JPH02110272A - Continuous quick freezing device for food - Google Patents

Abstract

PURPOSE:To hold air around foods to be frozen in the condition of no air flow to prevent the foods from being dried and restrain the change of concentration of salts in the solution of the foods to be frozen by a method wherein a transfer means such as a super low-temperature steel belt and the like and a super low-temperature radiating means are combined. CONSTITUTION:When a driving roll 7 is started for turning, an endless belt type transfer means 3 is slid and moved from an inlet port 5 toward an outlet port 6 smoothly while contacting to a flat surface on a cooling plate 13 without leaving any gap therebetween. Accordingly, the transfer means 3 is cooled suddenly by the cooling plate 13 and the temperature thereof becomes a desired value at least at the vicinity of the inlet port 5 before the same. Next, foods 1 to be frozen, transferred by the belt 11 of a material working process, drop onto the transfer means 3 to transfer them into a freezing box 2 whereby the foods are frozen from a contacting surface between the transfer means 3. On the other hand, heat is deprived from the circumference of the foods in the condition of no wind by a low-temperature radiating means 4 provided in the freezing box 2 whereby the surface temperature of the foods 1 is reduced quickly and the foods are frozen. The frozen foods 1 to be frozen are transferred on the transfer means 3 to drop them onto the belt 12 of packing work process while the process is advanced to a next process to produce desired products.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a continuous quick-freezing device for foodstuffs, and more particularly to a continuous quick-freezing device for foodstuffs having low-temperature radiating means.

[Prior Art] A conventional freezing device is of a type in which an endless belt for conveying a metal tray is installed on a copper plate having a cooling means such as a cooling coil. There is also a type that combines an endless steel belt with cooling means and a blower type cooler, but in the former type, a metal tray is moved over a copper plate, so the copper plate is exposed to air. Moisture was adhered to the entire surface in the form of powder snow, which caused a reduction in the freezing efficiency of the frozen object due to thermal resistance.
Since the items to be frozen can only be transported after being aligned on the metal tray, de-plating is required even after freezing, making automation unusable, making the system extremely unreasonable from a labor-saving perspective. Furthermore, from a quality standpoint, the frozen material stagnates before and after the freezer, causing contamination due to temperature rise.

On the other hand, the latter type of freezing method uses heat conduction and convection heat transfer, so the air flow velocity hitting the frozen object is high, and furthermore, there is a temperature difference between the air at the entrance and exit of the refrigeration equipment and the air at the center of the equipment. It accelerates the drying of the frozen material and also promotes the oxidation reaction. For example, myoglobin and hemoglobin contained in the flesh of meat, tuna, etc. become metmyoglobin, which causes the deterioration in color to dark red or brown.

[Problem to be solved by the invention]

In view of the above circumstances, this invention places objects to be frozen on a cooled endless steel belt or the like serving as a conveying means, freezes them from the lower surface by heat conduction, and uses airless low-temperature radiation means to freeze the objects. This was done based on the fact that if the ambient air temperature is cooled to below the temperature of the top surface of the conveying means, it will be possible to freeze the entire surrounding area, which will be extremely useful in preventing oxidation and deterioration of the material to be frozen. .

Therefore, the main object of the present invention is to provide a continuous quick-freezing device for food products that can produce high-quality products that do not cause discoloration, deterioration, or drying of frozen objects.

Another object of the present invention is to enable food products to pass through the temperature range of -4 to -7°C, such as discoloration and deterioration of meat, tuna, etc., in a few minutes, thereby minimizing the effects of such changes. The objective is to provide freezing equipment.

Still another object of the present invention is to provide a continuous quick-freezing device for food products that can minimize drying of frozen items such as meat and tuna by obtaining low temperatures without wind using low-temperature radiation means. It is.

Still another object of the present invention is to provide a continuous rapid freezing device for food products that has a compact structure that does not require any special structure or materials, and that can be easily manufactured.

[Means to solve the problem]

In order to achieve the above object, the present invention comprises a conveying means for placing an object to be frozen, a cooling means, and a low-temperature radiation means, and the conveying means is cooled while sliding on the cooling means,
The object to be frozen is frozen by the contact surface of the conveyance means and the low temperature radiation means.

