A method for cleaning, sterilizing and preserving eggs and duck eggs

Abstract

The application provides a chicken egg and duck egg integrated cleaning, sterilization and preservation treatment method, and belongs to the field of poultry egg processing technology, and comprises the following steps: S1, calculating an egg type discrimination index and assigning an egg type mark, calculating an eggshell surface area and a pre-coating film thickness, and applying a water-soluble sacrificial protective film; S2, calling a disinfection reference benchmark according to the egg type mark, calculating a cleaning time and a disinfection effect index, performing warm water spray cleaning, then performing sodium hypochlorite hot water immersion sterilization, and then performing air knife drying; S3, dissolving and removing the sacrificial protective film to expose a natural outer film, calculating a comprehensive drying index, and performing secondary drying and re-judging for unqualified products; and S4, calculating a preservation coating liquid volume, and applying the preservation coating on the surface of an eggshell with an intact natural outer film. The application avoids damage to the natural outer film caused by cleaning, realizes integrated processing of chicken eggs and duck eggs in the same line, quantitative determination and closed-loop control of disinfection and dryness, and significantly improves coating uniformity and preservation effect.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of poultry egg processing, in particular to a method for integrated cleaning, sterilization and preservation of chicken eggs and duck eggs. BACKGROUND

[0002] After the production of poultry eggs, the surface often carries feces, feathers, feed powder and other dirt, which is easy to breed pathogenic bacteria such as Salmonella and Escherichia coli. In order to ensure food safety, poultry eggs need to be cleaned and sterilized before they are put on the market to remove dirt and microorganisms on the surface of the eggshell. However, fresh poultry eggs have a natural protective film on the outside of the eggshell, which can prevent bacteria from entering the egg and slow down water loss. This natural protective film is destroyed by water cleaning, and the poultry eggs without protection have a shelf life of only 24 hours. Therefore, a method can be constructed to fundamentally avoid the destruction of the natural protective film of the eggshell during the cleaning process, so that uniform coating can be carried out on the eggshell with intact natural protective film, and the real integration of chicken eggs and duck eggs on the same production line can be realized.

[0003] In the prior art, a patent with publication number CN115299491A discloses a cleaning poultry egg biomimetic preservative film coating and its preparation method and application. The technology includes: 1-10% food-grade polyacrylic acid sodium; 0.5 ‰-5 ‰ cationic food-grade polyacrylamide; 0.01 ‰-0.07 ‰ food-grade preservative; the balance is water. The cleaning poultry egg biomimetic preservative film coating can be used as a preservative film for cleaning eggs. This film not only effectively seals the pores and cracks on the surface of the eggshell, preventing the loss of gas and water in the eggshell, but also to some extent prevents the invasion of bacteria. The film also has better structural strength than the natural ecological film and will not be easily worn out, providing better protection for poultry eggs and effectively reducing the breakage rate of poultry eggs during production, processing, transportation and sales. In addition, the preservative component in the preservative film coating can effectively inhibit bacteria, so that the preservative film can achieve better preservation effect.

[0004] But in the prior art, the existing egg cleaning process technology follows the route of cleaning and destroying the protective layer, and then coating a film to compensate for the loss. The natural outer membrane on the surface of fresh poultry eggs is destroyed once it is washed with water, and the protected poultry eggs will only have a shelf life of 24 hours if no measures are taken. The coating is carried out on the surface of the damaged eggshell, and the natural outer membrane is destroyed. The surface roughness, surface energy and other parameters of the eggshell surface have significant individual differences, resulting in uneven coating. Due to the difference in eggshell structure, chicken eggs and duck eggs need to be set separately for cleaning and coating parameters. In the existing equipment, duck eggs use hot water spray egg washing machine, and chicken eggs use hot roller wet egg cleaning machine, which requires two different processes and equipment, and it is difficult to truly integrate the processing. In addition, the disinfection effect is judged by experience, and there is a lack of quantitative judgment based on effective chlorine concentration, temperature and contact time; the drying degree before coating depends on fixed drying time, and there is a lack of quantitative judgment of each egg; unqualified products lack closed-loop processing of secondary drying. The parameters of each process are independent of each other, and no quantitative transmission from pre-coating to coating is formed.

[0005] The above information disclosed in the background section is only intended to enhance the understanding of the background of the present disclosure, and therefore it can include information that does not constitute the prior art known to those of ordinary skill in the art. SUMMARY

[0006] The purpose of the present application is to provide a chicken egg and duck egg integrated cleaning and sterilization preservation processing method to solve the problems raised in the background art. The present application protects the natural outer membrane by pre-coating a sacrificial protective film, and the uniformity of the film after removing the film is improved; the egg species discrimination index realizes the integration of chicken eggs and duck eggs on the same line; the disinfection effect index quantitatively determines the disinfection, avoiding insufficient or excessive disinfection; the comprehensive drying index determines the drying degree of each egg, and the unqualified products are diverted for secondary drying and re-determination; each parameter can be directly measured and form a quantitative transmission chain, realizing accurate control of the whole process; uniform coating on the intact natural outer membrane effectively prolongs the shelf life of poultry eggs.

