A method for determining the action threshold of tobacco moisture preservative based on double tangent method

Abstract

The application discloses a method for determining a tobacco humectant action threshold based on a double tangent method, and belongs to the technical field of tobacco humectants. The method for determining the action threshold is as follows: the equilibrium moisture content of cut tobacco to which different concentration gradient humectants are applied under specific storage conditions is determined; the humectant application amount is taken as an independent variable, and the equilibrium moisture content is taken as a dependent variable, so that a first relationship curve is fitted; the first relationship curve is differentiated to obtain a relationship curve between the equilibrium moisture content change rate and the humectant application amount, which is recorded as a second relationship curve; tangent lines are drawn at the starting end and the ending end of the second relationship curve, and the humectant application amount corresponding to the intersection point of the two tangent lines is determined as the humectant action threshold. The application avoids subjectivity of relying on sensory evaluation or experience adjustment, realizes objective and quantitative determination of a critical humectant addition amount, and provides clear technical reference for balancing the humectant effect and the humectant cost.

Description

Technical Field

[0001] This invention relates to the field of tobacco humectant technology, and in particular to a method for determining the action threshold of tobacco humectants based on the double tangent method. Background Technology

[0002] In the tobacco processing industry, humectants are widely used to improve the water-holding capacity and processing resistance of raw materials. Existing technologies mainly focus on evaluating and comparing the humectant performance of humectants, i.e., determining which humectant is more effective, or measuring the content of humectants in tobacco. For the same humectant, the relationship between its application amount and humectant effect is not a simple linear one: too small an application amount results in insufficient humectant effect, while too large an application amount leads to diminishing marginal returns, resulting in increased costs with limited benefit. In practice, determining the amount of humectant added often relies on sensory evaluation or empirical adjustments. These methods are highly subjective, making it difficult to establish unified quantitative standards and accurately capture the dynamic inflection point of humectant effect changes with application amount. How to objectively and quantitatively determine a critical addition amount that balances humectant effect and application amount economy is a problem urgently needing to be solved in actual production. Summary of the Invention

[0003] In view of this, the present invention provides a method for determining the action threshold of tobacco humectants based on the double tangent method, aiming to solve the problem in the prior art that it is impossible to objectively and quantitatively determine the critical amount of humectants to be added for economic efficiency.

[0004] In a first aspect, the present invention provides a method for determining the action threshold of tobacco humectants based on the double tangent method, comprising the following steps: The equilibrium moisture content of tobacco shreds treated with different concentration gradient humectants was determined under specific storage conditions. Using the amount of humectant applied as the independent variable and the equilibrium moisture content as the dependent variable, the first relationship curve was obtained by fitting the data. Differentiating the first relationship curve yields the relationship curve between the rate of change of equilibrium moisture content and the amount of moisturizing agent applied, which is denoted as the second relationship curve. Tangents are drawn at the starting and ending points of the second relationship curve, and the amount of moisturizing agent applied at the intersection of the two tangents is determined as the threshold of moisturizing agent action.

[0005] Preferably, the humectant includes at least one of propylene glycol, glycerin, and sorbitol.

[0006] Preferably, the specific storage conditions are a constant temperature and relative humidity environment; when determining the equilibrium moisture content, the equilibrium is maintained for more than 45 hours under the specific storage conditions.

[0007] Preferably, the fitting function for the first relationship curve is selected from a logarithmic function, an exponential saturation function, a power function, or the Michaelis equation.

[0008] Furthermore, by comparing the correlation coefficients (R²) of different fitting functions... 2 ) and chi-square value (χ) 2 To select the optimal fitting function.

[0009] Preferably, the amount of the humectant applied is 0-5 wt%, based on the weight of the tobacco shreds.

[0010] Preferably, the starting point and the ending point of the second relationship curve are the minimum amount of humectant applied and the maximum amount of humectant applied, respectively.

