JP3567987B2 - Manufacturing method of sterilized ice - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for producing a large amount of sterilized ice using acidic water containing chloride ions.
[0002]
[Prior art]
Generally, when transporting caught seafood to a market in a fishing port, in order to maintain freshness, the fish and shellfish are packed in ice in containers and hold and transported. Further, when transported by truck from a fishing port market to a consumption area, or when stored at a fish shop, restaurant, food processing factory, etc., freshness is maintained by filling with ice.
[0003]
However, generally used ice is ice made from neutral water with a pH of about 7, and the purpose is to keep fish and shellfish at an ice temperature of about 0 ° C until the ice melts, with the aim of suppressing bacterial growth. I have. This cooling by ice does not sterilize the bacteria attached to the fish and shellfish, but only makes the activity of the bacteria dormant.As the temperature of the fish and shellfish increases, the bacteria grow rapidly. is there.
[0004]
In recent years, the use of more acidic water such as electrolysis for sterilization is performed. This is to kill bacteria attached to the surface of the seafood by washing the surface with acidic water. However, when the acidic water comes into contact with the proteins and fats of the fish and shellfish, the chlorine ion concentration is sharply reduced and the sterilizing effect is lost. Therefore, it is necessary to sterilize the acidic water while flowing the acidic water. In addition, this sterilization method requires a facility for producing acidic water and is costly. In addition, since it is used in flowing water, large-scale facilities are required for producing a large amount of acidic water.
[0005]
Therefore, an ice for preserving fresh food containing hypochlorous acid, which is unstable and rapidly decomposes by freezing an aqueous solution containing hypochlorous acid and confining the solution in ice, has been proposed (International Publication Number WO00 /). 088956). This fresh food preservation ice has a hypochlorous acid content (chlorine ion concentration) of 5 to 30 ppm, and in addition to a preservation effect at an ice temperature in a state of directly contacting the fresh food, the ice Even if is dissolved, food can be safely stored for a long time by the sterilizing power of hypochlorous acid in ice.
[0006]
However, in this method, acidic water having a pH of about 6 produced by an electrolyzed water producing apparatus is sent to a small ice maker, where small ice cubes each having a size of about 3 cm are continuously produced. In addition, there is a problem in that two expensive devices such as ice making devices are required, and mass production is not possible. In addition, this proposal was made in a laboratory, and in a normal ice making device, water is jetted to make the ice transparent, or ice is made while sending air, and bubbling is performed. unstable hypochlorous acid will be released almost to the atmosphere, the ice and the ice-making by a method as described in the specification hypochlorite is not only slightly remaining, also large blocks When ice was made, the problem that the residual chlorine ion concentration became non-uniform was confirmed.
[0007]
[Problems to be solved by the invention]
The present invention solves the above-mentioned problems, uses an apparatus for making a large amount of ice in an ice-making factory, lowers the production cost, uniformly and reliably seals unstable hypochlorous acid in the ice, and melts the ice. An object of the present invention is to provide a method for producing sterilized ice, which can maintain a sterilizing effect for a long time and keep foods fresh.
[0008]
[Means for Solving the Problems]
In the method for producing sterilized ice according to claim 1 of the present invention, a mixed solution obtained by adding an acid such as hydrochloric acid or acetic acid and sodium hypochlorite to neutral water is placed in an ice making frame. Into the ice making pool where the antifreeze chilled below the freezing point circulates, and the mixture is allowed to make ice in a stationary state. The mixture is intermittently stirred to make milky white ice while the concentration of the mixed solution is slowly made uniform, and the obtained block-shaped sterilized ice is crushed with a crusher.
[0009]
In the method for producing sterilized ice according to claim 2 of the present invention, as a stirring method, a water-absorbing hose of a pump is inserted into a bottom side of a non-frozen mixed liquid pool, and a drain hose is inserted into an upper side of the mixed liquid pool. to the mixture in the form close to a stationary state by intermittently agitated by a pump, it is characterized in the this to convection while pulling up the water hose so as not confined to the freezing unit.
