A tobacco leaf slitting method based on lignin phenol monomer characteristic difference and application thereof

Abstract

The present application relates to a tobacco cutting method based on the characteristic difference of lignin phenol monomers and its application, the cutting method comprises the following steps: (1) dividing the tobacco into several continuous tobacco sections; (2) determining the content of lignin phenol monomers in each tobacco section of step (1); (3) taking the content of lignin phenol monomers in each tobacco section of step (2) as the classification index, the several continuous tobacco sections are divided into several continuous categories, wherein the lignin phenol monomer difference of the tobacco sections in each category is minimized, and the lignin phenol monomer difference of the tobacco sections between each category is maximized. The tobacco cutting method provided by the present application realizes fine cutting based on aroma potential and combustion safety under the premise of maintaining the physical continuity of tobacco, thereby having the beneficial technical effects of significantly improving the raw material utilization value, the quality stability of cigarette products and the smoking safety.

Description

Technical Field

[0001] This invention relates to the field of tobacco processing technology, and in particular to a method for cutting tobacco leaves based on the differences in the characteristics of lignin monomers and its application. Background Technology

[0002] High-quality tobacco leaves are the foundation for the high-quality development of Chinese-style cigarettes. With the continuous optimization and upgrading of cigarette product structure, the structural contradiction between the supply and demand of high-quality tobacco leaves is becoming increasingly prominent. Current production methods mostly employ whole-leaf processing, failing to fully consider the quality differences between different locations of the same tobacco leaf, thus reducing the use value of the tobacco leaf.

[0003] Studies have shown that, under the combined regulation of genetic factors, light conditions, and the rate of water migration during the baking process, there are significant differences in the conventional chemical composition and physical processing properties of different regions of the same tobacco leaf (from leaf tip to leaf base).

[0004] CN119715450A discloses a method for cutting tobacco leaves based on thickness distribution patterns. The method uses a thickness gauge to detect the thickness of different sections of the initially cured tobacco leaves, analyzes the changing trends of the thickness in different sections, and then uses Fisher's optimal segmentation method to optimally segment the tobacco leaves based on the thickness variations. Finally, sensory evaluation is used to verify the rationality of the tobacco leaf segmentation method based on Fisher's optimal segmentation method, providing a reference for the differentiated threshing and re-curing processing and scientific utilization of tobacco leaves after segmentation.

[0005] CN103120361A discloses a method for cutting tobacco leaves based on the distribution law of chemical components. After cutting the tobacco leaves, the chemical component information of different cutting parts is measured, and the chemical component information of the tobacco leaves and the cutting parts are statistically analyzed. Then, the number of times the tobacco leaves are cut and the cutting position are determined according to the distribution law of the chemical components of the tobacco leaves.

[0006] The existing tobacco leaf cutting methods cannot accurately reflect the inherent differences in the sensory quality of tobacco leaves in different sections. Therefore, it is necessary to provide a more scientific, objective and operable tobacco leaf cutting method. Summary of the Invention

[0007] To address the aforementioned technical problems, this invention provides a method for tobacco leaf slicing based on the differences in lignin phenol monomer characteristics and its application. The tobacco leaf slicing method provided by this invention achieves refined slicing based on aroma potential and combustion safety while maintaining the physical continuity of the tobacco leaves, thereby significantly improving the utilization value of raw materials, the stability of cigarette product quality, and smoking safety.

[0008] To achieve this objective, the present invention adopts the following technical solution: In a first aspect, the present invention provides a method for cutting tobacco leaves based on the differences in the characteristics of lignin monomers, the method comprising the following steps: (1) Divide the tobacco leaves into several continuous tobacco leaf segments; (2) Determine the content of lignin monomers in each tobacco leaf segment in step (1); (3) Using the content of lignin monomers in each tobacco leaf segment in step (2) as the classification index, the several consecutive tobacco leaf segments are divided into several consecutive categories, wherein the difference in lignin monomers in tobacco leaf segments within each category is minimized, and the difference in lignin monomers in tobacco leaf segments between each category is maximized.

[0009] Lignin, a phenolic macromolecule polymer second only to cellulose in plant content, is composed of three basic units: p-hydroxyphenyl (H), guaiacol (G), and syringyl (S). It has a dual impact on the sensory quality and smoking safety of cigarettes: during the alcohol degradation process, it can produce small molecule aroma substances such as benzaldehyde and phenylacetaldehyde, which improve the smoking quality; however, it also produces harmful components such as phenols and polycyclic aromatic hydrocarbons during combustion and pyrolysis.

