CN112120265B

CN112120265B - Processing method of leaf group formula containing aged tobacco leaves

Info

Publication number: CN112120265B
Application number: CN202010869013.8A
Authority: CN
Inventors: 徐达; 苏加坤; 蔡继宝; 罗海涛; 何力; 任周营; 罗娟敏; 钟宇生
Original assignee: China Tobacco Jiangxi Industrial Co Ltd
Current assignee: China Tobacco Jiangxi Industrial Co Ltd
Priority date: 2020-08-26
Filing date: 2020-08-26
Publication date: 2022-01-21
Anticipated expiration: 2040-08-26
Also published as: CN112120265A

Abstract

The invention discloses a processing method of a leaf group formula containing long-age tobacco leaves, which comprises the following steps: (1) establishing a database of the yield of the volatile oil of the single tobacco and the total amount of the neophytadiene and the phytofuran; (2) grouping the tobacco leaves; (3) grouping according to the formula of the cigarette leaf group; (4) the tobacco leaves of each group are mixed evenly and stored after being added with flavor. According to the method, the volatile oil yield and the total amount of the new plant diene and the plant furan are taken as the judgment standards of the quality of the old tobacco leaves in a breakthrough manner, and the detection results of the tobacco leaves of all grades aged for 12 months are selected as the reference samples, so that the tobacco leaves of different grades have independent reference objects, the feasibility is high, and the grouping reason is more reasonable. The processing of the leaf group formula containing the long-term tobacco leaves is completed by a complex enzyme technology, a characteristic essence and spice adding technology, a tobacco leaf grouping technology and a process of re-walking a thin plate line or an air flow line, so that the aroma quality of the leaf group formula is effectively improved, miscellaneous gas and stimulation are reduced, the odd taste of sour is eliminated, and the problems of transportation, timeliness and tobacco leaf loss of industrial enterprises caused by secondary redrying adopted by most industrial enterprises are solved.

Description

Processing method of leaf group formula containing aged tobacco leaves

Technical Field

The invention belongs to the technical field of tobacco processing, and particularly relates to a processing method of a leaf group formula containing aged tobacco leaves.

Background

The long-aged tobacco leaves, as the name suggests, refer to low-availability tobacco leaves with reduced total sugar, lost flavor components and even mildewed tobacco leaves with overlong storage time due to poor quality and other reasons. The tobacco leaves have less aroma, sourness and strange taste during smoking evaluation, so that the application value of the tobacco leaves in cigarettes is reduced. Due to the fact that the quality of the tobacco leaves is further reduced due to continuous storage of the long-term tobacco leaves, a simple method is found, and the screening and the grade classification of the long-term tobacco leaves are very important. The Schenk value, the sugar-base ratio and the sugar-nitrogen ratio are popular methods for evaluating the quality of tobacco leaves at present, but in the practical application of evaluating the long-term tobacco leaves, in addition to the loss of sugar, the loss of volatile tobacco flavor substances, mildew and the like in the long-term storage process of the tobacco leaves are considered, so most tobacco industry companies carry out classification by sensory evaluation.

The processing of long-aged tobacco leaves is one of the difficulties which plague all tobacco industry companies, because the tobacco leaves are stored for about 3 years, the smoke quality is improved mainly through the aging effect of the tobacco leaves, and along with the prolonging of the storage time, the tobacco leaves are reduced in quality, easy to be broken and reduced in availability year by year due to the excessive consumption of sugar substances caused by the volatilization of flavor components. The virtuous cycle of consuming the existing long-term tobacco leaves and forming low-availability tobacco leaves is an important reality faced by the industry at present.

The tobacco volatile oil is the main flavor component of tobacco leaves and comprises volatile acids, alcohols, carbonyls, esters, heterocyclic chemicals and the like, wherein the neophytadiene and plant furan are compounds with the highest volatile aroma quality content in the flue-cured tobacco and have faint scent. Research shows that the neophytadiene can directly enter smoke when the tobacco is burnt, and has the functions of reducing irritation and making the smoke mellow. The new phytodiene is an important flavoring agent in the tobacco body, and has the function of enabling other volatile aroma substances, aroma substances and added aroma components in the tobacco to enter smoke. The neophytadiene can be further decomposed and converted into plant furan, and has fragrant smell. These substances all have a positive influence on the formation of the faint scent of the flue-cured tobacco.

