisting of.

"Egg yolk" means the egg white obtained by separating and removing the egg white from the egg liquid obtained by breaking raw eggs with a shell. In addition, this egg yolk,
It also includes egg yolk containing about 10% or less of egg white based on the total weight that is inevitably mixed in operation.

The "egg white" means the egg yolk separated and removed from the egg liquid obtained by breaking the shell eggs. In addition, in this egg white,
It also includes egg white containing about 10% or less of egg yolk based on the total weight that is inevitably mixed in operation.

Further, the "refrigerated egg" that is the target food of the method of the present invention,
It means egg liquid that is cryopreserved in a liquid state without being frozen.

Furthermore, in the following description of the present invention, "sterilized egg" means an egg solution that has been heat-treated to such an extent that egg protein is not heat-denatured, and "unsterilized egg" means an egg solution that has not been subjected to this heat treatment. Means

The method for refrigerating egg liquid according to the present invention will be described below.

The raw egg liquid is preferably fresh immediately after breaking a raw egg with shells that has not passed much since the spawning. Egg fluid in which egg protein has already been denatured, such as thawed frozen egg or dried egg rehydrated, salt,
Egg fluid containing saccharides is unsuitable as a raw egg fluid.

Depending on the desired egg liquid, for example, in the case of whole eggs, egg yolk and egg white are mixed at a predetermined ratio, preferably prepared by uniform mixing, and in the case of egg yolk or egg white, split eggs, after separation, preferably Egg liquids are prepared by mixing the egg whites or egg yolks inevitably mixed with each other to make them uniform.
It should be noted that when preparing any of the egg liquid, eggshell debris, Karaza,
It may be overtreated for the purpose of removing inedible impurities such as yolk membrane.

The egg solution thus prepared is stored in an appropriate container and then kept as it is in an atmosphere of -1 to -4 ° C. However, as is clear from the results of Test Examples 1 and 2 which will be described later, it is preferable to use the egg solution as a sterilized egg in order to produce a product that does not freeze-coagulate even at a lower temperature and can be stored for a long period of time. To sterilize eggs, use a heating device such as a plate heater. For whole eggs and egg yolk, 55-65 ℃ for 3-10 minutes, and for egg white, 50-60 ℃ for 2-10 minutes. Heat treatment may be performed.

In this way, sterilized eggs or unsterilized eggs may be directly held in an atmosphere of -1 to -4 ° C.
Even if the eggs are stored in a 100-ml flask and sealed tightly, about 50 g, whether they are sterilized eggs or unsterilized eggs when cooled in a refrigerator that keeps the internal temperature at -1 to -4 ° C Since it takes about 7 hours for the product temperature to reach -4 ° C, the egg liquid is pre-cooled from the viewpoint of shortening the working time and preventing deterioration of the egg liquid, and then -1 to -4 ° C. Cool in an atmosphere. The pre-cooling treatment may be performed, for example, by cooling the egg liquid to a temperature lower than 10 ° C., preferably 0 to 5 ° C., using a cooling device such as a plate cooler. Incidentally, -1
The atmosphere of to -4 ° C can be maintained at a constant temperature as much as possible, although the temperature may be varied within this temperature range.

The refrigerated egg produced as described above is in a liquid state even though it has a product temperature of -1 to -4 ° C, and its constitution is composed only of egg liquid. When storing and delivering such refrigerated egg products, particular attention should be paid to the maintenance of the product temperature.

〔The invention's effect〕

How the refrigerated eggs obtained by the method of the present invention can exhibit excellent effects in terms of storability and physical properties will be described with reference to the results of Test Examples 1 to 5 below.

Test Example 1 (Storability) First, 6 kinds of egg solutions as shown below were prepared.

