Method for obtaining the actual shelf life of a product based on the packaging and the environment in which it is located

Abstract

The application discloses a method for obtaining actual shelf life of a product based on packaging and environment, and comprises the following steps: obtaining information of a storage environment where the product is located; obtaining an internal target humidity range of the product packaging; obtaining an equivalent exchange coefficient based on quantification of the airtightness of the product packaging; obtaining a humidity adjusting material setting scheme of the product packaging, and obtaining an equivalent humidity adjusting coefficient according to the humidity adjusting material setting scheme; constructing a fitting dynamic prediction model and coupling inputting the storage environment information, the internal target humidity range, the equivalent humidity adjusting coefficient and the equivalent exchange coefficient to obtain a breaking limit time when the internal humidity of the product packaging exceeds the target humidity range; and obtaining the actual shelf life of the product according to the breaking limit time. The actual shelf life of the product can be predicted according to the storage environment of the product and the humidity adjusting material setting scheme, namely the final packaging scheme of the product.

Description

Technical Field

[0001] This invention relates to the field of product packaging technology, and in particular to a method for obtaining the actual shelf life of a product based on its packaging and surrounding environment. Background Technology

[0002] As the coverage of modern distribution networks continues to expand and the scale of cross-regional commodity trade grows rapidly, the quality assurance requirements for different product categories in the storage and transportation process are constantly upgrading. Among these, humidity control is one of the core indicators for ensuring the quality of most perishable and easily damaged products. Currently, the industry's commonly used product packaging humidity control solutions generally adopt a standardized packaging structure combined with a fixed ratio of humidity-regulating materials, using a generic design logic. This mainly relies on the product's conventional long-term storage parameters and the characteristics of common distribution environments to pre-determine the type, quantity, and packaging method of humidity-regulating materials. It does not specifically adapt to the differentiated storage and transportation needs of different orders. In fact, there are no relevant data standards for the specific shelf life of various packaging methods, or if there are empirical standards, they cannot be dynamically adjusted in real time according to the packaging conditions.

[0003] In summary, the industry currently lacks methods that can be optimized for short-term storage and transportation scenarios and that can determine the actual shelf life of products based on actual storage environment parameters and actual packaging design. The adaptability and economy of existing packaging technologies cannot meet the development needs of the current refined circulation of goods, and corresponding technical solutions are urgently needed to fill the industry gap. Summary of the Invention

[0004] In view of the above-mentioned shortcomings of current product packaging technology, the present invention provides a method for obtaining the actual shelf life of a product based on the packaging and its environment, which can predict the actual shelf life of the product based on the product's storage environment and humidity control material settings, i.e., the final packaging scheme of the product.

[0005] To achieve the above objectives, the embodiments of the present invention adopt the following technical solutions:

[0006] A method for obtaining the actual shelf life of a product based on its packaging and surrounding environment, the method comprising the following steps:

[0007] Obtain information about the storage environment where the product is located;

[0008] Obtain the target humidity range inside the product packaging;

[0009] Obtain the equivalent exchange coefficient based on the airtightness quantification of product packaging;

[0010] Obtain the humidity conditioning material setting scheme for the product packaging, and obtain the equivalent humidity conditioning coefficient based on the humidity conditioning material setting scheme;

[0011] A fitting dynamic prediction model is constructed and the stored environmental information, internal target humidity range, equivalent humidity regulation coefficient, and equivalent exchange coefficient are coupled as inputs to obtain the time when the humidity inside the product packaging exceeds the target humidity range.

[0012] The actual shelf life of the product is obtained based on the time of the failure.

[0013] According to one aspect of the present invention, the storage environment information includes at least: information on changes in the external temperature and external humidity of the product during storage.

[0014] According to one aspect of the invention, the equivalent exchange coefficient is defined as the equivalent number of air changes or a time constant.

[0015] According to one aspect of the present invention, the target humidity range in the acquisition of the target humidity range inside the product packaging is expressed as water vapor partial pressure or humidity ratio.

[0016] According to one aspect of the invention, the equivalent humidity control coefficient is obtained based on the combined effects of packaging material moisture permeability, effective area, arrangement, and gas phase mixing.

[0017] According to one aspect of the invention, the upper limit of the predicted shelf life of the actual product is less than or equal to 90 days.

[0018] According to one aspect of the present invention, obtaining a humidity-regulating material setting scheme for product packaging and obtaining an equivalent humidity-regulating coefficient based on the humidity-regulating material setting scheme includes: having a preset reference library of humidity-regulating material setting schemes and equivalent humidity-regulating coefficients, and obtaining the equivalent humidity-regulating coefficient based on the reference library after obtaining the humidity-regulating material setting scheme.

[0019] According to one aspect of the present invention, the fitted dynamic prediction model is:

[0020] de_in / dt = k_e(T_bar, a_bar) · (e_out - e_in) - K_m(T_in, a_in) · (e_in - e_set)

[0021] Where, a_in = RH_in / 100, a_out = RH_out / 100, T_bar = (T_in + T_out) / 2, a_bar = (a_in + a_out) / 2, e_in = a_in·e_s(T_in), e_out = a_out·e_s(T_out), e_set(T_in) = a_w·e_s(T_in); T_in is the internal temperature of the product packaging, T_out is the external ambient temperature of the product packaging; e_s(T_out) is the external temperature T_ saturated vapor pressure at temperature T_in; e_s(T_in) is the saturated vapor pressure at internal temperature T_in; e_set(T_in) is the set partial pressure of the material at internal temperature T_in at time t; a_w is the water activity of the material; a_in is the water activity inside the product packaging; a_out is the water activity of the external environment of the product packaging; K_m is the equivalent humidity control coefficient; k_e is the equivalent exchange coefficient; de_in / dt is the rate of change of the partial pressure of water vapor inside the product packaging with time t; RH_in is the relative humidity inside the product packaging; RH_out is the relative humidity outside the product packaging.

[0022] According to one aspect of the invention, the selection of the humidity-regulating material should satisfy the following conditions: the material is in a reversible moisture absorption and release operating range within the predicted upper limit of the actual product shelf life, and is not close to the capacity limit.

[0023] According to one aspect of the invention, the packaging structure or sealing condition of the product packaging remains stable within the predicted upper limit of the actual product shelf life.

[0024] The advantages of this invention are: it allows for the determination of a product's actual shelf life based on its packaging, facilitating precise shelf-life labeling, optimizing warehousing and logistics strategies, and providing a scientific basis for quality control and risk warning. Furthermore, this method avoids the uncertainties introduced by traditional accelerated aging tests, improving the reliability and practicality of shelf-life prediction, and is particularly suitable for assessing the stability of temperature- and humidity-sensitive products in complex distribution environments. By combining the moisture-regulating properties and sealing characteristics of packaging materials with dynamic parameters of the external environment, the fitted dynamic prediction model constructed in this invention can reflect the changing trends of the product's internal microenvironment in real time, thereby achieving high-precision dynamic correction of the shelf-life within the upper limit of the prediction. Detailed Implementation

[0025] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] Example 1

[0027] A method for obtaining the actual shelf life of a product based on its packaging and surrounding environment, the method comprising the following steps:

[0028] Step S1: Obtain information about the storage environment where the product is located;

[0029] The storage environment information includes at least: information on changes in the external temperature and humidity of the product during storage.