[0007] To achieve the above-mentioned purpose, the present application provides the following technical scheme: A chicken egg and duck egg integrated cleaning and sterilization preservation processing method, comprising: S1: Collecting the initial weight, eggshell color reflectance, major axis and minor axis of the poultry eggs, calculating the egg species discrimination index, determining the poultry eggs as chicken eggs or duck eggs and giving an egg species label; calculating the eggshell surface area according to the major axis, minor axis and egg shape coefficient; applying a water-soluble sacrificial protective film on the eggshell surface; calculating the pre-coating film thickness according to the film layer mass after pre-coating drying, the density of the sacrificial protective film and the eggshell surface area; S2: Calculating the cleaning time according to the pre-coating film thickness and the minimum sacrificial protective film thickness allowed to remain; automatically calling the disinfection reference benchmark corresponding to the egg species according to the egg species label, calculating the disinfection effect index according to the effective chlorine concentration of the disinfectant, the disinfectant temperature and the disinfection contact time, and determining whether the disinfection is qualified; using warm water spray cleaning, then hot water immersion sterilization with sodium hypochlorite, and air knife drying; S3: Dissolve and remove the sacrificial protective membrane to expose the natural outer membrane of the eggshell, and dry it with an air knife; measure the weight of the egg, the surface humidity of the eggshell, and the surface temperature of the eggshell after demeabilization and air drying; calculate the comprehensive drying index based on the initial weight, the weight after demeabilization and air drying, the surface humidity of the eggshell, and the surface temperature of the eggshell, and compare it with the preset drying threshold for the corresponding egg type; if qualified, proceed to S4; if unqualified, it is diverted to the secondary drying channel; calculate the secondary drying time based on the current weight loss rate, the target weight loss rate, the correlation coefficient of the egg type, the secondary drying hot air temperature, and the secondary drying wind speed, and perform secondary drying; after secondary drying, re-evaluate; if qualified, proceed to S4; if still unqualified, exit the production line; S4: Calculate the volume of preservative coating liquid required for a single poultry egg based on the eggshell surface area, the target preservative coating thickness, and the volume fraction of film-forming substances in the coating liquid. Apply the preservative coating to the eggshell surface with intact natural outer membrane and dry and cure it with hot air.

[0008] Furthermore, the egg breed discrimination index is calculated using the following formula: Where: K is the egg species discrimination index; This is the initial weight; Weight reference value The reflectance of the eggshell color; This is a reference value for color reflectance; It is the major axis; It is the minor axis; For weight; For color items; For shape items; , , These are the weight coefficients for the weight, color, and shape items, respectively.

[0009] Furthermore, the egg species discrimination index With preset threshold Comparison; the preset threshold The critical value for the egg species discrimination index used to distinguish between chicken eggs and duck eggs is determined by measuring a large number of known chicken and duck eggs respectively. Values, statistically analyzing the two types of eggs Value distribution, select the boundary point that minimizes the false positive rate as ;when The current egg is determined to be a duck egg and an egg species label is assigned. ,when The current egg is determined to be a chicken egg and an egg species label is assigned. .

[0010] Further, the eggshell surface area is calculated by the following formula: Wherein: A is the eggshell surface area; B is the egg shape coefficient; The pre-coating film thickness is calculated by the following formula: Wherein: T is the pre-coating film thickness; W is the pre-coating film layer mass after drying; D is the sacrificial protective film density.

[0011] Further, the cleaning time calculation formula is: Wherein: T is the cleaning time; Dmin is the minimum sacrificial protective film thickness; K is the cleaning dissolution rate coefficient; T is the cleaning water temperature; The disinfection effect index is calculated by the following formula: Wherein: I is the disinfection effect index; C is the disinfectant effective chlorine concentration; T is the disinfectant temperature; t is the disinfection contact time; C0 is the effective chlorine concentration reference value; T0 is the disinfectant temperature reference value; t0 is the disinfection contact time reference value.

[0012] Further, the control system determines the cleaning time according to the output pre-coating film thickness and the preset minimum residual sacrificial protective film thickness after cleaning, and controls the spraying device to clean the eggs with warm water; during the cleaning process, the surface layer of the sacrificial protective film gradually dissolves and peels off carrying dirt, and the residual sacrificial protective film is still retained on the eggshell surface at the end of the cleaning; the disinfection effect index is used to determine whether the disinfection effect of the sodium hypochlorite hot water immersion sterilization in S2 meets the standard: comparing the disinfection effect index with the preset qualified value; when the disinfection effect index reaches the preset qualified value, it is determined that the disinfection is qualified, and the eggs are allowed to enter S3; when the disinfection effect index is lower than the preset qualified value, it is determined that the disinfection is unqualified, and the control system alarms and adjusts the disinfection parameters until the qualified.

[0013] Further, the comprehensive drying index calculation formula is: Among them: is the comprehensive drying index; is the initial weight; is the weight after film removal and air drying; is the eggshell surface humidity; is the surface humidity reference value; is the eggshell surface temperature; is the surface temperature reference value; is the weight loss rate; is the surface humidity deviation rate; is the surface temperature ratio; , , respectively, the weight loss rate, the surface humidity deviation rate, and the surface temperature ratio are weight coefficients.