[0011] Secondly, the present invention provides a system for determining the action threshold of tobacco humectants based on the double-tangent method, comprising: The equilibrium moisture content measurement module is used to measure the equilibrium moisture content of tobacco shreds with different concentration gradient humectants under specific storage conditions. The curve fitting module is used to fit the first relationship curve with the amount of humectant applied as the independent variable and the equilibrium moisture content as the dependent variable. The differentiation module is used to differentiate the first relationship curve to obtain the second relationship curve; The threshold calculation module is used to draw tangents at the starting and ending points of the second relationship curve, and determine the amount of moisturizer applied at the intersection of the two tangents as the moisturizer action threshold.

[0012] Thirdly, the present invention provides an electronic device including a processor and a memory, the memory storing a computer program, wherein the processor executes the computer program to implement the steps of the above-described method.

[0013] Fourthly, the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the above-described method.

[0014] Compared with the prior art, the present invention has achieved the following beneficial effects: This invention measures the equilibrium moisture content of tobacco shreds treated with different concentration gradient humectants and establishes a fitting curve between the equilibrium moisture content and the applied amount. The differential of the fitting curve yields the equilibrium moisture content change rate curve. Tangents are then drawn at both ends of this curve, and the intersection points are used to determine the humectant's effect threshold. This quantifies the marginal benefit inflection point of the humectant into a specific applied amount, avoiding subjectivity based on sensory evaluation or experience-based adjustments. It achieves objective and quantitative determination of the critical addition amount of the humectant. This threshold accurately reflects the transition point from significant increase to a decreasing rate of increase in humectant application, providing a clear technical reference for balancing humectant effectiveness and humectant cost. Attached Figure Description

[0015] The accompanying drawings, which form part of this specification, are used to provide a further understanding of the invention. The illustrative embodiments and descriptions of the invention are used to explain the invention and do not constitute an undue limitation thereof. Obviously, those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0016] Figure 1 This is the first relationship curve in Example 1 of the present invention when propylene glycol is used as a humectant, with an exponential saturation function as the fitting equation; Figure 2 This is the second relationship curve in Embodiment 1 of the present invention; Figure 3 This is the first relationship curve in Example 2 of the present invention when glycerin is used as a humectant, and the Michaelis equation is used as the fitting equation; Figure 4 This is the second relationship curve in Embodiment 2 of the present invention. Detailed Implementation

[0017] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0018] In tobacco processing, the amount of humectant applied directly affects the water-holding capacity of tobacco, processing losses, and the sensory quality of the final product. Existing technologies mostly focus on horizontal comparisons of humectant performance or content determination, lacking objective and quantitative methods for determining the economically optimal addition amount of the same humectant. In practice, sensory evaluation or empirical adjustments are often relied upon, making it difficult to accurately capture the marginal inflection point of humectant effect changes with application amount. Therefore, this invention provides a method for determining the action threshold of tobacco humectants based on the double-tangent method and its application. By measuring the change in equilibrium moisture content with the amount of humectant applied, the critical addition amount is determined using differential and double-tangent methods, providing a basis for the scientific control of humectant application amount.

[0019] This invention provides a method for determining the action threshold of tobacco humectants based on the double tangent method. The core idea of ​​this method is to establish a quantitative relationship between the amount of humectant applied and the equilibrium moisture content of tobacco, and further analyze the rate of change of equilibrium moisture content with the increase of the amount applied. The double tangent method is used to identify the turning point of diminishing marginal benefits, and the amount of application corresponding to the turning point is determined as the action threshold of the humectant.

[0020] Specifically, the method includes the following steps: Step S1: Determine the equilibrium moisture content of tobacco shreds treated with different concentration gradient humectants under specific storage conditions.

[0021] In this step, the humectant to be tested is first selected and uniformly applied to the tobacco raw material at different mass percentages. The type of tobacco can include, but is not limited to, one or more of the following: leaf shreds, stem shreds, sheet shreds, and reconstituted tobacco shreds. The type of humectant can include, but is not limited to, at least one of the following: propylene glycol, glycerin, and sorbitol, or any mixture of the above in any proportion.

