Fresh-keeping processing method of green bamboo shoots

Abstract

The invention relates to the technical field of food processing, and discloses a green bamboo shoot fresh-keeping processing method which comprises the following steps: S1, pretreating green bamboo shoot raw materials; s2, on the basis of the pretreated green bamboo shoots, constructing an endogenous gel network to obtain green bamboo shoots containing the gel network; s3, collecting quality characteristic parameters of the green bamboo shoots containing the gel network, and optimizing the hot processing technology based on a preset mathematical model so as to obtain a customized hot processing technology; and S4, performing hot processing treatment on the green bamboo shoots containing the gel network by applying the customized hot processing technology so as to obtain a green bamboo shoot product which can be preserved at normal temperature. An endogenous gel network with a mechanical supporting effect is constructed in situ in the internal tissues of the green bamboo shoots, and the problems of excessive tissue softening and structure collapse caused by high temperature and high pressure in the traditional heat sterilization process are effectively solved by combining the optimization of a heat processing technology taking the maximization of the texture retention rate as an optimization target.

Description

Technical Field

[0001] The invention relates to the technical field of food processing, in particular to a green bamboo shoot preservation processing method. Background Art

[0002] Green bamboo shoots, a beloved food ingredient, are renowned for their uniquely tender, crisp texture. However, their intense postharvest respiration makes them susceptible to fibrosis and deterioration, resulting in a very short shelf life. This severely restricts their commercial distribution and industrial development. Therefore, effective preservation processing of green bamboo shoots to extend their supply period and maintain their excellent quality is of great market value and practical significance.

[0003] Currently, heat sterilization is the primary and most reliable method for industrial production to achieve long-term storage and transportation of green bamboo shoots and other fruits and vegetables at room temperature. High-temperature and high-pressure treatment effectively kills any spoilage microorganisms and pathogens that may be present in the product, ensuring its commercial sterility and food safety.

[0004] However, existing heat sterilization technology faces an inherent contradiction that is difficult to reconcile when applied to texture-sensitive products such as green bamboo shoots. In order to achieve the necessary sterilization intensity, the high temperature and long-term heat treatment applied will inevitably cause serious and irreversible damage to the fragile plant tissue structure of green bamboo shoots. Heat will cause the degradation and depolymerization of key structural components such as pectin and cellulose in the cell wall, loosening the connections between cells, causing the green bamboo shoots to lose their most valuable crisp taste. The texture of the final product becomes overly soft and rotten, which is far from the sensory experience of fresh raw materials, greatly reducing the product's acceptance and added value.

[0005] Furthermore, the currently commonly used heat processing techniques typically rely on a set of fixed, empirical process parameters. This model does not fully account for the natural variability of green bamboo shoots as biological raw materials, such as differences in size, tenderness, and moisture content between different harvest batches and individuals. To ensure that products meet safety standards in all situations, these fixed process parameters are often designed based on worst-case scenarios. For most raw materials, this means undergoing far more excessive processing than necessary. This widespread over-heat treatment further exacerbates the unnecessary loss of product texture, flavor, and nutrients, leading to a bottleneck in optimizing and improving product quality.

[0006] At the same time, if the endogenous enzymes naturally present in the green bamboo shoots raw materials, such as polyphenol oxidase, are not effectively inhibited in the early stages of processing, they will also cause browning of the product color and the production of unpleasant flavors during subsequent processing and storage, further affecting the overall quality of the product.

[0007] Therefore, how to protect the original crisp and tender texture of green bamboo shoots to the greatest extent while ensuring the microbial safety of the product, and to carry out precise and intelligent processing control based on the characteristics of the raw materials, is a technical problem that needs to be urgently solved in the current field of green bamboo shoot preservation and processing. Summary of the Invention

[0008] In view of the shortcomings of the existing technology, the present invention provides a green bamboo shoot preservation processing method, which solves the inherent contradiction that the traditional green bamboo shoot heat sterilization process will inevitably seriously damage its unique crisp taste while achieving commercial sterility to ensure food safety.