[0014] Further, the secondary drying time is calculated by the following formula: Among them: is the time required for secondary drying; is the egg type correlation coefficient; is the target weight loss rate; is the current weight loss rate; is the secondary drying hot air temperature; is the secondary drying air speed.

[0015] Further, the comprehensive drying index is used for judging the drying degree of each egg after air-drying after removing the membrane in S3; the control system compares the calculated comprehensive drying index with the preset drying threshold of the corresponding egg, and when the preset drying threshold is reached, it is determined that the drying is qualified and is allowed to enter S4 coating; when the comprehensive drying index is lower than the preset drying threshold, it is determined that it is unqualified and triggers the shunting, and the eggs are guided into the secondary drying channel; the secondary drying time is used for controlling the hot air drying duration of the eggs in the secondary drying channel, and after the secondary drying is completed, the eggs are re-judged by the comprehensive drying index, the qualified ones enter S4, and the still unqualified ones exit the production line.

[0016] Further, the volume of the fresh-keeping coating liquid is calculated by the following formula: Among them: is the volume of the fresh-keeping coating liquid required for a single egg; is the target fresh-keeping coating thickness; is the volume fraction of the film-forming substance in the coating liquid; The volume of the fresh-keeping coating liquid required for a single egg is determined, and the corresponding volume of the fresh-keeping coating liquid is applied by the immersion coating and spraying device according to the control, and then hot air drying is solidified.

[0017] Compared with the prior art, the beneficial effects of the present application are: pre-coating a sacrificial protective film before cleaning to avoid damage to the natural outer membrane during cleaning, the natural outer membrane is intact after removing the membrane, and the uniformity of coating is significantly improved; automatically identifying chicken eggs and duck eggs through the egg type identification index and calling corresponding parameters to realize integrated processing on the same line; the disinfection effect index realizes quantitative judgment and closed-loop control of disinfection to avoid insufficient or excessive disinfection; the comprehensive drying index realizes the judgment of the drying degree of each egg before coating, and the unqualified products are shunted for secondary drying and re-judgment to ensure the coating quality; a quantitative transfer chain from the pre-coating thickness, cleaning time, membrane removal condition to the coating liquid amount is established to realize accurate control of the whole process; uniform coating on the intact natural outer membrane effectively prolongs the shelf life of the eggs and improves the quality. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 It is a flowchart of the method for integrated cleaning and sterilization of chicken eggs and duck eggs. DETAILED DESCRIPTION

[0019] To make the purpose, technical scheme and advantages of the present application clearer, the present application is further described in detail below with specific examples.

[0020] It should be noted that the technical terms or scientific terms used in the present application should be the general meanings understood by those skilled in the art unless otherwise defined. The terms "first", "second" and the like used in the present application do not represent any order, number or importance, but are only used to distinguish different components. The terms "include" or "contain" and the like mean that the elements or objects before the terms cover the elements or objects listed after the terms and their equivalents, and do not exclude other elements or objects. The terms "connect" or "connected" and the like are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. The terms "upper", "lower", "left", "right" and the like are only used to represent relative positional relationships, and when the absolute positions of the described objects change, the relative positional relationships may also change accordingly.

[0021] Embodiments: Please refer to Figure 1 The present application provides the following technical solutions: A method for integrated cleaning, sterilization and preservation of chicken eggs and duck eggs, comprising: S1: collecting the initial weight, eggshell color reflectance, major axis and minor axis of the poultry eggs, wherein the initial weight is directly measured by an online weighing sensor, the eggshell color reflectance is directly measured by a color sensor, and the major axis and the minor axis are directly measured by a visual measurement device; the above parameters are substituted into a preset egg type discrimination index formula to calculate the egg type discrimination index of the poultry eggs.

[0022] The egg type discrimination index is calculated by the following formula: Wherein: K is the egg type discrimination index; W0 is the initial weight, unit g, directly measured by an online weighing sensor; Wref is the weight reference value, unit g, which is a preset constant, usually taking the overall average of the weights of chicken eggs and duck eggs; R is the eggshell color reflectance, directly measured by a color sensor, the higher the reflectance, the lighter the eggshell color; the lower the reflectance, the darker the eggshell color; Rref is the color reflectance reference value, a large number of known chicken egg and known duck egg samples are selected, the color reflectance of the eggshell of each sample is measured by a color sensor, and the statistical average or median of the reflectance of the two types of samples is taken as Rref; and stored in the control system for calling when calculating the egg type discrimination index in S1; the may be recalibrated according to different varieties or production line requirements; is the long diameter, i.e. the maximum dimension of the egg along its length direction; is the short diameter, i.e. the maximum dimension of the egg along its width direction; is the weight term, which is a normalized weight reflecting the degree of overweight or underweight of the egg product relative to a reference weight. Duck eggs are generally heavier than chicken eggs, so the weight term of a duck egg is generally greater than that of a chicken egg; is the color term, which is a normalized color reflectance; chicken egg shells have various colors, such as white, brown, and pink; duck egg shells are mostly white or green, and the overall reflectance distribution is different from that of chicken eggs. This term is used to capture the color characteristics; is the shape term, which reflects the elongation of the egg product. Duck eggs are generally more elongated than chicken eggs, so the shape term of a duck egg is generally greater than that of a chicken egg; , , are weight coefficients of the weight term, the color term, and the shape term, respectively, determined by experiments, and represent the contribution of the weight term, the color term, and the shape term to the discrimination result.

