阅读说明：本技术 连续低温食物巴氏灭菌系统和方法 (Continuous low temperature food pasteurization system and method ) 是由 J·R·斯特朗 R·D·斯托卡德 J·A·霍克 于 2014-07-02 设计创作，主要内容包括：一种连续低温食物巴氏灭菌系统(10),其包括用于将食品(FP)输送通过巴氏灭菌室(40)的输送机系统(20)。预加热器(140)可以位于所述巴氏灭菌室的上游,并且任选地后加热器(160)可以位于所述巴氏灭菌室的下游。在巴氏灭菌后,在所述输送机系统将食品输送通过冷冻器时,冷却器和/或冷冻器(100)快速地冷却和/或冷冻食品。控制系统(250)控制所述巴氏灭菌系统的运行以确保杀灭存在于食品的表面上和/或内部中的期望百分比的病原微生物。(A continuous low temperature food pasteurization system (10) includes a conveyor system (20) for conveying Food Products (FP) through a pasteurization chamber (40). A pre-heater (140) may be located upstream of the pasteurization chamber, and optionally a post-heater (160) may be located downstream of the pasteurization chamber. After pasteurization, the cooler and/or freezer (100) rapidly cools and/or freezes the food product as the conveyor system conveys the food product through the freezer. A control system (250) controls operation of the pasteurization system to ensure that a desired percentage of pathogenic microorganisms present on the surface and/or in the interior of the food product are killed.)

1. A continuous low temperature pasteurization and cooking assembly system for continuously pasteurizing and cooking a food product, wherein the food product is meat, fish, poultry, pasta, bread dough, pizza dough, or eggs, at a low maximum temperature for a sufficient duration to kill pathogenic microorganisms on and in the food product and to cook the food product to a desired level, characterized in that:

(a) a conveying system for continuously conveying the food products to be pasteurized and cooked;

(b) a low temperature pasteurization chamber through which the conveyor system passes, wherein the conveyor system travels along a helical path within the low temperature pasteurization chamber;

(c) a pasteurization medium generator in fluid flow communication with the pasteurization chamber, the pasteurization medium generator providing heated air for heating the interior of the low temperature pasteurization chamber to a temperature range of 55 ℃ to 70 ℃ and supplying moisture to the interior of the low temperature pasteurization chamber at a humidity of 80 to 100%;

(d) a measurement system for measuring operating parameters of the system for continuous pasteurization and cooking of food products, the operating parameters including the speed of the conveyor system and the temperature and humidity in the low temperature pasteurization chamber throughout the conveyance of food products through the pasteurization chamber with the conveyor system;

(e) a control system for monitoring operating parameters of the pasteurization system for continuous pasteurization and cooking of food products, the operating parameters including:

(i) a speed of a conveyor in the pasteurization chamber to determine whether the conveyor is operating at a speed within a conveyor speed set point range that provides sufficient residence time for the food product in the low temperature pasteurization chamber to kill a desired percentage of pathogenic microorganisms present on and in the food product;

(ii) a temperature of at least one of:

heated air supplied to the low temperature pasteurization chamber to determine whether the interior of the low temperature pasteurization chamber is maintained at a temperature set point in the range of 55 ℃ to 70 ℃;

a food product to determine if the interior of the food product reaches a set point of 52 ℃ to 70 ℃ within a sufficiently long time required to reach a desired level of lethality of pathogenic microorganisms on and in the food product;

(iii) moisture supplied to the pasteurization chamber to determine whether the moisture content of the pasteurization medium in the low temperature pasteurization chamber is maintained at a moisture setpoint in the range of 80 to 100% humidity; and

(f) said control system being operable to simulate the lethality of said pathogenic microorganisms during pasteurization and cooking of the food product, wherein said simulation comprises determining whether the interior of the food product has reached a set point of 52 ℃ to 70 ℃ for a sufficient period of time required to reach a desired level of lethality of pathogenic microorganisms on and in the food product by taking into account at least the temperature of the heated air supplied to the low temperature pasteurization chamber and the moisture content of said pasteurization medium;

and based on such simulation, if desired, occurring during pasteurization and cooking, initiating a remedial procedure to kill a desired level of pathogenic microorganisms on and in the food product to effect pasteurization of the food product if the measured temperature in the low temperature pasteurization chamber, the measured temperature of the food product, and/or the humidity in the low temperature pasteurization chamber deviate sufficiently from a preselected set point temperature and/or humidity range, or if the speed of the conveyor deviates sufficiently from a preselected set point speed so that a desired percentage of pathogenic microorganisms on and in the food product are not killed; and

