JP5871752B2 - Liquid egg heat treatment method and heat treatment apparatus - Google Patents

Description

  The present invention relates to a heat treatment technique for liquid eggs for heat sterilization of liquid eggs.

  In the restaurant business that provides customers with egg dishes and the food processing industry that manufactures foods made from eggs, liquid eggs that have been preliminarily heat-sterilized at the factory and packed in containers are used. Such sterilized liquid eggs used as food for cooking include liquid egg yolk only of egg yolk, liquid egg white only of egg white, and liquid whole egg in which egg white and egg yolk are mixed. In order to mass-produce sterilized liquid eggs for cooking, as described in Patent Document 1, a shelled egg is divided by a cracking machine, and a strainer, a broken piece of egg color, and the like are first separated from a liquid egg. To do. The separated liquid egg is heat-treated as it is or after being refrigerated and stored in a container.

  In order to heat sterilize liquid eggs, conventionally, in addition to a method of heating at 60 ° C. for 3.5 minutes by a heater such as a Joule heater, as described in Patent Document 1, a batch sterilization tank, a plate There has been proposed a method of heating a liquid egg at 58 ° C. for 10 minutes using a heat exchanger or a Joule heater. Moreover, as described in Patent Document 2, the heating process is divided into two stages, and the first heating process is heated at 57 to 60 ° C. for 1 to 60 seconds, and after cooling, the heating process is 55 to 58 ° C. in the second heating process. A method of heating for 3.5 to 10 minutes is proposed, and a plate-type indirect heating type heat exchanger is used for each heating step.

JP 10-248532 A Japanese Patent Laid-Open No. 2002-165583

  For example, when cooking an egg soup, if an unsterilized liquid egg that has been split and taken out of the shell is put into hot water, the egg soup that has become a hardened egg can be cooked. On the other hand, when a liquid egg sterilized by conventional techniques is put into hot water, the egg does not become solid, but the egg is dispersed in the hot water so that it becomes cloudy and becomes cloudy. It turns out. This white turbidity phenomenon is not limited to cooking egg soup, and in other egg dishes, the heat-sterilized liquid egg has a problem in cohesion even when heated. In this way, the phenomenon that the sterilized liquid egg becomes less cohesive than the non-sterilized liquid egg is particularly a plate-type or tube-type indirect heating type heat in order to mass-produce sterilized liquid eggs. It is known that the liquid egg heated to the sterilization temperature while continuously transporting the liquid egg to the flow path using the exchanger is more prominent than the case where the liquid egg is heated by the Joule heater.

  When a liquid egg is heated by an indirect heating type heat exchanger, the liquid egg will meander and flow through the heat exchanger, and the liquid egg will receive a large shearing force from the start to the end of heating. Since it is subject to thermal damage, it is considered that when a liquid egg sterilized by an indirect heating type heat exchanger is cooked, it becomes cloudy rather than when the liquid egg is heated by a Joule heater. However, even when a liquid egg is sterilized by a Joule heater, if the liquid egg after sterilization is cooked, it may become cloudy.

  According to various experiments, the liquid egg is preheated at a temperature lower than its protein denaturation temperature, and then heated to the sterilization temperature. When heated, it was found that the liquid egg after sterilization treatment is highly condensable and does not become cloudy regardless of whether the heating method is an indirect heating type heat exchanger or a Joule heating type heating device.

  An object of the present invention is to provide a heat treatment technique that makes the agglomeration property of a heat-treated liquid egg close to that of an unsterilized liquid egg.

The liquid egg heat treatment method of the present invention is a liquid egg heat treatment method for heat sterilizing a liquid egg, wherein the unsterilized liquid egg which has been split and taken out of the shell is converted into a protein transformant of the liquid egg. A preheating step of heating the preheat temperature to a temperature lower than the preheating temperature, a preheating temperature holding step of holding the liquid egg heated to the preheating temperature at the preheating temperature, and after being held at the preheating temperature The preheating includes: a sterilization heating step of heating the liquid egg to a sterilization temperature by causing the liquid egg to generate heat by Joule heat; and a sterilization temperature holding step of maintaining the liquid egg heated to the sterilization temperature at the sterilization temperature. The temperature is 40 ° C. or more and less than 53 ° C., the preheating temperature holding time is 1 minute or more, the sterilizing temperature and the sterilizing temperature holding time are the same, and the sterilizing temperature is 60 ° C. and the sterilizing temperature holding time is 3 The standard for sterilization treatment equivalent to 5 minutes Features.