[0010] The absolute content of lignin is difficult to quantify directly. In practice, it is usually characterized indirectly by extracting its phenolic monomers (including eight marker monomers in three major categories: cinnamyl C, eugenol S, and vanillyl V). The content and ratio of these monomers can not only indicate the characteristics of plant-derived carbon, but also effectively reflect the degree and state of lignin degradation.

[0011] This invention determines the content of lignin monomers in different segments of tobacco leaves and uses this as a classification index to segment the leaves. This achieves refined segmentation based on aroma potential and combustion safety while maintaining the physical continuity of the tobacco leaves. This results in significantly improved raw material utilization, cigarette product quality stability, and smoking safety. Furthermore, the tobacco leaf segmentation method provided by this invention corresponds to the sensory quality evaluation results of the tobacco leaves, demonstrating the accuracy, scientific validity, and objectivity of the method.

[0012] Preferably, step (1) further includes removing the leaf base portion of the tobacco leaves before the splitting.

[0013] Preferably, the segmentation method in step (1) is: dividing the tobacco leaf into several continuous tobacco leaf segments along the vertical direction of the main vein.

[0014] Preferably, the number of tobacco leaf segments in step (1) is 3 or more (e.g., 3, 6, 8, 10, 12, 14, 16, 20, 25, etc.), more preferably 8 or more, and even more preferably 8-15.

[0015] Preferably, the lignin monomer in step (2) includes any one or a combination of at least two of cinnamyl (C) phenol monomer, eugenyl (S) phenol monomer, or vanillyl (V) phenol monomer.

[0016] Preferably, the cinnamylphenol monomer comprises ferulic acid and / or p-coumaric acid.

[0017] Preferably, the eugenol monomer includes any one or a combination of at least two of eugenol, eugenone, or eugenolic acid.

[0018] Preferably, the vanillylphenol monomer includes any one or a combination of at least two of vanillin, vanillyl ethyl ketone, or vanillic acid.

[0019] Preferably, the method for testing the content of lignin monomers in step (2) includes gas chromatography, gas chromatography-mass spectrometry or liquid chromatography-tandem mass spectrometry.

[0020] Preferably, step (2) further includes pretreatment of each tobacco leaf segment by crushing, extraction and silane derivatization before the determination.

[0021] Preferably, the segmentation in step (3) uses Fisher's optimal segmentation method.

[0022] Preferably, in the Fisher optimal segmentation method, the minimum objective function value under different numbers of categories is calculated, the number of categories that makes the change of the minimum objective function value show an obvious inflection point is selected as the optimal number of categories, and each tobacco leaf segment is classified according to the optimal number of categories.

[0023] Preferably, step (3) further includes sensory quality evaluation of tobacco leaf segments of various categories, and verification of the effect of tobacco leaf cutting based on the sensory quality evaluation results.

[0024] Preferably, the sensory quality evaluation indicators include any one or a combination of at least two of the following: aroma quality, aroma quantity, off-odors, concentration, strength, irritation, or aftertaste.

[0025] Secondly, the present invention provides an application of the tobacco leaf cutting method based on the differences in lignin monomer characteristics described in the first aspect in tobacco leaf classification, screening or quality testing.

[0026] Thirdly, the present invention provides a tobacco leaf slicing product, which is prepared according to the tobacco leaf slicing method based on the differences in the characteristics of lignin phenol monomers described in the first aspect.

[0027] Compared with the prior art, the present invention has at least the following beneficial effects: 1. Achieved innovation and precision in the basis for slicing: For the first time, this invention uses the characteristics of lignin phenol monomers (preferably the content and ratio of 8 specific monomers) as the core slicing index, breaking through the limitation of relying solely on conventional chemical components; this index can more fundamentally reflect the inherent differences of tobacco leaves in terms of aroma potential (derived from degradation products) and combustion safety (derived from pyrolysis behavior), providing a new and more precise scientific basis for achieving refined and functional slicing of tobacco leaves.

[0028] 2. This invention provides a scientific, objective, and operable basis for segmentation decisions: It uses lignin phenol monomers (such as ferulic acid, p-coumaric acid, eugenol, eugenone, eugenol, etc.) as quantitative indicators and determines the optimal number of classifications using R language statistical tools (such as through the inflection point of the e[p(n,k)]-k ​​curve), making the selection of segmentation schemes based on evidence and scientifically objective. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of tobacco leaf cutting in Example 1.

[0030] Figure 2 The graph shows the correlation between e[p(n,k)] and k (horizontal axis) of C3F tobacco leaves in Example 1.

[0031] Figure 3 The graph shows the correlation between e[p(n,k)] and k (horizontal axis) of C3F tobacco leaves in Comparative Example 1. Detailed Implementation

[0032] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments. However, the following examples are merely simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention is determined by the claims.

