A method for preserving chicken quality based on segmented control

Abstract

This invention relates to the field of food processing technology, and more particularly to a method for preserving chicken quality based on segmented control. The method first pre-treats the chicken with a compound biological preservative solution, combined with ice storage and staged storage, effectively inhibiting microbial growth and enzyme activity in the chicken, delaying fat oxidation and protein degradation, and maintaining the chicken's excellent quality during long-term storage. During the staged storage process, key indicators are monitored in real-time or periodically, and a threshold comparison and stage switching mechanism is established to achieve precise dynamic control of the modified atmosphere packaging environment under dynamic deterioration of chicken quality. This invention, through segmented control, effectively prevents the loss of juices, color deterioration, and spoilage of chicken during storage, thereby maintaining its sensory and nutritional quality. Simultaneously, it significantly improves the gas utilization efficiency within the storage environment.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of food processing, and in particular to a chicken quality preservation processing method based on segmented regulation. BACKGROUND

[0002] Chicken is the most consumed poultry meat in the world, and its freshness and safety directly affect consumer health. However, chicken is susceptible to microbial contamination, fat oxidation, and protein denaturation during storage, leading to rapid quality decline. Traditional preservation methods cannot specifically inhibit the dominant factors at different stages of spoilage, such as microbial reproduction in the early stage and fat oxidation in the later stage.

[0003] Chinese Patent Publication No. CN114532394A discloses a method for acid removal and preservation of chicken. The related technical solution includes: after the live chicken inspection is completed, it enters the slaughter workshop, is soaked for disinfection, the whole body of the chicken is wet, and the chicken is loaded into the slaughter pit with the head facing down; the live chicken is slaughtered, bled, plucked, and eviscerated to obtain a chicken carcass; after the chicken carcass is treated, it is washed, soaked, and placed in a basket, and then sent to the first preservation warehouse for storage to reduce the center temperature to 3-7℃; then the chicken carcass is disinfected and placed in a basket for storage in the second preservation warehouse. The technical solution prolongs the storage period of chicken by combining cooling and disinfection, thereby prolonging the edible period of chilled meat. However, the technical solution adopts a relatively single and static preservation strategy, and fails to recognize that the main factors affecting the quality deterioration of chicken during the entire process from pretreatment to sale are dynamically changing. For example, in the early stage, microbial contamination and temperature control are dominant, in the middle stage, juice loss and oxidation are dominant, and in the later stage, color deterioration and specific cold-tolerant bacteria proliferation are dominant. Therefore, there is an urgent need for a comprehensive preservation processing method that can adapt to the dynamic changes in chicken quality and solve multiple quality deterioration problems in stages with focus, so as to achieve the dual goals of significantly prolonging the storage period and comprehensively improving the quality. SUMMARY

[0004] Therefore, the present application provides a chicken quality preservation processing method based on segmented regulation to solve the problem of being unable to accurately regulate the dynamic quality deterioration of chicken in the preservation process in stages in the prior art due to the relatively single and static preservation strategy.

[0005] To achieve the above-mentioned purpose, the present application provides a chicken quality preservation processing method based on segmented regulation, comprising:

[0006] The chicken is pretreated with a composite biological preservative solution, and the pretreated chicken is prepared for precooling within a first preset time period;

[0007] The chicken prepared for precooling is placed in a first ice temperature environment for ice storage treatment for a second preset time period.

[0008] The chicken meat after the ice storage treatment is subjected to dynamic modified atmosphere packaging, and sequentially subjected to staged storage in a second ice temperature environment, different gas combinations being used in each storage stage;

[0009] In the first storage stage, the carbon dioxide concentration and / or the oxygen concentration in the package are monitored in real time and compared with corresponding carbon dioxide concentration threshold values and / or oxygen concentration threshold values to determine whether to switch to the second storage stage for storage or continue storage in the first storage stage;

[0010] In the second storage stage, the microbial metabolite concentration and / or the visible droplet area ratio in the package are periodically monitored and compared with corresponding microbial metabolite concentration threshold values and / or visible droplet area ratio threshold values to determine the brightness value of the chicken meat;

[0011] Based on the comparison result of the brightness value and the brightness value threshold value, it is determined whether to switch to the third storage stage for storage or continue storage in the second storage stage;

[0012] In the third storage stage, the microbial metabolite concentration and / or the visible droplet area ratio in the package are periodically monitored and compared with corresponding microbial metabolite concentration threshold values and / or visible droplet area ratio threshold values to determine whether to continue storage in the third storage stage;

[0013] In the second storage stage, the gas proportion in the gas combination is adjusted according to the carbon dioxide concentration or the oxygen concentration; in the third storage stage, the gas proportion in the gas combination is adjusted according to the brightness value

[0014] Further, in the first storage stage, a first gas combination containing a first preset carbon dioxide concentration and a first preset nitrogen concentration is used, wherein the first preset carbon dioxide concentration is 70%±3%, and the first preset nitrogen concentration is 30%±3%;

[0015] In the second storage stage, a second gas combination containing a second preset carbon dioxide concentration, a second preset nitrogen concentration, and a first preset oxygen concentration is used, wherein the second preset carbon dioxide concentration is 55%±3%, the second preset nitrogen concentration is 15%±5%, and the first preset oxygen concentration is 30%±3%;

[0016] In the third storage stage, a third gas combination containing a third preset carbon dioxide concentration and a second preset oxygen concentration is used, wherein the third preset carbon dioxide concentration is 50%±3%, and the second preset oxygen concentration is 50%±3%.

[0017] Furthermore, during the first storage stage, based on the carbon dioxide concentration being less than or equal to the carbon dioxide concentration threshold, and / or the oxygen concentration being greater than the oxygen concentration threshold, it is determined that the first gas combination will be adjusted to the second gas combination and the concentration of the microbial metabolites and / or the proportion of the visible droplet area will be periodically monitored.

[0018] Based on the fact that the carbon dioxide concentration is greater than the carbon dioxide concentration threshold and / or the oxygen concentration is less than or equal to the oxygen concentration threshold, it is determined that storage will continue in the first storage stage and the carbon dioxide concentration and / or oxygen concentration will continue to be monitored in real time.