[0030] Specifically, based on the actual production, transportation, storage, and sales time and location of the product, the external temperature and humidity change curves experienced by the product are obtained, covering diurnal temperature differences during transportation, seasonal fluctuations in the storage environment, and sudden climate disturbances. This can be achieved by deploying environmental monitoring nodes or accessing historical meteorological databases to obtain temperature and humidity time-series data for at least seven consecutive days. The data sampling frequency can be selected to be no less than once per hour. After standardization, the data is coupled with the product's moisture adsorption isotherm to quantify the dynamic driving intensity of external water vapor disturbances on the microenvironment inside the packaging. For example, if the product is produced in Shanghai and is expected to be sold in Hangzhou, hourly temperature and humidity data measured by meteorological stations along the Shanghai-Hangzhou route over the past 30 days are obtained to form temperature and humidity change curves.

[0031] In practical applications, in order to obtain relevant environmental information, historical environmental information can be used to predict the storage environment information within the subsequent storage period.

[0032] Step S2: Obtain the target humidity range inside the product packaging;

[0033] Based on the actual properties of the product and its storage environment requirements, the target humidity range that needs to be maintained inside the product packaging is obtained. Specifically, in practical applications, the target humidity range inside the product packaging is expressed as water vapor partial pressure or humidity ratio. This embodiment uses water vapor partial pressure as an example for explanation. Let e_in = a_in·e_s(T_in), that is, at time t, e_in(t) = a_in(t)·e_s(T_in), where e_in(t) is the water vapor partial pressure inside the product packaging at time t, a_in is the water activity inside the product packaging, T_in is the temperature inside the product packaging, and e_s(T_in) is the saturated water vapor pressure at temperature T_in inside the product packaging. Therefore, in the actual product packaging process, the water activity range for product storage inside the packaging is usually agreed upon. For example, the water activity requirement for biscuit and cookie products is 0.2-0.4, and the water activity requirement for cake products is greater than 0.8.

[0034] In practical applications, the allowable fluctuation range [e_min, e_max] of the water vapor partial pressure e_in inside the product packaging can be determined based on the product's water activity safety threshold and shelf-life kinetic model. For example, for instant oatmeal with a water content of 45%, its water activity safety threshold is a≤0.65, corresponding to a saturated water vapor pressure e_s=3.169kPa at 25℃, so e_max=0.65×3.169≈2.06kPa; e_min is set based on the critical point for preventing dehydration, such as setting it to the minimum water vapor partial pressure of 0.8kPa required to prevent textural hardening, so [e_min, e_max]=[0.8,2.06]kPa; this range drifts dynamically with temperature, and e_s(T) needs to be calibrated across the entire temperature range and mapped to the corresponding a limit value.

[0035] Step S3: Obtain the equivalent exchange coefficient based on the airtightness quantification of the product packaging;

[0036] Obtain the product's current packaging form, such as boxed or bagged packaging, and calibrate its equivalent exchange coefficient k_e based on its structural characteristics and sealing process through standard leak rate testing or accelerated damp heat cycling testing; for example, for sealed boxes with adhesive strips, the k_e value is typically 0.8–1.2h. -1 The snap-fit ​​enclosure is 1.5–2.3h. -1 The sealing tape corresponds to k_e≈0.3–0.6h. -1 For valve-type structures, the k_e values ​​need to be calibrated in different open and closed states. A mapping relationship between k_e and structural parameters (such as seal line length, contact surface roughness, and adhesive layer thickness) needs to be established to provide a traceable engineering basis for subsequent parameter coupling. In practical applications, the equivalent exchange coefficient is defined as the equivalent air exchange rate or time constant.

[0037] Step S4: Obtain the humidity conditioning material setting scheme for the product packaging, and obtain the equivalent humidity conditioning coefficient based on the humidity conditioning material setting scheme;

[0038] The equivalent humidity control coefficient is obtained based on the combined effects of packaging material moisture permeability, effective area, layout, and gas phase mixing.

[0039] In practical applications, while keeping the material structure and packaging method unchanged, K_m can be approximately positively correlated with the effective moisture permeability area A of the material and the amount of material applied M, and inversely correlated with the volume V of the product packaging.

[0040] K_m≈α·(M / V) or K_m≈β·(A / V)

[0041] α and β are calculated from the calibration test over a period of about one week and are the equivalent strength coefficients corresponding to the unit amount of material applied. When the moisture permeability or geometric area of ​​the covering material is changed, that is, when the effective moisture permeability area A is changed, K_m will change accordingly.

[0042] Therefore, for any new effective permeable area A', product packaging volume V', and material dosage M', it can be predicted that: K_m'=α·(M' / V'), or K_m'≈β·(A' / V'), and combined with the already calibrated k_e (or the new k_e'), a 5-10 day prediction and a_w inverse solution can be performed.

[0043] The process of obtaining the humidity-regulating material setting scheme for the product packaging and obtaining the equivalent humidity-regulating coefficient based on the humidity-regulating material setting scheme includes: pre-setting a reference library of humidity-regulating material setting schemes and equivalent humidity-regulating coefficients; obtaining the humidity-regulating material setting scheme and then obtaining the equivalent humidity-regulating coefficient based on the reference library. This reference library is constructed based on dual verification using historical calibration data and physical modeling, covering different material types (silicone, montmorillonite, lithium chloride-based, etc.), unit volume dosage (g / L), inner surface area of ​​the packaging material (m²), temperature range adaptability (5℃–40℃), and response delay characteristics of the product packaging interior.

[0044] The selection of the humidity-regulating material should meet the following requirements: the material is in a reversible moisture absorption and release range within the predicted upper limit of the actual product shelf life, and is not close to the capacity limit.

[0045] Step S5: Construct a fitted dynamic prediction model and couple the saved environmental information, internal target humidity range, equivalent humidity regulation coefficient, and equivalent exchange coefficient into the input to obtain the time when the humidity inside the product packaging exceeds the target humidity range.

[0046] The fitted dynamic prediction model is as follows:

[0047] de_in / dt = k_e(T_bar, a_bar) · (e_out - e_in) - K_m(T_in, a_in) · (e_in - e_set)

[0048] Where, a_in = RH_in / 100, a_out = RH_out / 100, T_bar = (T_in + T_out) / 2, a_bar = (a_in + a_out) / 2, e_in = a_in·e_s(T_in), e_out = a_out·e_s(T_out), e_set(T_in) = a_w·e_s(T_in); T_in is the internal temperature of the product packaging, T_out is the external ambient temperature of the product packaging; e_s(T_out) is the external temperature T_ saturated vapor pressure at temperature T_in; e_s(T_in) is the saturated vapor pressure at internal temperature T_in; e_set(T_in) is the set partial pressure of the material at internal temperature T_in at time t; a_w is the water activity of the material; a_in is the water activity inside the product packaging; a_out is the water activity of the external environment of the product packaging; K_m is the equivalent humidity control coefficient; k_e is the equivalent exchange coefficient; de_in / dt is the rate of change of the partial pressure of water vapor inside the product packaging with time t; RH_in is the relative humidity inside the product packaging; RH_out is the relative humidity outside the product packaging.