At present, for the treatment of the old tobacco leaves, domestic industrial enterprises have taken some measures to deal with the old tobacco leaves, and patent CN106858696A adopts a module grouping secondary redrying process to directly improve the quality of the old tobacco leaves, so that a certain effect is achieved, but secondary redrying can bring some problems to the industrial enterprises: 1) the transportation and time cost is increased; 2) the tobacco leaves have various grades and insufficient targeted operability of secondary redrying; 3) at present, the yield of the long-age tobacco leaves after being redried is only 50-70%, and the economic loss is large.

Disclosure of Invention

According to the method, the volatile oil yield and the total amount of the new plant diene and the plant furan are taken as the judgment standards of the quality of the old tobacco leaves in a breakthrough manner, and the detection results of the tobacco leaves of all grades aged for 12 months are selected as the reference samples, so that the tobacco leaves of different grades have independent reference objects, the feasibility is high, and the grouping reason is more reasonable.

In addition, in consideration of the problems of transportation and timeliness caused by secondary redrying, the quality of the old tobacco leaves is improved by processing the old tobacco leaves in a mode of adding a quality-improving preparation and preprocessing a tobacco shred. According to the tobacco leaf grading result, a thin plate line or an airflow line is selected, the tobacco leaf drying time and the tobacco leaf drying temperature can be adjusted according to different tobacco leaf qualities, and the operability is high.

The invention discloses a processing method of a leaf group formula containing long-age tobacco leaves, which comprises the following steps:

step one, establishing a database, and completing sampling and detection of single cigarettes of each grade after the new cigarettes are put into a tobacco strip warehouse and aged for 12 months, wherein detection indexes comprise volatile oil yield, total amount of new phytodiene and plant furan, and the results are respectively set as X0 and Y0.

And step two, when single tobacco with the storage year of more than 3 years exists in the leaf group formula, the yield of the volatile oil, the total amount of neophytadiene and plant furan are detected again before use, and the results are named as X1 and Y1 respectively. Grouping the tobacco leaves according to the comparison results of X1 and Y1 with X0 and Y0:

a. when X1 is more than 0.9X0 and Y1 is more than 0.9Y0, the tobacco leaves are determined to be type A;

b. when X1 is more than 0.9X0, 0.8Y0 is less than Y1 and less than 0.9Y0, the tobacco leaves are determined to be in B type;

c. when X1 is more than 0.9X0 and Y1 is less than 0.8Y0, the tobacco leaves are determined to be the C type;

d. when 0.8X0< X1<0.9X0 and Y1>0.85Y0, the tobacco leaves are determined to be in B type;

e. when 0.8X0< X1<0.9X0 and Y1<0.85Y0, the tobacco leaves are determined to be in C class;

f. when the yield of the volatile oil is X1 to be less than 0.8X0 or the tobacco leaves with mildew taste are determined as tobacco leaves C;

step three, during cigarette production, classifying the tobacco leaves in the leaf group formula according to the feeding proportion according to the cigarette leaf group formula, and carrying out grading treatment:

A. the method is characterized by comprising the following steps of (1) preprocessing low-availability tobacco leaves B, wherein the preprocessing method comprises the following steps: after moisture regaining and shredding, adding a quality improving agent B, walking a thin plate line, drying the shreds until the moisture content is 12-13%, and storing for later use. The preferable water content is 12-12.5%.

B. The method is characterized by comprising the following steps of (1) preprocessing low-availability tobacco leaves C, wherein the preprocessing method comprises the following steps: and (3) after moisture regaining and shredding, adding a quality improving agent C, passing through an air flow line, drying the shreds until the moisture content is about 12-13%, and storing for later use. The water content is preferably 12.5 to 13%.

C. Feeding tobacco leaves A, shredding after moisture regain, adding or not adding pretreated tobacco leaves B, adding sugar A, then feeding a sheet line, and drying until the moisture content is about 12-13%. The preferable water content is 12-12.5%.