[0023] The calculated egg species discrimination index is compared with a preset threshold . The can be calibrated according to different varieties, production areas, or production lines and stored in the control system for real-time calling by S1. When , the bird egg is determined to be a duck egg and is given an egg species label ; when , the bird egg is determined to be a chicken egg and is given an egg species label .

[0024] The preset threshold is obtained by experimental calibration; a large number of known chicken egg and known duck egg samples are selected, the initial weight, egg shell color reflectance, long diameter, and short diameter of each sample are measured according to the method described in S1, and the egg species discrimination index of each sample is calculated; the value distribution of the two types of samples, i.e. chicken eggs and duck eggs, is counted, a distribution curve is drawn, and the demarcation point that minimizes the misjudgment rate of the two types of samples is selected as the . The can be calibrated according to different varieties, production areas, or production lines and stored in the control system for real-time calling by S1.

[0025] The egg shell surface area is calculated by the following formula: wherein: is the egg shell surface area; The egg shape coefficient is a dimensionless calibration constant used to correct the difference between the actual shape of the egg and the standard ellipsoid. During calibration, samples of eggs with known real surface area are selected, and their real surface area is measured using three-dimensional scanning or the standard ellipsoid method. The long diameter and the short diameter of each sample are measured, and the real surface area of each sample is divided by the product of the long diameter and the short diameter to obtain the egg shape coefficient of the sample. After removing outliers, the statistical average value is taken as the egg shape coefficient of the egg species. Chicken eggs and duck eggs can be calibrated separately, and the calibrated egg shape coefficient is stored in the control system for calling when calculating the eggshell surface area in S1. The egg shape coefficient is a dimensionless constant, which can be recalibrated for different varieties, production areas or production lines.

[0026] The egg is sent to the pre-coating station, and the pre-coating liquid is uniformly contacted with the eggshell surface by immersion or spraying. Then, the pre-coating liquid is dried by hot air to solidify the film-forming material in the pre-coating liquid on the eggshell surface to form a layer of water-soluble sacrificial protective film. The pre-coating liquid is preferably a sodium alginate-glycerol complex aqueous solution, in which sodium alginate is the main film-forming body, and glycerol is the plasticizer. Both are food-grade raw materials. The sacrificial protective film covers the outside of the natural eggshell membrane and acts as a physical barrier during subsequent cleaning and sterilization to prevent the natural eggshell membrane from being damaged by direct contact with water and disinfectant.

[0027] Before applying the sacrificial protective film, the egg is first subjected to dry pre-cleaning, which removes large particle dirt on the eggshell surface by dry brushing with a brush, air blowing or negative pressure adsorption. The pre-coating liquid contains a food-grade surfactant to wet, disperse and weaken the adhesion of small particles and microparticles to the eggshell surface. As a result, the eggshell surface is basically clean when the sacrificial protective film is pre-coated.

[0028] After pre-coating drying is completed, the film thickness is calculated by combining the pre-determined density of the sacrificial protective film and the calculated eggshell surface area.

[0029] The pre-coating film thickness is calculated by the following formula: Wherein: is the pre-coating film thickness; is the film layer mass after pre-coating drying, which is directly measured by the weight difference between the egg before and after pre-coating; is the density of the sacrificial protective film, which is directly measured by experiment.

[0030] S2: Calculate the cleaning time according to the pre-coating film thickness and the minimum allowed residual sacrificial protective film thickness, and the cleaning time calculation formula is: Wherein: This refers to the cleaning time; The minimum sacrificial protective film thickness, expressed in cm, is a preset value representing the minimum film thickness that must remain on the eggshell surface at the end of cleaning to ensure that the natural outer membrane is not exposed. Pre-coated eggs were used in a warm water cleaning experiment to determine the critical film thickness at which the natural outer membrane begins to be exposed during the gradual dissolution of the sacrificial protective film. This critical film thickness was taken as... ; The cleaning and erosion rate coefficient, measured in cm / (s·℃), is determined directly through experiments. Pre-coated eggs are sprayed and cleaned at a set water temperature, and the film thickness change is measured at different cleaning times. The film thickness reduction per unit time and per unit temperature is calculated and averaged. This coefficient is related to the film material, water temperature, and cleaning method, and is stored in the control system.

[0031] The temperature of the cleaning water is expressed in °C and is directly measured by a temperature sensor, indicating the real-time temperature of the water used for warm water spray cleaning.

[0032] After determining the cleaning time, the warm water spray device is used to clean the eggs accordingly. During cleaning, warm water spraying is combined with brushing, and microbubbles or ultrasound are introduced into the cleaning water. This causes the sacrificial protective membrane to gradually swell, soften, and erode. Dirt encased on the outer surface and inside the membrane is peeled off and washed away along with part of the membrane under the cavitation effects of the spray water, brushing, and microbubbles or ultrasound, while the eggshell surface retains the remaining sacrificial protective membrane, preventing the natural outer membrane from directly contacting water and disinfectant. If the cleaning time is too short, the dirt will not be completely removed; if it is too long, the remaining membrane thickness will be insufficient or even completely eroded, leading to exposure and damage to the natural outer membrane. Therefore, the cleaning time, as the cleaning control parameter of S2, directly determines the execution duration of the cleaning process and the remaining membrane thickness on the eggshell surface after cleaning.