[0022] The selection of different concentration gradients should cover the conventional addition range from low to high. Based on the weight of the tobacco shreds, the application range of the humectant is typically 0–5 wt%, meaning the mass percentage of the humectant relative to the tobacco shreds is 0–5%. In practice, multiple gradient points can be set, such as 0.05%, 0.50%, 1.00%, 2.00%, 3.00%, and 4.00%, etc. The specific number of gradients and intervals can be adjusted according to the type of humectant and the expected effect.

[0023] After applying the humectant, the tobacco is placed under specific storage conditions for equilibration. These specific storage conditions refer to a constant temperature and relative humidity environment, used to simulate typical working conditions during tobacco processing or storage. Under these conditions, the equilibration time is typically 45 hours or more, preferably 48 hours, to ensure that the internal moisture of the tobacco reaches equilibrium.

[0024] The equilibrium moisture content can be determined using methods known in the art, such as the oven drying method, preferably according to YCT31-1996 "Preparation and Moisture Determination of Tobacco and Tobacco Product Samples - Oven Drying Method". The specific procedure is as follows: accurately weigh a certain mass of equilibrium tobacco shreds, dry them in an oven at approximately 100°C until constant weight, and calculate the moisture content based on the mass difference before and after drying. To improve the accuracy of the determination, multiple parallel samples can be set up for each gradient, and the average value is taken as the equilibrium moisture content for that gradient.

[0025] Step S2: Using the amount of humectant applied as the independent variable and the equilibrium moisture content as the dependent variable, fit the first relationship curve.

[0026] The multiple sets of data (the amount of moisturizing agent applied, x, and the equilibrium moisture content, y) obtained in step S1 are plotted as a scatter plot. Then, a suitable function model is selected for nonlinear fitting to obtain a smooth curve that reflects the trend of equilibrium moisture content with the amount of application. This curve is denoted as the first relationship curve.

[0027] The fitting function should be chosen to describe the saturated growth characteristic that "as the applied amount increases, the equilibrium moisture content gradually increases, but the rate of increase gradually slows down." Suitable fitting functions include, but are not limited to, the following: Logarithmic function: y = a + b·ln(x), where a and b are fitting parameters, suitable for cases with rapid growth and gradual flattening at low application levels.

[0028] Exponential saturation function: y = a - b·e -kx , where a, b, and k are fitting parameters. This function has asymptotes and can describe the growth process approaching saturation.

[0029] Power function: y = a + b·x n , where a, b, and n are fitting parameters, and n is usually less than 1 to indicate a decreasing growth rate.

[0030] The Michaelis-Menten equation (y = a + (b·x) / (c + x)) is derived from enzyme kinetics and is excellent at describing physicochemical processes with saturation characteristics.

[0031] In practical fitting, the least squares method or other optimization algorithms can be used to compare the correlation coefficients (R²) of different functions. 2 ) and chi-square value (χ) 2 The optimal fitting model is selected by using a correlation coefficient closest to 1 and a chi-square value that is the smallest. This is typically chosen as the final first relationship curve.

[0032] Step S3: Differentiate the first relationship curve to obtain the relationship curve between the equilibrium moisture content change rate and the amount of moisturizing agent applied, which is denoted as the second relationship curve.

[0033] The first relationship curve y = f(x) describes the change in the absolute value of the equilibrium moisture content with the amount of moisturizer applied, x. Taking its first derivative dy / dx = f'(x), the resulting derivative function represents the increase in equilibrium moisture content caused by a unit increase in the amount of moisturizer applied, i.e., the "rate of change in equilibrium moisture content". Using the amount of moisturizer applied, x, as the independent variable and the derivative value dy / dx as the dependent variable, the resulting curve is the second relationship curve.

[0034] The physical significance of the second relationship curve lies in its direct reflection of the diminishing marginal benefit of the humectant (i.e., the increase in moisture content obtained by increasing the amount of humectant applied) as the application rate increases. Typically, the derivative value is large when the application rate is small; as the application rate increases, the derivative value gradually decreases and approaches zero.