[Effect]

Since the conveying means and the cooling means are combined with a low-temperature radiation means, the air around the frozen object can be kept at a temperature lower than the top surface of the conveying means in a windless state, thereby preventing oxidation and deterioration of the frozen object. Freezing can be done while preventing such things.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 and FIG. 2 are a perspective view and a vertical cross-sectional view showing an embodiment of the continuous quick freezing device for foodstuffs according to the present invention. The freezing box ( 2), a transport means (3) for placing the object to be frozen (1), a cooling means for cooling the transport means (3), and a low temperature radiation means (4).

The freezing box (2) contains the population (5) of the object to be frozen (1).
and an outlet (6) are formed, and a conveying means (3), a cooling means and a low temperature radiation means (4) are provided between the population (5) and the outlet (6). Further, a driving roll (7) and a driven roll (8) are arranged outside the entrance (5) and the exit (6), respectively, and a freezing box (2)
A guide roll (9) is arranged inside. These rolls (7), (8), and (9) are configured so that a conveying means (3), which will be described later, is wound around them. Furthermore, the drive roll (7) is configured to be driven by a variable speed motor (10).

Note that (11) is a belt for the raw material processing process, and (12) is a belt for the packaging process.

The conveying means (3) is made of an endless steel belt or the like, and is configured to be wound by each roll (7), (8), and (9) indicated by -F.

Although it is preferable to use a steel belt as the conveying means (3), it is also possible to use a non-metallic material such as a synthetic resin film.

The cooling means is a metal having a smooth surface on one side, and is provided so that the conveying means (3) can slide on the cooling means.
a cooling plate (13) made of a material with good heat conductivity such as an alloy;
It consists of piping (14) arranged on a cooling plate (13), and depending on the set temperature range, refrigerant such as fluorocarbon gas,
It is configured to allow antifreeze or liquefied gas to flow through the pipe (14).

For example, if the set temperature range is -50 to -70°C, fluorocarbon gas or the like is used, and if the set temperature range is -70 to -100°C, liquid nitrogen or the like is used. Moreover, when using antifreeze or liquefied gas, a chamber may be provided instead of the piping (14).

Note that the refrigerant and the like are cooled by a separate device (not shown).

As shown in FIG. 3, the low-temperature radiating means (4) is a metal plate (15), and a cooling pipe (16) is installed in the cooling pipe (16). (B
), and the method for cooling the low-temperature radiant means (4) is to cool the metal plate (15).
In addition to the method of installing a cooling pipe (16) in the cooling pipe (16), various methods can be considered, such as forming a refrigerant path in the metal plate (15) and flowing the refrigerant. Furthermore, low temperature radiation means (4
) is constructed in such a way that the gap between the cryogenic radiation means (4) and the conveying means (3) can be adjusted or fixed at a desired position.

Note that the refrigerant and the like are cooled by a separate W (not shown).

Next, the usage conditions of the continuous rapid freezing device for foodstuffs of the present invention will be explained.

First, when the drive roll (7) is rotated, the endless belt-like conveying means (3) moves from the inlet (5) to the outlet (6).
The cooling plate (13) comes into contact with the smooth upper surface of the cooling plate (13) without any gaps, and slides smoothly. Therefore, the conveying means (3) is strongly cooled by the cooling plate (13) and reaches the desired temperature at least in the vicinity in front of the inlet (5).

Next, the object to be frozen (1) transported by the belt (11) in the raw material processing step falls onto the transport means (3), is transported into the freezing box (2), and comes into contact with the transport means (3). In addition to being frozen from the surface, the low-temperature radiation means (4) installed in the freezing box (2) also removes heat from the surrounding area without wind, rapidly lowering the surface temperature of the frozen object (1) and freezing it. be done.

The frozen object (1) is further transferred to a conveying means (3).
(12) It falls onto the top and proceeds to the next process to become a product.

By the way, the object to be frozen (1) placed i1 on the conveying means (3) does not adhere to the conveying means (3) during freezing.The reason for this is unknown, but when the conveying means (3) The object to be frozen (1) is cooled to below a certain temperature 6, and the object to be frozen (1)
), therefore, after passing through the driven roll (8), the frozen object (1) easily falls from the conveying means (3) and onto the bell I-(12) of the packaging process. .

