A method to improve the availability of Burley tobacco leaves

Abstract

This invention provides a method for improving the usability of Burley tobacco leaves, relating to the field of tobacco processing technology. The method involves first pretreating the Burley tobacco leaves with a mixed solution containing sugar, salt, and acetic acid. After soaking, the leaves are treated with cold air, followed by soaking in a mixed solution containing sugar and a compound liquid. After soaking, the moisture content of the tobacco leaves is adjusted to complete the process. The treated Burley tobacco has a more harmonious chemical composition and imparts a flue-cured tobacco-like aroma, significantly reducing characteristic odors, lowering strength, and noticeably improving aftertaste. This enhances the sensory quality of the Burley tobacco and greatly improves its applicability in cigarette formulations.

Description

Technical Field

[0001] This invention relates to the field of tobacco processing technology, and in particular to a method for improving the usability of Burley tobacco. Background Technology

[0002] Burley tobacco, belonging to the safflower tobacco variety, is an important raw material for cigarettes, playing a significant role in blended cigarettes. It can also be used in cigars, pipe tobacco, and chewing tobacco. Burley tobacco has a relatively thick midrib, high moisture content, thin and light leaves, a loose but not coarse tissue structure, high elasticity, high filling value, and good absorption of flavorings. Its nicotine and total nitrogen content are higher than flue-cured tobacco. However, Burley tobacco generally has a low sugar content, a high nicotine content, a strong smoke, and a less pronounced and insufficient aroma. Chinese-style cigarettes are mainly made with flue-cured tobacco. A suitable amount of Burley tobacco is generally added to flue-cured cigarette formulas to enrich and enhance the aroma, increase strength, and reduce the release of harmful substances such as tar. However, because the properties of Burley tobacco itself can alter the style characteristics of flue-cured cigarettes, the prominent Burley tobacco aroma can disrupt the harmony of the original cigarette aroma, greatly limiting the application of Burley tobacco. Therefore, how to weaken or mask and harmonize the aroma of Burley tobacco, reduce its strength, improve its aftertaste, and enhance the usability of Burley tobacco raw materials in Chinese cigarettes has very important practical application value.

[0003] Patent CN103653232A discloses a reconstituted tobacco production process that masks the characteristic aroma of Burley tobacco, including the following steps: adding sugar and acidic reactants during the extraction of Burley tobacco raw materials, followed by solid-liquid separation and pulping, then adding wood fiber and auxiliary materials, and preparing reconstituted tobacco leaf base sheets by sheet forming; after the Burley tobacco extract is concentrated, adding some flue-cured tobacco aroma components, and coating it onto the reconstituted tobacco leaf base sheets to obtain reconstituted tobacco based on Burley tobacco as raw material components.

[0004] For example, patent CN109527635A discloses a process method for improving the quality of Burley tobacco and its application. In the Burley tobacco production process, during the loosening, rehydration, heating and humidification, a compound biological agent (Saccharomyces cerevisiae and asparaginase) solution is evenly sprayed. During the premixed storage, hydrolysis and fermentation are carried out. During the feeding, temperature and humidity are increased again, a weakly alkaline asparaginase and amino acid mixed solution is sprayed again. In the leaf storage process, hydrolysis, fermentation and Maillard reaction are carried out again. After cutting into shreds, a high-temperature Maillard reaction is carried out in the drying process to obtain Burley tobacco shreds.

[0005] Currently, there are many methods for masking the distinctive aroma of Burley tobacco, such as high-temperature roasting, adding sugar during processing, soaking in aqueous solutions or weak acid / alkaline solutions, or treatment with compound biological agents. While these methods have some effect, the effectiveness of a single treatment method is limited, and the characteristic aroma, strength, aftertaste, and stability of aroma compounds in the treated Burley tobacco still have shortcomings, thus its applicability needs to be improved. Therefore, it is necessary to provide a method to improve the usability of Burley tobacco leaves. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of existing technologies by providing a method to improve the usability of Burley tobacco leaves. The chemical composition of the treated Burley tobacco is more harmonious, and it can impart a flue-cured tobacco-like aroma to the Burley tobacco. The characteristic aroma is significantly reduced, the strength is lowered, and the aftertaste is significantly improved, thereby improving the sensory quality of Burley tobacco leaves and greatly enhancing their applicability in cigarette formulations.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] A method for improving the usability of burley tobacco leaves includes the following steps:

[0009] S1. Dissolve ethanol and sodium tartrate in water to obtain a pretreatment solution;

[0010] S2. Place the burley tobacco leaves into the pretreatment solution for pretreatment;

[0011] S3. After pretreatment, remove the product and treat it with cold air.