[0010]
Hereinafter, the method for producing sterilized ice of the present invention will be described in detail. The mixed solution is prepared by adding an acid such as hydrochloric acid or acetic acid and sodium hypochlorite to neutral water. In this case, when the acid and sodium hypochlorite are added, they are mixed with water so that the reaction does not proceed. The concentration of the mixture is adjusted so that the chloride ion concentration is 8 to 200 ppm and the pH is 3.5 to 5.5.
[0011]
Next, as shown in FIG. 1, the mixture 1 is poured into an ice making frame 2. Alternatively, water, an acid, and sodium hypochlorite may be separately poured into the ice making frame 2 to form a mixed solution. The ice making frame 2 is a large-sized one used in a normal ice making factory, for example, for 90 kg or 135 kg. Next, the ice making frame 2 into which the mixed liquid 1 has been poured is immersed in an ice making pool 4 in which an antifreeze 3 cooled to about 15 ° C. below zero is circulated as shown in FIG. . Since the ice making frame 2 is formed of a metal plate, it has good thermal conductivity, is rapidly cooled from the surface side of the ice making frame 2, and after two to three hours as shown in FIGS. Freeze to a thickness of about 4-5 cm.
[0012]
During the freezing process, the freezing portion 5 is milky white because the freezing portion 5 is frozen while discharging dissolved oxygen and chlorine gas, and is sealed as fine bubbles. A mixed liquid reservoir 6 is formed in a central portion inside the freezing portion 5. Normally, when making ice in an ice making factory, transparent block ice is made by removing dissolved oxygen by sending air to the water poured into the ice making frame 2 and freezing while bubbling. When bubbling, sodium hypochlorite reacts with the acid to generate chlorine, which is released into the air, so in the present invention, it is not possible to freeze in a stationary state and confine hypochlorous acid in ice. .
[0013]
When the ice freezes down to about 4-5 cm in thickness along the side of the frame, the heat conductivity of the ice is low, so that it takes time for the heat of the mixed liquid pool 6 to be transferred to the antifreeze 3. Become. In such a state, the mixed liquid 1 in the mixed liquid pool 6 has a heavy solution sinking down. If it is allowed to stand still and frozen in a state where there is a difference in concentration, a frozen portion 5 having a transparent upper portion and a low chloride ion concentration is formed, and a non-uniform block-shaped ice 10 is formed as a whole.
[0014]
For this reason, when the mixed liquid reservoir 6 is formed at the center, as shown in FIG. 5, the water absorption hose 8 of the pump 7 is inserted into the bottom of the mixed liquid reservoir 6, and the drainage hose 9 is inserted into the upper portion, thereby obtaining a specific gravity. The heavy mixed solution 1 is sucked up, gently sent to the upper portion, and then convected to homogenize the concentration and freeze.
[0015]
In addition, when constantly stirred and convected by the pump 7, the hypochlorous acid reacts with the acid to generate chlorine gas, the bubbles are scattered in the atmosphere, the effective hypochlorous acid is reduced, and the inside of the factory is reduced. It is performed intermittently because the work environment may be deteriorated. Therefore, it is necessary that the convection by the pump 7 be performed intermittently every several hours, for several minutes to several tens of minutes, to stir as much as possible in a stationary state, and to make the concentration slowly uniform.
[0016]
As described above, when the concentration of the mixed liquid reservoir 6 is made uniform, the operation of the pump 7 is stopped, and the freezing is allowed to proceed in a state where the mixed liquid reservoir 6 is allowed to stand still, as shown in FIG. It is becoming. For this reason, the water absorption hose 8 and the drainage hose 9 are pulled up little by little so as not to be trapped in the freezing section 5, the pump 7 is operated every several hours, and finally pulled out, as shown in FIG. To manufacture.
[0017]
When the block-shaped ice 10 as shown in FIG. 7 is manufactured in this manner, the ice making frame 2 is pulled up from the ice making pool 4, taken out of the ice making frame 2 and crushed by a crusher to finely break the ice. Although the chlorine ion concentration varies depending on the portion of the manufactured block-shaped ice 10, the chlorine ion concentration is averaged by crushing ice. The crushed ice is shipped and used for refrigeration of fish and the like.
[0018]
The crushed ice was mixed with ice of various sizes and snow-like ice by crushing ice, so the contact area with food increased and the food was efficiently brought to the ice temperature state. Can be cooled. Furthermore, as in the case of crushed ice commonly used for ice-packing fish, it can be easily transported and stored, and can be put into a foaming container containing fish using a scoop or the like.
