JP2526048B2 - Food freezing method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a food freezing method for freezing foods such as vegetables and meats, and more specifically, freezing liquid for secondary refrigeration (refrigerant liquid). The present invention relates to a food freezing method, which is capable of shortening the freezing processing time of foods and improving the freezing efficiency of foods.

[Conventional technology]

Conventionally, as a method of freezing foods such as vegetables and meats,
Various methods (air freezing method, blast freezing method, metal plate contact freezing method, secondary refrigerant liquid freezing method) are known, but since liquid has a larger specific heat / heat transfer coefficient than air, A secondary freezing liquid (refrigerant liquid) freezing method is often used from the viewpoint that quick freezing can be obtained by using a liquid even at the same temperature.

And, the freezing method, a freezing food is immersed in a freezing liquid such as a propylene glycol aqueous solution or an alcohol aqueous solution to be frozen, and a freezing food is sprayed with the freezing liquid to freeze the frozen food. There is an injection type freezing method, but generally, as shown in FIG.
At least a part is provided with a freezing food transport conveyor so as to be immersed in a freezing liquid such as an antifreeze liquid such as a propylene glycol aqueous solution or an alcohol aqueous solution in the tank, and a pressing conveyor is provided above the conveyor, Driving the freezing food transport conveyor, supplying food such as meat vacuum-packed with a packaging material such as a vinyl sheet from the freezing food supply section of the conveyor, and sandwiching and transporting between the freezing food transport conveyor and the pressing conveyor. Then, an immersion type freezing method is often used in which the frozen food is conveyed at a portion of the conveyer for freezing, which is immersed in the freezing liquid, and the frozen food can be taken out at a portion for taking out frozen food from the conveyor.

[Problems to be solved by the invention]

However, the above-mentioned food freezing method has the following problems, although the food can be easily frozen. That is, in order to eliminate contact between the frozen food and the freezing liquid, it is necessary to individually package the frozen food in a liquid-resistant packaging material during immersion in the freezing liquid, so that workability is improved. Is reduced.

In order to reduce the amount of drip that occurs during thawing of frozen food, it is necessary to prevent the formation of an air layer between the frozen food and the packaging material as much as possible. Since it is necessary to process frozen foods in a vacuum pack or the like, not only the cost becomes high, but also the pretreatment tends to be complicated.

The present invention has been made in response to the above points, the object of the object is almost no air layer between the frozen food and the packaging material without processing such as vacuum packaging. It is an object of the present invention to provide a food freezing method capable of freezing the frozen food in a free state.

[Means for solving problems]

Then, the food freezing method as a means for achieving the above-mentioned object is a frozen food transport conveyer arranged so that at least a part thereof is immersed in the freezing liquid in the food freezing tank in the food freezing tank ( It is a concept that includes various kinds of carriers) and a frozen food is surrounded by a liquid-resistant packaging material that is interposed between a pressing member such as a pressing conveyor arranged above the freezing food carrying conveyor. The openings other than the rear end of the liquid-resistant packaging material in the traveling direction are sealed, and the air between the liquid-resistant packaging material and the frozen food is discharged to the outside by the hydraulic pressure of the freezing liquid. Then, the frozen food is sealed, and the frozen food is frozen while being transported by the frozen food transport conveyor via the liquid-resistant packaging material.

Here, in the above-mentioned configuration, if necessary, a means for discharging air between the liquid-resistant packaging material and the frozen food to the outside to keep the frozen food in a sealed state is a hydraulic pressure by the freezing liquid. And the injection pressure of the refrigerant by injecting a refrigerant such as a freezing liquid or a freezing gas into the frozen food through the liquid resistant packaging material. Further, as the liquid-resistant packaging material, two vinyl sheets on the upper and lower sides or one vinyl sheet having a structure in which one side in the traveling direction is folded are used. Further, as the freezing liquid to be sprayed onto the frozen food, the freezing liquid filled in the food freezing tank is circulated by a pump and used.