(g) wherein the corrective procedure initiated by the control system is characterized by: issuing a notification of a deviation in one or more operating parameters, automatically changing one or more operating parameters, or providing a recommendation to change one or more operating parameters, wherein the one or more operating parameters are selected from the group consisting of:

(i) the temperature of the pasteurization chamber;

(ii) a moisture level in the pasteurization chamber;

(iii) the speed of the conveying system;

(iv) the temperature of the food entering the pasteurization zone;

(v) a residence time of the transport system in the pasteurization chamber;

(vi) a loading level of food product on the conveyor system; and

(vii) diversion of food products from the conveyor system.

2. The continuous low temperature pasteurization and cooking assembly system of claim 1 wherein the conveyor system is characterized by a conveyor belt disposed in stacked tiers in the pasteurization chamber, the food products exiting the pasteurization chamber on the conveyor belt atop the stacked tiers.

3. The continuous low temperature pasteurization and cooking assembly system of claim 1, further characterized by a circulation system for circulating the pasteurization medium through the low temperature pasteurization chamber; a control system operable to control the circulation system such that the flow of circulating medium in the pasteurization chamber is primarily in a generally horizontal and/or downward direction above the food product.

4. The continuous low temperature pasteurization and cooking assembly system of claim 1 further characterized by a pre-heater disposed upstream relative to the low temperature pasteurization chamber and relative to the conveyor system to pre-heat the food being conveyed by the conveyor system prior to the food entering the low temperature pasteurization chamber, and operable to optionally provide a desired food color and flavor through a strong pre-heating process that raises the surface temperature of the food.

5. The continuous low temperature pasteurization and cooking assembly system in accordance with claim 4, wherein said pre-heater is operable to pre-heat the food product to approximately the final desired pasteurization temperature in said low temperature pasteurization chamber such that the heat treatment of the food product in said low temperature pasteurization chamber maintains the food product at such temperature for the time required to kill the desired level of pathogenic microorganisms on and in the food product.

6. The continuous low temperature pasteurization and cooking assembly system of claim 1 further characterized by a liquid circulation system for directing juice refined from food products onto food products being conveyed on the conveyor system in the low temperature pasteurization chamber and/or the pre-heating chamber during operation of the pasteurization system, and optionally heating the liquid prior to directing the liquid onto the food products.

7. The continuous low temperature pasteurization and cooking assembly system of claim 1, wherein the measurement system measures the temperature of the food sample while in the low temperature pasteurization chamber.

8. The continuous low temperature pasteurization and cooking assembly system of claim 1, further characterized by:

a first cooler disposed downstream of the pasteurization chamber to rapidly cool the food product exiting the pasteurization chamber to an intermediate temperature;

a high intensity heat source for rapidly heating the outer surface of the cooled food product; and

a second cooler and/or freezer for rapidly cooling and/or freezing the food product.

9. The continuous low temperature pasteurization and cooking assembly system of claim 1, further characterized by: the control system is operable to simulate the lethality of the pathogenic microorganisms and, based on such simulation, initiate a remedial procedure including one or more of changing the operating parameters, if necessary, to kill a desired level of pathogenic microorganisms on and in the food product while maintaining a desired food product quality by maintaining the core of the food product below the low maximum temperature.

10. The continuous low temperature pasteurization and cooking assembly system of claim 1 wherein the control system optionally measures a parameter of the temperature of the food product as it enters the pasteurization zone and a parameter of the temperature of the food product immediately following the pasteurization zone.

11. The continuous low temperature pasteurization and cooking assembly system of claim 1, wherein:

the pasteurization medium is further characterized by moisture supplied to the interior of the low temperature pasteurization chamber;

the measurement system measuring a moisture level in the low temperature pasteurization chamber; and

the control system monitors operating parameters of the moisture level in the low temperature pasteurization chamber to determine whether such moisture level is maintained at a set point in the 80 to 100% humidity range.