[0033] The tobacco leaves used in the following examples are C3F grade primary flue-cured tobacco leaves of the Yunyan 87 variety collected in Pu'er, Yunnan.

[0034] Example 1 This embodiment provides a method for tobacco leaf cutting based on the differences in the characteristics of lignin phenol monomers, including the following steps: 1. Slicing tobacco leaves Take a number of uniformly sized C3F grade flue-cured tobacco leaves from the same batch. Using a stainless steel knife, cut off and discard the base of each leaf (5cm from the end of the petiole). Divide the remaining main body of the tobacco leaf precisely into 10 equal sections along the vertical direction of the midrib, numbering them sequentially from leaf tip to leaf base as Q1, Q2, ..., Q10 (see...). Figure 1 ).

[0035] 2. Determination of lignin monomers Non-destructive testing was conducted on the tobacco leaf samples from the above 10 cut sections (Q1-Q10) to determine the content of eight lignin monomers (unit: µg / g), including vanillin, vanillic acid, eugenone, vanillin ethyl ketone, eugenol, eugenol, ferulic acid, and p-coumaric acid.

[0036] The detection method is as follows: Take 0.05 g of tobacco dust sample and add 1 mL of extraction buffer (dichloromethane:acetonitrile = 2:1). Sonicate at 25℃ for 60 min, then centrifuge at 12000 rpm and 32℃ for 10 min. Transfer 150 μL of supernatant to a centrifuge tube, then add 80 μL of methoxyl reagent (120 mg methoxyamine hydrochloride added to 6 mL pyridine). React at 37℃ in the dark for 1 h. Add 80 μL of bis(trimethylsilyl)trifluoroacetamide and react in a metal bath at 60℃ for 40 min. Centrifuge again at 12000 rpm and 32℃ for 10 min. Finally, transfer the supernatant to a GC-MS sample vial for detection.

[0037] GC-MS analysis conditions: Column: DB-5MS (60m×250μm×0.25μm); Injector temperature: 270℃; Carrier gas: high-purity helium; Control mode: linear; Column flow rate: 1mL / min; Split ratio: splitless; Temperature program: Initial temperature 60℃, hold for 0.5min; Increase to 200℃ at a rate of 30℃ / min; After 3min, increase to 220℃ at a rate of 5℃ / min, hold for 2min; Increase to 210℃ at a rate of 0.5℃ / min; After 1min, increase to 280℃ at a rate of 5℃ / min, hold for 5min; Solvent delay: 9min; Electron impact ion source (EI): Electron voltage 70eV; Ion source temperature: 230℃; Interface temperature: 280℃; Acquisition method: SIM; Quantification: External standard method.

[0038] Each sample was measured three times, and the average value was taken. The results of the determination of lignin monomer content in each cut section and grade of tobacco leaves are shown in Table 1.

[0039] Table 1 The results showed that the lignin monomers in tobacco leaves exhibited a regular and gradient change from Q1 to Q10: vanillin and vanillic acid generally decreased, while the contents of eugenol, vanillin ethyl ketone, eugenol, eugenic acid, and p-coumaric acid generally increased, and ferulic acid showed a trend of first increasing and then decreasing. This demonstrates the scientific necessity of cutting and utilizing tobacco leaves separately from each other.

[0040] 3. Fisher's optimal segmentation method for classification Using R language statistical tools, eight lignin phenol monomers (vanillin, vanillic acid, eugenone, vanillyl ethyl ketone, eugenol, eugenol, eugenol, p-coumaric acid, and ferulic acid) in the Q1-Q10 range were used as analysis indicators. First, the data were standardized to eliminate the influence of dimensions. Then, Fisher's optimal segmentation method was used to classify ordered samples and calculate the minimum objective function value e[p(n,k)] for different numbers of categories (k=2 to 9). The results are shown in Table 2.

[0041] Table 2 Plot the curve of e[p(n,k)] as a function of the value of k (see...) Figure 2 As can be seen, the curve shows a clear inflection point at k=3, indicating that when divided into 3 categories, the differences within each category are small, while the differences between categories are large, resulting in the best classification effect. Furthermore, the partitions are continuous (Q1-Q4, Q5-Q8, Q9-Q10), which facilitates production operations.

[0042] Therefore, the optimal classification scheme is determined to be: upper segment (Q1-Q4), middle segment (Q5-Q8), and lower segment (Q9-Q10). Analysis of variance (F-test) showed significant differences among the three segments in all eight chemical indicators. F Value > F α , p <0.05), proving that the classification result is valid.