[0049] The specific method for constructing the dynamic prediction model is as follows:

[0050] First, assuming a fixed product packaging volume V, the effect of changes in the total air volume inside the packaging on the partial pressure of water vapor is negligible; airtightness is represented by an equivalent exchange coefficient (including the combined effects of permeation, micro-leakage, and breathing effect); the humidity-regulating material can be considered as a "buffer" that pulls the partial pressure inside the product packaging back to its set partial pressure e_set, and the equivalent humidity-regulating intensity is represented by the coefficient K_m; the product packaging and material performance do not undergo irreversible degradation in the short term (approximately one week); if degradation occurs, a retest and correction can be performed in the second week. The selection of the humidity-regulating material should meet the following requirements: the material is in a reversible moisture absorption and release operating range within the target shelf life, and does not approach its capacity limit within the shelf life.

[0051] When the external environment can be considered approximately stable within a 5–10 day window (or replaced by a window average), the steady-state partial pressure of equation (1) is:

[0052] e*=(k_e·e_out+K_m·e_set) / (k_e+K_m) Formula (2)

[0053] If the product packaging is required to maintain a target humidity range (RH_tar, e.g., 62%RH), the target partial pressure can be obtained first:

[0054] e_tar=RH_tar·e_s(T_in) Formula (3)

[0055] The required partial pressure of the material is obtained by inverse solution of equation (2):

[0056] e_set=e_tar+(k_e / K_m)·(e_tar-e_out) Formula (4)

[0057] Then calculate the water activity of the material:

[0058] a_w=e_set / e_s(T_in) Equation (5)

[0059] The more humid the outside environment (the larger e_out), the lower a_w is required; the less airtight the enclosure (the larger k_e), the stronger the material is required (a larger K_m, or a lower a_w).

[0060] The equivalent humidity control coefficient K_m is obtained based on the combined effects of packaging material moisture permeability, effective area, layout, and gas phase mixing.

[0061] Step S6: Obtain the actual shelf life of the product based on the time of the expiration.

[0062] The predicted upper limit for the actual product shelf life is less than or equal to 90 days.

[0063] Within the predicted upper limit of the actual product shelf life, the packaging structure or sealing condition of the product packaging remains stable.

[0064] The specific forecasting workflow is as follows:

[0065] enter:

[0066] External conditions: T_out(t), RH_out(t) (or window statistics provided for 5–10 days);

[0067] Target: RH_tar (e.g., 62%) and allowable fluctuation range ±ΔRH;

[0068] Time window: 5–10 days;

[0069] Parameters: k_e (box airtightness, i.e., equivalent exchange coefficient, from control group calibration), K_m (material equivalent humidity regulation coefficient, from experimental group calibration), material dosage M, and product packaging volume V. k_e is obtained from Blank calibration; K_m or α / β is obtained from candidate material calibration.

[0070] step:

[0071] 1) Calculate the partial pressure of water vapor outside the product packaging at time t, e_out(t) = RH_out·e_s(T_out), and the representative value of the internal temperature of the product packaging, T_in (which can be the time average of Test or the critical operating point).

[0072] 2) The material strength, i.e. the equivalent moisture regulation coefficient K_m, is calculated using K_m=α(M / V);

[0073] 3) The water activity a_w of the candidate material is obtained by using the steady-state inverse solution (Equation 4–5);

[0074] 4) Use the dynamic model (Equation 1) to perform a 5-10 day simulation. Input the partial pressure of water vapor inside the product packaging e_out(t) and the temperature inside the product packaging T_in(t) at time t. Check whether the relative humidity RH_in(t) inside the product packaging at time t falls within the target range to determine whether the requirements are met. Alternatively, the simulation prediction can be used to determine whether the requirements are met based on the judgment criteria.

[0075] 5) If not satisfied: the time when the condition is not met shall be taken as the time of failure, and the time period from the product start time to the time of failure shall be taken as the reference value of the actual shelf life of the product. The actual shelf life of the product shall be less than or equal to the reference value.

[0076] In practical applications, when the constructed fitting dynamic prediction model is used to perform fitting dynamic simulation prediction to obtain the equivalent humidity control coefficient, the judgment criteria for whether the simulation prediction meets the requirements are designed and formulated according to the actual product. This embodiment is only an example. For example, the judgment criteria shown in Table 1 below can be used to determine whether the requirements are met:

[0077] Table 1:

[0078] Time-achieved rate Time-in-band ≥ 95% (or customer-defined) Calculate the percentage of time RH_in(t) is within the target window. Maximum deviation Max deviation ≤ upper limit of target deviation The maximum deviation exceeding 60±5%RH must not exceed 3%RH. Longest consecutive boundary crossings Longest excursion ≤ Specified number of hours To prevent short-term spikes from being masked by average values. Equilibrium time t_equilibrium ≤ Customer-allowed time If the standard is met too late within a one-week window, the actual protection time will be insufficient. Condensation risk T_surface - T_dewpoint ≥ safety margin It is recommended to use a surface / air paired sensor for determination. capacity margin Cumulative net moisture absorption / desorption ≤ 70–80% of effective capacity Short-term models should also avoid approaching material depletion.

[0079] In practical applications, different product judgment indicators can be set according to different product types, as shown in Table 2 below:

[0080] Table 2:

[0081] Probiotics Moisture content, a_w, short-term CFU changes, or early log loss under accelerated stress. Identify early risks to viable bacterial counts from excessive moisture or dryness. Moisture-sensitive tablets Appearance, color, hardness, tendency to disintegrate, and rapid increase in moisture. Identify signs of short-term dampness, clumping, discoloration, or abnormal physical properties. enzyme products Residual enzyme activity, a_w, moisture content, and appearance. Compare the short-term effects of unidirectional drying and bidirectional buffering. Diagnostic kits / LFA C / T line intensity, pass / fail, false positive / false negative risk signals. Determine whether weekly humidity exposure in logistics affects the stability of readings.

[0082] Example 2

[0083] A method for obtaining the actual shelf life of a product based on its packaging and surrounding environment, the method comprising the following steps:

[0084] Step S1: Obtain information about the storage environment where the product is located;

[0085] The storage environment information includes at least: information on changes in the external temperature and humidity of the product during storage.