[Action]

And the food freezing method of the present invention based on the above configuration,
A liquid-resistant packaging material inserted between the freezing food transport conveyor and the pressing member surrounds (encloses, holds, etc.) the frozen food by driving the freezing food transport conveyor, and uses the freezing liquid in the tank. The liquid pressure acts to freeze the food for freezing into a liquid-resistant packaging material in a hermetically sealed state and freeze it with the freezing liquid in the food freezing tank.

As described above, the food freezing device of the present invention is a conventionally used immersion freezing method, in which a liquid-resistant packaging material inserted between the freezing food transport conveyor and the pressing member is inserted (usually two upper and lower sheets). The continuous sheet of the above) is inserted into the liquid-resistant packaging material, and the frozen food and the liquid-resistant packaging material are frozen by the liquid pressure of the freezing liquid in a sealed pack state. It has a feature in that it has a special effect, and this point exerts a special action.

〔Example〕

Hereinafter, examples in which the method of the present invention is embodied will be described with reference to the drawings.

1 to 3 show an embodiment of a food freezing apparatus used for embodying the method of the present invention, FIG. 1 is a schematic vertical sectional view, FIG. 2 is a partially enlarged view of FIG. Figure 3 is of Figure 1
It is an AA line schematic sectional drawing.

First, when describing the present embodiment, the food freezing device used in the present embodiment will be described. This food freezing apparatus is roughly divided into a food freezing tank 1, a freezing food transport unit 2, a freezing liquid injection unit 3, and a liquid resistant packaging material transfer unit 4.

The food freezing tank 1 is installed inside the apparatus main body 5 and is supplied with a refrigerant from a refrigerator (not shown) separately installed inside the apparatus main body 5 to supply an antifreeze solution such as an aqueous propylene glycol solution or an aqueous alcohol solution in the tank 1. A cooling coil 6 for cooling the (freezing liquid) and a stirrer 7 for stirring the antifreezing liquid and keeping the liquid temperature constant are provided. The wall body 8 forming the food freezing tank 1 has a double structure in which the inner surface is made of stainless steel material and the outer surface is made of SS41 in consideration of corrosion resistance and the like, and is made of urethane board or the like between both materials. Cooling materials are provided. Normally, the thickness of the cooling material is about 20 mm, the thickness of the inner surface material is about 1.2 mm, and the thickness of the outer surface material is about 9 mm. This configuration reduces the cost because the inner stainless material is thin, and the inner surface material (stainless material) only needs to be fitted inside the cold insulating material, so that the manufacturing is easy and the heat shrinkage can be achieved. This is because it has an advantage. However, it may be a double structure made of other materials.

Here, in the drawing, the food freezing tank 1 has a laterally long container shape whose upper part in the left-right direction spreads outward, and has the cooling coil 6 and the stirring blades 7 ′ of the stirrer 7 on the inner bottom part. Have Two cooling coils 6 are arranged vertically in parallel from the front wall 9 side, and a stirring blade 7'is arranged on the rear wall 10 side. The stirring blade 7 '
The main body of the stirrer 7 for driving is installed in a space 11 formed by the food freezing tank 1 and the apparatus main body 5 with a flexible material interposed in consideration of vibration prevention and thermal expansion.