[0043] Therefore, based on Fisher's optimal segmentation method and longitudinal distribution law analysis of tobacco lignin monomers, the number of times the C3F first-cured tobacco leaves of Yunyan 87 were cut into 3 segments: leaf tip: leaf middle: leaf base = 40%: 40%: 20%.

[0044] 4. Sensory quality evaluation To verify the rationality of dividing tobacco leaves using the Fisher optimal segmentation method based on the lignin monomer content, C3F grade tobacco leaves of Yunyan 87 were divided strictly according to the segmentation ratio requirements, based on the above analysis results. Seven sensory quality professionals evaluated the different segmented areas and whole leaf samples using a 9-point system, considering seven indicators: aroma quality, aroma quantity, off-flavors, concentration, strength, irritation, and aftertaste. The total score was calculated as follows: Total Score = (Aroma Quality + Aroma Quantity) × 2.4 + (Concentration + Aftertaste) × 1.6 + Off-flavors + Strength + Irritation. The results are shown in Table 3.

[0045] Table 3 Note: Different lowercase letters in the superscript of data in the same column indicate significant differences. p <0.05).

[0046] The results showed that the total score among the samples was as follows: middle section (68.23) > upper section (67.21) > whole leaf (66.66) > lower section (66.12), and there was a significant difference in the total score among the three sections. In addition, the quality of the upper and middle sections was improved compared with the whole leaf.

[0047] Comparative Example 1 This comparative example provides a method for cutting tobacco leaves based on differences in conventional chemical composition characteristics, including the following steps: 1. Slicing tobacco leaves (refer to Example 1) 2. Determination of conventional chemical components The conventional chemical composition of each cut tobacco leaf of Yunyan 87 C3F grade was determined based on near-infrared spectroscopy, and the results are shown in 4.

[0048] Table 4 The results showed that the contents of total alkaloids, reducing sugars, and total sugars decreased with location; the contents of total nitrogen (Q1 and Q10) were relatively high, while those of Q2-Q9 were relatively stable with small fluctuations; the contents of potassium showed a trend of first decreasing and then increasing; and the contents of chlorine showed a significant increasing trend.

[0049] 3. Fisher's optimal segmentation method for classification Using R language statistical tools, six common chemical components in the Q1-Q10 range were used as analytical indicators. First, the data were standardized to eliminate the influence of dimensions. Then, Fisher's optimal segmentation method was used to classify the ordered samples and calculate the minimum objective function value e[p(n,k)] for different numbers of categories (k=2 to 9). The results are shown in Table 5.

[0050] Table 5 Plot the curve of e[p(n,k)] as a function of the value of k (see...) Figure 3 As can be seen, the curve shows a clear inflection point at k=3, indicating that when divided into 3 categories, the differences within each category are small, while the differences between categories are large, resulting in the best classification effect. Furthermore, the partitions are continuous (Q1-Q7, Q8-Q9, Q10), which facilitates production operations.

[0051] Therefore, the optimal classification scheme is determined to be: upper segment (Q1-Q7), middle segment (Q8-Q9), and lower segment (Q10). Analysis of variance (F-test) showed significant differences among the three segments in all six chemical indicators. F Value > F α , p <0.05), proving that the classification result is valid.

[0052] Therefore, based on the systematic cluster analysis of the conventional chemical components of tobacco leaves and the longitudinal distribution pattern, the number of times the C3F first-cured tobacco leaves of the Yunyan 87 variety were cut was divided into 3 segments: leaf tip: leaf middle: leaf base = 70%: 20%: 10%.

[0053] 4. Sensory quality evaluation The sensory quality of the slit tobacco leaves was evaluated according to the method in Example 1, and the results are shown in Table 6.

[0054] Table 6 Note: Different lowercase letters in the superscript of data in the same column indicate significant differences. p <0.05).

[0055] As shown in Table 6, the upper section of the comparative example has the highest total score, but the difference from the total score of the whole leaf is not significant. In addition, compared with the total sensory quality scores of each section of the cigarette in the examples, the scores of each section of tobacco leaf B are lower. This indicates that the segmentation of tobacco leaf B into a class obtained by the method of the examples is more reasonable, and the quality improvement effect of each section is significant.

[0056] Example 2 This embodiment provides a tobacco leaf cutting method based on the differences in the characteristics of lignin phenol monomers. The only difference between this method and Example 1 is that in step 3, only vanillin, vanillic acid, eugenone, vanillyl ethyl ketone, eugenol, and eugenol are used as analytical indicators. The optimal cutting scheme results are the same as in Example 1, and the effect is the same.