[0019] Furthermore, during the second storage stage, based on the fact that the concentration of microbial metabolites is less than or equal to the threshold of the concentration of microbial metabolites, and / or the proportion of visible droplet area is less than or equal to the threshold of the proportion of visible droplet area, it is determined that the chicken should continue to be stored in the second storage stage and the chicken should be periodically monitored to determine the brightness value.

[0020] Storage is stopped based on the fact that the concentration of microbial metabolites is greater than the concentration threshold of microbial metabolites, and / or the proportion of visible droplet area is greater than the proportion threshold of visible droplet area;

[0021] The microbial metabolites are hydrogen sulfide or trimethylamine.

[0022] Furthermore, during the second storage stage, based on the brightness value being less than or equal to the brightness value threshold, it is determined that storage will continue in the second storage stage and the concentration of microbial metabolites and / or the proportion of visible droplet area will continue to be monitored periodically.

[0023] Based on the fact that the brightness value is greater than the brightness value threshold, it is determined that the second gas combination will be adjusted to the third gas combination and the concentration of the microbial metabolites and / or the proportion of the visible droplet area will continue to be monitored periodically.

[0024] Furthermore, in the third storage stage, based on the fact that the concentration of microbial metabolites is less than or equal to the concentration threshold of microbial metabolites, and / or the visible droplet area ratio is less than or equal to the visible droplet area ratio threshold, it is determined that storage will continue in the third storage stage and monitoring of microbial metabolite concentration and / or visible droplet area ratio will continue.

[0025] Storage is stopped based on the concentration of the microbial metabolites being greater than the concentration threshold of the microbial metabolites, and / or the visible droplet area ratio being greater than the visible droplet area ratio threshold.

[0026] Furthermore, during the pretreatment process, the compound biological preservative solution is treated at a temperature of 2℃~4℃. After the treatment is completed, the chicken is sprayed or soaked for 60~120 seconds.

[0027] During the pre-cooling preparation process, the first preset time is set to 1 to 2 hours. After the chicken is pre-treated, the center temperature of the thickest part of the chicken is reduced to 0°C to 2°C within 1 to 2 hours.

[0028] Furthermore, during the refrigeration process, the first ice temperature is set to -2℃ to -1℃, and the second preset time is set to 1 to 3 hours. After the pre-cooling preparation is completed, the chicken is placed in an environment of -2℃ to -1℃ with an air flow rate of 0.5m / s to 1.5m / s for refrigeration for 1 to 3 hours.

[0029] Furthermore, during the phased storage process, the second ice temperature is set to -1℃ to 0℃. The chicken that has been ice-frozen is packed into a package with an adjustable gas composition ratio. After vacuuming, the first gas combination is filled in and sealed. The package is then placed in an environment of -1℃ to 0℃ for phased storage.

[0030] Furthermore, the composite biological preservative solution initially contains the following components at the following concentrations: 0.5%–1.5% nisin, 1%–3% tea polyphenols, and 1%–2% chitosan, with water as the solvent;

[0031] Before processing, the surface of the chicken is tested for bacterial colonies to determine the initial total bacterial count. The concentrations of nisin and tea polyphenols are increased based on the comparison between the initial total bacterial count and the preset initial total bacterial count. The increase in the concentrations of nisin and tea polyphenols is positively correlated with the initial total bacterial count.

[0032] Compared with existing technologies, the chicken quality preservation method based on segmented control of the present invention has the following advantages: First, the chicken is pretreated with a compound biological preservative solution and then frozen, followed by staged storage. This effectively inhibits the growth of microorganisms and enzyme activity in the chicken, delays fat oxidation and protein degradation, and allows the chicken to maintain excellent quality during long-term storage. During the staged storage process, key indicators such as carbon dioxide concentration, oxygen concentration, microbial metabolite concentration, visible droplet area ratio, and brightness value are monitored in real time or periodically to establish a threshold comparison and stage switching mechanism. This enables precise dynamic control of the specific, staged modified atmosphere packaging environment under dynamic deterioration of chicken quality, thereby effectively preventing the loss of chicken juice, color deterioration, and off-flavors, and maintaining the sensory and nutritional quality of the chicken. Furthermore, through staged modified atmosphere strategy and feedback control, excessive gas use is avoided, improving gas utilization efficiency while ensuring preservation effect.

[0033] Furthermore, this invention provides monitoring parameters for three storage stages, and compares them with corresponding thresholds in each of the three stages to determine the corresponding processing methods for each stage, including continuing storage in the current storage stage, entering the next storage stage in advance, or stopping storage in advance. The transition between stages is not based on the simple passage of time, but on a comprehensive evaluation based on real-time or periodic monitoring data to dynamically switch the gas combination of the three stages, thereby making targeted adjustments according to the physiological and microbial changes of chicken in different storage stages to achieve dynamic preservation and real-time adaptation.

[0034] Furthermore, before pretreatment, the present invention monitors the initial total bacterial count of the chicken and adjusts the concentration of nisin and tea polyphenols in the compound biological preservative solution based on the comparison between the initial total bacterial count and the preset initial total bacterial count, thereby achieving a precise improvement in the processing efficiency of the compound biological preservative solution. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the chicken quality preservation and processing system based on segmented control in this invention.

[0036] Figure 2 This is a flowchart illustrating the chicken quality preservation method based on segmented control in this invention. Figure 1 ;

[0037] Figure 3 This is a flowchart illustrating the chicken quality preservation method based on segmented control in this invention. Figure 2 ;

[0038] Figure 4 This is a schematic diagram of the phased storage process in this invention. Detailed Implementation