[0009] To achieve the above objectives, the present invention is implemented through the following technical solutions: A green bamboo shoot preservation processing method comprises the following steps: S1, pre-treating green bamboo shoots raw materials; S2. constructing an endogenous gel network based on the pretreated green bamboo shoots to obtain green bamboo shoots containing a gel network; S3. collecting quality characteristic parameters of green bamboo shoots containing a gel network, and optimizing the thermal processing process based on a preset mathematical model to obtain a customized thermal processing process; S4. Apply the customized thermal processing technology to perform thermal processing on the green bamboo shoots containing the gel network to obtain a green bamboo shoot product that can be kept fresh at room temperature.

[0010] Preferably, in step S1, the pretreatment operation includes performing enzyme inactivation treatment on the green bamboo shoots to inhibit their endogenous enzyme activity.

[0011] Preferably, in step S2, the endogenous gel network construction includes: allowing a solution containing a biopolymer precursor to penetrate into the internal tissue of the pretreated green bamboo shoots, and forming a gel network with mechanical support in situ in the internal tissue through ionic crosslinking.

[0012] Preferably, in the construction of the endogenous gel network, the step of allowing the solution containing the biopolymer precursor to penetrate into the internal tissue of the pretreated green bamboo shoots specifically includes: infiltrating the solution containing the biopolymer precursor into the internal tissue of the pretreated green bamboo shoots by vacuum infiltration.

[0013] Preferably, in the construction of the endogenous gel network, the biopolymer precursor comprises alginate and pectin; and the ionic crosslinking is achieved by calcium ions.

[0014] Preferably, in step S3, the preset mathematical model includes: A quality degradation kinetics model that characterizes the degree of product quality degradation during thermal processing; A microbial inactivation model that characterizes the degree of inactivation of microorganisms during thermal processing.

[0015] Preferably, in step S3, the step of optimizing the heat treatment process is specifically as follows: taking maximizing the product texture retention rate and minimizing the processing time as the optimization goal, and solving the process parameters of the customized heat treatment process under the constraint of meeting the preset sterilization safety standards.

[0016] Preferably, the preset mathematical model further includes: a gel network degradation kinetics model that characterizes the change in integrity of the gel network during thermal processing, and maximizing the gel network integrity is used as the optimization goal of optimizing the thermal processing process.

[0017] Preferably, in step S3, the specific steps of collecting the quality characteristic parameters of the green bamboo shoots containing the gel network are: obtaining the physical or chemical characteristic parameters of the green bamboo shoots with the gel network through online monitoring, and using the parameters to dynamically calibrate the preset mathematical model.

[0018] Preferably, the online monitoring method is near infrared spectroscopy or acoustic sensing detection.

[0019] The present invention provides a green bamboo shoot preservation processing method, which has the following beneficial effects: 1. The present invention effectively solves the problems of excessive tissue softening and structural collapse caused by high temperature and high pressure in the traditional heat sterilization process by in situ constructing an endogenous gel network with mechanical support in the internal tissue of green bamboo shoots, and combining it with thermal processing technology optimization with maximizing texture retention as the optimization goal. The gel network provides additional physical support for plant cells, so that the final product can retain the unique crisp and tender taste of green bamboo shoots to the maximum extent, thereby improving the sensory quality and market competitiveness of the product.

[0020] 2. The present invention introduces online monitoring methods to collect raw material quality parameters in real time, and uses these parameters to dynamically calibrate a composite mathematical model that includes quality deterioration, microbial inactivation, and gel network degradation. This achieves personalized customization of the thermal processing technology for each batch of products, breaking away from the limitation of traditional fixed process parameters that cannot adapt to differences between raw material batches, and ensuring the accuracy of the processing process and the high stability and consistency of the final product quality.

[0021] 3. The present invention takes minimizing processing time as one of the optimization goals and performs multi-objective solving under the strict constraint of ensuring that the sterilization value meets the commercial sterility safety standards. It can effectively protect product quality while finding the optimal process path required to achieve the sterilization goal, avoiding excessive sterilization often caused by traditional processes to ensure safety, thereby better protecting heat-sensitive nutrients and flavor substances, saving energy consumption, and improving overall production efficiency.

[0022] 4. The present invention not only focuses on the changes in the quality of green bamboo shoots themselves, but also incorporates the changes in the integrity of the constructed gel network itself into the mathematical model and optimization goals. By actively seeking to inhibit the degradation of the gel network during the optimization process, it achieves dual synergistic protection of the physical support structure and the supported biological tissue, ensuring that the internal reinforcement structure remains effective after thermal processing, thereby guaranteeing the texture quality of the final product.