[0086] Specifically, based on the actual production, transportation, storage, and sales time and location of the product, the external temperature and humidity change curves experienced by the product are obtained, covering diurnal temperature differences during transportation, seasonal fluctuations in the storage environment, and sudden climate disturbances. This can be achieved by deploying environmental monitoring nodes or accessing historical meteorological databases to obtain temperature and humidity time-series data for at least seven consecutive days. The data sampling frequency can be selected to be no less than once per hour. After standardization, the data is coupled with the product's moisture adsorption isotherm to quantify the dynamic driving intensity of external water vapor disturbances on the microenvironment inside the packaging. For example, if the product is produced in Shanghai and is expected to be sold in Hangzhou, hourly temperature and humidity data measured by meteorological stations along the Shanghai-Hangzhou route over the past 30 days are obtained to form temperature and humidity change curves.

[0087] In practical applications, in order to obtain relevant environmental information, historical environmental information can be used to predict the storage environment information within the subsequent storage period.

[0088] Step S2: Obtain the target humidity range inside the product packaging;

[0089] Based on the actual properties of the product and its storage environment requirements, the target humidity range that needs to be maintained inside the product packaging is obtained. Specifically, in practical applications, the target humidity range inside the product packaging is expressed as water vapor partial pressure or humidity ratio. This embodiment uses water vapor partial pressure as an example for explanation. Let e_in = a_in·e_s(T_in), that is, at time t, e_in(t) = a_in(t)·e_s(T_in), where e_in(t) is the water vapor partial pressure inside the product packaging at time t, a_in is the water activity inside the product packaging, T_in is the temperature inside the product packaging, and e_s(T_in) is the saturated water vapor pressure at temperature T_in inside the product packaging. Therefore, in the actual product packaging process, the water activity range for product storage inside the packaging is usually agreed upon. For example, the water activity requirement for biscuit and cookie products is 0.2-0.4, and the water activity requirement for cake products is greater than 0.8.

[0090] In practical applications, the allowable fluctuation range of the water vapor partial pressure e_in inside the product packaging can be determined based on the product's water activity (a) safety threshold and shelf-life kinetic model. min ,e max For example, for instant oatmeal with a moisture content of 45%, its safe threshold for water activity is a≤0.65, corresponding to a saturated water vapor pressure at 25℃ e_s=3.169kPa, from which we can obtain e max =0.65×3.169≈2.06kPa; e min The setting is based on the critical point for preventing dehydration. For example, if it is set to the minimum water vapor partial pressure required to prevent textural hardening, such as 0.8 kPa, then [e] min ,emax = [0.8, 2.06] kPa; This range drifts dynamically with temperature, and e_s(T) needs to be calibrated across the entire temperature range and mapped to the corresponding a limit.

[0091] Step S3: Obtain the equivalent exchange coefficient based on the airtightness quantification of the product packaging;

[0092] Obtain the product's current packaging form, such as boxed or bagged packaging, and calibrate its equivalent exchange coefficient k_e based on its structural characteristics and sealing process through standard leak rate testing or accelerated damp heat cycling testing; for example, for sealed boxes with adhesive strips, the k_e value is typically 0.8–1.2h. -1 The snap-fit ​​enclosure is 1.5–2.3h. -1 The sealing tape corresponds to k_e≈0.3–0.6h. -1 For valve-type structures, the k_e values ​​need to be calibrated in different open and closed states. A mapping relationship between k_e and structural parameters (such as seal line length, contact surface roughness, and adhesive layer thickness) needs to be established to provide a traceable engineering basis for subsequent parameter coupling. In practical applications, the equivalent exchange coefficient is defined as the equivalent air exchange rate or time constant.

[0093] Step S4: Obtain the humidity conditioning material setting scheme for the product packaging, and obtain the equivalent humidity conditioning coefficient based on the humidity conditioning material setting scheme;

[0094] The equivalent humidity control coefficient is obtained based on the combined effects of packaging material moisture permeability, effective area, layout, and gas phase mixing.

[0095] In practical applications, while keeping the material structure and coating method unchanged, K_m can be approximately positively correlated with the effective moisture permeability area A and the dosage M of the material, and inversely correlated with the head space volume V:

[0096] K_m ≈ α·(M / V) or K_m ≈ β·(A / V)

[0097] α and β are calculated from the calibration test over a period of about one week and are the equivalent strength coefficients corresponding to the unit amount of material applied. When the moisture permeability or geometric area A of the covering material is changed, K_m will change accordingly.

[0098] When A is reached, K_m will change accordingly.

[0099] Therefore, for any new effective permeable area A', product packaging volume V', and material dosage M', it can be predicted that: K_m'=α·(M' / V'), or K_m'≈β·(A' / V'), and combined with the already calibrated k_e (or the new k_e'), a 5-10 day prediction and a_w inverse solution can be performed.

[0100] The selection of the humidity-regulating material should meet the following requirements: the material is in a reversible moisture absorption and release range within the predicted upper limit of the actual product shelf life, and is not close to the capacity limit.

[0101] Step S5: Construct a fitted dynamic prediction model and couple the saved environmental information, internal target humidity range, equivalent humidity regulation coefficient, and equivalent exchange coefficient into the input to obtain the time when the humidity inside the product packaging exceeds the target humidity range.

[0102] The fitted dynamic prediction model is as follows:

[0103] de_in / dt = k_e(T_bar, a_bar) · (e_out - e_in) - K_m(T_in, a_in) · (e_in - e_set)

[0104] Where, a_in = RH_in / 100, a_out = RH_out / 100, T_bar = (T_in + T_out) / 2, a_bar = (a_in + a_out) / 2, e_in = a_in·e_s(T_in), e_out = a_out·e_s(T_out), e_set(T_in) = a_w·e_s(T_in); e_in(t) is the partial pressure of water vapor inside the product packaging at time t; e_out(t) is the partial pressure of water vapor outside the product packaging at time t; T represents temperature, T_in is the internal temperature of the product packaging, T_out is the external ambient temperature of the product packaging; e_s(T) is the saturated water vapor pressure at temperature T, and e_s(T_out) is the saturated water vapor pressure at external temperature T_out. Saturated vapor pressure, e_s(T_in) is the saturated vapor pressure at the internal temperature T_in; e_set(t) is the set partial pressure of the material at time t, which is determined by the material a_w and the internal temperature T_in of the product packaging, i.e., e_set(t) = a_w·e_s(T_in(t)), e_set(T_in) is the set partial pressure of the material at the internal temperature T_in at time t; a_w is the water activity of the material, a_in is the water activity inside the product packaging, and a_out is the water activity of the external environment of the product packaging; K_m is the equivalent humidity regulation coefficient; k_e is the equivalent exchange coefficient; de_in / dt is the rate of change of the partial pressure of water vapor inside the product packaging with time t; RH is the relative humidity, RH_in is the relative humidity inside the product packaging, and RH_out is the relative humidity outside the product packaging.