The liquid egg heat treatment apparatus of the present invention is a liquid egg heat treatment apparatus for heat sterilization of a liquid egg, wherein an unsterilized liquid egg which has been split and taken out of a shell is converted into a protein transformant of the liquid egg. A preheating unit that heats the liquid egg heated to the preheating temperature to the preheating temperature, a preheating temperature holding unit that holds the liquid egg heated to the preheating temperature, and a temperature after being held at the preheating temperature. A sterilization heating unit that heats the liquid egg by Joule heat to heat the liquid egg to the sterilization temperature, and a sterilization temperature holding unit that maintains the liquid egg heated to the sterilization temperature at the sterilization temperature, and the preheating The temperature is 40 ° C. or more and less than 53 ° C., 1 minute or more of the preheating temperature holding time, the sterilizing temperature and the sterilizing temperature holding time are 60 ° C. and the sterilizing temperature holding time is 3 .Sterile treatment equivalent to 5 minutes It is characterized by being a standard.

  According to the present invention, the liquid egg is heated to a preheating temperature lower than its protein denaturation temperature, and then the preheating temperature is maintained. Therefore, in the preheating temperature maintaining step, the liquid egg that has become the preheating temperature is in a filamentous form. It is played back in a connected or solid state. The liquid egg in the regenerated state is heated to the sterilization temperature in a short time by Joule heating, and then kept at the sterilization temperature for a certain period of time, thereby completing the heat treatment of the liquid egg. When the liquid egg sterilized by heating is cooked in this manner, a sterilized liquid egg having a cohesive property close to that of an unsterilized liquid egg is obtained.

It is a flowchart which shows the heat processing method of the liquid egg which is one Embodiment. It is the schematic which shows the heat processing apparatus of the liquid egg which is one embodiment. It is the schematic which shows the heat processing apparatus of the liquid egg which is other embodiment. (A) is a characteristic diagram which shows the temperature change of the liquid egg when it heat-processes with the heat processing apparatus of the liquid egg shown in FIG. 2, (B) is by the heat processing apparatus of the liquid egg shown in FIG. It is a characteristic diagram which shows the temperature change of the liquid egg when heat-processing. It is an expanded sectional view which shows an example of the sterilization heating unit shown by FIG. 2 and FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The illustrated heat treatment apparatus is applied to heat sterilize a liquid egg for cooking using an unsterilized whole egg as a processing object. As shown in FIG. 1, the heat treatment process of the liquid egg has an egg breaking process 11 to a packaging process 17. In the egg breaking process 11, the egg is broken by an egg breaking machine (not shown) and the egg yolk is broken. And egg white are taken out. The extracted egg yolk and egg white are stirred by a stirrer (not shown). The stirred liquid egg is transferred to the preheating step 12 as it is, or refrigerated for about one day and then transferred to the preheating step 12. In this preheating step 12, the unsterilized liquid egg at the initial temperature T 0 that has been split and taken out of the shell is heated to a preheating temperature T 1 that is lower than the protein transformation temperature of the liquid egg, and constant in the preheating temperature holding step 13. Hold at preheat temperature for hours.

  The protein denaturation temperature of the liquid egg is 53 ° C. or higher. When the liquid egg is continuously heated to 53 ° C. or higher, the stirred liquid egg does not become connected, but the temperature lower than the protein denaturation temperature is set to a preheating temperature T1, for example, about 40 to 53 ° C. After preheating the egg, if the liquid egg is held at the preheating temperature T1 in the preheating temperature holding step 13 for the preheating temperature holding time H1 or more, the liquid egg separated at the time of preheating is regenerated to a connected state. found. In order to regenerate the separated liquid egg, it has been found that it is necessary to keep the preheating temperature for 1 minute or more in the preheating temperature holding step 13. It was possible to regenerate the liquid egg.