[0023] 5. The present invention uses online nondestructive testing technologies such as near-infrared spectroscopy or acoustic sensing, combined with automated data processing and process optimization decision-making systems, to construct a complete intelligent processing flow with closed-loop control. This method has high automation potential and good operability, can effectively cope with the natural fluctuations in raw material quality in industrial production, and can easily achieve standardized and large-scale production applications. It provides a new technical approach for the deep processing of high-quality fruit and vegetable products and has broad industrial prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a flow chart of the method of the present invention; Figure 2 Schematic diagram of the process of step S2 of the present invention; Figure 3 Schematic diagram of the process of step S3 of the present invention; Figure 4 Schematic diagram of the feedback mechanism of the present invention. DETAILED DESCRIPTION

[0025] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0026] Please see the attached Figure 1 -Attached Figure 4 The present invention provides a green bamboo shoot preservation processing method, comprising the following steps: S1. Pre-treating green bamboo shoots raw materials.

[0027] Regarding step S1, in this embodiment, step S1 is to pretreat the green bamboo shoots raw material. This step is intended to provide starting materials with stable quality and uniform state for the subsequent refined processing flow, and is the basis and prerequisite for ensuring the quality consistency of the final product of the method of the present invention.

[0028] First, the green bamboo shoots used in the processing method of the present invention are selected. To ensure the quality of the final product, fresh green bamboo shoots with uniform size, intact shape, fresh texture, no rot, no pests and diseases, and no severe mechanical damage are preferably selected.

[0029] Next, the selected green bamboo shoots are cleaned. In a specific embodiment, the surface of the green bamboo shoots can be fully rinsed with running water to completely remove dirt, sand and other impurities that may be attached to the surface, thereby ensuring the hygienic safety of the processing process.

[0030] The cleaned green bamboo shoots are then shaped and cut. This involves removing the rough, hard outer shell and removing the more fibrous root. The processed bamboo shoots are then cut into blocks, slices, or strips of relatively uniform size and thickness, depending on the desired shape of the final product. This standardized cutting process ensures that subsequent steps, such as heat transfer and material penetration, are consistent across each unit of material.

[0031] In order to further ensure the final quality of the product, this step S1 preferably includes performing enzyme inactivation treatment on the green bamboo shoots, which is an important technical feature of the pretreatment link of the present invention.

[0032] Specifically, green bamboo shoots naturally contain a variety of endogenous enzymes, such as polyphenol oxidase (PPO) and peroxidase (POD). If the activity of these enzymes is not effectively inhibited during processing and subsequent storage, they will catalyze the oxidation of polyphenols, causing undesirable browning of the product and potentially leading to flavor degradation, seriously affecting the product's sensory quality and commercial value.

[0033] Therefore, in an embodiment of the present invention, the enzyme activity inactivation treatment can be achieved by briefly blanching the cut green bamboo shoots in hot water. Preferably, the blanching temperature can be controlled within the range of 95-100°C, and the treatment time is adaptively adjusted according to the size and thickness of the bamboo shoots. This heat treatment can irreversibly change the spatial structure of the above-mentioned endogenous enzymes, thereby quickly and completely inactivating their activity.

[0034] In addition to achieving the aforementioned enzyme inactivation goal, the blanching treatment also moderately softens the cell walls and tissue structure of the bamboo shoots through brief periods of high temperature, potentially making the intercellular layer between cells more porous and significantly improving the permeability of the tissue. This creates extremely favorable physical conditions for the subsequent biopolymer precursor solution to quickly, efficiently, and evenly penetrate deep into the bamboo shoot's internal tissue, thereby ensuring the uniformity and effectiveness of the endogenous gel network construction.

[0035] After the above pretreatment steps, pretreated green bamboo shoots with stable state, inhibited enzyme activity and suitable for penetration are obtained, which lays a solid foundation for the smooth implementation of subsequent steps.

[0036] S2. Based on the pretreated green bamboo shoots, an endogenous gel network is constructed to obtain green bamboo shoots containing a gel network.