[0035] It is important to note that if tangents are directly drawn to both ends of the first relationship curve (i.e., the fitted curve of equilibrium moisture content versus the amount of humectant applied), the intersection of these tangents corresponds to the application amount where the absolute value of the equilibrium moisture content approaches saturation. This point reflects the saturation point where "the moisture content essentially no longer increases." Near this point, further increasing the amount of humectant can no longer significantly improve the moisture content, but at this point, the amount of humectant used is often too high, resulting in poor economic efficiency. This invention, however, differentiates the first relationship curve to obtain the second relationship curve (i.e., the equilibrium moisture content change rate curve), and then draws tangents to both ends of this curve. The intersection corresponds to the critical point where the marginal benefit of the humectant transitions from significant to diminishing. The application amount at this intersection is usually significantly lower than the saturation point of the former, indicating earlier the point where the effect gain from a unit increase in humectant begins to decline rapidly, thus better balancing the humectant effect and application cost.

[0036] The differential of the fitted curve can be obtained by analytical differentiation: if the first relationship curve is an explicit function expression (such as an exponential saturated function or the Michaelis equation), the derivative function can be obtained by directly differentiating it; if the fitting is in numerical form, the derivative value at each point can be approximately calculated by the difference method, and then interpolated to obtain a continuous second relationship curve.

[0037] Step S4: Draw tangents at the starting and ending points of the second relationship curve, and determine the amount of humectant applied at the intersection of the two tangents as the humectant action threshold.

[0038] The second relationship curve is typically a monotonically decreasing curve with a downward convexity (convex function). Its starting point corresponds to the minimum amount of humectant applied (usually 0 or close to 0), and its ending point corresponds to the maximum amount of humectant applied (e.g., 5 wt%). Tangents to the curve are drawn at the starting and ending points, and these two tangents intersect at a point below (or above) the curve.

[0039] When drawing the graph, first calculate the starting point (x). min The derivative of f'(x) min ), obtain the slope of the tangent line at that point, passing through the point (x min , f'(x min Draw a straight line; similarly, calculate the endpoint (x). max The derivative of f'(x) max ), passing through point (x) max , f'(x max Draw another straight line. Find the intersection of the two straight lines. The x-coordinate of the intersection point (i.e., the amount of moisturizer applied) is the desired threshold value.

[0040] Mathematically, this intersection point corresponds to the location on the second relationship curve where the curvature change is most significant; economically, it corresponds to the turning point where marginal benefits begin to decline rapidly. In practical applications, this threshold can serve as a critical economic reference value for the amount of humectant applied: when the application amount is below this threshold, increasing the humectant can significantly improve the equilibrium moisture content of the tobacco, resulting in a high effect per unit cost; when the application amount exceeds this threshold, the effect of further increasing the humectant on improving the equilibrium moisture content gradually weakens, marginal benefits decrease, and economic efficiency deteriorates.

[0041] Preferably, the starting and ending points of the second relationship curve are the minimum and maximum application amounts of the wetting agent, respectively. The minimum application amount is typically 0 wt% (blank control), and the maximum application amount is set according to actual process requirements, generally 3 wt%, 4 wt%, or 5 wt%. It should be noted that if the application amount corresponding to the intersection of the two tangents is greater than the measured maximum gradient, it indicates that no obvious marginal effect inflection point has appeared within the measured range, and the gradient range should be expanded and remeasured; if the intersection point is less than the minimum gradient, the minimum gradient or its nearby value can be used as the reference lower bound of the effect threshold.

[0042] The present invention also provides a system for determining the action threshold of tobacco humectants based on the double tangent method.

[0043] This system is used to execute the above methods, and the functions of its various modules correspond to the steps of the methods described above. The system includes: an equilibrium moisture content determination module, a curve fitting module, a differentiation module, and a threshold calculation module.