[0105] The specific method for constructing the dynamic prediction model is as follows:

[0106] First, assuming a fixed product packaging volume V, the effect of changes in the total air volume inside the packaging on the partial pressure of water vapor is negligible; airtightness is represented by an equivalent exchange coefficient (including the combined effects of permeation, micro-leakage, and breathing effect); the humidity-regulating material can be considered as a "buffer" that pulls the partial pressure inside the product packaging back to its set partial pressure e_set, and the equivalent humidity-regulating intensity is represented by the coefficient K_m; the product packaging and material performance do not undergo irreversible degradation in the short term (approximately one week); if degradation occurs, a retest and correction can be performed in the second week. The selection of the humidity-regulating material should meet the following requirements: the material is in a reversible moisture absorption and release operating range within the target shelf life, and does not approach its capacity limit within the shelf life.

[0107] When the external environment can be considered approximately stable within a 5–10 day window (or replaced by a window average), the steady-state partial pressure of equation (1) is:

[0108] e*=(k_e·e_out+K_m·e_set) / (k_e+K_m) Formula (2)

[0109] If the product packaging is required to maintain a target humidity range (RH_tar, e.g., 62%RH), the target partial pressure can be obtained first:

[0110] e_tar=RH_tar·e_s(T_in) Formula (3)

[0111] The required partial pressure of the material is obtained by inverse solution of equation (2):

[0112] e_set=e_tar+(k_e / K_m)·(e_tar-e_out) Formula (4)

[0113] Then calculate the water activity of the material:

[0114] a_w=e_set / e_s(T_in) Equation (5)

[0115] The more humid the outside environment (the larger e_out), the lower a_w is required; the less airtight the enclosure (the larger k_e), the stronger the material is required (a larger K_m, or a lower a_w).

[0116] The equivalent humidity control coefficient K_m is obtained based on the combined effects of packaging material moisture permeability, effective area, layout, and gas phase mixing.

[0117] Step S6: Obtain the actual shelf life of the product based on the time of the expiration.

[0118] In practical applications, the upper limit of the predicted shelf life of the actual product is less than or equal to 90 days.

[0119] In practical applications, the packaging structure or sealing condition of the product packaging remains stable within the predicted upper limit of the actual product shelf life.

[0120] The total weight W(t) of the product packaging is collected in real time by a weighing sensor, and W(t) is aligned with the internal temperature and humidity of the product packaging, as well as the external temperature and humidity of the product packaging, at the same timestamp or on a uniformly mapped time axis.

[0121] Calculated based on the total packaging weight W_test(t) of the experimental group and the total packaging weight W_blank(t) of the blank control group:

[0122] Δ_net(t) = [W_test(t) - W_test(0)] - [W_blank(t) - W_blank(0)], and calculate J_net(t) = dΔW_net(t) / dt to obtain the real-time moisture mass flux of the packaging system. Where W_Test(t) is the total weight of the test package containing the sample and / or conditioning material, W_blank(t) is the total weight of the blank control package, and J_net(t) is the net moisture mass flux after deducting blank drift.

[0123] The cumulative moisture load q(t) or cumulative moisture absorption load q_abs(t) is obtained by integrating J_net(t), and the capacity consumption rate of the humidity conditioning material is determined by q(t) / C_effective or q_abs(t) / C_effective, where C_effective is the effective working capacity of the humidity conditioning material within the product's allowable humidity range.

[0124] When J_net(t) and e_out(t)-e_in(t) change synchronously in time, it can be used to enhance the identification of the equivalent exchange coefficient k_e on the packaging side; when RH_in(t) remains stable while ΔW_net(t) continues to increase, it indicates that external moisture is entering the packaging and being absorbed by the humidity conditioning material or product, and the capacity consumption rate of the humidity conditioning material can be further calculated.

[0125] For a 7-day short-term verification window, q_7d=∫_0^7d J_net(t)dt or q_abs,7d=∫_0^7d max[J_net(t),0]dt can be calculated, and q_7d / C_effective or q_abs,7d / C_effective can be used as the effective capacity consumption rate of the material.

[0126] Wherein, C_effective is the effective moisture absorption or release capacity of the humidity-regulating material within the product's allowable humidity window, rather than the material's fully saturated capacity; when the capacity consumption rate exceeds the preset threshold, even if RH_in(t) is still within the target range, it should be determined that the packaging scheme has a risk of insufficient capacity margin.

[0127] The remaining capacity C_rema_ining(t) = C_effective - q_abs(t) is obtained based on the capacity consumption rate, and the capacity failure time t_capacity_fail is determined when the remaining capacity is lower than the preset threshold, the equivalent humidity coefficient K_m decays, or the humidity inside the product packaging rebounds.

[0128] The time when the internal humidity of the packaging exceeds the target humidity range (t_RH_fail) is compared with the capacity failure time (t_capacity_fail), and the actual shelf life or storage and transportation risk warning of the product is obtained based on the earlier occurrence time.

[0129] In practical applications, the specific process of this embodiment is as follows:

[0130] enter:

[0131] External conditions: T_out(t), RH_out(t) (or window statistics provided for 5–10 days);

[0132] Target: RH_tar (e.g., 62%) and allowable fluctuation range ±ΔRH;

[0133] Time window: 5–10 days;

[0134] Parameters: k_e (box airtightness, also known as equivalent exchange coefficient, from control group calibration), K_m (material equivalent humidity regulation coefficient, from experimental group calibration), material dosage M, and product packaging volume V.

[0135] step:

[0136] 1) Calculate the partial pressure of water vapor outside the product packaging at time t, e_out(t) = RH_out·e_s(T_out), and the representative value of the internal temperature of the product packaging, T_in (which can be the time average of Test or the critical operating point).

[0137] 2) The material strength, i.e. the equivalent moisture regulation coefficient K_m, is calculated using K_m=α(M / V);

[0138] 3) The water activity a_w of the candidate material is obtained by using the steady-state inverse solution (Equation 4–5);

[0139] 4) Use the dynamic model (Equation 1) to perform a 5-10 day simulation. Input the partial pressure of water vapor inside the product packaging e_out(t) and the temperature inside the product packaging T_in(t) at time t. Check whether the relative humidity RH_in(t) inside the product packaging at time t falls within the target range, or judge whether the simulation prediction meets the requirements based on the judgment criteria.

[0140] Alternatively, calculate the cumulative moisture load q(t) = ∫J_net(t)dt or the cumulative moisture absorption load q_abs(t) = ∫max[J_net(t),0]dt within the target shelf life based on the real-time quality flux, and obtain the capacity consumption rate q(t) / C_effective or q_abs(t) / C_effective by combining it with the effective working capacity C_effective of the humidity conditioning material; obtain the remaining capacity C_rema_ining(t) = C_effective - q_abs(t) based on the capacity consumption rate, and determine the capacity failure time t_capacity_fail when C_rema_ining(t) is lower than the preset threshold or the equivalent humidity conditioning coefficient K_m decays; compare the time t_RH_fail when the humidity inside the product packaging exceeds the target humidity range with the capacity failure time t_capacity_fail, and take the earlier of the two times as the risk failure time of the packaging and storage plan;

[0141] 5) If not satisfied: the time when the condition is not met shall be taken as the time of failure, and the time period from the product start time to the time of failure shall be taken as the reference value of the actual shelf life of the product. The actual shelf life of the product shall be less than or equal to the reference value.