[0037] Regarding step S2, in this embodiment, step S2 is based on the pretreated green bamboo shoots obtained in step S1, and an endogenous gel network is constructed to obtain green bamboo shoots containing a gel network. This step is the core technological innovation of the present method at the material science level. Its fundamental purpose is not to form a passive coating on the surface of the bamboo shoots, but to actively transform a single plant tissue into a biopolymer composite material with stronger thermomechanical stability through microstructural reshaping, laying a physical foundation for solving the problem of texture deterioration during subsequent high-temperature sterilization.

[0038] Step S2 consists of two closely connected and sequential stages: first, the infiltration stage of the biopolymer precursor solution, followed by the in-situ curing stage of ionic cross-linking.

[0039] About the solution penetration stage The core task of this stage is to efficiently and evenly transport the biopolymer precursors deep into the internal tissue of the pretreated green bamboo shoots. Specifically, it is necessary to first prepare an aqueous solution containing biopolymer precursors. The biopolymer precursors preferably contain alginate and pectin. The reason for selecting these substances is that they are all naturally derived, safe and edible hydrophilic colloids, and their molecular chains contain a large number of functional groups that can undergo cross-linking reactions with metal cations, making them ideal substrates for the gel network of the present invention.

[0040] To achieve efficient penetration, the present invention preferably uses vacuum penetration to perform this stage. Specifically, the pretreated green bamboo shoots that have completed step S1 and have been sufficiently cooled can be completely immersed in the prepared biopolymer precursor solution, and the solid-liquid mixture is placed in a sealed and vacuum-evacuated container. The vacuum equipment is activated to reduce the pressure in the container to a negative pressure state and maintain it for a period of time.

[0041] The principle of this operation is that the negative pressure environment will cause the gas retained in the microscopic pores and intercellular spaces inside the bamboo shoot tissue to escape due to the pressure difference. Subsequently, when the vacuum is quickly broken and the container is restored to normal pressure, the pressure of the external environment will be much greater than the residual pressure inside the tissue. This huge pressure difference will become a powerful driving force, rapidly and deeply pressing the external biopolymer precursor solution into the internal space of the tissue from which the gas has been expelled. Compared with traditional atmospheric pressure immersion, vacuum penetration can significantly improve the depth and uniformity of penetration, ensuring that the subsequent gel network can be widely formed throughout the bamboo shoot tissue, rather than just staying on the surface.

[0042] About the ionic crosslinking in-situ curing stage The core task of this stage is to assemble the successfully delivered biopolymer precursors into a three-dimensional solid network through chemical reactions, providing practical mechanical support. The key to this process is in situ formation, meaning that the network construction occurs within the internal tissue environment of the bamboo shoot.

[0043] The specific operation is to take out the green bamboo shoots that have passed the vacuum infiltration stage from the biopolymer precursor solution, drain off the excess solution attached to the surface of the green bamboo shoots, and then immediately immerse them in the pre-prepared ionic crosslinking agent solution.

[0044] The ionic crosslinking is preferably achieved by calcium ions. Therefore, the ionic crosslinking agent solution is preferably a food-grade salt solution containing divalent calcium ions, such as calcium chloride solution or calcium lactate solution.

[0045] When bamboo shoots are immersed in this calcium salt solution, the smaller, more mobile calcium ions naturally diffuse into the shoot tissue due to the concentration gradient. When these calcium ions encounter previously infiltrated macromolecules of alginate or pectin within the tissue, a cross-linking reaction occurs. The mechanism is that a single divalent calcium ion simultaneously electrostatically bonds with two negatively charged functional groups on two different or the same polymer chains, locking and connecting the previously independent, freely moving long polymer chains.

[0046] This cross-linking process occurs continuously at the microscopic level, ultimately transforming the originally dissolved and dispersed biopolymer precursor into a continuous, water-insoluble, three-dimensional network with a certain degree of elasticity and mechanical strength—the gel network constructed in this invention. Because this network is constructed entirely within the tissue pores of the bamboo shoot itself, it interweaves and interpenetrates with natural structures such as the plant cell wall, forming a synergistic composite support system.

[0047] After completing the above two stages, the green bamboo shoots containing the gel network are prepared. This product retains the original shape of the bamboo shoots on a macroscopic level, but its internal structure has been effectively enhanced and reinforced by the edible-grade gel network on a microscopic level. The presence of this gel network provides effective physical support to resist the deterioration of cell walls and tissue structure caused by high temperature and high pressure during subsequent thermal processing, which is the key to the invention's ability to achieve the purpose of preserving freshness and crispness.