[0044] The equilibrium moisture content determination module is used to determine the equilibrium moisture content of tobacco shreds treated with different concentration gradient humectants under specific storage conditions. This module may include hardware units such as a constant temperature and humidity chamber (to provide specific storage conditions), a balance, and an oven, as well as a data recording and processing unit. This module can automatically or semi-automatically determine the equilibrium moisture content of tobacco shred samples under different humectant application amounts and output the data in a structured format (such as a table).

[0045] The curve fitting module is used to fit the first relationship curve with the amount of humectant applied as the independent variable and the equilibrium moisture content as the dependent variable. This module receives data pairs from the equilibrium moisture content determination module, has built-in various fitting functions (logarithmic function, exponential saturation function, power function, Michaelis-Menten equation, etc.), and uses optimization algorithms such as the least squares method to calculate the fitting parameters. At the same time, it outputs evaluation indicators such as the correlation coefficient and chi-square value of each fitting model, allowing users to select the optimal fitting curve.

[0046] The differentiation module is used to differentiate the first relationship curve to obtain the second relationship curve. This module receives the first relationship curve expression output by the curve fitting module, performs analytical or numerical differentiation on it, and generates a set of data points or a function expression reflecting the change rate of equilibrium moisture content with the amount of wetting agent applied, i.e., the second relationship curve.

[0047] The threshold calculation module is used to draw tangents at the start and end points of the second relationship curve, and determine the amount of moisturizer applied corresponding to the intersection of the two tangents as the moisturizer's effect threshold. This module first identifies the minimum and maximum independent variable endpoints of the second relationship curve, calculates the derivative values ​​at each endpoint, then constructs the equations of the two tangents, solves for the coordinates of the intersection point, and outputs the x-coordinate of the intersection point as the final effect threshold. This module may also include an anomaly handling submodule to determine whether the intersection point falls within a reasonable range and provide corresponding prompts or suggestions.

[0048] The modules described above can be integrated into a single physical device or distributed across different devices, working collaboratively via communication connections. The system can be implemented using software, hardware, or a combination of both.

[0049] The present invention also provides an electronic device comprising a processor and a memory. The memory stores a computer program, and the processor executes the computer program to implement the steps of the above-described method.

[0050] The processor can be a central processing unit (CPU), digital signal processor (DSP), application-specific integrated circuit (ASIC), field-programmable gate array (FPGA), or other programmable logic device. The memory can be a read-only memory (ROM), random access memory (RAM), flash memory, hard disk, optical disk, or other storage media, used to store program instructions and related data. Data exchange between the processor and memory occurs via a bus or other communication interface.

[0051] When the electronic device is running, the processor reads the computer program from the memory and performs the following operations: acquires the equilibrium moisture content data of tobacco shreds under different amounts of humectant; performs curve fitting; calculates the derivative to obtain the second relationship curve; calculates the intersection of the two tangents and outputs the action threshold. The electronic device may also include input / output interfaces for receiving experimental data input by the user, setting parameters (such as the type of fitting function, gradient range, etc.), and displaying or printing the final action threshold result.

[0052] The present invention also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, performs the steps of the above-described method. The computer-readable storage medium can be any medium capable of storing program code, such as a USB flash drive, portable hard drive, read-only memory, random access memory, magnetic disk, optical disk, etc. This medium can be applied to various computing devices, enabling the devices to execute the methods of the present invention.

[0053] This invention, through fitting, differentiation, and calculation of the intersection of two tangents in the relationship between the amount of humectant applied and the equilibrium moisture content, achieves for the first time an objective and quantitative determination of the threshold effect of tobacco humectants. This overcomes the limitations of traditional sensory evaluation or empirical methods and provides a scientific basis for the precise application of humectants in tobacco processing. The method, system, electronic equipment, and storage medium described herein have the advantages of high versatility and accuracy, and can be applied to threshold determination under different types of humectants and different environmental conditions.

[0054] The technical solution of the present invention will be further described below with reference to specific embodiments. The present invention does not impose any special restrictions on the source of reagents used in the following embodiments; commercially available products well known to those skilled in the art can be used.