[0012] S4. Dissolve the sugar in water, add it to the compound solution and mix well to obtain the soaking solution;

[0013] S5. Soak the burley tobacco leaves in the soaking solution.

[0014] S6. After soaking, remove the Burley tobacco leaves, dehydrate them and adjust the moisture content to 16-18%, thus completing the treatment.

[0015] The pretreatment solution contains ethanol, sodium tartrate, and water;

[0016] The compound liquid contains amino acids, organic acids, fragrance substances, plant extracts, and solvents.

[0017] Further, in steps S1 and S4, the sugar is at least one of fructose, lactose, glucose, maltose, invert sugar, sucrose, honey, and fruit syrup.

[0018] Furthermore, in step S1, the water is any one of purified water, distilled water, and deionized water.

[0019] Further, in step S1, the pretreatment solution, by mass percentage, comprises: 50-75% ethanol, 3-8% sodium tartrate, and the remainder water. Preferably, the pretreatment solution, by mass percentage, comprises: 60-70% ethanol, 4-5% sodium tartrate, and the remainder water.

[0020] Further, in step S2, the solid-liquid ratio of the burley tobacco leaves to the pretreatment liquid is 1:(8-20)g / mL. Preferably, in step S2, the solid-liquid ratio of the burley tobacco leaves to the pretreatment liquid is 1:(10-15)g / mL.

[0021] Further, in step S2, the pretreatment conditions are: temperature 55-65℃, time 10-30 min. Preferably, in step S2, the pretreatment conditions are: temperature 60-65℃, time 20-30 min.

[0022] Furthermore, in step S3, the conditions for the cold air treatment are: cold air temperature 10-15℃, cold air speed 8-10m / s, and time 0.5-2h.

[0023] Further, in step S4, the amount of the sugar is 1-4% of the water mass, and the amount of the composite solution is 1-7% of the water mass. Preferably, the amount of the sugar is 2-3% of the water mass, and the amount of the composite solution is 4-5% of the water mass.

[0024] Further, in step S4, the organic acid in the composite liquid is at least one of citric acid, sodium tartrate, malic acid, and lactic acid, and the organic acid is food grade; the flavoring substance includes 2-methylpyrazine, 2,3-dimethylpyrazine, fennel oil, and anise oil; the plant extract includes hop extract, plum extract, and cocoa extract; and the solvent is propylene glycol.

[0025] Preferably, the amino acids comprise glutamic acid, glycine, alanine, and aspartic acid in a mass ratio of 1:(0.5-2):(0.5-1.5):(1-3). More preferably, the amino acids comprise glutamic acid, glycine, alanine, and aspartic acid in a mass ratio of 1:(1-1.5):(1-1.5):(1-2).

[0026] Preferably, the flavoring substance comprises 2-methylpyrazine, 2,3-dimethylpyrazine, fennel oil, and anise oil in a mass ratio of (0.2-1):(0.2-1):(1-3):(0.5-2). More preferably, the flavoring substance comprises 2-methylpyrazine, 2,3-dimethylpyrazine, fennel oil, and anise oil in a mass ratio of (0.5-0.8):(0.5-0.7):(2-2.5):(1-1.5).

[0027] Preferably, the plant extract is a mixture of hop extract, plum extract, and cocoa extract in a mass ratio of (8-15):(0.5-2):(15-25). More preferably, the plant extract is a mixture of hop extract, plum extract, and cocoa extract in a mass ratio of (10-12):(1-2):(18-20).

[0028] Preferably, the composite liquid contains the following components: 3-7% amino acids, 0.5-2% organic acids, 2-7% fragrance substances, 23.5-42% plant extracts, and the remainder being solvent. More preferably, the composite liquid contains the following components: 3.5-5.5% amino acids, 1-1.5% malic acid, 3.5-5% fragrance substances, 29-34% plant extracts, and the remainder being solvent.

[0029] Further, in step S5, the soaking conditions are: temperature 40-50℃, time 1-7h. Preferably, the soaking conditions are: temperature 45-50℃, time 2-4h.