The liquid egg that has finished the preheating temperature holding step 13 is conveyed to the sterilization heating step 14 and heated to the sterilization temperature T2. In the sterilization heating step 14, the liquid egg is heated by sterilization by Joule heat to the sterilization temperature T2 in a short time of about 100 seconds. The liquid egg heated to the sterilization temperature T2 is maintained at the sterilization temperature T2 in the sterilization temperature holding step 15 for a sterilization holding time H2 or longer, and is sterilized and heated. The sterilization treatment condition is that when the sterilization temperature T2 is 60 ° C., the sterilization temperature holding time H2 is 3.5 minutes . The sterilization temperature holding time H2 as a sterilization treatment standard is 2.30 minutes or more when the sterilization temperature T2 is 61 ° C., and 1.52 minutes or more when the sterilization temperature T2 is 62 ° C. When the temperature T2 is 63 ° C., it is 1.00 minutes or longer. Thus, when the sterilization temperature T2 is increased, even if the sterilization temperature holding time H2 is shortened, the sterilization treatment standard corresponding to 60 ° C. and 3.5 minutes is satisfied. When the temperature of the sterilization temperature T2 is higher than the above temperature, the minimum value of the sterilization temperature holding time H2 that satisfies the sterilization treatment standard is as follows, and the parenthesis indicates the sterilization temperature holding time corresponding to the sterilization temperature. Show.

T2 = 64 ° C. (H2 = 0.66 min), T2 = 65 ° C. (H2 = 0.43 min), T2 = 66 ° C. (H2 = 0.28 min), T2 = 67 ° C. (H2 = 0.19 min) ), T2 = 68 ° C. (H2 = 0.12 min), T2 = 69 ° C. (H2 = 0.081 min), T2 = 70 ° C. (H2 = 0.053 min), T2 = 71 ° C. (H2 = 0.0 min). 035 min), T2 = 72 ℃ (H2 = 0.023 min), T2 = 73 ℃ (H2 = 0.015 min), T2 = 74 ℃ (H2 = 0.010 min), T2 = 7 5 ℃ ( H2 = 0.007 minutes)
Thus, when the sterilization temperature T2 is increased, if the sterilization temperature T2 is maintained for the sterilization temperature holding time H2 in parentheses, the sterilization treatment standard corresponding to 60 ° C. and 3.5 minutes is satisfied.

  The sterilized liquid egg is cooled to room temperature or refrigerated storage temperature T0 in the cooling step 16 and packaged in a container or package in the packaging step 17. However, the cooling method for the heat-treated liquid egg may be a natural cooling method.

  FIG. 2 is a schematic view showing a liquid egg heat treatment apparatus 20 that embodies the heat treatment method shown in FIG. This liquid egg heat treatment apparatus 20 has a hopper 21 into which a liquid egg that has been split and stirred is charged. This hopper 21 is connected to a preheating unit 23 by a pipe 22a. Eggs are continuously conveyed to the preheating unit 23. The preheating unit 23 has a heating channel provided with a pair of electrodes, and heats the liquid egg at a stretch to the preheating temperature T1 by generating heat by Joule heat while conveying the liquid egg to the heating channel. . The pipe 22a is provided with an opening / closing valve 24 for opening and closing the state in which the flow path in the pipe 22a is opened and the state in which the flow path is closed, and the liquid egg in the hopper 21 is supplied to the preheating unit 23. A pump 25 is provided.

  The liquid egg preheated by the preheating unit 23 is transported to the preheating temperature holding unit 26 through the pipe 22b with the temperature lower than the protein denaturation temperature as the preheating temperature T1. In the preheating temperature holding unit 26, the liquid egg heated to the preheating temperature T1 is held at the preheating temperature holding time H1 and the preheating temperature T1 described above. When the liquid egg is held at a preheating temperature T1 lower than the protein denaturation temperature, the preheated liquid egg is regenerated to be in a stringed state, and the regenerated liquid egg is sterilized and heated by the pipe 22c. It is conveyed to the unit 27. This sterilization heating unit 27 is formed by a Joule heating unit that heats the liquid egg, which has been held at the preheating temperature T1, to Joule heat and heats it to the sterilization temperature T2. Since the liquid egg can be heated to the desired sterilization temperature T2 above the protein denaturation temperature by Joule heating in a short time, heat damage applied to the liquid egg can be reduced.

  The liquid egg heated to the sterilization temperature T2 is conveyed to the sterilization temperature holding unit 28 through the pipe 22d, and is held by the sterilization temperature holding unit 28 for the sterilization temperature holding time H2. Thereby, the heat sterilization process of a liquid egg is complete | finished. The liquid egg that has been subjected to the heat sterilization process is transported to the cooling unit 29 through the pipe 22e, and is cooled to the refrigeration temperature or the normal temperature by the cooling unit 29. The cooling unit 29 has a cooling jacket 31 to which the cooling liquid is supplied outside the cooling flow path 30 for guiding the liquid egg, and the cooling liquid from the cooler 32 is circulated and supplied to the cooling jacket 31. The liquid egg cooled by the cooling unit 29 is conveyed to the collection container 33 through the pipe 22f. When a predetermined amount of liquid egg is supplied to the recovery container 33, the liquid egg in the recovery container 33 is transported to the packaging step 17 and stored in the container or package.