[0055] Example 1 This embodiment provides the determination of the action threshold of propylene glycol as a humectant under standard environmental conditions.

[0056] (1) Application of humectant and sample preparation: Propylene glycol was uniformly applied to the formulated tobacco shreds at different concentration gradients. Based on the weight of the tobacco shreds, the application amounts of propylene glycol were 0.05 wt%, 0.50 wt%, 1.00 wt%, 2.00 wt%, 3.00 wt%, and 4.00 wt%.

[0057] (2) Determination of equilibrium moisture content: The tobacco shreds with different concentration gradient humectants were placed under standard equilibrium conditions (temperature 22℃, relative humidity 60%) for 48 hours, and the equilibrium moisture content of each sample was determined by oven drying method (refer to YC / T 31-1996).

[0058] (3) Fitting the first relationship curve: Plot a scatter plot with the amount of moisturizing agent applied as the independent variable x and the equilibrium moisture content as the dependent variable y. The logarithmic function y=a+b·lnx and the exponential saturation function y=ab·e are used respectively. -kx Power function y = a + b·x n The Michaelis equation y = a + (b·x) / (c + x) was fitted. The fitting results are shown in Table 1. Among them, the exponential saturation function had the highest correlation coefficient (R²). 2 =0.9969), the chi-square minimum (χ²) 2=0.00124), therefore, the exponential saturation function is chosen as the fitting equation for the first relationship curve, as follows. Figure 1 As shown.

[0059] Table 1. Correlation coefficients and chi-square values ​​for different fitting equations

[0060] (4) Obtain the second relationship curve by taking the differential: Take the first derivative of the above exponential saturation function to obtain the relationship curve between the rate of change of equilibrium moisture content and the amount of moisturizing agent applied (the second relationship curve), as shown in the figure. Figure 2 As shown.

[0061] (5) Determining the action threshold using the double tangent method: Tangents are drawn at the starting point (minimum application amount of humectant 0.05%) and the ending point (maximum application amount of humectant 4.00%) of the second relationship curve. The application amount of humectant corresponding to the intersection of the two tangents is the action threshold of propylene glycol under standard environmental conditions, and the measured value is 1.14%.

[0062] Example 2 This embodiment provides the determination of the action threshold of glycerin as a humectant under high temperature and low humidity conditions.

[0063] (1) Application of humectant and sample preparation: Glycerin was uniformly applied to the formulated tobacco shreds at different concentration gradients. Based on the weight of the tobacco shreds, the amount of glycerin applied was 0.05 wt%, 0.50 wt%, 1.00 wt%, 2.00 wt%, 3.00 wt%, 4.00 wt%, and 5.00 wt%.

[0064] (2) Determination of equilibrium moisture content: The tobacco shreds with different concentration gradients of glycerol were placed under high temperature and low humidity conditions (temperature 45℃, relative humidity 20%) for 48 hours to equilibrate. The equilibrium moisture content of each sample was determined by oven drying method (refer to YC / T 31-1996).

[0065] (3) Fitting the first relationship curve: A scatter plot was drawn with the amount of moisturizing agent applied as the independent variable x and the equilibrium moisture content as the dependent variable y. Logarithmic function, exponential saturation function, power function, and Michaelis-Menten equation were used for fitting. The fitting results are shown in Table 2. Among them, the Michaelis-Menten equation had the highest correlation coefficient (R²=0.9973) and the smallest chi-square (χ²=0.00177). Therefore, the Michaelis-Menten equation was chosen as the fitting equation for the first relationship curve, as shown in Table 2. Figure 3 As shown.

[0066] Table 2. Correlation coefficients and chi-square values ​​for different fitting equations

[0067] (4) Obtain the second relationship curve by taking the differential: Take the first derivative of the above Michaelis equation to obtain the relationship curve between the rate of change of equilibrium moisture content and the amount of moisturizing agent applied (the second relationship curve), as shown in the figure. Figure 4 As shown.