[0030] Further, in step S5, the solid-liquid ratio of the burley tobacco leaves to the pretreatment solution and the soaking solution is 1:8-20 g / mL. Preferably, in step S5, the solid-liquid ratio of the burley tobacco leaves to the pretreatment solution and the soaking solution is 1:10-15 g / mL.

[0031] Furthermore, in step S6, the moisture adjustment refers to first dehydrating the burley tobacco and then placing it in a constant temperature and humidity chamber to adjust the moisture content. The temperature of the constant temperature and humidity chamber is 100-160℃ and the humidity is ≤15%.

[0032] The present invention also provides the application of the burley tobacco prepared by the above method in cigarettes.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] 1. This invention utilizes the characteristics of burley tobacco leaves, such as thinness, loose structure, and good absorption of fragrance, to process burley tobacco. The chemical composition of the processed burley tobacco is more harmonious, and it can be endowed with a flue-cured tobacco aroma. The characteristic aroma is significantly reduced, the strength is lowered, and the aftertaste is significantly improved, thus improving the sensory quality of burley tobacco and greatly enhancing the applicability of burley tobacco leaves in cigarette formulation.

[0035] 2. This invention pre-treats burley tobacco leaves by adding sodium carbonate and sodium tartrate to the pre-treatment solution, which can maximize the dissolution of impurities such as alkaloids, reduce the alkaloid content, and not destroy the decomposition of sugars. This can improve the sugar-alkaloid ratio, reduce the characteristic aroma of burley tobacco, and improve sensory quality.

[0036] 3. The present invention performs cold air treatment after the pretreatment of burley tobacco, which can effectively improve the permeability of the cell membrane of burley tobacco leaves, so as to fully release the active ingredients in the tobacco leaves, thereby promoting the formation of more aroma substances, reducing the special smell of burley tobacco, increasing the smoothness of the smoke, and improving the sensory quality of burley tobacco.

[0037] 4. This invention adds a specific ratio of amino acids, along with sugars and plant extracts, to the Burley tobacco leaves during the soaking process. This makes the chemical composition of the treated Burley tobacco more harmonious, increases the amount of sugars, promotes the degradation of carotenoid macromolecules in the tobacco leaves, increases the production of aroma substances, enriches the aroma of the tobacco leaves, gives the tobacco leaves a unique sweet and floral aroma, reduces the special odor of Burley tobacco, and makes the aroma more harmonious. Detailed Implementation

[0038] The following non-limiting embodiments are intended to enable those skilled in the art to gain a more comprehensive understanding of the present invention, but do not limit the invention in any way. The following content is merely an exemplary description of the scope of protection of the present invention, and those skilled in the art can make various changes and modifications to the invention based on the disclosed content, which should also fall within the scope of protection of the present invention.

[0039] The present invention will be further described below by way of specific embodiments. Unless otherwise specified, all chemical reagents used in the embodiments of the present invention are obtained through conventional commercial means.

[0040] Example 1

[0041] A method for improving the usability of burley tobacco leaves includes the following steps:

[0042] S1. Prepare a pretreatment solution, wherein the pretreatment solution comprises, by mass percentage: 50% ethanol, 8% sodium tartrate, and the remainder water.

[0043] S2. Place the Burley tobacco leaves into the pretreatment solution at a solid-liquid ratio of 1:20 g / mL and soak at 65℃ for 10 min to complete the pretreatment.

[0044] S3. Take out the Burley tobacco leaves and treat them for 2 hours under the conditions of cold air temperature of 15℃ and cold air speed of 8m / s.

[0045] S4. Dissolve lactose in water, add compound solution to obtain soaking solution, wherein the amount of lactose is 2% of the water mass and the amount of compound solution is 4% of the water mass.

[0046] S5. Place the Burley tobacco leaves into the soaking solution at a solid-liquid ratio of 1:20 g / mL and soak at 50℃ for 1 hour to complete the soaking treatment.

[0047] S6. Remove the Burley tobacco leaves, dehydrate them using a centrifuge, and then place them in a constant temperature and humidity chamber to adjust the moisture content to 16%, thus completing the processing.

[0048] The compound liquid contains the following components: 3% amino acids (glutamic acid, glycine, alanine and aspartic acid in a mass ratio of 1:0.5:0.5:1), 2% malic acid, 7% flavoring substances (2-methylpyrazine, 2,3-dimethylpyrazine, fennel oil and anise oil in a mass ratio of 0.2:0.2:1:0.5), 15% hop extract, 2% plum extract, 25% cocoa extract, and the balance propylene glycol.