[0048] S3. Collect the quality characteristic parameters of the green bamboo shoots containing the gel network, and optimize the thermal processing technology based on a preset mathematical model to obtain a customized thermal processing technology.

[0049] Regarding step S3, in this embodiment, step S3 is to collect the quality characteristic parameters of the green bamboo shoots containing the gel network and optimize the thermal processing process based on a preset mathematical model to obtain a customized thermal processing process. This step is what distinguishes the method of the present invention from the traditional sterilization process with fixed parameters. Its core lies in transforming the static and empirical processing method into a dynamic and intelligent decision-making process based on scientific calculations. Step S3 consists of the following two steps: About the collection of quality characteristic parameters and dynamic calibration of models This step is the fundamental guarantee for the accuracy of subsequent optimization decisions. Since the green bamboo shoots containing the gel network obtained after step S2 may still have slight batch-to-batch variations in key properties such as the degree of internal gel network formation, moisture distribution, and initial texture, the present invention introduces a dynamic parameter acquisition and calibration mechanism to eliminate the impact of these variations on the quality of the final product.

[0050] The present invention preferably uses online monitoring to accomplish this task. In a specific embodiment, the green bamboo shoots containing the gel network produced in step S2 can be passed through an online detection unit, which is preferably integrated with a non-invasive sensor, such as a near-infrared spectroscopy sensor or an acoustic sensing detection device.

[0051] As green bamboo shoots pass through, sensors can quickly acquire their physical or chemical signatures. For example, near-infrared spectrometers can analyze diffuse reflectance spectroscopy data to correlate the sample's various chemical components and physical structure. Acoustic sensors can assess the sample's mechanical properties by analyzing its response to specific sound waves.

[0052] The collected raw sensor signals are analyzed using a pre-established calibration model and converted in real time into a series of quality characteristic parameters for subsequent optimization calculations. These parameters not only characterize the initial state but, more importantly, serve as the basis for dynamic calibration of the pre-set mathematical model in this step. Specifically, these measured values ​​are used to modify or update key constants in the mathematical model in real time, ensuring that the model accurately reflects the actual physical and chemical state of the batch being processed.

[0053] On process optimization and decision-making based on mathematical models This link is the core calculation process of this step, and its goal is to find an optimal balance point between multiple mutually constrained quality and efficiency indicators.

[0054] The preset mathematical model is a coupled, multi-dimensional model system, which preferably includes the following parts: Transient heat transfer model: used to predict how heat is transferred from the external medium to the interior of the package and ultimately to the geometric center of the product during thermal processing. This model is expressed by Fourier's law of heat conduction: ; in, is temperature; For time; is the density; is the specific heat capacity; is the thermal conductivity.

[0055] The above-mentioned thermophysical parameters are obtained or corrected through the aforementioned online monitoring and dynamic calibration links, ensuring the accuracy of heat transfer calculations.

[0056] Microbial inactivation model: used to quantitatively evaluate the degree of killing of target heat-resistant microorganisms under a certain temperature-time course. The present invention adopts a general F-value model: ; in, is the sterilization value; For product cold spots at time The instantaneous temperature; is the reference temperature; is the microbial heat resistance constant.

[0057] During the optimization process, the calculated The value must meet the minimum standard required by the regulation, which is a hard constraint.

[0058] The quality degradation kinetic model is used to describe the decay of key texture indicators representing the crispness of green bamboo shoots during heat treatment. This process generally follows first-order kinetics, and the temperature dependence of its rate constant can be described by the Arrhenius equation: ; in, is the pre-exponential factor; is the activation energy of the texture deterioration reaction; is the ideal gas constant; It is the maximum breaking force measured by the instrument.

[0059] Gel network degradation kinetic model: used to describe the degradation of the integrity of the endogenous gel network constructed in step S2 during heat treatment. Its model structure is similar to the quality deterioration model: ; in, For gel network integrity ( ) over time( ) changes, i.e., the degradation rate of the gel network; Gel network integrity, used to quantify the gel network structure at any time Indicators of integrity; For time; It is the pre-exponential factor or frequency factor of the gel network degradation reaction, which is a reaction rate constant; The base of natural logarithms; is the activation energy of the gel network degradation reaction, which represents the minimum energy required to initiate the degradation reaction; is the ideal gas constant; is the absolute temperature.