The freezing food transfer section 2 is composed of a freezing food transfer conveyor 12 and a pressing conveyor 13. The freezing food transfer conveyor 12 is formed of a steel net conveyor with fins, and its food transfer surface 12 '. A pressing conveyor 13 made of a steel net conveyor is disposed at a position corresponding to.
The frozen food transport conveyor 12 is formed with a frozen food supply unit 14 for supplying frozen food on the left side in the drawing,
A frozen food takeout part 15 for taking out frozen food is formed on the right side in the drawing, and the food freezing part is immersed in the freezing liquid filled in the food freezing tank 1 at the center.
16 are formed. And the food transport conveyor for freezing
12 frozen food supply unit 14 and frozen food take-out unit 15
The food freezing tank 1 is arranged so as to be located at the upper portions of the front wall 9 and the rear wall 10, respectively. Here, the frozen food transport conveyor 12 is a drive device installed in the space 11.
It is driven by 17. Further, the pressing conveyer 13 is arranged so as to face the food conveying surface 12 'of the freezing food conveying conveyer 12 as described above, and frozen food can be sandwiched between the freezing food conveying conveyer 12 and frozen. The freezing food is soaked in the freezing liquid at the center of the food conveying conveyor 12. In addition, at the left and right ends of the upper wall forming the apparatus body 5, the frozen food is taken out from a frozen food feeding section 14 of the frozen food conveying conveyor 12 and a frozen food taking-out section 15 for supplying the frozen food to the frozen food. And a lid for.

The freezing liquid jetting parts 3 are respectively arranged above and below the food carrying surface 12 ′ of the freezing food carrying conveyor 12. The freezing liquid spraying unit 3 is formed of a pipe 19 having a plurality of spraying nozzles 18 for spraying the freezing liquid onto the frozen food, and the pipe 19 is installed in the space 11. It is connected to the food freezing tank 1 via a pump 20 so that the freezing liquid in the food freezing tank 1 can be supplied. Here, an injection nozzle that forms the freezing liquid injection unit 3
18 is arranged all over the center of the frozen food transport conveyor 12 immersed in the freezing liquid so that it can be sprayed evenly on the frozen food to be transported. And usually the injection nozzle
The injection amount of the refrigerating liquid injected from 18 can be adjusted by a valve (not shown) or the like.

The liquid-resistant packaging material transfer unit 4 includes liquid-resistant packaging material feeding rollers 22 and 22 for feeding the liquid-resistant packaging materials 21 and 21 made of upper and lower strip-shaped (continuous) vinyl sheets and the like and the liquid-resistant packaging. Material take-out roller 23 and heat-sealed portion 24 for sealing liquid-resistant packaging material
And consists of. Liquid-resistant packaging material delivery rollers 22, 22, provided in the frozen food supply unit 14 of the frozen food transport conveyor 12,
It is arranged so as to polymerize in a heat-welding section (24) for sealing a liquid-resistant packaging material, which is arranged in a contact section (25) between a freezing food conveying conveyor (12) and a pressing conveyor (13). The liquid-resistant packaging material sealing heat-welding part 24 is a right angle iron 25 for heat-sealing the liquid-resistant packaging materials 21, 21 in a direction perpendicular to the traveling direction of the liquid-resistant packaging materials 21, 21. The liquid-resistant packaging materials (21) and (21) are configured with both-side irons (26) for continuously heat-sealing both sides in the traveling direction. Further, the liquid-resistant packaging material take-out roller 23 is
It is arranged in the frozen food take-out section 15 of the frozen food transport conveyor 12.

A floating plate 27 is formed of a cold insulating material or the like, and is floated on the liquid level of the freezing liquid filled in the food freezing tank 1. Here, the floating plate 27 does not have to have a completely floating structure, and may have a hanging structure or the like. In other words, for example, it may move up and down along the liquid surface.

Next, an example of the method of the present invention will be described using the food freezing apparatus having the above-mentioned configuration.

First, the food freezing tank 1 is filled with an antifreeze liquid (freezing liquid) such as a propylene glycol aqueous solution or an alcohol aqueous solution, and the floating plate 4 is placed on the liquid surface, and then the tank 1
A cooling medium is supplied to the cooling coil 6 installed in the tank to cool the freezing liquid, and the stirring blade 7'is driven by the stirrer 7 to stir and cool the freezing liquid in the tank 1 to obtain a uniform temperature. To hold.