[0049] Example 2

[0050] Another method to improve the availability of Burley tobacco includes the following steps:

[0051] S1. Prepare a pretreatment solution, wherein the pretreatment solution comprises, by mass percentage: 60% ethanol, 4% sodium tartrate, and the remainder water.

[0052] S2. Place the Burley tobacco leaves into the pretreatment solution at a solid-liquid ratio of 1:10 g / mL and soak at 65℃ for 20 minutes to complete the pretreatment.

[0053] S3. Take out the Burley tobacco leaves and treat them for 2 hours under the conditions of cold air temperature of 15℃ and cold air speed of 8m / s.

[0054] S4. Dissolve fructose in water, add compound solution to obtain soaking solution, wherein the amount of lactose is 2% of the water mass and the amount of compound solution is 4% of the water mass.

[0055] S5. Place the Burley tobacco leaves into the soaking solution at a solid-liquid ratio of 1:10 g / mL and soak at 50℃ for 2 hours to complete the soaking treatment.

[0056] S6. Remove the Burley tobacco leaves, dehydrate them using a centrifuge, and then place them in a constant temperature and humidity chamber to adjust the moisture content to 16%, thus completing the processing.

[0057] The compound liquid contains the following components: 3.5% amino acids (glutamic acid, glycine, alanine and aspartic acid in a mass ratio of 1:1:1:1), 1.5% malic acid, 3.5% flavoring substances (2-methylpyrazine, 2,3-dimethylpyrazine, fennel oil and anise oil in a mass ratio of 0.5:0.5:2:1), 12% hop extract, 2% plum extract, 20% cocoa extract, and the balance propylene glycol.

[0058] Example 3

[0059] Another method to improve the availability of Burley tobacco includes the following steps:

[0060] S1. Prepare a pretreatment solution, wherein the pretreatment solution comprises, by mass percentage: 70% ethanol, 5% sodium tartrate, and the remainder water.

[0061] S2. Place the Burley tobacco leaves into the pretreatment solution at a solid-liquid ratio of 1:15 g / mL and soak at 60℃ for 20 min to complete the pretreatment.

[0062] S3. Remove the burley tobacco leaves and treat them for 0.5 hours under the conditions of cold air temperature of 10℃ and cold air speed of 10m / s.

[0063] S4. Dissolve sucrose in water, add compound solution to obtain soaking solution, wherein the amount of lactose used is 3% of the water mass, and the amount of compound solution used is 5% of the water mass;

[0064] S5. Place the Burley tobacco leaves into the soaking solution at a solid-liquid ratio of 1:15 g / mL and soak at 45℃ for 4 hours to complete the soaking treatment.

[0065] S6. Remove the Burley tobacco leaves, dehydrate them using a centrifuge, and then place them in a constant temperature and humidity chamber to adjust the moisture content to 16%, thus completing the processing.

[0066] The compound liquid contains the following components: 5.5% amino acids (glutamic acid, glycine, alanine and aspartic acid in a mass ratio of 1:1.5:1.5:2), 1% malic acid, 5% flavoring substances (2-methylpyrazine, 2,3-dimethylpyrazine, fennel oil and anise oil in a mass ratio of 0.8:0.7:2.5:1.5), 10% hop extract, 1% plum extract, 18% cocoa extract, and the balance being propylene glycol.

[0067] Example 4

[0068] Another method to improve the availability of Burley tobacco includes the following steps:

[0069] S1. Prepare a pretreatment solution, wherein the pretreatment solution comprises, by mass percentage: 75% ethanol, 3% sodium tartrate, and the remainder water.

[0070] S2. Place the Burley tobacco leaves into the pretreatment solution at a solid-liquid ratio of 1:15 g / mL and soak at 55℃ for 30 min to complete the pretreatment.

[0071] S3. Remove the burley tobacco leaves and treat them for 0.5 hours under the conditions of cold air temperature of 10℃ and cold air speed of 10m / s.

[0072] S4. Dissolve glucose in water, add compound solution to obtain soaking solution, wherein the amount of lactose is 3% of the water mass and the amount of compound solution is 5% of the water mass.

[0073] S5. Place the Burley tobacco leaves into the soaking solution at a solid-liquid ratio of 1:8 g / mL and soak at 45℃ for 4 hours to complete the soaking treatment.