[0068] (5) Determining the action threshold using the double tangent method: Tangents are drawn at the starting point (minimum application amount of humectant 0.05%) and the ending point (maximum application amount of humectant 5.00%) of the second relationship curve. The application amount of humectant corresponding to the intersection of the two tangents is the action threshold of glycerin under high temperature and low humidity conditions. The measured value is 1.08%.

[0069] Experimental Example 1 This test example is used to verify whether the action threshold determined by the method of the present invention (taking the propylene glycol threshold of 1.14% in Example 1 as an example) truly corresponds to the optimal balance between moisturizing effect and economy.

[0070] 1. Sample preparation Propylene glycol was uniformly applied to the same batch of formulated tobacco at the following dosages: 0.5 × threshold (0.57%), 1 × threshold (1.14%), 1.5 × threshold (1.71%), and 2 × threshold (2.28%). A blank control group without humectant was also included. All groups of tobacco were equilibrated for 48 hours under standard environmental conditions (22°C, 60% RH).

[0071] 2. Testing Methods (1) Determination of breakage resistance: Take 15g of balanced tobacco shreds and crush them in a plant shredder for 3s with a power of 250W and a rotation speed of 500r / min. After crushing, pass the shredded material through a 16-mesh sieve. The breakage resistance is expressed as the percentage of the mass of the material on the sieve to the mass of the test sample. The higher the breakage resistance, the better the processing resistance.

[0072] (2) Determination of the water loss rate constant k: After equilibrium, each group of tobacco shreds was placed in a 50℃ constant temperature oven, and samples were taken at 0h, 1h, 2h, 4h, 8h, 12h, and 24h to determine the moisture content at each time point. The Page drying model was used for fitting: Mr = exp(-k·t n ), where Mr is the moisture ratio, t is time, k is the water loss rate constant, and n is the shape parameter of the drying model (dimensionless, determined by the fitting process). The smaller the value of k, the stronger the water retention capacity of the tobacco.

[0073] (3) Sensory quality evaluation: A 7-member evaluation team will be formed to evaluate cigarettes according to the sensory quality evaluation standard (refer to YC / T 415-2011). The evaluation will score ten indicators: aroma quality, aroma quantity, permeability, impurities, smoke concentration, fineness, smoothness, irritation, dryness, and strength. Each indicator will be scored out of 10 points, for a total of 100 points.

[0074] (4) Sensory gain per unit threshold multiple: Arrange each sample in order of threshold multiple (the ratio of the actual amount of moisturizer applied to the effective threshold) from low to high, and then calculate the sensory gain per unit threshold multiple between adjacent samples. Sensory gain per unit threshold multiple = (sensory score of the next sample - sensory score of the previous sample) / (threshold multiple of the next sample - threshold multiple of the previous sample).

[0075] 3. Test Results The test results are shown in Table 3.

[0076] Table 3. Breakage resistance, water loss rate, and sensory quality at different addition levels.

[0077] As shown in Table 3, the fracture resistance increases with the increase of the amount of humectant applied, but the increase is most significant at 1×th threshold (from 67.5 at 0.5×th threshold to 71.5, an increase of 4.0 percentage points). After that, the increase in fracture resistance decreases significantly with further increases in humectant (1.5×th threshold is only 1.6 percentage points higher than 1×th threshold).

[0078] The water loss rate constant k decreases with increasing application of the wetting agent, indicating enhanced water retention capacity. The decrease in k value is greatest at 1×th threshold (from 0.346 at 0.5×th threshold to 0.324, a decrease of 0.022), after which the decrease tends to level off.

[0079] The sensory quality score reached almost its highest point (87.7 points) at the 1× threshold, which was characterized by increased aroma permeability, smooth and delicate smoke, and reduced dryness. After exceeding the 1× threshold, the score no longer increased and even decreased (87.5 points at the 2× threshold), which was characterized by decreased smoke purity, cloudy smoke, and reduced permeability.

[0080] The increase in sensory score per unit threshold cost was highest at 1× threshold (2.4), significantly higher than at 0.5× threshold (1.8), but dropped sharply or even turned negative at 1.5× threshold and 2× threshold. This indicates that beyond 1× threshold, further increases in humectant not only become less economical, but may also deteriorate sensory quality.