(A) Unsterilized whole egg The whole egg liquid obtained by breaking raw eggs with shells and passing through a strainer after stirring (b) Sterilized whole egg (b) Unsterilized whole egg at 62.5 ° C Heated through a plate heater for minutes, then cooled to room temperature (20 ° C) (C) Unsterilized egg yolk Stir the yolk obtained by separating and removing the egg white from the egg liquid obtained by breaking the egg After passing through a strainer (d) Sterilized egg yolk (c) Unsterilized egg yolk is heat-treated by passing it through a plate heater at 62.5 ° C for 5 minutes and then cooled to room temperature (20 ° C) (e) Unsterilized egg white The egg white obtained by separating and removing the egg yolk from the egg liquid obtained by splitting raw eggs with shells and passing through a strainer after stirring (f) Sterilized egg white (e) Unsterilized egg white at 55.5 ° C Heated through a plate heater for minutes and then cooled to room temperature (20 ℃). Was the sample that was collected by 50g in 100ml beaker, unpasteurized eggs in each egg fluid four and sterilization eggs were prepared samples of five pieces. Each of these samples was placed in a refrigerator in which unsterilized eggs were kept at 5 ° C., 0 ° C., −2 ° C. and −4 ° C., and the sterilized eggs were also placed in a refrigerator held at −6 ° C. It was stored as it was for 20 days.

When the state of each sample during the storage period was observed, the results were as shown in Table 1 below.

Remark 1: Even if the sample was placed in a refrigerator kept at -6 ° C, the product temperature was -6 ° C by 12 hours after the placement.

Note 2: In the table, "liquid" means liquid, "semi" means semi-frozen, and "freeze" means frozen.

Test Example 2 (Proliferation of Bacteria during Storage) For each egg solution prepared in Test Example 1 above, 50 g of each egg solution was dispensed into a 100 ml beaker, and four samples were prepared for each egg solution. Each of them was placed in a refrigerator kept at 0 ° C, 0 ° C, -2 ° C, and -4 ° C, and stored as it was for 20 days.

When the viable cell count per 1 ml of each sample was measured during this storage period, the results are shown in Table 2 below.

Remark 1: The number of viable bacteria per 1 ml of sample just before placing each egg liquid in the refrigerator is 6.4 × 10 ³ for (a), 1.4 × 10 ³ for (b), and
7.6 × 10 ³ , (d) was 2.7 × 10 ² , (e) was 4.7 × 10 ^3, and (f) was 3.8 × 10 ² .

Remark 2: "-" in the table means unmeasured, and those with an underline below the number mean that a rotten odor was felt.

Test Example 3 (Viscosity and Foaming Power) First, 6 types of samples as shown below were prepared.

(A) Frozen whole egg The unsterilized whole egg of (a) of Test Example 1 was frozen in a refrigerant at -20 ° C. (B) The refrigerated whole egg The unsterilized whole egg of (a) of Test Example 1 was First, heat it through a plate heater at 62 ° C for 5 minutes, then heat this through a plate cooler to 4 ° C, then -4 ° C.
(C) Frozen egg yolk frozen in the refrigerant at -20 ° C (d) Refrigerated egg yolk test The unsterilized egg yolk of (c) of Example 1 was first heat-treated at 62 ° C. for 5 minutes by passing it through a plate heater, which was then passed through a plate cooler and cooled to 4 ° C., and further -4 ° C.
(E) Frozen egg white of (e) Frozen egg white of Test Example 1 (e) frozen in a refrigerant of -20 ° C. (f) Chilled egg white test The unsterilized egg white of (e) of Example 1 was first heat-treated by passing through a plate heater at 52 ° C. for 5 minutes, then passed through a plate cooler and cooled to 4 ° C., and further -4 ° C.
Placed in a refrigerator kept at -4 ° C. and then stored 1.5 kg of each sample in a 2 liter round can and sealed,
The frozen sample was stored in a freezer at −20 ° C. for 21 days, and the frozen sample was stored in a refrigerator kept at −4 ° C. for 21 days, taken out, opened, and returned to room temperature.

When the egg liquid samples thus obtained were measured for viscosity and foaming power, the results are shown in Table 3 below.

Remark 1: For the whole egg and egg white samples, the downflow seconds were measured using the Ostwald viscometer, and for the yolk sample, the cps was measured using the B type viscometer.

Remark 2: The foaming power was indicated by the height (mm) of foam when 500 g of each sample was put in a Hobart mixer and stirred first at medium speed for 1.5 minutes and then at high speed for 1.5 minutes. In addition, -means unmeasured.

Test Example 4 (Appropriateness as Cake Raw Material) First, the following three types of samples were prepared.