[0039] To make the objectives and advantages of the present invention clearer, the present invention will be further described below with reference to embodiments; it should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0040] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0041] It should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the term "connection" should be interpreted broadly. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0042] Please see Figure 1As shown, it is a schematic diagram of the chicken quality preservation and processing system based on segmented control in this embodiment. The system includes at least a pre-cooling preparation module, an ice storage module, a storage module, a monitoring module, an analysis module, and a control module. The pretreatment module is used to pretreat the chicken with a compound biological preservative solution and to pre-cool the pretreated chicken within a first preset time period. The ice storage module is connected to the pretreatment module and is used to place the pre-cooled chicken in a first ice-temperature environment for ice storage for a second preset time period. The storage module is connected to the ice storage module and is used to package the ice-stored chicken using a dynamic controlled atmosphere method and to store it in a second ice-temperature environment for staged storage. The monitoring module is connected to the storage module and is used to monitor the chicken packaging to determine the corresponding parameters in each storage stage. Specifically, in the first storage stage, it monitors the carbon dioxide concentration and / or oxygen concentration; in the second storage stage, it monitors the concentration of microbial metabolites and / or the proportion of visible droplets, as well as the brightness value; and in the third storage stage, it continues to monitor the concentration of microbial metabolites and / or the proportion of visible droplets. The analysis module is connected to the monitoring module and is used to analyze the results based on the comparison between the carbon dioxide concentration monitored in the first storage stage and the carbon dioxide concentration threshold Q0, and / or... The control module generates a first adjustment command based on the comparison result of oxygen concentration and oxygen concentration threshold, and generates a second or third adjustment command based on the comparison result of microbial metabolite concentration and microbial metabolite concentration threshold monitored in the second storage stage, and / or the comparison result of visible droplet area ratio and visible droplet area ratio threshold. It also generates a fourth adjustment command based on the comparison result of brightness value and brightness value threshold monitored in the second storage stage, and a fifth adjustment command based on the comparison result of microbial metabolite concentration and microbial metabolite concentration threshold monitored in the third storage stage, and / or the comparison result of visible droplet area ratio and visible droplet area ratio threshold. The control module is connected to the analysis module, the storage module, and the monitoring module respectively, to control the storage module to adjust the first gas combination to the second gas combination based on the first adjustment command, to control the monitoring module to monitor the brightness value based on the second adjustment command, to control the storage module to adjust the second gas combination to the third gas combination based on the third adjustment command, and to control the storage module to stop storage based on the fourth or fifth adjustment command.

[0043] In the second storage stage, the gas proportions in the gas combination are adjusted based on the carbon dioxide concentration or the oxygen concentration; in the third storage stage, the gas proportions in the gas combination are adjusted based on the brightness value. The first gas combination includes a first preset carbon dioxide concentration and a first preset nitrogen concentration; the second gas combination includes a second preset carbon dioxide concentration, a second preset nitrogen concentration, and a first preset oxygen concentration; and the third gas combination includes a third preset carbon dioxide concentration and a second preset oxygen concentration. When adjusting the first gas combination to the second gas combination, if the detected carbon dioxide concentration (less than or equal to a carbon dioxide concentration threshold) is smaller, or the detected oxygen concentration (greater than an oxygen concentration threshold) is larger, the proportion of the second preset carbon dioxide concentration in the second gas combination is larger, and the proportion of the first preset oxygen concentration is smaller. When adjusting the second gas combination to the third gas combination, if the detected brightness value (greater than a brightness value threshold) is larger, the proportion of the third preset carbon dioxide concentration in the third gas combination is larger, and the proportion of the second preset oxygen concentration is smaller.

[0044] Please see Figure 2 The diagram shown illustrates the process flow of the chicken quality preservation method based on segmented control in this embodiment. Figure 1 The process includes at least the following steps:

[0045] S1: The chicken is pretreated with a compound biological preservative solution and then pre-cooled within a first preset time period.

[0046] S2: Place the pre-cooled chicken in a first ice-temperature environment for a second preset duration of ice storage;

[0047] S3: The chicken meat that has undergone the ice-free treatment is dynamically modified atmosphere packaged and stored in stages in a second ice-temperature environment, with different gas combinations used in each storage stage.

[0048] S31: Enter the first storage stage and determine whether to enter the second storage stage;

[0049] S32: Enter the second storage stage and periodically monitor the brightness value;

[0050] S33: Determine whether to enter the third storage stage based on the brightness value;

[0051] S34: Entering the third storage stage;

[0052] S4: End of storage.

[0053] Please see Figure 3 The diagram shown illustrates the process flow of the chicken quality preservation method based on segmented control in this embodiment. Figure 2 Flowchart Figure 2The content is about Figure 4 To supplement step S3:

[0054] S31: During the first storage stage, the carbon dioxide concentration and / or oxygen concentration inside the packaging are monitored in real time and compared with the corresponding carbon dioxide concentration threshold and / or oxygen concentration threshold to determine whether to transfer to the second storage stage for storage or continue storage in the first storage stage.

[0055] S32: During the second storage stage, periodically monitor the concentration of microbial metabolites and / or the proportion of visible droplets in the packaging, and compare them with the corresponding thresholds for microbial metabolite concentration and / or the proportion of visible droplets to determine the brightness value of the chicken meat during periodic monitoring.

[0056] S33: Based on the comparison results between the brightness value and the brightness value threshold, determine whether to transfer to the third storage stage for storage or continue storage in the second storage stage;

[0057] S34: During the third storage stage, continue to periodically monitor the concentration of microbial metabolites and / or the percentage of visible droplets in the packaging, and compare them with the corresponding thresholds for microbial metabolite concentration and / or the percentage of visible droplets to determine whether to continue storage in the third storage stage.

[0058] Specifically, in the first storage stage, a first gas combination is used, comprising a first preset carbon dioxide concentration and a first preset nitrogen concentration, wherein the first preset carbon dioxide concentration is 70%±3% and the first preset nitrogen concentration is 30%±3%; in the second storage stage, a second gas combination is used, comprising a second preset carbon dioxide concentration, a second preset nitrogen concentration and a first preset oxygen concentration, wherein the second preset carbon dioxide concentration is 55%±3%, the second preset nitrogen concentration is 15%±5% and the first preset oxygen concentration is 30%±3%; in the third storage stage, a third gas combination is used, comprising a third preset carbon dioxide concentration and a second preset oxygen concentration, wherein the third preset carbon dioxide concentration is 50%±3% and the second preset oxygen concentration is 50%±3%.