[0019]
For example, when crushed sterilized ice is put into a foamed plastic container for storing fish and stored and transported, the growth of bacteria can be suppressed by the ice temperature effect of the sterilized ice. In addition, acid water with low pH gradually melts out over time and comes into contact with food and food containers, so that bacteria adhering to the surface can be sterilized in a short time and chloride ions can be removed. Since the state of unstable activity is maintained, rapid growth of bacteria can be prevented even when the temperature rises, and freshness can be favorably maintained for a long time. In addition, since chlorine ions are kept in an unstable state in acidic water, when they come into contact with proteins and fats, they are scattered as chlorine gas, so that the food has no chlorine odor and is safe to eat.
[0020]
In the present invention, the concentration of chloride ions contained in the mixed solution 1 is specified in the range of 8 to 200 ppm. If the concentration is less than 8 ppm, the chlorine ions are reduced in the ice making process, and the concentration of chlorine ions becomes less than 5 ppm in the state of ice and sterilization. If the effect is reduced, and if the amount of the mixed solution 1 exceeds 200 ppm, chlorine ions remaining in the ice become 180 ppm or more, the chlorine odor becomes strong in a state where the ice is melted, the odor remains in the food, and the flavor of the food is impaired. Because it is
[0021]
The mixed solution 1 of the present invention uses acidic water having a pH of 3.5 to 5.5. This acidic water is characterized by a quick-acting effect of disinfecting in a short time with a shock, and the pH of the mixed solution 1 is not changed much even by disinfecting ice. By using acidic water having a pH of less than 5.5, chloride ions can be kept in an unstable state. In other words, chloride ions become unstable in acidic water, contact bacteria and sterilize them quickly, and gasification easily releases chlorine odor, and proteins and fats in the fish dissolve in the solution. PH rises to neutral water. If the pH is less than 3.5, chloride ions are hardly activated, and a large amount of hydrochloric acid or acetic acid must be used, which is not economical.
[0022]
【Example】
Sodium hypochlorite solution and acetic acid were respectively added to neutral water to prepare a mixed solution of pH 4.5 containing 50 ppm of chloride ions. Next, the mixed solution 1 was poured into an ice making frame 2 for 90 kg, and then the ice making frame 2 was immersed in an ice making pool 4 in which an antifreeze solution 3 cooled to about 15 ° C. below zero was circulated. Cool with.
[0023]
The mixed solution 1 was rapidly cooled from the surface side of the ice making frame 2 and, after 3 hours, was frozen to milky white having a thickness of about 4 to 5 cm along the side surface of the frame. In this state, the water-absorbing hose 8 of the pump 7 is inserted into the bottom of the mixed liquid reservoir 6 and the drain hose 9 is inserted into the upper part of the mixed liquid reservoir 6 formed in the central portion. And slowly gently convey it to the top and convection for 10 minutes to slowly homogenize the concentration and freeze.
[0024]
As described above, when the concentration of the mixed liquid reservoir 6 is made uniform, the operation of the pump 7 is stopped, and the freezing of the mixed liquid reservoir 6 gradually becomes smaller as the freezing proceeds while the pump 7 is left standing. Thereafter, the mixed solution 1 in the mixed solution pool 6 was convected by the pump 7 every 3 hours for 10 minutes, and after 12 hours, the whole became milky and was completely frozen.
[0025]
Thereafter, the ice making frame 2 was pulled out of the ice making pool 4 to take out a block-like ice 10 having a length of 18 cm, a width of 57 cm and a height of 82 cm as shown in FIG. This ice 10 is milky white as a whole. A 25 cm portion of ice 10A from the top is cut out into a flat plate having a thickness of 3 cm, and a 53 cm portion from the top is cut out from ice 10B into a flat plate having a thickness of 3 cm. The chloride ion concentration was measured.
[0026]
As a result, the result of measurement of the chloride ion concentration of each part of the ice 10A cut out from the upper side by the KI method is as shown in FIG. 9. On the average, the chlorine ion concentration of the upper side ice 10A is 23 ppm, and the lower side is 10 ppm. Ice 10B was 43 ppm. Thereafter, the block-shaped ice 10 was crushed by a crusher and finely crushed. The crushed ice was mixed with ice of various sizes and snow-like ice. The crushed ice had a lower chloride ion concentration than the block ice 10, and the average chlorine ion concentration was 32 ppm.