And, in the above state, the frozen food transport conveyor
Drive 12 and insert liquid-resistant packaging materials 21, 21 such as two vinyl sheets from liquid-resistant packaging material delivery rollers 22, 22 between freezing food transport conveyor 12 and pressing conveyor 13, and the tip portion thereof. After being guided to the liquid-resistant packaging material take-out roller 23, the liquid-resistant packaging materials 21 and 21 are welded in a direction perpendicular to the traveling direction by the right angle iron 25 of the heat-resistant portion 24 for sealing the liquid-resistant packaging material. To do.
Then, the frozen food is supplied to the frozen food supply section of the conveyor 12.
The liquid-resistant packaging materials 21 and 21 are sequentially supplied from 14 to surround the frozen food with the liquid-resistant packaging materials 21 and 21 (enclosed so as to be packed from above and below. Here, the fin portion of the conveyor 12 and the pressing conveyor are surrounded. Then, both sides of the liquid-resistant packaging materials 21, 21 in the traveling direction are continuously heat-welded by the irons 26 on both sides of the heat-welding portion 24 for sealing the liquid-resistant packaging material, and the freezing is performed. The food is frozen by the fins of the freezing food transporting conveyor (12), sandwiched between the two conveyors (12, 13), and transported by the freezing food transporting conveyor (12) to the food freezing section (16). Here, the refrigerating liquid is substantially evenly distributed on the liquid-resistant packaging materials 21, 21 from a plurality of injection nozzles 18 forming the freezing liquid ejecting section 3 arranged at the upper and lower positions of the freezing food transport conveyor 12. It is sprayed so that it can be frozen evenly for frozen items.

Further, the air between the liquid-resistant packaging materials 21, 21 is discharged to the rear opening side, that is, the frozen food supply section 14 side by the liquid pressure of the cooling liquid in the tank 1, and therefore, the liquid-resistant packaging material 21 ,
The frozen food between 21 and the liquid-resistant packaging material 21, 21 will be in close contact with each other, and will be in the same state as when vacuum packed (there is no cooling effect because there is no air layer). . Here, there is some effect of making the sealed state even by the injection pressure of the freezing liquid. However, it need not be.

Further, heat of the frozen food is taken by the freezing liquid and the injection freezing liquid in the food freezing tank 1 in the food freezing section 16, and the frozen food is frozen.

Then, the frozen frozen food is conveyed by the freezing food transport conveyor 12 in the direction of the frozen food take-out section 15, and the backwashing high-pressure air nozzle 28 disposed at the frozen food take-out section 28.
After backwashing the freezing liquid attached to the liquid-resistant packaging materials 21, 21, the liquid-resistant packaging materials 21, 21 are cut (opened), and the frozen food can be taken out from the frozen food take-out section 15. I am trying.

By the way, in the above-mentioned embodiment, the freezing liquid injection unit is described in the configuration arranged at the upper and lower positions of the food transport conveyor for freezing, but the configuration is not limited to this configuration, and for example, it is arranged on either one side. You may use the thing of the provided structure. Further, the refrigerating liquid to be supplied to the refrigerating liquid ejecting unit is configured such that a separate refrigerating liquid is obtained from another tank or the like without taking a means of utilizing the refrigerating liquid in the tank via a pump. Alternatively, a configuration may be adopted in which the refrigerating liquid injection unit is not provided.

Further, in the above-described embodiments, the freezing liquid is used as the refrigerant to be sprayed onto the frozen food through the liquid-resistant packaging material, but it is obvious that a freezing gas may be used. Further, the injection of the refrigerant may be performed not at a portion corresponding to the food freezing portion of the food freezing tank but at a contact portion between the freezing food transport conveyor and the pressing member.

Furthermore, in the above-described examples, the liquid-resistant packaging material was described as a configuration using a liquid-resistant packaging material composed of upper and lower two strip-shaped vinyl sheets, but a tubular liquid-resistant packaging material or Alternatively, a liquid-resistant packaging material or the like configured by folding one sheet on one side in the traveling direction may be used. In this case, the number of sealing points can be reduced.