[0074] S6. Remove the Burley tobacco leaves, dehydrate them using a centrifuge, and then place them in a constant temperature and humidity chamber to adjust the moisture content to 16%, thus completing the processing.

[0075] The compound liquid contains the following components: 7% amino acids (glutamic acid, glycine, alanine and aspartic acid in a mass ratio of 1:2:1.5:3), 0.5% malic acid, 2% flavoring substances (2-methylpyrazine, 2,3-dimethylpyrazine, fennel oil and anise oil in a mass ratio of 1:1:0.5:1:2), 8% hop extract, 0.5% plum extract, 15% cocoa extract, and the balance being propylene glycol.

[0076] Comparative Example 1

[0077] Another method to improve the usability of Burley tobacco leaves differs from Example 2 only in the pretreatment solution; sodium tartrate was not added to the pretreatment solution in this comparative example.

[0078] Comparative Example 2

[0079] Another method to improve the usability of Burley tobacco leaves differs from Example 2 only in the pretreatment solution; no ethanol was added to the pretreatment solution in this comparative example.

[0080] Comparative Example 3

[0081] Another method to improve the usability of Burley tobacco leaves differs from Example 2 only in that the amino acid formulation in the compound liquor is different. In this comparative example, the amino acids in the compound liquor contain glutamic acid, glycine, alanine and aspartic acid in a mass ratio of 1:0.3:0.3:0.5.

[0082] Comparative Example 4

[0083] Another method to improve the usability of Burley tobacco leaves differs from Example 2 only in that the amino acid formulation in the compound liquor is different. In this comparative example, the amino acids in the compound liquor contain glutamic acid, glycine, alanine and aspartic acid in a mass ratio of 1:2.5:2:3.5.

[0084] Comparative Example 5

[0085] Another method to improve the usability of Burley tobacco leaves differs from Example 2 only in that the amino acid formulation in the compound liquor is different. In this comparative example, the amino acids in the compound liquor contain tyrosine, isoleucine, and leucine in a mass ratio of 1:0.5:0.5.

[0086] Comparative Example 6

[0087] Another method to improve the usability of Burley tobacco leaves differs from Example 2 only in that high-temperature baking is used instead of cold air treatment in this comparative example, with the high-temperature baking temperature being 120°C.

[0088] Comparative Example 7

[0089] Another method to improve the usability of burley tobacco leaves differs from Example 2 only in that the burley tobacco is directly treated with cold air in this comparative example, without any pretreatment step; the cold air treatment conditions are the same as in Example 2.

[0090] Comparative Example 8

[0091] Another method to improve the usability of Burley tobacco leaves differs from Example 2 only in that the Burley tobacco leaves in this comparative example are directly soaked in the soaking solution without pretreatment or cold air treatment steps.

[0092] This invention uses Chongqing Burley tobacco leaves as an example (the ratio of each part of the Chongqing Burley tobacco leaf is middle:upper:lower = 3:1:1). The Burley tobacco is processed according to the above method, and the results are as follows:

[0093] Experimental Example 1

[0094] The burley tobacco leaves obtained according to the methods described in Examples 1-4 and Comparative Examples 1-8 were cut into uniform shreds using a shredder. Changes in the chemical composition of the tobacco leaves before and after treatment were measured. The total sugar and reducing sugar content were determined using the continuous flow method of YC / T159-2002; the total alkaloid content was determined using the continuous flow method of YC / T160-2002; the total nitrogen content was determined using the continuous flow method of YC / T161-2002; and the potassium content was determined using YC / T... The flame photometry method of YC / T161-2003 was used for the determination of chlorine content, the continuous flow method of YC / T161-2002 was used for the determination of starch content, the anthrone method was used for the determination of pectin content, the Klason method was used for the determination of lignin content, the Klason method was used for the determination of protein content, the Kordahl method of YC / T166-2003 was used for the determination of total volatile alkaloid content, the YC / T35-1996 method was used for the determination of chlorogenic acid, hyoscyamine, and rutin content, and high performance liquid chromatography was used for the determination of chlorogenic acid, hyoscyamine, and rutin content.

[0095] The results are shown in Tables 1 and 2 below.