[0033] The disinfection reference standard for the corresponding egg type is called according to the egg type label output by S1; the effective chlorine concentration, temperature and disinfection contact time of the disinfectant are measured in real time by the concentration sensor, temperature sensor and timer respectively, and the above measured values ​​are substituted into the preset disinfection effect index formula to calculate the disinfection effect index of the current disinfection process.

[0034] The disinfection effectiveness index is calculated using the following formula: in: The disinfection effectiveness index; This refers to the effective chlorine concentration of the disinfectant. The temperature of the disinfectant solution; This refers to the disinfection contact time; effective chlorine concentration reference value; disinfectant temperature reference value; disinfection contact time reference value.

[0035] effective chlorine concentration reference value The effective chlorine concentration reference value can be determined as follows: disinfection tests are respectively performed on chicken eggs and duck eggs, the disinfectant temperature and the contact time are fixed, the effective chlorine concentration is changed step by step, the minimum concentration value reaching the target sterilization rate is recorded, and then a safety margin is considered to serve as the effective chlorine concentration reference value of the egg species, which is stored in the control system for automatic calling by S2 and can be recalibrated according to the species or production line.

[0036] disinfectant temperature reference value The disinfectant temperature reference value is determined by reverse deduction through sterilization tests. The effective chlorine concentration and the contact time are kept unchanged, the disinfectant temperature is adjusted, and the minimum temperature making the sterilization rate reach the requirement is found out. The temperature is determined as the effective chlorine concentration reference value after adding a certain safety margin. The chicken eggs and duck eggs are calibrated respectively, and the results are written into the control system. S2 calls according to the egg species mark and corrects if necessary.

[0037] disinfection contact time reference value After the effective chlorine concentration and the temperature are fixed, the sterilization effect under different contact times can be determined, the time point just meeting the sterilization requirement is selected, and the safety margin is appropriately extended, so as to obtain the disinfection contact time reference value. The value is calibrated according to the egg species and stored for calling by S2 when calculating the disinfection effect index, and can also be adjusted according to the production line requirement.

[0038] The disinfection effect index is used to determine whether the disinfection effect of sodium hypochlorite hot water immersion sterilization meets the requirement. The control system obtains the real-time calculated disinfection effect index, compares the disinfection effect index with the preset qualified value, and determines that the current disinfection process meets the sterilization requirement and the disinfection is qualified when the disinfection effect index reaches the preset qualified value, so that the control system allows the batch of poultry eggs to enter S3 for membrane removal, dryness determination and shunting; When the disinfection effect index is lower than the preset qualified value, it is determined that the disinfection is unqualified, the control system sends an alarm signal, and at least one parameter of the effective chlorine concentration of the disinfectant, the disinfectant temperature and the disinfection contact time is automatically adjusted until the recalculated disinfection effect index reaches the preset qualified value, so that the poultry eggs can enter S3. Through the above determination and adjustment, online quantitative determination and closed-loop control of the disinfection process are realized, disinfection deficiency leading to microbial residue is avoided, and excessive disinfection causing energy waste and eggshell damage is also avoided, so as to ensure the hygiene conditions of the subsequent membrane removal, drying and coating processes.

[0039] ​S3: using warm water spray or weak acid solution soaking method, the remaining sacrificial protective film left on the eggshell surface after cleaning is gradually dissolved and removed. The weak acid solution is preferably a citric acid solution or an acetic acid solution. After the sacrificial protective film is dissolved, the natural outer membrane on the eggshell surface is exposed. Then, the air knife is used to dry, remove the residual moisture on the eggshell surface, and make the eggshell surface reach the initial state required for subsequent dryness determination.

[0040] After the film is dried, the weight of the poultry egg is directly measured by an online weighing sensor, which is recorded as the weight of the poultry egg after film drying; the humidity of the eggshell surface is directly measured by an infrared moisture sensor; and the temperature of the eggshell surface is directly measured by an infrared temperature sensor. The above three parameters together with the initial weight stored in S1 constitute the directly measured data required for comprehensive dryness index calculation.