[0059] In this embodiment, a carbon dioxide detector installed on the packaging continuously monitors carbon dioxide in the headspace gas inside the packaging, while an oxygen detector continuously monitors oxygen. A microbial metabolite concentration sensor periodically monitors the concentration R of microbial metabolites within the packaging. This sensor can detect hydrogen sulfide (H2S) and trimethylamine (TMA). For example, an electronic nose is used to analyze the headspace gas inside the packaging to obtain estimated hydrogen sulfide and TMA concentrations. An online machine vision system periodically acquires and analyzes images of the bottom of the packaging to determine the visible droplet area ratio U. A hyperspectral imaging system (scanning on a transmission line) or a fixed-point colorimeter periodically detects the chicken meat to determine the brightness value X. An ATP biofluorescence detector rapidly detects and determines the initial total bacterial count A on the surface of the chicken meat.

[0060] During the first storage stage, the deterioration of chicken product quality primarily stems from microbial spoilage. The large number and high activity of microorganisms enriched on the surface pose a major challenge during the shelf life. Therefore, the core of the preservation strategy should focus on effectively inhibiting microorganisms; color preservation can be considered a secondary consideration (or an acceptable sacrifice). Using a first gas combination of 70%±3% carbon dioxide and 30%±3% nitrogen to strongly inhibit microorganisms is the most efficient strategy. Real-time monitoring of carbon dioxide concentration Q and / or oxygen concentration W during the first storage stage allows for determination of the appropriate treatment based on the comparison between carbon dioxide concentration Q and the carbon dioxide concentration threshold Q0, and / or the comparison between oxygen concentration W and the oxygen concentration threshold W0. This includes continuing storage during the first stage, or adjusting the first gas combination to a second gas combination and periodically monitoring the concentration of microbial metabolites R and / or the proportion of visible droplets U. Active modified atmosphere packaging with variable gas ratios can be used to adjust the gas ratios during the chicken storage stage.

[0061] In the second storage stage, the main influencing factors are safety and spoilage rate. Therefore, it is necessary to periodically monitor the concentration of microbial metabolites (R) and / or the proportion of visible droplets (U). The appropriate treatment method can be determined based on the comparison between the concentration of microbial metabolites (R) and the microbial metabolite concentration threshold (R0), and / or the comparison between the proportion of visible droplets (U) and the visible droplet area threshold (U0). This includes continuing storage in the second storage stage while periodically monitoring the brightness value (X) of the chicken, or stopping storage. Furthermore, the appropriate treatment method can be determined based on the comparison between the brightness value (X) and the brightness value threshold (X0), including continuing storage in the second storage stage or transferring to the third storage stage.

[0062] During the third storage stage, the concentration of microbial metabolites R and / or the proportion of visible droplet area U are periodically monitored. Similarly, the corresponding treatment method can be determined based on the comparison results of the concentration of microbial metabolites R with the microbial metabolite concentration threshold R0 and / or the proportion of visible droplet area U with the visible droplet area proportion threshold U0, including: immediately stopping storage or continuing storage in the third storage stage until the end of the storage period.

[0063] In this embodiment, the duration of the first, second, and third storage stages can be exemplarily set to 7 days, 5 days, and 4 days, respectively. The system does not simply switch gases according to a fixed schedule, but rather automatically or manually initiates the switching procedure based on one or more signals monitored in real time, thereby using different gas combinations to suit the chicken meat at different quality stages during storage.

[0064] Please see ​ The diagram illustrates the phased storage process in this embodiment. Specifically, in the first storage stage, based on the carbon dioxide concentration being less than or equal to the carbon dioxide concentration threshold, and / or the oxygen concentration being greater than the oxygen concentration threshold, it is determined that the first gas combination will be adjusted to the second gas combination, and the concentration of microbial metabolites and / or the visible droplet area ratio will be periodically monitored; based on the carbon dioxide concentration being greater than the carbon dioxide concentration threshold, and / or the oxygen concentration being less than or equal to the oxygen concentration threshold, it is determined that storage in the first storage stage will continue, and the carbon dioxide concentration and / or oxygen concentration will continue to be monitored in real time.

[0065] In this embodiment, based on the experimental results of the effects of carbon dioxide and oxygen on microorganisms in chicken meat, the carbon dioxide concentration threshold Q0 = 62% and the oxygen concentration threshold W0 = 1.5% were pre-determined. The corresponding treatment method was determined by comparing the real-time monitored carbon dioxide concentration threshold Q0 and oxygen concentration threshold W0 with the corresponding thresholds.

[0066] When the monitored Q is less than or equal to Q0 and W is greater than W0, or when Q is less than or equal to Q0, or when W is greater than W0, it indicates that the goal of the first storage stage has been basically achieved. Under the dual inhibition of high carbon dioxide and low temperature, the growth curve of microorganisms has entered a plateau period, and the growth rate has slowed down. However, new major influencing factors have now emerged. At this time, continuing to maintain a high carbon dioxide environment will result in diminishing marginal benefits for antibacterial activity, and the negative impact on quality, color, and flavor will continue. For example, a high carbon dioxide environment will cause the pH value inside muscle cells to drop, approaching the isoelectric point of proteins, leading to a further decrease in the water-holding capacity of proteins and more severe juice loss. Therefore, it is necessary to change the storage strategy and switch from the first storage stage to the second storage stage. The first gas combination should be adjusted to a second gas combination of 55%±5% carbon dioxide, 15%±5% nitrogen, and 30%±5% oxygen. The oxygen content should be appropriately increased to restore and maintain the bright red color of the chicken and improve its water-holding capacity. The concentration of microbial metabolites R and / or the percentage of visible droplet area U should be monitored periodically.

[0067] When the monitored Q is greater than Q0 and W is less than or equal to W0, or when Q is greater than Q0, or when W is less than or equal to W0, the chicken continues to be stored in the first storage stage and the carbon dioxide concentration Q and oxygen concentration W are continuously monitored in real time. The carbon dioxide concentration Q and oxygen concentration W obtained from the real-time monitoring are continuously compared with the corresponding thresholds until the first storage stage is completely completed or the chicken is directly adjusted from the first storage stage to the second storage stage.