  FIG. 5 is an enlarged cross-sectional view of the sterilization heating unit 27 shown in FIG. The sterilization heating unit 27 includes a heating pipe having a circular cross section, that is, a tubular member 42, in which a heating channel 41 for guiding the liquid egg is formed. The tubular member 42 is composed of seven ring-shaped electrodes 43 and six cylindrical bodies 44 disposed therebetween. As described above, the Joule heating type sterilization heating unit 27 includes the tubular member 42 constituted by the plurality of electrodes 43 and the plurality of cylindrical bodies 44, and the adjacent electrodes 43 form a pair with the tubular member 42. Is provided. Each electrode 43 is formed of a conductor such as titanium, and each cylindrical body 44 is formed of an insulator such as resin. At both ends of the tubular member 42, inflow and outflow side joint portions 45 and 46 made of an insulator are attached. A pipe 22 c is connected to the inflow side joint part 45, and a pipe 22 d is connected to the outflow side joint part 46. A power supply unit 47 is connected to each electrode 43 via a cable, and a high frequency current is supplied from the power supply unit 47 so that the pair of electrodes 43 adjacent to each other in the flowing direction of the liquid egg have opposite polarities. Is done. In addition, the number of the electrodes 43 provided in the sterilization heating unit 27 is arbitrarily set according to the heating temperature or the like.

  The preheating unit 23 shown in FIG. 2 is a Joule heating type similarly to the sterilization heating unit 27, and has a plurality of ring-shaped electrodes and a plurality of cylindrical bodies disposed therebetween. . The preheating temperature holding unit 26 and the sterilization temperature holding unit 28 shown in FIG. 2 are each provided with a heating channel, and the preheating temperature holding unit 26 is provided with a channel for guiding the liquid egg inside, Is provided with a heat insulating material to keep the liquid egg at a preheating temperature. Similarly, the sterilization temperature holding unit 28 is provided with a flow path for guiding the liquid egg inside and a heat insulating material is provided outside to hold the liquid egg at the sterilization temperature. However, in order to prevent a decrease in the preheating temperature and the sterilization heating temperature, a jacket in which a heat retaining medium is circulated and supplied to the preheating temperature holding unit 26 and the sterilization temperature holding unit 28 may be provided outside.

  FIG. 3 is a schematic view showing a liquid egg heat treatment apparatus according to another embodiment. In FIG. 3, members that are the same as those in the heat treatment apparatus illustrated in FIG. 2 are assigned the same reference numerals. As shown in FIG. 3, the preheating unit 23 a is provided with a heating jacket 36 outside the heating flow path 35 to which the liquid eggs in the hopper 21 are supplied. A heated heating medium is circulated and supplied. Thus, the preheating unit 23a shown in FIG. 2 is a Joule heating type, whereas the preheating unit 23a is an indirect heating type.

  4A is a characteristic diagram showing the temperature change of the liquid egg when the heat treatment is performed by the liquid egg heat treatment apparatus shown in FIG. 2, and FIG. 4B is a characteristic diagram of the liquid egg shown in FIG. It is a characteristic diagram which shows the temperature change of the liquid egg when heat-processing with a heat processing apparatus.

  As shown in FIG. 4 (A), a liquid egg that has been refrigerated at about 5 to 10 ° C. is heated to a preheating temperature T 1 lower than its protein denaturation temperature by a Joule heating type preheating unit 23, for example, 50 ° C. The preheating temperature holding unit 26 held the preheating temperature T1 for a preheating temperature holding time H1 of 1 minute or longer. Thereafter, the mixture was heated to a sterilization temperature T 2 of 60 ° C. by a Joule heating type sterilization heating unit 27. The time required for heating was about 100 seconds, and the liquid egg heated to 60 ° C. as the sterilization temperature T 2 was held at the sterilization temperature T 2 by the sterilization temperature holding unit 28 for 3.5 minutes. The sterilized liquid egg was cooled to the storage temperature. When the liquid egg thus heat-treated was poured into hot water, the liquid egg had almost the same cohesion as the unsterilized liquid egg, and the liquid egg did not become cloudy.