Furthermore, even if the frozen object (1) were to adhere to the conveying means (3), the conveying means (3) would curve along the driven rolls (8), so the frozen object (1) could easily be attached to the conveying means (3). (3) It peels off and falls off.

Here, to explain the mechanism of deterioration in the quality of the material to be frozen (1), such as discoloration of meat, etc., the myoglobin contained in beef cattle, which is normally reddish-purple, becomes oxymyoglobin due to the state in which oxygen is lightly bound. The color of the flesh changes to bright red. Furthermore, when oxygen is strongly bound, that is, oxidized, oxymyoglobin changes to metmyoglobin, and Fe in the molecules contained in beef cattle changes from divalent to trivalent.
It changes in color and takes on a brown color. The degree of this brownness is 50%
If the temperature is exceeded, the color of the meat will turn brown.

The mechanism by which myoglobin changes into metmyoglobin, that is, the influencing factor of oxidation, is that the freezing Th (1
) (7) Temperature, Pl, M elemental partial pressure, salt! f degrees, light rays, etc. Therefore, if these influencing factors are controlled to a minimum, it is possible to minimize discoloration of meat, etc.

Therefore, when the food item (1) to be frozen, such as meat, is frozen using the continuous rapid freezing apparatus for foodstuffs of the present invention having the above-mentioned configuration, the item to be frozen (1) does not dry out, so the meat, etc. There is no increase in the salt concentration, the pH is low, and the ultra-low temperature and airless conditions make it possible to produce high-quality products that will not oxidize.

〔Effect of the invention〕

As is clear from the above description, the continuous rapid freezing device for foodstuffs of the present invention combines a conveying means (3) such as an ultra-low temperature steel belt and a low temperature radiation means (4) to 1) The entire surrounding air is cooled by low temperature radiation means (
4), the object to be frozen (1) is kept at an ultra-low temperature in a windless state, and the surface temperature of the object to be frozen (1) can be rapidly lowered by absorbing heat from the object to be frozen (1).
Freezing progresses from the beginning, and at the same time, freezing progresses from the entire surrounding area as well.

Therefore, unlike conventional refrigeration equipment equipped with a blower, it maintains an ultra-low temperature state with no wind and does not dehumidify, preventing the product from drying out and minimizing changes in the salt concentration in the aqueous solution of the object to be frozen (1). It is possible to suppress oxidation reactions as well as suppress decomposition reactions by microorganisms, making it possible to produce high-quality frozen products, such as the production of clean, bright red frozen meat products.

Furthermore, since the continuous rapid freezing device for food products of the present invention combines the conveying means (3) and the low temperature radiation means (4), it has a compact structure and does not use any special structure or materials. It has the excellent effect of being easy to manufacture.

[Brief explanation of the drawing]

1 to 3 show an embodiment of the continuous quick freezing device for food products of the present invention, FIG. 1 is a perspective view showing the overall structure, and FIG. 2 is a sectional view of the same side. , FIG. 3 is an explanatory diagram of the low temperature radiation means. (1)...Object to be frozen (3)...Transportation means (4)
...Low temperature radiation means

Claims (1)

[Claims] 1. The object to be frozen is composed of a conveyance means for placing the object to be frozen, a cooling means, and a low-temperature radiation means, and the conveyance means is cooled while sliding over the cooling means, and the object to be frozen is conveyed. 1. A continuous rapid freezing device for food products, characterized in that foods are frozen by a contact surface of the means and a low temperature radiation means. 2. The continuous quick-freezing device for foodstuffs according to claim 1, wherein the conveying means is an endless steel belt or the like. 3. The continuous quick-freezing device for foodstuffs according to claim 1 or 2, wherein the cooling heat source of the cooling means is brine. 4. The continuous rapid freezing device for foodstuffs according to claim 1, wherein the low temperature radiation means is a metal plate having cooling means. 5. The continuous rapid freezing device for foodstuffs according to claim 1 or 4, wherein the gap between the low temperature radiation means and the object to be frozen can be adjusted.