[0041] The comprehensive dryness index calculation formula is: Wherein: is the comprehensive dryness index; is the initial weight; is the weight after film drying; is the humidity of the eggshell surface; is the surface humidity reference value; is the temperature of the eggshell surface; is the surface temperature reference value; is the weight loss rate, reflecting the degree of overall moisture loss of the poultry egg during film drying. The greater the weight loss rate, the more sufficient the moisture removal, and the higher the dryness; is the surface humidity deviation rate, reflecting the immediate dryness of the eggshell surface. The smaller the value is, the greater the value is, indicating that the eggshell surface is drier. Using the form can make the contribution of the surface humidity be greater when the surface humidity is lower; is the surface temperature ratio, reflecting the driving force of hot air drying. The higher the surface temperature, the more sufficient the hot air drying, but it needs to be controlled within a reasonable range to avoid affecting the quality of the egg; , , are the weight coefficients of the weight loss rate, the surface humidity deviation rate and the surface temperature ratio, respectively, determined by experiment calibration, representing the contribution of the weight loss rate term, the surface humidity term and the surface temperature term to the dryness determination The calculated comprehensive drying index is compared with the preset drying threshold value corresponding to the egg species. When the comprehensive drying index reaches or exceeds the preset drying threshold value corresponding to the egg species, it is determined that the poultry egg is dry and qualified, and the control system allows it to enter S4 along the main conveying path for preservative coating; when the comprehensive drying index is lower than the preset drying threshold value corresponding to the egg species, it is determined that the poultry egg is dry and unqualified, and the control system diverts it to the secondary drying channel through a pneumatic push rod or a rotary dial.

[0042] The preset drying threshold value is obtained by experimental calibration. A large number of known dry qualified chicken egg and duck egg samples are selected respectively, the poultry egg weight after membrane air drying, eggshell surface humidity and eggshell surface temperature are measured, and the comprehensive drying index of each sample is calculated combined with the initial weight; at the same time, the coating uniformity, coating adhesion and preservation effect of each sample are detected, and the critical value of the comprehensive drying index that can make the coating quality meet the standard and the dry qualified judgment error rate is the lowest is determined as the preset drying threshold value corresponding to the egg species. The preset drying threshold value is calibrated for chicken eggs and duck eggs respectively, and can be adjusted according to the variety, origin or production line requirements, and is stored in the control system after calibration, and the egg species mark output by S1 is automatically called.

[0043] For unqualified poultry eggs with a comprehensive drying index lower than the preset drying threshold value corresponding to the egg species, the control system diverts them to the secondary drying channel. At this time, the control system calculates the secondary drying time according to the current weight loss rate, target weight loss rate, egg species correlation coefficient, secondary drying hot air temperature and secondary drying air speed. Among them, the current weight loss rate is determined by the initial weight stored in S1 and the poultry egg weight after membrane air drying measured by S3, the target weight loss rate and the egg species correlation coefficient are automatically called by the egg species mark output by S1, and the secondary drying hot air temperature and the secondary drying air speed are measured in real time by the temperature sensor and the air speed sensor.

[0044] The secondary drying time is calculated by the following formula: Among them: is the time required for secondary drying is the egg species correlation coefficient, which is automatically called by the egg species mark output by S1 is a preset calibration constant for correcting the different drying rates of chicken eggs and duck eggs due to the differences in eggshell structure; known chicken egg and duck egg samples are selected respectively, and the drying time required for each sample to reach the target weight loss rate is determined under the same secondary drying hot air temperature and air speed conditions, and the ratio of the drying time required for duck eggs to the drying time required for chicken eggs is taken as the egg species correlation coefficient of duck eggs, and the egg species correlation coefficient of chicken eggs is taken as 1.

[0045] is the target weight loss rate, corresponding to the egg species Target loss rate of the target species, determined by S1 Automatically called, preset calibration value, indicating the total loss rate required for the egg species to meet the dry qualification requirements; Current loss rate, determined by the initial weight of the egg stored in S1 and the real-time measured weight of the egg after membrane drying in S3. Specifically, the initial weight directly measured in S1 is subtracted from the weight of the egg after membrane drying directly measured in S3 to obtain the weight loss of the egg during the membrane drying process. Then, the weight loss is divided by the initial weight, and the resulting ratio is the current loss rate; Secondary drying hot air temperature, unit: ℃, directly measured in real time by a temperature sensor; Secondary drying air speed, unit: m / s, directly measured in real time by an air speed sensor.

[0046] The secondary drying time is used to control the duration of hot air drying of the separated eggs in the secondary drying channel. The control system controls the hot air temperature, air speed, and running time in the secondary drying channel according to the calculated secondary drying time, so that the eggs complete the supplementary drying within the set time. After the secondary drying is completed, the eggs are re-evaluated for the comprehensive drying index, and the weight after membrane drying, the eggshell surface humidity, and the eggshell surface temperature are measured again, and the initial weight stored in S1 is used to recalculate the comprehensive drying index. The recalculated comprehensive drying index is compared again with the preset drying threshold value of the corresponding egg species. If the recalculated comprehensive drying index reaches or exceeds the preset drying threshold value of the corresponding egg species, it is determined that the egg is dry after secondary drying and is allowed to enter S4 for preservation coating. If it is still lower than the preset drying threshold value of the corresponding egg species, it is determined that the egg is still not qualified after secondary drying, and it is removed from the production line and does not enter the coating process. Through the above secondary drying and re-evaluation steps, S3 forms a closed loop control, avoids dry unqualified eggs entering the coating process, ensures the uniformity of the eggshell surface dryness before coating, improves the uniformity of the coating and the product qualification rate, and enables chicken eggs and duck eggs to be processed on the same production line.