  As shown in FIG. 4B, when the preheating unit 23a is preheated to the preheating temperature T1, which is lower than the protein denaturation temperature, the temperature is raised to the preheating temperature T1 rather than the Joule type preheating unit 23. The time for making it longer. However, even if heating is performed up to the preheating temperature T1 by the indirect heating type preheating unit 23a, the preheating temperature is maintained as in FIG. 4A, the sterilization temperature T2 is heated, and the sterilization temperature T2 is maintained. The liquid egg subjected to the heat treatment had almost the same cohesiveness as the unsterilized liquid egg, and the liquid egg did not become cloudy.

  On the other hand, the liquid egg after being kept at the preheating temperature T1 was heated to the sterilization temperature T2 by an indirect heating type heater without being kept at the preheating temperature T1. In this way, when the heat treatment was continuously performed up to the heating temperature equal to or higher than the protein denaturation temperature without passing through the preheating temperature holding step, the liquid egg aggregated when the liquid egg after the heat treatment was poured into hot water. It became cloudy without having sex.

  Thus, after passing through the preheating process which heats to preheating temperature T1 below protein denaturation temperature, and the preheating temperature holding process hold | maintained to the temperature for more than a fixed time, by the Joule heating type sterilization heating unit 27, it is a short time. When heated to a sterilization temperature equal to or higher than the protein denaturation temperature, it was found that the liquid egg after the heat treatment has almost the same cohesiveness as the unsterilized liquid egg.

  The preheating temperature T1 is set to 50 ° C., which is less than 53 ° C., which is the protein denaturation temperature of the liquid egg, and the preheating temperature holding time H1 is changed to hold a large number of liquid eggs at the preheating temperature. The cohesiveness of liquid eggs that had been subjected to heat sterilization treatment according to the sterilization treatment standard at 60 ° C. and sterilization temperature holding time H 2 of 3.5 minutes was confirmed. The cohesiveness was confirmed by injecting the heat-sterilized liquid egg into hot water to produce kakidama.

  The liquid egg that had been preheated at a preheating temperature holding time H1 of 30 seconds and was heat-sterilized according to the sterilization standard was turbid in hot water, and a thin membrane-like connection was obtained in the liquid egg, but the connection was slightly weak . For this reason, it turned out that cohesion is bad compared with the case where a ball is manufactured using unsterilized liquid eggs.

  On the other hand, for each of the case where the preheating temperature holding time H1 is 1 minute and the case where the preheating temperature holding time H1 is 1.5 minutes, the liquid egg subjected to the heat sterilization treatment based on the sterilization treatment standard has a viscosity and a thick film. The hot water was not cloudy. The liquid eggs that had been subjected to the heat sterilization treatment according to the sterilization treatment standard for each of the preheating temperature holding time H1 of 2 minutes and 2.5 minutes had a slight turbidity in the hot water, but the viscosity was low. Yes, it was solidified without being connected to a film, and a cohesiveness close to that of an unsterilized liquid egg was obtained. Liquid eggs that have been subjected to heat sterilization treatment on the basis of the sterilization treatment standard when the preheating temperature holding time H1 is set to 3 minutes, 3.5 minutes, and 4 minutes have higher viscosity. The film solidified without being connected to a film, and a cohesiveness close to that of an unsterilized liquid egg was obtained. When the preheating temperature holding time H1 was 4.5 minutes and 5 minutes, the liquid eggs subjected to the heat sterilization treatment on the basis of the sterilization treatment standard became large aggregates. Although turbidity occurred in the hot water, there was no cloudiness of the liquid egg, and an agglomerated kakidama similar to an unsterilized liquid egg was obtained.

  Furthermore, the liquid egg which performed the heat sterilization process on the basis of the sterilization processing standard about each when the preheating temperature holding time H1 is 6 minutes, 7 minutes, 8 minutes and 10 minutes. The agglomerates became small and scattered, and the turbidity of hot water was stronger than that described above, but there was no liquid egg white turbidity, and a coherent kakidama similar to unsterilized liquid eggs was obtained.