[0068] Specifically, during the second storage stage, based on the microbial metabolite concentration being less than or equal to the microbial metabolite concentration threshold, and / or the visible droplet area ratio being less than or equal to the visible droplet area ratio threshold, it is determined that storage in the second storage stage will continue and the chicken meat will be periodically monitored to determine the brightness value; based on the microbial metabolite concentration being greater than the microbial metabolite concentration threshold, and / or the visible droplet area ratio being greater than the visible droplet area ratio threshold, it is determined that storage will be stopped; wherein, the microbial metabolite is hydrogen sulfide or trimethylamine.

[0069] In this embodiment, if the microbial metabolite is hydrogen sulfide, the corresponding microbial metabolite concentration threshold R0 is actually the hydrogen sulfide response value R0. Based on the results of the chicken spoilage experiment conducted by Pseudomonas and other microorganisms, the pre-determined microbial metabolite concentration threshold R0 = 0.85V, and the pre-determined visible droplet area ratio U0 = 3%. If the microbial metabolite is trimethylamine, based on the results of the chicken spoilage experiment conducted by Proteobacteria and other microorganisms, the pre-determined microbial metabolite concentration threshold R0 = 3 mg / 100g, and the pre-determined visible droplet area ratio U0 = 3.5%. The corresponding treatment method is determined by comparing the periodically monitored microbial metabolite concentration R and visible droplet area ratio U with the corresponding thresholds.

[0070] When the monitored R is less than or equal to R0 and U is less than or equal to U0, or when R is less than or equal to R0, or when U is less than or equal to U0, it indicates that the chicken has not yet undergone significant spoilage in the second storage stage. At this time, it can continue to be stored in the second storage stage. Since oxygen has been added in the second storage stage, it is necessary to periodically monitor the brightness value X of the chicken. Based on the comparison result of the brightness value X and the brightness value threshold X, the change in the dryness or juice loss of the chicken surface can be determined, thereby determining whether to change the storage strategy.

[0071] When the monitored values ​​R are greater than R0 and U are greater than U0, or when R is greater than R0, or when U is greater than U0, it indicates that the chicken has begun to spoil significantly and there is a safety hazard. Storage must be stopped immediately.

[0072] Specifically, during the second storage stage, based on the brightness value being less than or equal to the brightness value threshold, it is determined to continue storage in the second storage stage and to continue periodically monitoring the concentration of microbial metabolites and / or the proportion of visible droplet area; based on the brightness value being greater than the brightness value threshold, it is determined to adjust the second gas combination to a third gas combination and to continue periodically monitoring the concentration of microbial metabolites and / or the proportion of visible droplet area.

[0073] In this embodiment, a brightness threshold X0 = 58 is predetermined through a consumer sensory evaluation experiment. The corresponding processing method is determined by comparing the brightness value X obtained from periodic monitoring with the brightness threshold X0.

[0074] When the monitored L is less than or equal to L0, it indicates that the chicken gloss has returned to normal. At this time, it can continue to be stored in the second storage stage, and the concentration of microbial metabolites R and / or the proportion of visible droplet area U should continue to be monitored periodically. Then, R and / or U should be compared with the corresponding thresholds to determine the subsequent treatment method.

[0075] When the monitored L is greater than L0, it indicates that the chicken surface is excessively dry or has lost juices, resulting in abnormal luster and a decline in marketability. At this time, it is necessary to change the storage strategy and directly switch from the second storage stage to the third storage stage. The second gas combination should be adjusted to use a third gas combination of 50%±5% carbon dioxide and 50%±5% oxygen to further increase the oxygen content, so as to improve the appearance of the chicken while retaining the basic antibacterial ability. Continue to periodically monitor the concentration of microbial metabolites R and / or the proportion of visible droplet area U, and then continue to compare R and / or U with the corresponding thresholds to determine the subsequent treatment method.

[0076] Specifically, in the third storage stage, based on the microbial metabolite concentration being less than or equal to the microbial metabolite concentration threshold, and / or the visible droplet area ratio being less than or equal to the visible droplet area ratio threshold, it is determined that storage in the third storage stage will continue and the microbial metabolite concentration and / or the visible droplet area ratio will continue to be monitored; based on the microbial metabolite concentration being greater than the microbial metabolite concentration threshold, and / or the visible droplet area ratio being greater than the visible droplet area ratio threshold, it is determined that storage will be stopped.

[0077] In this embodiment, during the third storage stage, since the oxygen concentration W has reached a relatively high level, surface drying or juice loss of the chicken is no longer the main influencing factor. The main influencing factor at this point is that the significant increase in oxygen content accelerates the spoilage process of the chicken. Therefore, the concentration of microbial metabolites R and / or the proportion of visible droplet area U are monitored, and then R and / or U are compared with corresponding thresholds to determine the corresponding treatment method.

[0078] When R is less than or equal to R0 and U is less than or equal to U0, or when R is less than or equal to R0, or when U is less than or equal to U0, it indicates that the chicken has not yet reached the preset safety hazard standard. At this time, it can continue to be stored in the third storage stage, and R and / or U can continue to be monitored until the end of the storage period.

[0079] When R is greater than R0 and U is greater than U0, or when R is greater than R0, or when U is greater than U0, it indicates that there is a safety hazard in the chicken, and storage should be stopped at this time.

[0080] Specifically, during the pretreatment process, the composite biological preservative solution is treated at a temperature of 2℃ to 4℃. After the treatment is completed, the chicken is sprayed or soaked for 60 to 120 seconds. During the pre-cooling preparation process, the first preset time is set to 1 to 2 hours. After the pretreatment of the chicken is completed, the center temperature of the thickest part of the chicken is reduced to 0℃ to 2℃ within 1 to 2 hours.

[0081] During the refrigeration process, the first ice temperature is set to -2℃ to -1℃, and the second preset time is set to 1 to 3 hours. After the pre-cooling preparation is completed, the chicken is placed in an environment of -2℃ to -1℃ and an air flow rate of 0.5m / s to 1.5m / s for refrigeration for 1 to 3 hours.

[0082] The compound biological preservative solution initially contains the following components at the following concentrations: 0.5%–1.5% nisin, 1%–3% tea polyphenols, and 1%–2% chitosan, with water as the solvent. Before treatment, the surface of the chicken is tested for bacterial colonies to determine the initial total bacterial count. Based on the comparison between the initial total bacterial count and the preset initial total bacterial count, the concentrations of nisin and tea polyphenols are increased. The increase in the concentrations of nisin and tea polyphenols is positively correlated with the initial total bacterial count.