It should be noted that the present invention is not limited to the above-described embodiments, but includes modifications that can be implemented without departing from the scope of the present invention.

〔The invention's effect〕

As is clear from the above description, according to the food freezing method of the present invention, a liquid-resistant packaging material inserted between the freezing food transport conveyor and the pressing member, in parallel with the driving of the freezing food transport conveyor. Surrounding frozen food (covering or packaging)
Therefore, it is not necessary to pack the frozen food in the packaging material in advance at the time of freezing, so that the workability can be improved.

Further, in the food freezing method of the present invention, when both different means of the freezing liquid in the food freezing tank and the injection liquid / injection gas (refrigerant) are used, there are large variations in freezing of the frozen food. This has the effect that the occurrence of

Further, according to the food freezing method of the present invention, the air remaining between the liquid-resistant packaging material and the frozen food is discharged to the outside by the liquid pressure of the freezing liquid from the outside of the liquid-resistant packaging material. Therefore, there is an effect that the frozen food can be frozen in a substantially sealed pack with a liquid-resistant packaging material.

Therefore, according to the food freezing method of the present invention, when the frozen food is frozen, the presence of the air layer between the frozen food and the liquid-resistant packaging material is reduced, so that the frozen food is thawed. It is possible to reduce the amount of drip generated and to obtain a frozen food having a good commercial value.

[Brief description of drawings]

1 and 2 show an embodiment of a food freezing apparatus used for embodying the method of the present invention, and FIG. 1 is a schematic vertical sectional view,
1 is a partially enlarged view of FIG. 1, FIG. 3 is a schematic sectional view taken along line AA of FIG. 1, and FIG. 4 is a schematic vertical sectional view of a conventional device. 1 ... Food freezing tank, 2 ... Freezing food transport section, 3
...... Refrigerating liquid jetting unit, 4 ...... Liquid-resistant packaging material transfer unit, 12 ...
… Frozen food transport conveyor, 13 …… Pressing conveyor (pressing member), 14 …… Frozen food supply section, 15 …… Frozen food takeout section, 16 …… Food freezing section, 18 …… Injection nozzle, 24
...... Heat-welded part for sealing liquid-resistant packaging material, 25 ...... Contact part between food transport conveyor for freezing and pressing conveyor

Claims (4)

(57) [Claims] 1. A food transporting conveyor for freezing, which is arranged in a food freezing tank so that at least a part thereof is immersed in a freezing liquid in the tank for freezing food, and a food conveying conveyor for freezing, which is arranged above the food carrying conveyor for freezing. The frozen food is surrounded by a liquid-resistant packaging material that is interposed between the liquid-resistant packaging material and a pressing member such as a pressing conveyor, and the opening of the liquid-resistant packaging material excluding the rear end in the traveling direction is sealed, and Air between the liquid-resistant packaging material and the food for freezing is discharged to the outside by hydraulic pressure by the liquid for freezing to keep the frozen food in a sealed state, and the food for freezing is put through the liquid-resistant packaging material. The food freezing method is characterized in that the food is frozen while being transported by a freezing food transport conveyor. 2. A means for discharging air between the liquid-resistant packaging material and the frozen food to the outside to keep the frozen food in a sealed state is a liquid pressure by the freezing liquid and a liquid-resistant packaging material. The food freezing method according to claim 1, wherein the food freezing method is carried out by means of an injection pressure of the refrigerant by injecting a refrigerant such as a freezing liquid or a freezing gas into the frozen food via the. 3. The food freezing method according to claim 1, wherein the liquid-resistant packaging material comprises two upper and lower vinyl sheets or a single vinyl sheet having one side folded in the traveling direction. 4. The food according to claim 2, wherein the freezing liquid filled in the food freezing tank is circulated by a pump and used as the freezing liquid to be sprayed onto the frozen food. Freezing method.