[0060] After the above model is established and dynamically calibrated, the system starts the process of optimizing the thermal processing process. This is a multi-objective collaborative optimization problem, and its mathematical form can be expressed as: ; ; in, is the decision variable vector representing the adjustable process parameters, such as heating rate, constant temperature, constant temperature time, etc.; 、 and There are three objective functions that need to be optimized.

[0061] In order to use process parameters The maximum breaking force of the final green bamboo shoot product after processing is a key indicator for quantitatively characterizing the final texture (brittleness) of the product; In order to use process parameters The final integrity index of the gel network inside the green bamboo shoots after processing, which is used to measure the degree to which the internal support structure remains intact; To adopt process parameters The total time required to complete the entire thermal processing process; is the constraint function of the optimization problem, used to ensure food safety; According to the process parameters The calculated cumulative kill value, which quantifies the effectiveness of the thermal process in killing microorganisms; The minimum target sterilization value required by regulations or process standards is the safety bottom line that must be met to ensure that the product reaches commercial sterility.

[0062] This optimization problem is solved by a multi-objective evolutionary algorithm. The result is not a single optimal solution, but a set called the Pareto optimal solution set, where each solution represents a different trade-off strategy between different objectives.

[0063] Ultimately, the system automatically selects the optimal set of process parameters from this solution set based on pre-set production preferences. This parameter combination fully encompasses the variable temperature-time profiles for the ramp-up, hold-temperature, and ramp-down phases, representing a customized thermal process. This process is then passed on to subsequent steps to guide precise thermal processing.

[0064] S4. Apply the customized thermal processing technology to perform thermal processing on the green bamboo shoots containing the gel network to obtain a green bamboo shoot product that can be kept fresh at room temperature.

[0065] In this embodiment, step S4 involves applying the customized thermal processing technique obtained in step S3 to the green bamboo shoots containing the gel network obtained in step S2 to obtain a green bamboo shoot product that can be kept fresh at room temperature. This step is the final physical execution link of the entire method flow of the present invention. Its core task is to transform the results of all intellectual decisions and physical transformations in the previous steps into a high-quality finished product through precise thermodynamic process control.

[0066] Specifically, the implementation of this step first involves preparatory work before heat processing of the green bamboo shoots containing the gel network. The green bamboo shoots containing the gel network, which have been processed in step S2 and monitored online in step S3, are loaded into a packaging container suitable for subsequent high-temperature and high-pressure processing according to preset quantitative specifications. The packaging container can be a flexible material retort bag with good thermal conductivity and barrier properties, or a hard container such as a glass bottle. After loading, a small amount of seasoning liquid can be injected into the container according to the needs of the product flavor design, and the packaging container is then vacuum-sealed. This vacuum sealing operation not only helps to eliminate oxygen in the package to extend the shelf life, but more importantly, it ensures that the package contents are tightly fitted to the container wall, thereby creating conditions for efficient and uniform heat transfer during subsequent heat processing.

[0067] Next, we enter the stage of applying the customized thermal processing technology to perform precise thermal processing. The implementation of this stage relies on a thermal processing equipment that can perform precise program control, such as a programmable sterilizer or autoclave. The core feature of this equipment is that its control system can receive and execute complex, nonlinear temperature and time instructions.

[0068] In this embodiment of the present invention, the customized thermal processing process output by the optimization calculation module in step S3 is an ideal temperature-time curve tailored to the current batch of products, including multiple stages of heating, maintaining a constant temperature, and cooling, with accuracy down to the second. This curve instruction is transmitted and loaded into the control system of the thermal processing equipment.

[0069] After the equipment is started, its control system will monitor the actual temperature inside the equipment and the product cold spot monitored by the probe in real time, and through a closed-loop feedback control logic, it will accurately regulate the flow, temperature and pressure of the heating medium and cooling medium, so that the actual temperature change curve of the product cold spot can track and reproduce the preset target temperature curve to the greatest extent.