(I) Whole egg liquid Fresh whole egg liquid immediately after breaking raw eggs with shells (ii) Frozen whole egg-thawed whole egg liquid (i) Whole egg liquid is frozen in a refrigerant at -20 ° C, Then −
Whole egg liquid obtained by storing in a freezer at 20 ° C. for 21 days and then thawing (iii) chilled whole egg liquid (i) was first heat treated by passing through a plate heater for 5 minutes at 62 ° C. Then, the whole egg solution was cooled by passing it through a plate cooler to 4 ° C, put it in a refrigerator kept at -4 ° C to bring the product temperature to -4 ° C, stored for 21 days and then taken out. , 450g of each whole egg liquid sample, 310g of sugar, 100g of starch syrup
Sponge cakes were each fired by a conventional method using 190 g of wheat flour and wheat flour, and the apparent specific gravity and specific volume (cc / g) of each obtained cake were measured. The results are shown in Table 4 below. .

Test Example 5 (Emulsifying power) First, the following three types of samples were prepared.

Egg yolk liquid Fresh yolk liquid immediately after separating and removing egg white from the egg liquid obtained by breaking raw eggs with shells Frozen yolk-thawed yolk liquid Egg yolk liquid is frozen in a refrigerant at -20 ° C, then -20
Stored in a freezer at ℃ for 21 days and then taken out and thawed. Egg yolk liquid of chilled egg yolk liquid was first passed through a plate heater at 60 ° C for 5 minutes for heat treatment, and then passed through a plate cooler. Egg yolk liquid obtained by taking out and refrigerating to 4 ° C., then putting it in a refrigerator kept at −4 ° C. and keeping the product temperature at −4 ° C. for 21 days and then taking it out. Then, 200 g of each yolk liquid sample above, 900 g of salad oil 5%
170 g of vinegar having an acidity and 30 g of salt were used to produce mayonnaise in a conventional manner. A part of each of the resulting mayonnaise products is sampled and the viscosity is measured, and each product is left in a refrigerator kept at -15 ° C to observe the separation state of oil and fat, and the separation is started. When the cold resistance of each product was examined by measuring the number of days until, the results were as shown in Table 5 below.

Note: Viscosity was measured using a B type viscometer.

From the above Test Examples 1 and 2, the refrigerated eggs obtained by the method of the present invention are conventionally said to be the freeze-freezing point of egg liquid -0.7.
It is a liquid that has a product temperature 1 to 4 ° C lower than that, and it can be stored for more than 20 days in that state, and the growth of bacteria during the storage period is also unexpectedly low. It can be seen that the shelf life of the product is long. These effects are more remarkable in the sterilized eggs.

Further, from the above Test Examples 3, 4 and 5, since the refrigerated eggs obtained by the method of the present invention are in a liquid state without being frozen, the yolk protein is not denatured and the egg liquid is whole egg or yolk. However, it is understood that its physical properties such as viscosity, foaming power and emulsifying power are the same as or almost the same as those of raw egg liquid, and therefore it has an advantage that it can be used as a raw material for confectionery or emulsified products. To be done. .

Furthermore, since the refrigerated eggs obtained by the method of the present invention are not frozen, there is no need for thawing work, and therefore there is an advantage that equipment and extra labor for it can be omitted. This advantage is especially recognized in the case of refrigerated egg white, which is not significantly different from frozen egg white in physical properties.

Furthermore, since the refrigerated egg obtained by the method of the present invention has no additives blended, its utilization range is exactly the same as that of the raw egg liquid, and the conventional refrigerated egg containing the additive is used. Compared with this, the use can be further expanded.

In general, the refrigerated eggs obtained by the method of the present invention can be stored for a long period of time, and have characteristics not found in any conventional refrigerated eggs that have physical properties equivalent to raw egg liquid. I have.

〔Example〕

 Hereinafter, the present invention will be described in more detail with reference to examples.

Example 1 Whole egg liquid obtained by breaking raw eggs with shells was stirred in a tank equipped with a stirrer to mix and homogenize yolk and egg white, and then passed through a strainer of 80 mesh to remove impurities. .