[0081] The above results fully demonstrate that the effective threshold (1.14%) determined by the method in Example 1 of this invention is indeed the optimal balance point between moisture retention and economy. At this addition amount, the processing resistance, water retention capacity and sensory quality of the tobacco shreds all reach a better level, and the unit cost benefit is the best.

[0082] Experimental Example 2 This experimental example is used to verify the versatility of the method described in this application for different types of humectants and different environmental conditions.

[0083] Three humectants were selected: glycerin, propylene glycol, and sorbitol, as well as a mixture of glycerin and propylene glycol (mass ratio 4:6). Threshold determinations were performed under different environmental conditions: standard environment (22℃, 60%RH), low temperature and low humidity (10℃, 20%RH), and high temperature and low humidity (45℃, 20%RH). The action threshold of each humectant was determined according to the method in Example 1 under each environmental condition. Each sample was repeated six times, and the coefficient of variation of the action threshold was calculated. The test results are shown in Table 4. The smaller the coefficient of variation, the more reliable the threshold determination method of the technical solution.

[0084] Table 4. Coefficients of variation of the action thresholds of different humectants under different environmental conditions

[0085] It is evident that the coefficients of variation of the action thresholds of each humectant under different environments are all below 6%, indicating that the method has good stability.

[0086] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for determining the action threshold of tobacco humectants based on the double-tangent method, characterized in that, Includes the following steps: The equilibrium moisture content of tobacco shreds treated with different concentration gradient humectants was determined under specific storage conditions. Using the amount of humectant applied as the independent variable and the equilibrium moisture content as the dependent variable, the first relationship curve was obtained by fitting the data. Differentiating the first relationship curve yields the relationship curve between the rate of change of equilibrium moisture content and the amount of moisturizing agent applied, which is denoted as the second relationship curve. Tangents are drawn at the starting and ending points of the second relationship curve, and the amount of moisturizing agent applied at the intersection of the two tangents is determined as the threshold of moisturizing agent action.

2. The determination method as described in claim 1, characterized in that, The humectant includes at least one of propylene glycol, glycerin, and sorbitol.

3. The determination method as described in claim 1, characterized in that, The specific storage conditions are a constant temperature and relative humidity environment; the equilibrium moisture content is measured under the specific storage conditions for more than 45 hours.

4. The determination method as described in claim 1, characterized in that, The fitting function for the first relationship curve is selected from logarithmic functions, exponential saturation functions, power functions, or Michaelis-Menten equations.

5. The determination method as described in claim 4, characterized in that, By comparing the correlation coefficients (R²) of different fitting functions 2 ) and chi-square value (χ) 2 To select the optimal fitting function.

6. The determination method as described in claim 1, characterized in that, Based on the quality of the tobacco shreds, the amount of the humectant applied is 0~5wt%.

7. The determination method as described in claim 1, characterized in that, The starting and ending points of the second relationship curve are the minimum and maximum amounts of moisturizer applied, respectively.

8. A system for determining the action threshold of tobacco humectants based on the double-tangent method, characterized in that, include: The equilibrium moisture content measurement module is used to measure the equilibrium moisture content of tobacco shreds with different concentration gradient humectants under specific storage conditions. The curve fitting module is used to fit the first relationship curve with the amount of humectant applied as the independent variable and the equilibrium moisture content as the dependent variable. The differentiation module is used to differentiate the first relationship curve to obtain the second relationship curve; The threshold calculation module is used to draw tangents at the starting and ending points of the second relationship curve, and determine the amount of moisturizer applied at the intersection of the two tangents as the moisturizer action threshold.

9. An electronic device, characterized in that, It includes a processor and a memory, the memory storing a computer program, and the processor executing the computer program to implement the steps of the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, It stores a computer program thereon, which, when executed by a processor, implements the steps of the method described in any one of claims 1 to 7.

Images