12. A method for continuous pasteurization and cooking of a food product for a sufficient duration to kill a desired percentage of pathogens located on and in the food product and to cook the food product to a desired level at a predetermined maximum temperature, wherein the food product is meat, fish, poultry, pasta, bread dough, pizza dough or egg, and wherein the predetermined maximum temperature is from 55 ℃ to 70 ℃, the method being characterized by employing the continuous low temperature pasteurization and cooking assembly system of any one of claims 1 to 11 and comprising the steps of:

(a) providing a pasteurization zone under first operating parameters including a moisture level of 80% to 100% of temperature and humidity of said pasteurization zone having a temperature setpoint of between 55 ℃ and 70 ℃ throughout the pasteurization process;

(b) conveying the food loaded onto the conveyor along a helical path through a pasteurization zone under second operating parameters including the speed of the conveyor which retains the food in the pasteurization zone to reach a setpoint temperature of the food for a time sufficient to kill a desired percentage of pathogens present on and in the food and cook the food to a desired level;

(c) measuring the temperature level in the pasteurization zone and/or the temperature of the food; and

(d) if the measured temperature in the pasteurization zone and/or the temperature of the food product deviates sufficiently from the setpoint temperature range so as not to kill a desired percentage of pathogens on and in the food product, a remedial procedure is initiated so as to kill a desired level of pathogens on and in the food product.

13. The method of claim 12, wherein the setpoint temperature in the pasteurization zone is selected from the group consisting of a dry bulb temperature, a wet bulb temperature, and a dew point temperature in the range of 55 ℃ to 70 ℃.

14. The method of any of claims 12 or 13, further characterized by cooling or freezing the food product after it is conveyed through the pasteurization zone.

15. The method of claim 12, further characterized by prior to cooling or freezing the food product:

cooling the food product to a surface temperature below 40 ℃; and

intense heat is applied to the surface of the food product to achieve the desired color and/or flavor.

16. The method of claim 12, further characterized by preheating the food product prior to entering the pasteurization zone using one or more of the following sources of thermal energy: steam, radio frequency radiation, infrared radiation, convection, mixed liquid and gas convection, condensation, conduction, and microwave radiation.

17. The method of claim 12 further characterized by applying intense surface heat to the food product to achieve a desired color and/or flavor before the food product enters the pasteurization zone or after the food product exits the pasteurization zone and before the food product is cooled or frozen.

18. The method of claim 12 further characterized by collecting liquid refined from the food product during said pasteurization of the food product and heating said liquid to a temperature of at least 48 ℃ if necessary to assist in heating the food product to the desired temperature setting prior to applying said collected refined liquid to the food product.

Background

Typically, food products for commercial distribution, such as meat, poultry, and fish, are first cooked to an internal temperature (greater than 73.9 ℃ [165 ° f ]) sufficient to destroy any pathogens, such as e.g. e. When the food reached 73.9 ℃ [165 ℃ F. ], the bacteria were immediately killed. However, a large amount of heat must be conducted through the surface to the interior of the food product to reach an internal temperature of 73.9 ℃ [165 ° f ], which cooks the food product completely and causes it to become relatively dry and hard after commercial storage and distribution, when reheated for consumption. This is the case due to the expulsion of juice from the food, denaturation of protein in the food and refining of fat by the heat applied thereto.

Among the widely disparate methods of cooking food products, methods have been developed for cooking food at relatively low temperatures for a significant period of time in vacuum-sealed plastic bags. This method is called sous vide (sous) method. The sous vide cooking method differs from conventional cooking methods in three basic ways: (1) vacuum sealing raw food in a heat-sealable, food-grade plastic bag; and (2) food is cooked using precisely controlled heating to limit and control product variations, and (3) bacterial kill is not immediate, but occurs over time at lower temperatures. Vacuum packaging prevents evaporative loss of flavor volatiles and moisture during cooking and suppresses off-flavors caused by oxidation. Cooking at relatively low temperatures for extended periods of time can provide very tender products that are safe but still not "well done". This results in a particularly palatable and nutritious food. The vacuum seal also effectively transfers and controls heat from the water (or steam) to the food.

However, sous vide cooking can take a relatively long span of time and requires relatively expensive vacuum packaging. For example, cooking a beef patty by sous-vide cooking may take at least several hours, but does not provide a pleasing appearance for consumption at that temperature. Therefore, before the patty is provided, the exterior of the patty must be grilled using a very hot heat source to provide a pleasing appearance and flavor upon consumption. Thus, the cooking method by which sous-vide cooking is rendered unsuitable for commercial use by itself.