  Thus, when the preheating temperature T1 is set to 50 ° C. and the preheating temperature holding time H1 is changed and a large number of liquid eggs are held at the preheating temperature, the preheating temperature can be increased by setting the preheating temperature holding time H1 to 1 minute or more. It was found that a sterilized liquid egg having a condensability close to that of an unsterilized liquid egg can be obtained as compared with a sterilized liquid egg that has been heat sterilized without holding. However, if the preheating temperature holding time H1 is lengthened, the time for continuously heat-treating the sterilized liquid egg becomes longer. Therefore, considering the processing efficiency, it is preferable to shorten the preheating temperature holding time H1.

  The preheating temperature T1 may be 50 ° C. or less as long as it is lower than the protein denaturation temperature of the liquid egg, and the same result can be obtained when the preheating temperature T1 is 40 ° C. Considering the heating time to the temperature, the preheating temperature T1 is preferably a temperature lower than 53 ° C. which is the protein denaturation temperature of the liquid egg and close to it.

  In the preheating units 23 and 23 of the heat treatment apparatus shown in FIGS. 2 and 3, the liquid egg is preheated while being transported into the pipeline, and the preheating temperature holding unit 26 also transports the liquid egg into the conduit. However, the preheating temperature is maintained for a predetermined time, but a batch type preheating unit may be used by using a container as each preheating unit. Similarly, a preheating temperature holding unit or a batch type preheating temperature holding unit may be used. In each case, the sterilization heating unit 27 and the sterilization temperature holding unit 28 are continuous.

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. For example, as the Joule heating type preheating unit 23 and the sterilization heating unit 27, two plate-like electrodes are arranged to face each other on the inner surface of a heating pipe having a square cross section in which a heating channel is formed. It is good also as a form, and it is good also as a form which attached the plate-shaped electrode to the both end surfaces of a heating pipe so as to oppose each other.

DESCRIPTION OF SYMBOLS 11 Egg breaking process 12 Preheating process 13 Preheating temperature holding process 14 Sterilization heating process 15 Sterilization temperature holding process 16 Cooling process 17 Packaging process 20 Heat processing apparatus 21 Hopper 22a-22f Pipe 23,23a Preheating unit 24 On-off valve 25 Pump 26 Preheating temperature Holding unit 27 Sterilization heating unit 28 Sterilization temperature holding unit 29 Cooling unit 31 Cooling jacket 32 Cooling machine 33 Recovery container 35 Heating channel 36 Heating jacket 37 Heating device 41 Heating channel 42 Tubular member 43 Electrode 44 Cylindrical body 45, 46 Joint part 47 Power supply unit

Claims (3)

A liquid egg heat treatment method for heat sterilizing a liquid egg,
A preheating step of heating an unsterilized liquid egg that has been split and removed from the shell to the preheating temperature with a temperature lower than the protein transformation temperature of the liquid egg as the preheating temperature;
A preheating temperature holding step of holding the liquid egg heated to the preheating temperature at the preheating temperature;
A sterilization heating step of heating the liquid egg to a sterilization temperature by heating the liquid egg after being held at the preheating temperature by Joule heat;
A sterilization temperature maintaining step of maintaining the liquid egg heated to the sterilization temperature at the sterilization temperature;
Have
The preheating temperature is 40 ° C. or more and less than 53 ° C., the preheating temperature holding time is 1 minute or more, the sterilizing temperature and the sterilizing temperature holding time are set to be 60 ° C. and the sterilizing temperature holding time. Is a sterilization treatment standard corresponding to 3.5 minutes. A liquid egg heat treatment apparatus for heat sterilizing a liquid egg,
A preheating unit that heats the unsterilized liquid egg that has been split and removed from the shell to the preheating temperature at a temperature lower than the protein denaturation temperature of the liquid egg,
A preheating temperature holding unit for holding the liquid egg heated to the preheating temperature at the preheating temperature;
A sterilization heating unit that heats the liquid egg to a sterilization temperature by causing the liquid egg after being held at the preheating temperature to generate heat by Joule heat;
A sterilization temperature holding unit for holding the liquid egg heated to the sterilization temperature at the sterilization temperature;
Have
The preheating temperature is 40 ° C. or more and less than 53 ° C., the preheating temperature holding time is 1 minute or more, the sterilizing temperature and the sterilizing temperature holding time are set to be 60 ° C. and the sterilizing temperature holding time. Is a sterilization treatment standard corresponding to 3.5 minutes.   3. The liquid egg heat treatment apparatus according to claim 2, wherein the preheating unit is a Joule heating unit that heats the liquid egg to the preheating temperature by generating heat by Joule heat while flowing the liquid egg into the heating channel. A heat treatment apparatus for liquid eggs.

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