[0027]
For comparison, when ice was made while sending air and bubbling in the same manner as in the normal ice making process, transparent ice 10 was produced, and almost no chlorine ions were detected. Further, when ice was produced while the mixed solution reservoir 6 was allowed to stand without stirring, the upper half became transparent, and ice having a non-uniform chloride ion concentration was obtained.
[0028]
Note in the above description shows the case where stirring by 10 minutes per mixing liquid reservoir 6 with pump 7 3 hours but this interval and stirring time as possible out be selected arbitrarily.
[0029]
【The invention's effect】
As described above, according to the method for producing sterilized ice according to claim 1 of the present invention, a mixed solution containing an acid and sodium hypochlorite is poured into an ice making frame, and the antifreeze is cooled below freezing. Is immersed in a circulating ice-making pool, and the mixture is allowed to make ice in a stationary state.In the ice-making process, the mixed liquid pool in the central part that is not frozen is intermittently stirred in a form close to the stationary state, Mild-white ice is produced while the concentration of the mixed solution is slowly homogenized, and the obtained block-shaped sterilized ice is crushed with a crusher to produce a large amount of sterilized ice having a substantially uniform chloride ion concentration, and the price is the same as before. It is almost the same as ice and can be manufactured at low cost, and can exert a great effect on maintaining freshness during transportation and storage of fresh food such as fish.
[0030]
According to the method for producing sterilized ice according to claim 2, the mixed liquid in the mixed liquid pool is intermittently stirred in a form close to a stationary state, and is convected while pulling up the water-absorbing hose. The pump can be prevented from being closed, and a small and inexpensive pump is sufficient. The lifting mechanism and timer can be easily set, which is suitable for automatic ice making.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view illustrating a method for producing sterilized ice according to an embodiment of the present invention, showing a state where a mixed solution is poured into an ice making frame.
FIG. 2 is a cross-sectional view showing a state in which an ice making frame to which a mixed solution has been injected is immersed in an ice making pool.
FIG. 3 is a cross-sectional view showing a state where the ice making frame is frozen from the inside of the side surface.
FIG. 4 is a plan view showing a state where the ice making frame of FIG. 3 is frozen from the inside of the side surface.
FIG. 5 is a cross-sectional view showing a state in which a pump is inserted into a liquid mixture reservoir and stirring is performed.
FIG. 6 is a cross-sectional view showing a state in which the pump is raised to stir the mixed liquid pool.
FIG. 7 is a cross-sectional view showing a state in which block ice is completely formed by completely freezing.
FIG. 8 is a perspective view showing block-like ice taken out of the ice making frame.
FIG. 9 is a perspective view showing a plate-like ice cut from the upper side of the block-like ice.
FIG. 10 is a perspective view showing a plate-like ice cut out from the lower side of the block-like ice.
[Explanation of symbols]
1 Mixture 2 Ice making frame 3 Antifreeze 4 Ice making pool 5 Freezing section 6 Mixture pool 7 Pump 8 Water absorption hose 9 Drainage hose 10 Block ice

Claims (2)

A mixture of neutral water, acids such as hydrochloric acid and acetic acid, and sodium hypochlorite was added to an ice making frame, and this ice making frame was submerged in an ice making pool where antifreeze cooled below freezing circulated. In the ice making process, the mixed liquid pool in the central part that is not frozen is intermittently stirred in a manner similar to the stationary state, and the concentration of the mixed liquid is slowly and uniformly settled. A method for producing sterilized ice, characterized in that milky white ice is produced while the ice is formed, and the obtained block-shaped sterilized ice is crushed with a crusher. As a stirring method, insert the water absorption hose of the pump into the bottom of the unfrozen mixed liquid pool, insert the drain hose into the top of the mixed liquid pool, and use the pump to set the mixed liquid close to a stationary state. intermittently stirred, the manufacturing method of sterilizing ice according to claim 1, wherein Rukoto is convection while pulling up the water hose so as not confined to the freezing unit.

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