[0142] 6) Prioritize adjusting the water activity of the material a_w; or further adjust the amount of material added M (improved through K_m), or improve the airtightness (reducing k_e).

[0143] In this embodiment, the failure time under different packaging scheme changes can be simulated and predicted multiple times through steps 4), 5), and 6), that is, a_w, K_m, and k_e are adjusted respectively to generate different packaging schemes. Then, the actual shelf life of different packaging schemes is given based on the simulation prediction results.

[0144] In practical applications, the judgment criteria for determining whether simulation prediction meets the requirements are designed and formulated based on the actual product. This embodiment is only an example. For instance, the judgment criteria shown in Table 1 of Embodiment 1 can be used to determine whether the requirements are met.

[0145] In practical applications, different product judgment indicators can be set according to different product types, as shown in Table 2 of Example 1.

[0146] Example 3

[0147] A method for proposing product packaging solutions based on the product's target shelf life, the method comprising the following steps:

[0148] A method for obtaining the actual shelf life of a product based on its packaging and surrounding environment, the method comprising the following steps:

[0149] Step S1: Obtain information about the storage environment where the product is located;

[0150] The storage environment information includes at least: information on changes in the external temperature and humidity of the product during storage.

[0151] Specifically, based on the actual production, transportation, storage, and sales time and location of the product, the external temperature and humidity change curves experienced by the product are obtained, covering diurnal temperature differences during transportation, seasonal fluctuations in the storage environment, and sudden climate disturbances. This can be achieved by deploying environmental monitoring nodes or accessing historical meteorological databases to obtain temperature and humidity time-series data for at least seven consecutive days. The data sampling frequency can be selected to be no less than once per hour. After standardization, the data is coupled with the product's moisture adsorption isotherm to quantify the dynamic driving intensity of external water vapor disturbances on the microenvironment inside the packaging. For example, if the product is produced in Shanghai and is expected to be sold in Hangzhou, hourly temperature and humidity data measured by meteorological stations along the Shanghai-Hangzhou route over the past 30 days are obtained to form temperature and humidity change curves.

[0152] In practical applications, in order to obtain relevant environmental information, historical environmental information can be used to predict the storage environment information within the subsequent storage period.

[0153] Step S2: Obtain the target humidity range inside the product packaging;

[0154] Based on the actual properties of the product and its storage environment requirements, the target humidity range that needs to be maintained inside the product packaging is obtained. Specifically, in practical applications, the target humidity range inside the product packaging is expressed as water vapor partial pressure or humidity ratio. This embodiment uses water vapor partial pressure as an example for explanation. Let e_in = a_in·e_s(T_in), that is, at time t, e_in(t) = a_in(t)·e_s(T_in), where e_in(t) is the water vapor partial pressure inside the product packaging at time t, a_in is the water activity inside the product packaging, T_in is the temperature inside the product packaging, and e_s(T_in) is the saturated water vapor pressure at temperature T_in inside the product packaging. Therefore, in the actual product packaging process, the water activity range for product storage inside the packaging is usually agreed upon. For example, the water activity requirement for biscuit and cookie products is 0.2-0.4, and the water activity requirement for cake products is greater than 0.8.

[0155] In practical applications, the allowable fluctuation range of the water vapor partial pressure e_in inside the product packaging can be determined based on the product's water activity (a) safety threshold and shelf-life kinetic model. min ,e maxFor example, for instant oatmeal with a moisture content of 45%, its safe threshold for water activity is a≤0.65, corresponding to a saturated water vapor pressure at 25℃ e_s=3.169kPa, from which we can obtain e max =0.65×3.169≈2.06kPa; e min The setting is based on the critical point for preventing dehydration. For example, if it is set to the minimum water vapor partial pressure required to prevent textural hardening, such as 0.8 kPa, then [e] min ,e max = [0.8, 2.06] kPa; This range drifts dynamically with temperature, and e_s(T) needs to be calibrated across the entire temperature range and mapped to the corresponding a limit.

[0156] Step S3: Obtain the equivalent exchange coefficient based on the airtightness quantification of the product packaging;

[0157] Obtain the product's current packaging form, such as boxed or bagged packaging, and calibrate its equivalent exchange coefficient k_e based on its structural characteristics and sealing process through standard leak rate testing or accelerated damp heat cycling testing; for example, for sealed boxes with adhesive strips, the k_e value is typically 0.8–1.2h. -1 The snap-fit ​​enclosure is 1.5–2.3h. -1 The sealing tape corresponds to k_e≈0.3–0.6h. -1 For valve-type structures, the k_e values ​​need to be calibrated in different open and closed states. A mapping relationship between k_e and structural parameters (such as seal line length, contact surface roughness, and adhesive layer thickness) needs to be established to provide a traceable engineering basis for subsequent parameter coupling. In practical applications, the equivalent exchange coefficient is defined as the equivalent air exchange rate or time constant.

[0158] Step S4: Obtain the humidity conditioning material setting scheme for the product packaging, and obtain the equivalent humidity conditioning coefficient based on the humidity conditioning material setting scheme;

[0159] The equivalent humidity control coefficient is obtained based on the combined effects of packaging material moisture permeability, effective area, layout, and gas phase mixing.

[0160] In practical applications, while keeping the material structure and coating method unchanged, K_m can be approximately positively correlated with the effective moisture permeability area A and the dosage M of the material, and inversely correlated with the head space volume V:

[0161] K_m ≈ α·(M / V) or K_m ≈ β·(A / V)

[0162] α and β are calculated from the calibration test over a period of about one week and are the equivalent strength coefficients corresponding to the unit amount of material applied. When the moisture permeability or geometric area A of the covering material is changed, K_m will change accordingly.

[0163] When A is reached, K_m will change accordingly.

[0164] Therefore, for any new effective permeable area A', product packaging volume V', and material dosage M', it can be predicted that: K_m'=α·(M' / V'), or K_m'≈β·(A' / V'), and combined with the already calibrated k_e (or the new k_e'), a 5-10 day prediction and a_w inverse solution can be performed.

[0165] The selection of the humidity-regulating material should meet the following requirements: the material is in a reversible moisture absorption and release range within the predicted upper limit of the actual product shelf life, and is not close to the capacity limit.

[0166] Step S5: Construct a fitted dynamic prediction model and couple the saved environmental information, internal target humidity range, equivalent humidity regulation coefficient, and equivalent exchange coefficient into the input to obtain the time when the humidity inside the product packaging exceeds the target humidity range.