[0083] In this embodiment, based on the regular and repeated sampling and testing of chicken samples, the normal distribution range of the total bacterial count is calculated, and a preset initial total bacterial count F0 is pre-determined. To more accurately determine the increase in the concentrations of nisin and tea polyphenols, the preset initial total bacterial count F0 can be divided into a first preset initial total bacterial count F1 and a second preset initial total bacterial count F2. For example, F1 is set to 1.5 × 10⁻⁶. 4 CFU / g, F2=3.5×10 4 CFU / g; the original nisin concentration was 0.8%, and the original tea polyphenol concentration was 1.5%; exemplarily, the following adjustments were made based on the comparison results of the initial total colony count F with F1 and F2:

[0084] If F is less than or equal to F1, then the original nisin and tea polyphenol concentrations will be maintained. If F is greater than F1 and less than or equal to F2, then the original nisin concentration will be increased by 20%, and the original tea polyphenol concentration by 25%. If F is greater than F2, then the original nisin concentration will be increased by 40%, and the original tea polyphenol concentration by 55%. It should be noted that the concentration increase can also be set to other values, and the increased nisin and tea polyphenol concentrations must not exceed the original concentration range.

[0085] To better illustrate the process of processing chicken using segmented control, the present invention will be further described below with reference to specific embodiments.

[0086] Example 1: A compound biological preservative solution was prepared, comprising 0.5% nisin and 1% tea polyphenols, with water as the solvent. The compound biological preservative solution was pre-cooled to 4°C, and then sprayed onto the chicken to be stored for 60 seconds. The sprayed chicken was then refrigerated for 1 hour, reducing the center temperature of the thickest part of the chicken to 2°C. The pre-treated chicken was then placed in an environment of -1°C with an air velocity of 0.5 m / s for 1 hour of refrigeration. The refrigerated chicken was then placed in an environment of 0°C for packaging and sealing, and then stored in stages. In the first storage stage, the first gas combination consisted of 70% carbon dioxide and 30% nitrogen.

[0087] During the first storage stage, when the carbon dioxide concentration Q=58% and the oxygen concentration W=2.5% are monitored in real time, the storage stage is transitioned to the second storage stage. The first gas combination is adjusted to the second gas combination, which consists of a carbon dioxide concentration of 55%, a nitrogen concentration of 15%, and an oxygen concentration of 30%.

[0088] During the second storage stage, the concentration of microbial metabolites corresponding to hydrogen sulfide was monitored to be R = 13 mg / m³. 3 If the visible droplet area accounts for 4% of the total area, storage should be stopped immediately.

[0089] Example 2: A compound biological preservative solution was prepared, comprising 1.5% nisin and 3% tea polyphenols, with water as the solvent. The compound biological preservative solution was pre-cooled to 2°C, and then the chicken to be stored was immersed in it for 120 seconds. The immersed chicken was then refrigerated for 2 hours until the center temperature of the thickest part of the chicken dropped to 0°C. The pre-treated chicken was then placed in an environment of -2°C with an air flow rate of 1.5 m / s for 3 hours of refrigeration. The refrigerated chicken was then placed in an environment of -1°C for packaging and sealing, and then stored in stages. In the first storage stage, the first gas combination was 70% carbon dioxide and 30% nitrogen.

[0090] During the first storage stage, when the carbon dioxide concentration Q=60% and the oxygen concentration W=2% are monitored in real time, the storage stage is transitioned to the second storage stage. The first gas combination is adjusted to the second gas combination, which consists of a carbon dioxide concentration of 50%, a nitrogen concentration of 15%, and an oxygen concentration of 35%.

[0091] During the second storage phase, the concentration of microbial metabolites corresponding to hydrogen sulfide was periodically monitored, with R = 8 mg / m³. 3If the visible droplet area ratio U = 2.5%, then continue storage in the second storage stage and periodically monitor the brightness value X; if the brightness value X = 62 is detected, the second gas combination is adjusted to the third gas combination, wherein the third gas combination is 50% carbon dioxide concentration and 50% oxygen concentration.

[0092] During the third storage stage, the concentration of microbial metabolites was periodically monitored to be R = 11 mg / m³. 3 When the visible droplet area accounts for 3.2% of the total area, storage should be stopped immediately.

[0093] Example 3: Adjust the compound biological preservative solution, wherein the concentration components are 1% nisin and 2.5% tea polyphenols, and the solvent is water; pre-cool the compound biological preservative solution to 2°C, then marinate the chicken to be stored for 120 seconds, and then refrigerate the marinated chicken for 1 hour so that the center temperature of the thickest part of the chicken drops to 0°C; then place the pretreated chicken in an environment of -1°C and an air flow rate of 1.5m / s for 2 hours of ice storage; then place the ice-stored chicken in an environment of -1°C for packaging and sealing and staged storage, wherein the first gas combination is 73% carbon dioxide concentration and 27% nitrogen concentration.

[0094] During the first storage stage, when the carbon dioxide concentration Q=58% and the oxygen concentration W=2.3% are monitored in real time, the storage stage is transitioned to the second storage stage. The first gas combination is adjusted to the second gas combination, which consists of a carbon dioxide concentration of 55%, a nitrogen concentration of 13%, and an oxygen concentration of 32%.

[0095] During the second storage phase, the concentration of microbial metabolites corresponding to hydrogen sulfide was periodically monitored to be R = 8.5 mg / m³. 3 If the visible droplet area ratio U = 2.7%, continue storage in the second storage stage and periodically monitor the brightness value X; if the brightness value X = 49, continue storage in the second storage stage and continue periodically monitoring the microbial metabolite concentration R and / or the visible droplet area ratio U; if subsequent periodic monitoring shows that the microbial metabolite concentration R is less than or equal to 10 mg / m³, continue storage in the second storage stage. 3 If the visible droplet area ratio U is less than or equal to 3%, then storage will continue in the second storage stage until the third storage stage begins.