Pre-cooking of food products on an industrial scale is well known and includes pre-cooked meats such as beef, pork, and chicken. In a large scale precooking process, meat may be coated with a liquid marinade, then perhaps dry-blended, and then the coated meat is cooked at a temperature of at least 93 ℃ [200 ° f ], perhaps as high as above 148.9 ℃ [300 ° f ], until the internal temperature of the meat shows that it is high enough to instantaneously destroy pathogens therein. Such precooking of food products, including meat, suffers from the same drawbacks as normal cooking of meat, the expulsion of juice from the meat and the rendering of fat, leaving the meat in a dry, firm state. Accordingly, there is a need for a commercial system and method for sufficiently precooking/pasteurizing meat to eliminate pathogens, yet still provide the benefits of a sous vide type process. The present invention seeks to address this problem.

SUMMARY

This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

There is provided a system for continuous pasteurization of food products at low maximum temperatures for a sufficient duration to kill pathogens on and/or in the food products, comprising: a conveying system for continuously conveying the food products to be pasteurized; a low temperature pasteurization chamber through which the delivery system passes; a pasteurization medium generator in fluid flow communication with the pasteurization chamber, the pasteurization medium generator providing heated air for heating the interior of the pasteurization chamber and/or supplying moisture to the interior of the pasteurization chamber. The pasteurization system further includes a measurement system for measuring operational parameters of the pasteurization system, including the speed of the conveyor and the temperature and humidity in the low temperature pasteurization chamber. Further, a control system for monitoring the operating parameters of the pasteurization system is provided to determine whether the conveyor is operating at a speed within a set point range that provides sufficient residence time of food products in the pasteurization chamber to kill a desired percentage of pathogens present on and/or in the food products, the control system also monitoring the temperature of the heated air provided to the pasteurization chamber to verify the set point range of about 55 ℃ [131 ° f ] to about 70 ℃ [158 ° f ]; or monitoring the temperature of the food product to determine if the interior of the food product reaches a setpoint temperature of 52 ℃ [125.6 ° f ] to 70 ℃ [158 ° f ] for a sufficient amount of time to achieve a desired level of mortality from pathogens on and/or in the food product. A third set-point parameter monitored by the control system is whether the moisture in the pasteurization chamber is in the range of about 80 to 100% humidity. The control system is operable such that if the measured temperature and/or humidity deviates sufficiently from a preset set point temperature and/or humidity range, or if the speed of the conveyor deviates sufficiently from a preselected set point speed such that a desired percentage of pathogenic microorganisms are not killed, the control system initiates a remedial procedure comprising altering one or more of the operating parameters such that a desired level of pathogenic microorganisms are killed.

In yet another aspect of the present invention, the remedial procedure initiated by the control system includes issuing a notification of a deviation in the operating parameter. The initiation of the remedial procedure may also provide recommendations to the system operator regarding the settings that require a change in one or more of the operating parameters to achieve a desired level of kill of pathogenic microorganisms on and/or in the food product.

According to the invention, the corrective procedure executed by the control system may include automatically changing one or more of the operating parameters including the temperature in the pasteurization chamber, the moisture level in the pasteurization chamber, the speed of the conveyor system, the food loading level on the conveyor system, and diverting food from the conveyor system.

According to another aspect of the invention, the conveyor system comprises a conveyor belt arranged in stacked, almost horizontal layers in a pasteurization chamber. The food products enter the pasteurization chamber on a conveyor at the bottom of the stack and exit the pasteurization chamber on a conveyor at the top of the stack.

According to another aspect of the invention, the low temperature pasteurization system further comprises a circulation system for circulating the pasteurization medium through the low temperature pasteurization chamber. The control system is operable to control the circulation system such that the flow of the circulating medium within the pasteurization chamber is primarily in a generally horizontal and/or downward direction above the food product.

According to a further aspect of the invention, a pre-heater is located upstream with respect to the low temperature pasteurization chamber. The pre-heater is operable to pre-heat the food product prior to entering the pasteurization chamber.

According to a further aspect of the invention, a collection system collects refined juice from the food product in the low temperature pasteurization chamber. The circulation system may direct the refined juice onto the food product being conveyed on the conveying system, or the refined juice may be conveyed from the pasteurization chamber for storage or other use.

According to a further aspect of the invention, the continuous low temperature pasteurization system further comprises a cooler (cooler) or freezer (freezer) located downstream of the pasteurization chamber to rapidly cool and/or freeze the pasteurized food exiting the low temperature pasteurization chamber.