[0096] Table 1

[0097]

[0098]

[0099] As shown in the table, the Burley tobacco leaves treated by the method described in this invention exhibit significantly increased total sugar and reducing sugar content, and significantly decreased total nitrogen, protein, starch, and pectin content. The sugar-to-alkali ratio increased from 0.43 to 1.63-2.02, a substantial improvement. The Schmuck value increased from 0.07 to 0.16-0.19, indicating a greater increase in the Schmuck value. This suggests that the chemical composition of the Burley tobacco leaves treated by the method described in this invention is more harmonious, the characteristic Burley aroma is significantly reduced, the strength is lowered, the aftertaste is significantly improved, and the quality is enhanced, greatly improving the applicability of Burley tobacco leaves in cigarette formulations.

[0100] Table 2

[0101] project Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 Comparative Example 8 Total sugar (%) 1.78 1.90 1.98 2.04 1.91 2.07 1.88 1.81 Reducing sugar (%) 1.02 1.35 1.58 1.60 1.48 1.72 1.24 1.32 Total alkaloids (%) 2.28 2.06 1.64 1.61 1.70 1.73 2.30 2.35 Total nitrogen (%) 3.07 2.98 2.81 2.74 2.62 2.70 2.78 2.86 chlorine(%) 0.32 0.28 0.40 0.36 0.33 0.27 0.25 0.22 Potassium (%) 1.87 1.60 1.88 2.07 2.29 1.48 1.55 1.90 Sugar-base ratio 0.78 0.92 1.21 1.27 1.12 1.20 0.82 0.77 protein(%) 16.05 15.86 16.65 17.11 18.04 15.05 14.90 16.01 Schmuck value 0.11 0.12 0.12 0.12 0.11 0.14 0.13 0.11 pH 5.50 5.62 5.60 5.70 5.56 5.54 5.62 5.65 Nitrogen-base ratio 1.35 1.45 1.71 1.70 1.54 1.56 1.21 1.22 Potassium chloride ratio 5.84 5.71 4.70 5.75 6.94 5.48 6.20 8.64 Total volatile bases (%) 0.42 0.37 0.41 0.36 0.44 0.38 0.38 0.40 Chlorogenic acid (%) 0.73 0.80 0.68 0.61 0.40 0.44 0.39 0.32 Hyoscyamine (%) 0.04 0.05 0.03 0.05 0.05 0.05 0.04 0.05 Rutin (%) 0.20 0.25 0.26 0.24 0.20 0.18 0.26 0.14 starch(%) 0.51 0.50 0.68 0.62 0.71 0.38 0.35 0.53 Pectin (%) 11.0 10.9 11.3 11.2 11.6 10.4 10.8 11.1 Lignin (%) 4.07 4.21 4.30 4.28 4.05 4.30 4.26 4.11

[0102] As shown in the table, the difference between Comparative Examples 1 and 2 and Example 2 lies in the different formulations of the pretreatment solution. According to the experimental results, the addition of sodium carbonate and sodium tartrate to the pretreatment solution helps to increase the total sugar and reducing sugar content in Burley tobacco leaves, reduce the content of total alkaloids, total nitrogen, protein, starch and pectin, and increase the sugar-alkaloid ratio and Schmuck value of Burley tobacco leaves.

[0103] The difference between Comparative Examples 3-5 and Example 2 lies in the different formulations of the compound liquid. According to the experimental results, adding amino acids with a specific formulation to the compound liquid helps to reduce the content of total alkaloids, total nitrogen, and protein, and increase the sugar-alkali ratio of Burley tobacco leaves.

[0104] The difference between Comparative Examples 6-8 and Example 2 lies in the different pretreatment and cold air treatment steps. The experimental results show that the pretreatment of Burley tobacco leaves and the subsequent cold air treatment have a certain beneficial effect on reducing the content of total nitrogen, total alkaloids, and protein in Burley tobacco leaves.

[0105] Experimental Example 2

[0106] Neutral aroma components in burley tobacco leaves treated with the methods described in Examples 1-4 and Comparative Examples 1-8 were determined by GC / MS. The steps were as follows: 10.0 g of tobacco sample and 1.0 g of citric acid were added to a 500 mL round-bottom flask, followed by 350 mL of distilled water and 0.5 mL of internal standard nitrobenzene (0.700 g of nitrobenzene was weighed and diluted to a 100 mL volumetric flask, and 5 mL of this solution was diluted to a 100 mL volumetric flask with dichloromethane); 40 mL of dichloromethane was added to a 250 mL round-bottom flask; the 250 mL round-bottom flask was heated in a 60 °C water bath and extracted using a simultaneous distillation-extraction apparatus for 2.5 h; the organic phase was collected and approximately 10 g of anhydrous sodium sulfate was added, shaken well, and dried until the solution was clear; the anhydrous sodium sulfate was washed twice with dichloromethane; the solution was concentrated to approximately 1 mL at 60 °C; and finally, the results were identified by GC / MS and the NIST database was searched for qualitative analysis.