[0047] S4: The control system calls the eggshell surface area calculated by S1, combines the preset target preservation coating thickness and the real-time measured volume fraction of the film-forming substance in the coating solution, and calculates the volume of the preservation coating solution required for a single egg. The volume of the preservation coating solution is calculated by the following formula: Wherein: Volume of the preservation coating solution required for a single egg; The target preservation coating thickness refers to the average thickness of the preservation coating layer expected to form on the surface of the poultry eggshell, measured in cm. This is a preset calibration value that can be adjusted according to the type of egg, coating material, and preservation requirements. Chicken and duck egg samples were selected separately, and preservation coatings of different thicknesses were applied to the eggshells with intact natural outer membranes. The coverage, uniformity, adhesion, and preservation effect of the coatings at each thickness were tested. The optimal coating thickness range was determined based on the criteria of uniform coating, satisfactory preservation effect, and no impact on eggshell permeability. It is usually set to 0.005 cm to 0.02 cm.

[0048] The volume fraction of the film-forming substance in the coating solution is determined by mixing the film-forming substance with the solvent according to a preset volume ratio during preparation. The ratio of the added film-forming substance volume to the total volume of the coating solution is then measured. Alternatively, it can be measured directly online using a concentration sensor, densitometer, or refractometer. During calibration, coating solutions with different volume fractions are prepared, and the coating thickness, uniformity, and preservation effect at each volume fraction are tested. The optimal range is determined based on the criteria of uniform coating, good adhesion, and satisfactory preservation.

[0049] Based on the determined volume of preservative coating liquid required per egg, the control system controls the dipping or spraying device to apply the corresponding volume of preservative coating liquid to each egg, ensuring the coating liquid is evenly spread on the eggshell surface with intact natural outer membrane. Since the natural outer membrane of the eggshell is retained after membrane removal, the surface condition is consistent, and chicken and duck eggs use the same process parameters, thus achieving consistent coating thickness and coverage for both types of eggs. The amount of coating liquid used is determined by the eggshell surface area, the target preservative coating thickness, and the volume fraction of film-forming substances in the coating liquid. The eggshell surface area is calculated from the major axis, minor axis, and egg shape coefficient in S1 and transferred to S4, ensuring precise matching of the coating liquid application amount to the actual surface area of ​​each egg, avoiding waste or insufficient coating thickness. After applying the coating liquid, hot air drying is used to solidify the coating liquid into a film, forming a uniform preservative coating layer that prevents microbial invasion and moisture loss, thereby extending the shelf life of the eggs and ensuring consistent preservative coating effects on the surfaces of chicken and duck eggs with intact natural outer membranes.

[0050] The above formulas are all dimensionless calculations. The formulas are derived from software simulations using a large amount of collected data, and are the closest to the real situation. The preset parameters in the formulas are set by those skilled in the art according to the actual situation.

[0051] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented in software, the above embodiments can be implemented, in whole or in part, as a computer program product. Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution.

[0052] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment, depending on actual needs.

[0053] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. A method for integrated cleaning, sterilization, and preservation of chicken and duck eggs, characterized in that, include: S1: Collect the initial weight, eggshell color reflectance, major axis and minor axis of the poultry eggs, calculate the egg species discrimination index, identify the poultry eggs as chicken eggs or duck eggs and assign egg species labels; The eggshell surface area is calculated based on the major diameter, minor diameter, and egg shape coefficient; a water-soluble sacrificial protective film is applied to the eggshell surface; the thickness of the pre-coated film is calculated based on the quality of the pre-coated film after drying, the density of the sacrificial protective film, and the eggshell surface area. S2: Calculate the cleaning time based on the pre-coated film thickness and the minimum allowable remaining sacrificial protective film thickness; automatically call the disinfection reference standard for the corresponding egg type based on the egg type marking, calculate the disinfection effect index based on the effective chlorine concentration of the disinfectant, the temperature of the disinfectant and the disinfection contact time, and determine whether the disinfection is qualified; use warm water spray cleaning, then soak in hot sodium hypochlorite water for sterilization, and blow dry with an air knife; S3: Dissolve and remove the sacrificial protective membrane to expose the natural outer membrane of the eggshell, and dry it with an air knife; measure the weight of the poultry egg after membrane removal and air drying, the surface humidity of the eggshell, and the surface temperature of the eggshell; calculate the comprehensive drying index based on the initial weight, the weight after membrane removal and air drying, the surface humidity of the eggshell, and the surface temperature of the eggshell, and compare it with the preset drying threshold of the corresponding egg type; if qualified, proceed to S4; if unqualified, it is diverted to the secondary drying channel. The secondary drying time is calculated based on the current weight loss rate, target weight loss rate, egg type correlation coefficient, secondary drying hot air temperature and secondary drying wind speed. Secondary drying is carried out, and the results are re-evaluated after secondary drying. If the results are qualified, the product enters S4; otherwise, it is removed from the production line. S4: Calculate the volume of preservative coating liquid required for a single poultry egg based on the eggshell surface area, the target preservative coating thickness, and the volume fraction of film-forming substances in the coating liquid. Apply the preservative coating to the eggshell surface with intact natural outer membrane and dry and cure it with hot air.