[0096] Upon entering the third storage stage, the second gas mixture was adjusted to the third gas mixture, which consisted of 48% carbon dioxide and 52% oxygen. During the third storage stage, the concentration of microbial metabolites, R = 9 mg / m³, was periodically monitored. 3 If the visible droplet area ratio is U=2.9%, then storage will continue in the third storage stage until the end of the storage period.

[0097] Control group Example 4: The difference between it and Example 1 is that the first gas combination is still used in the second storage stage, and the rest is the same as Example 1.

[0098] Control group Example 5: The difference between it and Example 2 is that when the carbon dioxide concentration Q=60% and the oxygen concentration W=2% were monitored in real time, it was still stored in the first storage stage, and the rest was the same as Example 2.

[0099] Control group Example 6: The difference between it and Example 3 is that the second gas combination is still used when entering the third storage stage, and the rest is the same as Example 3.

[0100] Testing and evaluation methods:

[0101] Total microbial count: According to GB 4789.2-2022 "National Food Safety Standard for Microbiological Examination of Food - Determination of Total Colony Count", aseptically weigh 25g of sample and homogenize it in 225mL of sterile physiological saline to prepare a 1:10 sample homogenate, and then serially dilute it to the appropriate concentration; pipette 1mL of sample solution into a sterile Petri dish, pour in plate counting agar medium cooled to 46℃, mix well and allow it to solidify, then invert it in a constant temperature incubator at 36±1℃ for 48±2h; count typical colonies and report the results, in units of CFU / g.

[0102] TBARS value: According to GB 5009.181-2016 "National Food Safety Standard - Determination of Malondialdehyde in Food", 5g of minced meat sample was weighed, and 25mL of 7.5% trichloroacetic acid solution (containing 0.1% EDTA) was added for homogenization extraction. After filtration, 5mL of the filtrate was mixed with 5mL of 0.02mol / L thiobarbituric acid aqueous solution. After boiling in a water bath for 40min and cooling, the absorbance was measured at a wavelength of 532nm. At the same time, a standard curve for malondialdehyde was prepared. The result was calculated based on the standard curve and expressed as milligrams of malondialdehyde per kilogram of sample, in mg / kg.

[0103] Juice loss rate: Referring to NY / T 2793-2015 "Determination of juice loss rate in meat and meat products", at the end of the storage period, take out the meat sample, absorb the liquid adhering to the surface with filter paper, and accurately weigh the mass after storage (M2); compare the current weight with the initial weight of the meat sample before packaging and sealing (M1), and calculate the juice loss rate according to the formula ((M1-M2) / M1×100%), expressed as a percentage (%).

[0104] Color L value: According to GB / T 22295-2008 "Determination of color of transparent liquids", the brightness of the surface of chicken breast was directly measured using a calibrated colorimeter with a D65 light source and a 10° observation angle. Three different sites were measured in parallel for each sample, and the average value was taken. The result is expressed as CIEL value (brightness value).

[0105] Sensory evaluation: In accordance with GB / T 22210-2024 "Sensory Evaluation Standard for Meat and Meat Products", a sensory evaluation team of no less than 7 trained evaluators shall be formed; under standard lighting and environment, the color, odor, texture and overall acceptability of the meat samples shall be comprehensively evaluated; after weighted calculation of each indicator, a score of 10 shall be used (1 point indicates extremely unacceptable, and 10 points indicates excellent quality), and the final result shall be the arithmetic mean of the evaluators' scores.

[0106] Please see the table below for specific data.

[0107] Table 1. Experimental results of Examples 1-6

[0108]

[0109] As can be seen from Table 1:

[0110] The complete implementation of this invention demonstrates significant comprehensive performance advantages: In terms of microbial inhibition, Examples 1-3, through the synergistic effect of pretreatment with a compound biological preservative and refrigeration, form an effective protective layer on the surface of the chicken meat. Combined with the dynamic and precise control of staged modified atmosphere packaging, the total number of microorganisms is maintained at 10. 4 Low levels below CFU / g. In contrast, Control Group Example 4 continued to use the first gas combination when it should have entered the second storage stage, and the prolonged high concentration of carbon dioxide environment led to tissue damage, a significant increase in juice loss, and accelerated microbial growth; Control Group Example 5 failed to switch storage stages in time when the monitoring indicators reached the threshold, and the gas environment was mismatched with the actual state of the chicken, with an increased TBARS value indicating aggravated fat oxidation; Control Group Example 6 did not adjust the gas combination after entering the third storage stage, and insufficient oxygen concentration led to color deterioration and a significant decrease in sensory scores.

[0111] Regarding quality maintenance, the juice loss rate of Examples 1-3 was less than 2.5%, the color L value remained above 66, and the sensory score reached above 8.9, proving that the present invention can effectively maintain the freshness of chicken. In contrast, all control groups showed significant quality decline: juice loss rate exceeded 3.9%, color L value was below 62.1, and sensory score was below 7.1. Particularly in control groups Example 4 and Example 5, the total number of microorganisms approached 10 due to the failure of gas environment control. 5 The CFU / g level seriously affects food safety.

[0112] In summary, in Examples 1-3 and the control group Examples 4-6, Examples 1-3, which fully implemented the process of the present invention, all showed excellent and stable preservation effects, which were significantly better than those of the control groups, thus confirming the key role of the segmented dynamic control strategy in the preservation of chicken quality.

[0113] It is understood that no specific limitation is made to any preset parameter or critical parameter in the embodiments of the present invention, and the above values ​​are not limited thereto. Those skilled in the art can make corresponding adjustments to the preset parameters or critical parameters according to actual needs, analysis of historical data, or equipment usage.

[0114] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of the present invention.