[0070] It is worth noting that precise execution is crucial here. The reason why the complex mathematical model and optimization algorithm in step S3 are meaningful is that the premise is the high precision of the physical execution level. The traditional fixed parameter sterilization method has a simple process curve and does not require high equipment. The customized process curve generated by the present invention may be a complex curve containing multiple temperature rising sections with different slopes, multiple short-time constant temperature platforms and precisely controlled temperature falling sections. Only through this high-precision execution can we ensure that during the entire thermal processing process, a lethal dose sufficient to kill the target microorganisms can be accumulated, and the total loss of product quality and the integrity of the internal gel network under thermal load can be controlled to the minimum level determined by the optimization algorithm.

[0071] After the heating and constant-temperature sterilization phases, this customized process also guides an optimized, rapid, and uniform cooling process. By precisely controlling the spraying or circulation of cooling water, the product is quickly cooled to room temperature. This rapid cooling process promptly terminates the thermal effects, preventing the product from experiencing additional quality deterioration due to prolonged exposure to high temperatures, and thus solidifying the freshness and crispness preservation achieved during the heating phase.

[0072] Finally, after the complete heat treatment in step S4 and cooling, a green bamboo shoot fresh-keeping processed product is obtained that can be stored and sold at room temperature for a long time while retaining its crisp and tender texture to the maximum extent. At this point, the technical process of the entire invention method is closed-loop.

[0073] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A method for preserving green bamboo shoots, characterized in that: The following steps are involved: S1, pre-treating green bamboo shoots raw materials; S2. constructing an endogenous gel network based on the pretreated green bamboo shoots to obtain green bamboo shoots containing a gel network; S3. collecting quality characteristic parameters of green bamboo shoots containing a gel network, and optimizing the thermal processing process based on a preset mathematical model to obtain a customized thermal processing process; S4. Apply the customized thermal processing technology to perform thermal processing on the green bamboo shoots containing the gel network to obtain a green bamboo shoot product that can be kept fresh at room temperature.

2. A green bamboo shoot preservation processing method according to claim 1, characterized in that, In step S1, the pretreatment operation includes performing enzyme inactivation treatment on the green bamboo shoots to inhibit the endogenous enzyme activity.

3. A green bamboo shoot preservation processing method according to claim 1, characterized in that, In step S2, the endogenous gel network construction includes: allowing a solution containing a biopolymer precursor to penetrate into the internal tissue of the pretreated green bamboo shoots, and forming a gel network with a mechanical support function in situ in the internal tissue through ionic crosslinking.

4. A green bamboo shoot preservation processing method according to claim 3, characterized in that, In the construction of the endogenous gel network, the step of allowing the solution containing the biopolymer precursor to penetrate into the internal tissue of the pretreated green bamboo shoots specifically includes: infiltrating the solution containing the biopolymer precursor into the internal tissue of the pretreated green bamboo shoots by vacuum infiltration.

5. A green bamboo shoot preservation processing method according to claim 3, characterized in that: In the construction of the endogenous gel network, the biopolymer precursor comprises alginate and pectin; and the ionic cross-linking is achieved through calcium ions.

6. A method for preserving green bamboo shoots according to claim 1, characterized in that: In step S3, the preset mathematical model includes: A quality degradation kinetics model that characterizes the degree of product quality degradation during thermal processing; A microbial inactivation model that characterizes the degree of inactivation of microorganisms during thermal processing.

7. A method for preserving green bamboo shoots according to claim 1, characterized in that: In step S3, the step of optimizing the heat treatment process is specifically as follows: taking maximizing the product texture retention rate and minimizing the processing time as the optimization goals, and under the constraint of meeting the preset sterilization safety standards, solving and obtaining the process parameters of the customized heat treatment process.

8. The method for preserving green bamboo shoots according to claim 1, wherein: In step S3, the preset mathematical model further includes: a gel network degradation kinetics model that characterizes the change in integrity of the gel network during the thermal processing, and maximizing the gel network integrity is used as the optimization goal of optimizing the thermal processing process.

9. A method for preserving green bamboo shoots according to claim 1, characterized in that: In step S3, the specific steps of collecting the quality characteristic parameters of the green bamboo shoots containing the gel network are: obtaining the physical or chemical characteristic parameters of the green bamboo shoots with the gel network through online monitoring, and using the parameters to dynamically calibrate the preset mathematical model.

10. A method for preserving green bamboo shoots according to claim 9, characterized in that: The online monitoring method is near infrared spectroscopy or acoustic sensing detection.

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