2. The integrated cleaning, sterilization, and preservation method for chicken and duck eggs according to claim 1, characterized in that: The egg species discrimination index is calculated using the following formula: Where: K is the egg species discrimination index; This is the initial weight; Weight reference value The reflectance of the eggshell color; This is a reference value for color reflectance; It is the major axis; It is the minor axis; For weight; For color items; For shape items; , , These are the weight coefficients for the weight, color, and shape items, respectively.

3. The integrated cleaning, sterilization, and preservation method for chicken and duck eggs according to claim 2, characterized in that: Egg species discrimination index With preset threshold Comparison; the preset threshold The critical value for the egg species discrimination index used to distinguish between chicken eggs and duck eggs is determined by measuring a large number of known chicken and duck eggs respectively. Values, statistically analyzing the two types of eggs. Value distribution, select the boundary point that minimizes the false positive rate as ;when The current egg is determined to be a duck egg and an egg species label is assigned. ,when The current egg is determined to be a chicken egg and an egg species label is assigned. .

4. The integrated cleaning, sterilization, and preservation method for chicken and duck eggs according to claim 1, characterized in that: The surface area of ​​the eggshell is calculated using the following formula: in: This represents the surface area of ​​the eggshell. The egg shape coefficient; The thickness of the pre-coated film is calculated using the following formula; in: This refers to the thickness of the pre-coated film. To determine the quality of the pre-coated film after drying; For sacrificial protective film density.

5. The integrated cleaning, sterilization, and preservation method for chicken and duck eggs according to claim 4, characterized in that: The formula for calculating the cleaning time is: in: This refers to the cleaning time; Minimum sacrificial protective film thickness; This is the cleaning and dissolution rate coefficient; For cleaning water temperature; The disinfection effectiveness index is calculated using the following formula: in: The disinfection effectiveness index; This refers to the effective chlorine concentration of the disinfectant. The temperature of the disinfectant solution; This refers to the disinfection contact time; This is the baseline value for available chlorine concentration; This is the baseline value for the temperature of the disinfectant solution; This is the baseline value for disinfection contact time.

6. The integrated cleaning, sterilization, and preservation method for chicken and duck eggs according to claim 5, characterized in that: The control system determines the cleaning time based on the output pre-coated film thickness and the preset minimum residual sacrificial protective film thickness after cleaning, and controls the spray device to clean the poultry eggs with warm water. During the cleaning process, the surface of the sacrificial protective film gradually dissolves and carries away dirt, and the eggshell surface still retains the residual sacrificial protective film at the end of the cleaning. The disinfection effect index is used to determine whether the disinfection effect of sodium hypochlorite hot water soaking in S2 meets the standard: the disinfection effect index is compared with the preset qualified value. When the disinfection effectiveness index reaches the preset qualified value, the disinfection is deemed qualified and poultry eggs are allowed to enter S3; When the disinfection effectiveness index is lower than the preset qualified value, the disinfection is deemed unqualified, the control system alarms and adjusts the disinfection parameters until it is qualified.

7. The integrated cleaning, sterilization, and preservation method for chicken and duck eggs according to claim 1, characterized in that: The formula for calculating the comprehensive dryness index is as follows: in: The comprehensive dryness index; This is the initial weight; This is the weight after the film has been removed and the product has been air-dried. The humidity of the eggshell surface; This is a reference value for surface humidity. The surface temperature of the eggshell; This is a reference value for surface temperature. The rate of weightlessness; Surface humidity deviation rate; The surface temperature ratio; , , These are the weighting coefficients for weight loss rate, surface humidity deviation rate, and surface temperature ratio, respectively.

8. The integrated cleaning, sterilization, and preservation method for chicken and duck eggs according to claim 1, characterized in that: The secondary drying time is calculated using the following formula: in: This refers to the time required for secondary drying; The correlation coefficient between egg species; The target weightlessness rate; This represents the current rate of weightlessness. This refers to the temperature of the secondary drying hot air. This is the secondary drying air velocity.

9. The integrated cleaning, sterilization, and preservation method for chicken and duck eggs according to claim 8, characterized in that: The comprehensive drying index is used in S3 to determine the dryness of each egg after de-filming and air drying; the control system compares the calculated comprehensive drying index with the preset drying threshold of the corresponding egg type, and when the preset drying threshold is reached, it is determined that the drying is qualified and allowed to enter S4 coating. When the overall drying index is lower than the preset drying threshold, the eggs are deemed unqualified and diversion is triggered, directing them into the secondary drying channel. The secondary drying time is used to control the duration of hot air drying of poultry eggs in the secondary drying channel after diversion. After the secondary drying is completed, the comprehensive drying index of poultry eggs is re-evaluated. Those that pass the evaluation enter S4, and those that still fail the evaluation are removed from the production line.

10. The integrated cleaning, sterilization, and preservation method for chicken and duck eggs according to claim 2, characterized in that: The volume of the preservative coating liquid is calculated using the following formula: in: This represents the volume of preservative coating liquid required for a single poultry egg; The target preservation coating thickness; This represents the volume fraction of the film-forming substance in the coating solution. Determine the required volume of preservative coating liquid for a single poultry egg, and control the application of the corresponding volume of preservative coating liquid using the dipping and spraying devices accordingly, followed by hot air drying and curing.

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