Claims

1. A chicken quality preservation treatment method based on segmented regulation, characterized by, The method comprises the following steps: The chicken is pretreated with a composite biological preservative solution, and then pre-cooled for a first preset time; The chicken after the pre-cooling is placed in a first ice temperature environment for ice storage for a second preset time; The chicken after the ice storage is dynamically modified atmosphere packaged, and sequentially stored in different stages in a second ice temperature environment, and different gas combinations are used in each storage stage; wherein the processing mode corresponding to each stage is determined, including continuing to store in the current storage stage, or entering the next storage stage in advance, or stopping storage in advance; Based on the real-time or periodic monitoring data combination, the three-stage gas combination is dynamically switched for comprehensive evaluation, so as to adjust the physiological and microbial changes of the chicken in different storage stages, realize dynamic preservation and real-time adaptation; In the first storage stage, the carbon dioxide concentration and / or oxygen concentration in the package are monitored in real time, and compared with the corresponding carbon dioxide concentration threshold and / or oxygen concentration threshold to determine whether to enter the second storage stage for storage or continue to store in the first storage stage; In the second storage stage, the microbial metabolite concentration and / or visible droplet area ratio in the package are periodically monitored, and compared with the corresponding microbial metabolite concentration threshold and / or visible droplet area ratio threshold to determine the periodic monitoring of the brightness value of the chicken; wherein, based on the microbial metabolite concentration being less than or equal to the microbial metabolite concentration threshold, and / or the visible droplet area ratio being less than or equal to the visible droplet area ratio threshold, it is determined to continue to store in the second storage stage and periodically monitor the chicken to determine the brightness value; Based on the microbial metabolite concentration being greater than the microbial metabolite concentration threshold, and / or the visible droplet area ratio being greater than the visible droplet area ratio threshold, it is determined to stop storage; Based on the comparison result of the brightness value and the brightness value threshold, it is determined to enter the third storage stage for storage or continue to store in the second storage stage; In the third storage stage, the microbial metabolite concentration and / or visible droplet area ratio in the package are periodically monitored, and compared with the corresponding microbial metabolite concentration threshold and / or visible droplet area ratio threshold to determine whether to continue to store in the third storage stage; In the first storage stage, based on the carbon dioxide concentration being less than or equal to the carbon dioxide concentration threshold, and / or the oxygen concentration being greater than the oxygen concentration threshold, the first gas combination is adjusted to the second gas combination, and the microbial metabolite concentration and / or the visible droplet area ratio are periodically monitored; Based on the carbon dioxide concentration being greater than the carbon dioxide concentration threshold, and / or the oxygen concentration being less than or equal to the oxygen concentration threshold, it is determined to continue to store in the first storage stage and continue to monitor the carbon dioxide concentration and / or the oxygen concentration in real time; The proportion of the gas in the gas combination in the second storage stage is adjusted according to the carbon dioxide concentration or the oxygen concentration, and the proportion of the gas in the gas combination in the third storage stage is adjusted according to the brightness value. The microbial metabolite is hydrogen sulfide or trimethylamine.

2. The chicken quality preservation treatment method based on the segmented regulation according to claim 1, characterized by, In the first storage stage, a first gas combination containing a first preset carbon dioxide concentration and a first preset nitrogen concentration is used, wherein the first preset carbon dioxide concentration is 70%±3%, and the first preset nitrogen concentration is 30%±3%. In the second storage stage, a second gas combination containing a second preset carbon dioxide concentration, a second preset nitrogen concentration, and a first preset oxygen concentration is used, wherein the second preset carbon dioxide concentration is 55%±3%, the second preset nitrogen concentration is 15%±5%, and the first preset oxygen concentration is 30%±3%. In the third storage stage, a third gas combination containing a third preset carbon dioxide concentration and a second preset oxygen concentration is used, wherein the third preset carbon dioxide concentration is 50%±3%, and the second preset oxygen concentration is 50%±3%.

3. The chicken quality preservation treatment method based on the segmented regulation according to claim 2, characterized by, In the second storage stage, based on the brightness value being less than or equal to the brightness value threshold, it is determined to continue storing in the second storage stage and to continue periodically monitoring the microbial metabolite concentration and / or the visible droplet area proportion; Based on the brightness value being greater than the brightness value threshold, it is determined to adjust the second gas combination to the third gas combination and to continue periodically monitoring the microbial metabolite concentration and / or the visible droplet area proportion.

4. The chicken quality preserving treatment method based on the segmented regulation according to claim 2, characterized by, In the third storage stage, based on the microbial metabolite concentration being less than or equal to the microbial metabolite concentration threshold, and / or the visible droplet area proportion being less than or equal to the visible droplet area proportion threshold, it is determined to continue storing in the third storage stage and to continue monitoring the microbial metabolite concentration and / or the visible droplet area proportion; Based on the microbial metabolite concentration being greater than the microbial metabolite concentration threshold, and / or the visible droplet area proportion being greater than the visible droplet area proportion threshold, it is determined to stop storing.

5. The chicken quality preservation treatment method based on the segmented regulation according to claim 1, characterized by, In the pretreatment process, the composite biological preservative solution is treated at a temperature of 2-4°C, and after the treatment is completed, the chicken is sprayed or immersed for 60-120 seconds. In the precooling preparation process, the first preset time period is set to 1-2 hours, and after the pretreatment of the chicken is completed, the center temperature of the thickest part of the chicken is reduced to 0-2°C within 1-2 hours.

6. The chicken quality preservation treatment method based on the segmented regulation according to claim 1, characterized by, In the ice storage treatment process, the first ice temperature is set to -2 to -1°C, and the second preset time period is set to 1-3 hours, and after the precooling preparation is completed, the chicken is placed in an environment with an air flow rate of 0.5-1.5 m / s at -2 to -1°C for 1-3 hours of ice storage.

7. The chicken quality preservation treatment method based on the segmented regulation according to claim 2, characterized by, In the staged storage process, the second ice temperature is set to -1 to 0°C, the chicken after the ice storage treatment is packed in a package with adjustable gas composition, vacuumized, filled with the first gas combination, and sealed, and the package is stored in an environment at -1 to 0°C for staged storage.

8. The segment-based regulation-based chicken quality preservation treatment method according to claim 1, characterized by, The complex biological preservative solution initially comprises the following components: 0.5%-1.5% of nisin, 1%-3% of tea polyphenol, and 1%-2% of chitosan, and the solvent is water; Before the treatment, the total number of initial colonies on the surface of the chicken is detected, and the concentration of the nisin and the tea polyphenol is increased according to the comparison result of the total number of initial colonies and the preset total number of initial colonies, wherein the concentration of the nisin and the tea polyphenol is positively correlated with the total number of initial colonies.

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