According to a further aspect of the invention, a post-pasteurization heating system is used to apply high intensity heat to the surface of the food product after it exits the low temperature pasteurization chamber and prior to entering the cooler and/or freezer.

The present invention also provides a method for continuously pasteurizing food products at a low maximum temperature for a sufficient duration to kill a desired percentage of pathogens located on and/or in the food products, the method comprising providing a pasteurization zone at a first operating parameter comprising a temperature of the pasteurization zone having a temperature setpoint between 55 ℃ [131 ° f ] and 70 ℃ [158 ° f ]. The method further includes conveying the food loaded onto the conveyor through a pasteurization zone at a second operating parameter including a speed of the conveyor that causes the food in the pasteurization zone to reach the setpoint temperature for a sufficient time to kill a desired percentage of pathogenic microorganisms that may be present on and/or in the food. The method further comprises measuring the temperature level in the pasteurization zone and/or the temperature of the food product. If the temperature in the pasteurization zone and/or the temperature of the food product deviates sufficiently from the setpoint temperature range so as not to kill a desired percentage of pathogens on and/or in the food product, a remedial procedure is initiated to kill a desired level of pathogens. The method further includes cooling or freezing the food product after it is conveyed through the pasteurization zone.

According to the invention, the temperature set point may be a wet bulb temperature, a dry bulb temperature or a dew point temperature.

According to the invention, the step of initiating the corrective procedure may comprise providing a notification that the temperature in the pasteurization chamber deviates from the set point temperature. Furthermore, a recommended temperature for setting the pasteurisation zone may be provided.

According to a further aspect of the invention, the step of initiating a corrective procedure may include automatically changing at least one operating parameter. Such operating parameters may include changing the temperature of the pasteurization zone, the speed of the conveyor, the loading level of the food product on the conveyor, and/or diverting food product from the conveyor prior to the cooling or freezing step.

The method of the present invention may further comprise providing moisture in the pasteurization zone, measuring a moisture level in the pasteurization zone, and adjusting the moisture level in the pasteurization zone if the moisture level is different than the preset amount.

According to a further aspect of the invention, the food product may be preheated before entering the pasteurization zone.

According to a further aspect of the invention, liquid refined from the food in the pasteurization zone can be collected. The liquid thus collected may be applied to the food product in said pasteurisation zone to assist pasteurisation of the food product. Alternatively, the collected liquid may be transported to a different location for storage or other use.

According to a further aspect of the invention, heated liquid may be supplied to the pasteurization zone and distributed over the food products to assist in heating and/or maintaining the temperature of the food products in the pasteurization zone.

The present invention also provides a system for continuous pasteurization of food products at low maximum temperatures for a sufficient duration to kill pathogens on and/or in the food products. The system comprises: a conveying system for conveying the food to be pasteurized; a low temperature pasteurization chamber through which the transport system passes; a pasteurization medium generator in fluid flow communication with the pasteurization chamber, the generator providing a pasteurization medium for heating and/or maintaining food products in the low temperature pasteurization chamber at a desired temperature; and a measuring system for measuring operational parameters of the system, said operational parameters comprising the speed of the conveyor, the temperature in the pasteurization chamber and/or the temperature of the pasteurization medium, and/or the temperature of the food product. The pasteurization system further comprises a control system for monitoring operating parameters of the pasteurization system, including the following parameters: (1) a speed of a conveyor in the pasteurization chamber to determine whether the conveyor is operating at a speed within a set point range that provides a desired residence time for food products in the pasteurization chamber to kill a desired percentage of pathogenic microorganisms present on and/or in the food products, (2) a temperature of a pasteurization medium supplied to the pasteurization chamber and/or a temperature in the pasteurization chamber to determine whether such temperature(s) are maintained at a temperature set point range of about 55 ℃ [131 ° f ] to about 70 ℃ [158 ° f ], and/or a temperature of the food product to determine whether the temperature of the food product reaches the set point temperature of the food product. The control system is operable to predict the change in temperature of the food product over time and/or simulate the lethality of pathogenic microorganisms, and based on such prediction and/or simulation, initiate a remedial procedure if necessary. The remedial procedure includes altering one or more of the operating parameters to kill a desired level of pathogens on and/or in the food product while maintaining a desired temperature for product quality by maintaining the core of the food product below the low maximum pasteurization temperature.