[0167] The fitted dynamic prediction model is as follows:

[0168] de_in / dt = k_e(T_bar, a_bar) · (e_out - e_in) - K_m(T_in, a_in) · (e_in - e_set)

[0169] Where, a_in = RH_in / 100, a_out = RH_out / 100, T_bar = (T_in + T_out) / 2, a_bar = (a_in + a_out) / 2, e_in = a_in·e_s(T_in), e_out = a_out·e_s(T_out), e_set(T_in) = a_w·e_s(T_in); e_in(t) is the partial pressure of water vapor inside the product packaging at time t; e_out(t) is the partial pressure of water vapor outside the product packaging at time t; T represents temperature, T_in is the internal temperature of the product packaging, T_out is the external ambient temperature of the product packaging; e_s(T) is the saturated water vapor pressure at temperature T, and e_s(T_out) is the saturated water vapor pressure at external temperature T_out. Saturated vapor pressure, e_s(T_in) is the saturated vapor pressure at the internal temperature T_in; e_set(t) is the set partial pressure of the material at time t, which is determined by the material a_w and the internal temperature T_in of the product packaging, i.e., e_set(t) = a_w·e_s(T_in(t)), e_set(T_in) is the set partial pressure of the material at the internal temperature T_in at time t; a_w is the water activity of the material, a_in is the water activity inside the product packaging, and a_out is the water activity of the external environment of the product packaging; K_m is the equivalent humidity regulation coefficient; k_e is the equivalent exchange coefficient; de_in / dt is the rate of change of the partial pressure of water vapor inside the product packaging with time t; RH is the relative humidity, RH_in is the relative humidity inside the product packaging, and RH_out is the relative humidity outside the product packaging.

[0170] The specific method for constructing the dynamic prediction model is as follows:

[0171] First, assuming a fixed product packaging volume V, the effect of changes in the total air volume inside the packaging on the partial pressure of water vapor is negligible; airtightness is represented by an equivalent exchange coefficient (including the combined effects of permeation, micro-leakage, and breathing effect); the humidity-regulating material can be considered as a "buffer" that pulls the partial pressure inside the product packaging back to its set partial pressure e_set, and the equivalent humidity-regulating intensity is represented by the coefficient K_m; the product packaging and material performance do not undergo irreversible degradation in the short term (approximately one week); if degradation occurs, a retest and correction can be performed in the second week. The selection of the humidity-regulating material should meet the following requirements: the material is in a reversible moisture absorption and release operating range within the target shelf life, and does not approach its capacity limit within the shelf life.

[0172] When the external environment can be considered approximately stable within a 5–10 day window (or replaced by a window average), the steady-state partial pressure of equation (1) is:

[0173] e*=(k_e·e_out+K_m·e_set) / (k_e+K_m) Formula (2)

[0174] If the product packaging is required to maintain a target humidity range (RH_tar, e.g., 62%RH), the target partial pressure can be obtained first:

[0175] e_tar=RH_tar·e_s(T_in) Formula (3)

[0176] The required partial pressure of the material is obtained by inverse solution of equation (2):

[0177] e_set=e_tar+(k_e / K_m)·(e_tar-e_out) Formula (4)

[0178] Then calculate the water activity of the material:

[0179] a_w=e_set / e_s(T_in) Equation (5)

[0180] The more humid the outside environment (the larger e_out), the lower a_w is required; the less airtight the enclosure (the larger k_e), the stronger the material is required (a larger K_m, or a lower a_w).

[0181] The equivalent humidity control coefficient K_m is obtained based on the combined effects of packaging material moisture permeability, effective area, layout, and gas phase mixing.

[0182] Step S6: Obtain the actual shelf life of the product based on the time of the expiration.

[0183] In practical applications, the upper limit of the predicted shelf life of the actual product is less than or equal to 90 days.

[0184] In practical applications, the packaging structure or sealing condition of the product packaging remains stable within the predicted upper limit of the actual product shelf life.

[0185] The total weight W(t) of the product packaging is collected in real time by a weighing sensor, and W(t) is aligned with the internal temperature and humidity of the product packaging, as well as the external temperature and humidity of the product packaging, at the same timestamp or on a uniformly mapped time axis.

[0186] Calculated based on the total packaging weight W_test(t) of the experimental group and the total packaging weight W_blank(t) of the blank control group:

[0187] Δ_net(t) = [W_test(t) - W_test(0)] - [W_blank(t) - W_blank(0)], and calculate J_net(t) = dΔW_net(t) / dt to obtain the real-time moisture mass flux of the packaging system. Where W_Test(t) is the total weight of the test package containing the sample and / or conditioning material, W_blank(t) is the total weight of the blank control package, and J_net(t) is the net moisture mass flux after deducting blank drift.

[0188] The cumulative moisture load q(t) or cumulative moisture absorption load q_abs(t) is obtained by integrating J_net(t), and the capacity consumption rate of the humidity conditioning material is determined by q(t) / C_effective or q_abs(t) / C_effective, where C_effective is the effective working capacity of the humidity conditioning material within the product's allowable humidity range.

[0189] When J_net(t) and e_out(t)-e_in(t) change synchronously in time, it can be used to enhance the identification of the equivalent exchange coefficient k_e on the packaging side; when RH_in(t) remains stable while ΔW_net(t) continues to increase, it indicates that external moisture is entering the packaging and being absorbed by the humidity conditioning material or product, and the capacity consumption rate of the humidity conditioning material can be further calculated.

[0190] For a 7-day short-term verification window, q_7d=∫_0^7d J_net(t)dt or q_abs,7d=∫_0^7d max[J_net(t),0]dt can be calculated, and q_7d / C_effective or q_abs,7d / C_effective can be used as the effective capacity consumption rate of the material.

[0191] Wherein, C_effective is the effective moisture absorption or release capacity of the humidity-regulating material within the product's allowable humidity window, rather than the material's fully saturated capacity; when the capacity consumption rate exceeds the preset threshold, even if RH_in(t) is still within the target range, it should be determined that the packaging scheme has a risk of insufficient capacity margin.

[0192] The remaining capacity C_rema_ining(t) = C_effective - q_abs(t) is obtained based on the capacity consumption rate, and the capacity failure time t_capacity_fail is determined when the remaining capacity is lower than the preset threshold, the equivalent humidity coefficient K_m decays, or the humidity inside the product packaging rebounds.

[0193] The time when the internal humidity of the packaging exceeds the target humidity range (t_RH_fail) is compared with the capacity failure time (t_capacity_fail), and the actual shelf life or storage and transportation risk warning of the product is obtained based on the earlier occurrence time.

[0194] In practical applications, the specific process of this embodiment is as follows:

[0195] enter:

[0196] External conditions: T_out(t), RH_out(t) (or window statistics provided for 5–10 days);

[0197] Target: RH_tar (e.g., 62%) and allowable fluctuation range ±ΔRH;

[0198] Time window: 5–10 days;

[0199] Parameters: k_e (box airtightness, also known as equivalent exchange coefficient, from control group calibration), K_m (material equivalent humidity regulation coefficient, from experimental group calibration), material dosage M, and product packaging volume V.