[0057] Example 3 This embodiment provides a tobacco leaf segmentation method based on the differences in lignin monomer characteristics. The only difference from Embodiment 1 is that in step 3, only ferulic acid and p-coumaric acid are used as analytical indicators to determine the optimal classification scheme as: upper segment (Q1-Q4), middle segment (Q5-Q7), and lower segment (Q8-Q10). Analysis of variance (F-test) showed significant differences in both chemical indicators among the three segments. F Value > F α , p <0.05), proving that the classification result is valid.

[0058] Therefore, based on Fisher's optimal segmentation method and longitudinal distribution law analysis of tobacco lignin monomers, the number of times the C3F first-cured tobacco leaves of Yunyan 87 were cut into 3 segments: leaf tip: leaf middle: leaf base = 40%: 30%: 30%.

[0059] The sensory quality of samples from different cut sections and whole leaves was evaluated according to Example 1, and the results are shown in Table 7.

[0060] Table 7 Note: Different lowercase letters in the superscript of data in the same column indicate significant differences. p <0.05).

[0061] The results showed that the total score among the samples was as follows: upper section (67.21) > middle section (66.95) > whole leaf (66.66) > lower section (66.50), with significant differences in total scores among the three sections. Furthermore, compared to the whole leaf, the upper and middle sections showed improved quality. Compared to the comparative example, the upper, middle, and lower sections in Example 3 all had higher total scores, demonstrating a significant improvement.

[0062] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A method for cutting tobacco leaves based on the differences in the characteristics of lignin monomers, characterized in that, The slicing method includes the following steps: (1) Divide the tobacco leaves into several continuous tobacco leaf segments; (2) Determine the content of lignin monomers in each tobacco leaf segment in step (1); (3) Using the content of lignin monomers in each tobacco leaf segment in step (2) as the classification index, the several consecutive tobacco leaf segments are divided into several consecutive categories, wherein the difference in lignin monomers in tobacco leaf segments within each category is minimized, and the difference in lignin monomers in tobacco leaf segments between each category is maximized.

2. The tobacco leaf cutting method according to claim 1, characterized in that, Step (1) before the splitting process also includes removing the leaf base portion of the tobacco leaves; Preferably, the segmentation method in step (1) is: dividing the tobacco leaf into several continuous tobacco leaf segments along the vertical direction of the main vein; Preferably, the number of tobacco leaf segments in step (1) is 3 or more, more preferably 8 or more, and even more preferably 8-15.

3. The tobacco leaf cutting method according to claim 1 or 2, characterized in that, The lignin monomers in step (2) include any one or a combination of at least two of cinnamylphenol monomers, eugenol monomers, or vanillylphenol monomers.

4. The tobacco leaf cutting method according to claim 3, characterized in that, The cinnamylphenol monomer includes ferulic acid and / or p-coumaric acid; Preferably, the eugenol monomer comprises any one or a combination of at least two of eugenol, eugenone, or eugenol acid; Preferably, the vanillylphenol monomer includes any one or a combination of at least two of vanillin, vanillyl ethyl ketone, or vanillic acid.

5. The tobacco leaf cutting method according to any one of claims 1-4, characterized in that, The test method for the content of lignin phenol monomers in step (2) includes gas chromatography, gas chromatography-mass spectrometry or liquid chromatography-tandem mass spectrometry; Preferably, step (2) further includes pretreatment of each tobacco leaf segment by crushing, extraction and silane derivatization before the determination.

6. The tobacco leaf cutting method according to any one of claims 1-5, characterized in that, The segmentation in step (3) adopts Fisher's optimal segmentation method; Preferably, in the Fisher optimal segmentation method, the minimum objective function value under different numbers of categories is calculated, the number of categories that makes the change of the minimum objective function value show an obvious inflection point is selected as the optimal number of categories, and each tobacco leaf segment is classified according to the optimal number of categories.

7. The tobacco leaf cutting method according to any one of claims 1-6, characterized in that, Step (3) also includes sensory quality evaluation of tobacco leaf segments of various categories, and verification of the effect of tobacco leaf cutting based on the sensory quality evaluation results.

8. The tobacco leaf cutting method according to claim 7, characterized in that, The sensory quality evaluation indicators include any one or a combination of at least two of the following: aroma quality, aroma quantity, off-flavors, concentration, strength, irritation, or aftertaste.

9. The application of a tobacco leaf cutting method based on the difference in lignin monomer characteristics according to any one of claims 1-8 in tobacco leaf classification, screening or quality inspection.

10. A tobacco leaf slicing product, characterized in that, The tobacco leaf slicing product is prepared by the tobacco leaf slicing method based on the differences in lignin monomer characteristics according to any one of claims 1-8.

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