[0107] The results are shown in Table 3 below.

[0108] Table 3

[0109]

[0110]

[0111] Thirty-four neutral volatile components in Burley tobacco leaves were identified using GC / MS, which can be categorized into carotenoid degradation products, cephalosporin degradation products, chlorophyll degradation products, phenylalanine cleavage products, and browning reaction products. Among these, carotenoid degradation products are one of the important sources of aroma in Burley tobacco. The results in the table above show that the treatment of Burley tobacco leaves using the method described in this invention increases the amount of carotenoid degradation products and the content of neutral aroma substances.

[0112] Experimental Example 3

[0113] The burley tobacco leaves obtained by the methods described in Examples 1-4 and Comparative Examples 1-8 were rolled into cigarettes according to existing cigarette production processes. The proportion of burley tobacco leaves added was 5%. The sensory quality evaluation of cigarettes was carried out with reference to the sensory quality evaluation criteria in GB 5606.4-2005 Cigarettes Part 4: Sensory Technical Requirements. The specific evaluation criteria are shown in Table 4.

[0114] Table 4

[0115]

[0116] According to the evaluation criteria in Table 4, professional sensory evaluators scored the sensory quality of each example cigarette, and the average value was taken as the final score. The sensory quality evaluation scores of each example cigarette are shown in Table 5.

[0117] Table 5

[0118]

[0119]

[0120] The results showed that the characteristic aroma of the burley tobacco leaves treated by the method described in this invention was significantly reduced, the irritation was decreased, the strength was moderate, the aftertaste was significantly improved, and the sensory quality was high. The sensory evaluations of Comparative Examples 1-8 all showed a decline. Therefore, the treatment method provided by this invention effectively improves the quality of burley tobacco leaves and greatly enhances their applicability in cigarette formulations.

[0121] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A method for improving the usability of Burley tobacco leaves, characterized in that, Includes the following steps: S1. Dissolve ethanol and sodium tartrate in water to obtain a pretreatment solution; S2. Place the burley tobacco leaves into the pretreatment solution for pretreatment; S3. After pretreatment, remove the product and treat it with cold air. S4. Dissolve the sugar in water, add it to the compound solution and mix well to obtain the soaking solution; S5. After cold air treatment, burley tobacco leaves are soaked in the soaking solution. S6. After soaking, remove the Burley tobacco leaves, dehydrate them and adjust the moisture content to 16-18%, and the processing is complete. The pretreatment solution contains ethanol, sodium tartrate, and water; The composite liquid contains amino acids, organic acids, fragrance substances, plant extracts, and solvents; The amino acids comprise glutamic acid, glycine, alanine, and aspartic acid in a mass ratio of 1:(0.5-2):(0.5-1.5):(1-3). The organic acid is at least one of citric acid, malic acid, and lactic acid, and the organic acid is food grade; the flavoring substance comprises 2-methylpyrazine, 2,3-dimethylpyrazine, fennel oil, and anise oil in a mass ratio of (0.2-1):(0.2-1):(1-3):(0.5-2); the plant extract comprises hop extract, plum extract, and cocoa extract in a mass ratio of (8-15):(0.5-2):(15-25); the solvent is propylene glycol. The pretreatment solution, by mass percentage, contains: 50-75% ethanol, 3-8% sodium tartrate, and the remainder water. The conditions for the cold air treatment are: cold air temperature 10-15℃, cold air speed 8-10m / s, and time 0.5-2h.

2. The method according to claim 1, characterized in that, In steps S1 and S4, the sugar is at least one of fructose, lactose, glucose, maltose, invert sugar, sucrose, honey, and fruit syrup.

3. The method according to claim 1, characterized in that, In step S4, the amount of the sugar is 1-4% of the water mass, and the amount of the composite liquid is 1-7% of the water mass.

4. The method according to claim 1, characterized in that, The composite liquid contains, by mass percentage: 3-7% amino acids, 0.5-2% organic acids, 2-7% fragrance substances, 23.5-42% plant extracts, and the remainder being solvent.

5. The use of burley tobacco leaves prepared by the method according to any one of claims 1-4 in cigarettes.

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