[0200] step:

[0201] 1) Calculate the partial pressure of water vapor outside the product packaging at time t, e_out(t) = RH_out·e_s(T_out), and the representative value of the internal temperature of the product packaging, T_in (which can be the time average of Test or the critical operating point).

[0202] 2) The material strength, i.e. the equivalent moisture regulation coefficient K_m, is calculated using K_m=α(M / V);

[0203] 3) The water activity a_w of the candidate material is obtained by using the steady-state inverse solution (Equation 4–5);

[0204] 4) Use the dynamic model (Equation 1) to perform a 5-10 day simulation. Input the partial pressure of water vapor inside the product packaging e_out(t) and the temperature inside the product packaging T_in(t) at time t. Check whether the relative humidity RH_in(t) inside the product packaging at time t falls within the target range, or judge whether the simulation prediction meets the requirements based on the judgment criteria.

[0205] Alternatively, calculate the cumulative moisture load q(t) = ∫J_net(t)dt or the cumulative moisture absorption load q_abs(t) = ∫max[J_net(t),0]dt within the target shelf life based on the real-time quality flux, and obtain the capacity consumption rate q(t) / C_effective or q_abs(t) / C_effective by combining it with the effective working capacity C_effective of the humidity conditioning material; obtain the remaining capacity C_rema_ining(t) = C_effective - q_abs(t) based on the capacity consumption rate, and determine the capacity failure time t_capacity_fail when C_rema_ining(t) is lower than the preset threshold or the equivalent humidity conditioning coefficient K_m decays; compare the time t_RH_fail when the humidity inside the product packaging exceeds the target humidity range with the capacity failure time t_capacity_fail, and take the earlier of the two times as the risk failure time of the packaging and storage plan;

[0206] 5) If not satisfied: the time when the condition is not met shall be taken as the time of failure, and the time period from the product start time to the time of failure shall be taken as the reference value of the actual shelf life of the product. The actual shelf life of the product shall be less than or equal to the reference value.

[0207] 6) Prioritize adjusting the water activity of the material a_w; or further adjust the amount of material added M (improved through K_m), or improve the airtightness (reducing k_e).

[0208] In this embodiment, the failure time under different packaging scheme changes can be simulated and predicted multiple times through steps 4), 5), and 6), that is, a_w, K_m, and k_e are adjusted to generate different packaging schemes. Then, the actual shelf life of different packaging schemes is given based on the simulation prediction results.

[0209] In practical applications, the judgment criteria for determining whether simulation prediction meets the requirements are designed and formulated based on the actual product. This embodiment is only an example. For instance, the judgment criteria shown in Table 1 of Embodiment 1 can be used to determine whether the requirements are met.

[0210] In practical applications, different product judgment indicators can be set according to different product types, as shown in Table 2 of Example 1.

[0211] Step S7: Select a packaging scheme whose actual shelf life is greater than or equal to the target shelf life based on the preset target shelf life.

[0212] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for obtaining the actual shelf life of a product based on its packaging and surrounding environment, characterized in that, The method includes the following steps: Obtain information about the storage environment where the product is located; Obtain the target humidity range inside the product packaging; Obtain the equivalent exchange coefficient based on the airtightness quantification of product packaging; Obtain the humidity conditioning material setting scheme for the product packaging, and obtain the equivalent humidity conditioning coefficient based on the humidity conditioning material setting scheme; A fitting dynamic prediction model is constructed and the stored environmental information, internal target humidity range, equivalent humidity regulation coefficient, and equivalent exchange coefficient are coupled as inputs to obtain the time when the humidity inside the product packaging exceeds the target humidity range. The actual shelf life of the product is obtained based on the time of the failure.

2. The method for obtaining the actual shelf life of a product based on its packaging and environment according to claim 1, characterized in that, The storage environment information includes at least: information on changes in the external temperature and humidity of the product during storage.

3. The method for obtaining the actual shelf life of a product based on its packaging and environment according to claim 1, characterized in that, The equivalent exchange coefficient is defined as the equivalent number of air exchanges or the time constant.

4. The method for obtaining the actual shelf life of a product based on its packaging and environment according to claim 1, characterized in that, The target humidity range in the obtained target humidity range inside the product packaging is expressed as water vapor partial pressure or humidity ratio.

5. The method for obtaining the actual shelf life of a product based on its packaging and environment according to claim 1, characterized in that, The equivalent humidity control coefficient is obtained based on the combined effects of packaging material moisture permeability, effective area, layout, and gas phase mixing.

6. The method for obtaining the actual shelf life of a product based on its packaging and environment according to claim 1, characterized in that, The predicted upper limit for the actual product shelf life is less than or equal to 90 days.

7. The method for obtaining the actual shelf life of a product based on its packaging and environment according to claim 1, characterized in that, The step of obtaining the humidity-regulating material setting scheme for the product packaging and obtaining the equivalent humidity-regulating coefficient based on the humidity-regulating material setting scheme includes: having a preset reference library of humidity-regulating material setting schemes and equivalent humidity-regulating coefficients, and obtaining the equivalent humidity-regulating coefficient based on the reference library after obtaining the humidity-regulating material setting scheme.

8. The method for obtaining the actual shelf life of a product based on packaging and its environment according to any one of claims 1 to 7, characterized in that, The fitted dynamic prediction model is as follows: de_in / dt = k_e(T_bar, a_bar) · (e_out - e_in) - K_m(T_in, a_in) · (e_in - e_set) Where, a_in = RH_in / 100, a_out = RH_out / 100, T_bar = (T_in + T_out) / 2, a_bar = (a_in + a_out) / 2, e_in = a_in·e_s(T_in), e_out = a_out·e_s(T_out), e_set(T_in) = a_w·e_s(T_in); T_in is the internal temperature of the product packaging, T_out is the external ambient temperature of the product packaging; e_s(T_out) is the external temperature T_ saturated vapor pressure at temperature T_in; e_s(T_in) is the saturated vapor pressure at internal temperature T_in; e_set(T_in) is the set partial pressure of the material at internal temperature T_in at time t; a_w is the water activity of the material; a_in is the water activity inside the product packaging; a_out is the water activity of the external environment of the product packaging; K_m is the equivalent humidity control coefficient; k_e is the equivalent exchange coefficient; de_in / dt is the rate of change of the partial pressure of water vapor inside the product packaging with time t; RH_in is the relative humidity inside the product packaging; RH_out is the relative humidity outside the product packaging.

9. The method for obtaining the actual shelf life of a product based on its packaging and environment according to claim 6, characterized in that, The selection of the humidity-regulating material should meet the following requirements: the material is in a reversible moisture absorption and release range within the predicted upper limit of the actual product shelf life, and is not close to the capacity limit.

10. The method for obtaining the actual shelf life of a product based on its packaging and environment according to claim 6, characterized in that, Within the predicted upper limit of the actual product shelf life, the packaging structure or sealing condition of the product packaging remains stable.