Then, this whole egg liquid was immediately passed through a plate cooler without sterilization and cooled to 0 ° C, and then 20 kg in a 5 gallon can.
Each was separated and sealed. This product was placed in a refrigerator kept at -3 ° C and stored as it was.

When the can was taken out on the 18th day of storage and opened, the whole egg liquid had a product temperature of -3 ° C and remained in a liquid state, and no alteration or deterioration phenomenon was observed.

Example 2 Egg liquid obtained by breaking open eggs with shells was separated into yolk liquid and egg white liquid, which were respectively stirred and homogenized in a tank equipped with a stirrer and then passed through a strainer of 80 mesh. To remove impurities.

(1) The egg yolk liquid was immediately passed through a plate cooler without sterilization and cooled to 1 ° C., and then 9 Kg each was dispensed in a 10-liter round can and sealed. This product was placed in a refrigerator kept at -2 ° C and stored as it was.

When the can was taken out on the 20th day of storage and opened, the egg yolk liquid maintained a liquid state at a product temperature of -2 ° C, and no alteration or deterioration was observed.

(2) The egg white liquor was immediately passed through a plate cooler without sterilization, cooled to 2 ° C., and 9 Kg each was dispensed in a 10-liter round can and sealed. This product was placed in a refrigerator kept at -4 ° C and stored as it was.

When the can was taken out on the 20th day of storage and opened, the egg white liquor kept a liquid state at a product temperature of -4 ° C, and no alteration or deterioration was observed.

Example 3 Whole egg liquid obtained by breaking raw eggs with shells was stirred in a tank with a stirrer to mix and homogenize egg yolk and egg white, and then passed through a strainer of 80 mesh to remove impurities. .

Then, this whole egg solution was heat-treated by passing it through a plate heater at 62.5 ° C. for 5 minutes, then immediately passed through a plate cooler to cool to 5 ° C., and 9 Kg of each 10-liter round can was collected and sealed. This product was placed in a refrigerator kept at -4 ° C and stored as it was.

When the can was taken out on the 20th day of storage and opened, the whole egg liquid was kept in a liquid state at a product temperature of -4 ° C, and no alteration or deterioration phenomenon was observed.

Example 4 Egg fluid obtained by breaking open eggs with shells was separated into yolk fluid and egg white fluid, and each was stirred and homogenized in a tank equipped with a stirrer, and then 80 mesh The contaminants were removed by passing through a strainer.

(1) The egg yolk solution was heat-treated by passing it through a plate heater at 62.5 ° C. for 5 minutes and then immediately passed through a plate cooler to be cooled to 1 ° C., and 20 kg of each was collected in a 5 gallon can and sealed. This product was placed in a refrigerator kept at -5 ° C and stored as it was.

When the can was taken out on the 20th day of storage and opened, the egg yolk liquid maintained a liquid state at a product temperature of -5 ° C, and no alteration or deterioration was observed.

(2) The egg white liquor was heat-treated by passing it through a plate heater at 55.5 ° C. for 3.5 minutes, then immediately passed through a plate cooler to cool to 1 ° C., and 20 kg of each was separated into 5 gallon cans and sealed. This product was placed in a refrigerator kept at -4 ° C and stored as it was.

When the can was taken out on the 20th day of storage and opened, the egg white liquor kept a liquid state at a product temperature of -4 ° C, and no alteration or deterioration was observed.

Claims (6)

[Claims] 1. A method for refrigerating and storing egg liquid, which comprises cooling only egg liquid in an atmosphere of -1 to -4 ° C. and storing the egg liquid in a liquid state. 2. The method of refrigerating and storing egg liquid according to claim 1, wherein the egg liquid is pre-cooled and then cooled in an atmosphere of -1 to -4 ° C. 3. The method of refrigerating and storing egg liquid according to claim 1 or 2, wherein the egg liquid is whole egg. 4. The method of refrigerating and storing egg liquid according to claim 1 or 2, wherein the egg liquid is egg yolk. 5. The method of refrigerating and storing egg liquid according to claim 1 or 2, wherein the egg liquid is egg white. 6. The first claim in which the egg liquid is a sterilized egg.
Item 6. A method for refrigerating and storing egg liquid according to any one of Items 5 to 5.