And step four, uniformly mixing the expanded cut tobacco, the cut stems and the tobacco leaves A, B and C processed in the step three according to the formula ratio of the tobacco leaves on a tobacco shred preparation line, adding fragrance, and entering a tobacco shred storage cabinet to obtain the tobacco shred storage cabinet.

The standard of the tobacco grouping is obtained by long-time experimental data accumulation and analysis, generally speaking, the yields of volatile oil extraction of tobacco leaves in different grades and different production places are different and have larger difference, but the exception is the rising and falling trend of the yield of the volatile oil, the yield and characteristic components (total amount of new plant diene and plant furan) begin to decrease with the increase of time probably because of the aging effect, the tobacco leaves with better quality can still reach more than 90% X0 after being stored for 4-5 years according to sensory evaluation results and detection data analysis, and can be classified as tobacco leaves A; and the tobacco leaves with poor quality are probably fast in quality reduction due to insufficient innate and severe storage environment, and are classified into tobacco leaves of B class or even C class after being stored for 3-4 years. Therefore, the method provided by the patent needs continuous detection work accumulation to be obtained and implemented.

The processing method of the leaf group formula containing the long-age tobacco leaves is characterized in that the yield of the volatile oil is obtained by extracting the volatile oil by adopting a simultaneous distillation extraction method, collecting the volatile oil by using dichloromethane, removing the solvent by evaporation and concentration and counting. Further, in the distillation extraction equipment, a 50ml flask is adopted at the volatile oil collecting side, and 20ml dichloromethane is added into the volatile oil collecting side; and (3) adding zeolite and 200g of tobacco powder into a 500-1000 ml flask on the tobacco leaf extraction side, and heating the flask to boil for 4 hours for extraction.

The processing method of the leaf group formula containing the aged tobacco leaves is characterized in that the total amount of the new plant diene and the plant furan is obtained according to GC-MS detection and is quantified through an internal standard method.

The processing method of the leaf group formula containing the aged tobacco leaves is characterized in that the quality-improving preparation B consists of the following substances (based on the mass of the tobacco leaves): 0.01-0.05% of medlar extract, 0.01-0.05% of Chinese date extract, 0.01-0.05% of dark plum extract, 0.01-0.05% of carob bean extract, 0.01-0.1% of tobacco extract, 0.005-0.02% of oil of cloth withered leaves, 0.01-0.2% of molasses extract, 0.01-0.05% of laccase, 0.001-0.01% of 2-acetyl pyrrole, and propylene glycol and water as solvents.

The processing method of the leaf group formula containing the aged tobacco leaves is characterized in that the quality-improving preparation C comprises the following substances (based on the quality of the tobacco leaves): 0.01-0.05% of medlar extract, 0.01-0.05% of Chinese date extract, 0.01-0.05% of dark plum extract, 0.01-0.05% of carob bean extract, 0.01-0.1% of tobacco extract, 0.005-0.02% of oil of cloth withered leaves, 0.01-0.2% of molasses extract, 0.01-0.05% of laccase, 0.001-0.01% of 2-acetyl pyrrole, 0-0.05% of flavourzyme, 0-0.05% of alkaline protease, 0-0.02% of lipase, 0-0.02% of beta-glucosidase, and propylene glycol and water as solvents.

The sugar material A is prepared by compounding honey, tobacco extract and liquorice extract according to the weight ratio of 5:1:2, and the feeding amount of the sugar material A is 2% of the weight of tobacco leaves.

When the tobacco leaves are treated, the tobacco shred charging is mainly adopted, but not the tobacco sheet charging, and the main reason is that biological enzyme is added into the quality-improving preparation, so that the catalytic treatment surface area is increased by the tobacco shred charging, and the catalytic efficiency can be improved.

The processing method of the leaf group formula containing the aged tobacco leaves is characterized in that the cut tobacco drying process of the thin plate line is about 135-145 ℃ for 5-10 min.

The processing method of the leaf group formula containing the aged tobacco leaves is characterized in that the tobacco drying process of the airflow line is about 220-290 ℃ for 8-12 s.

The differentiated upgrading agent B and upgrading agent C adopted by the patent are processed aiming at different types of aged tobacco leaves. The main problems of the B-type tobacco leaves are that the degradation of saccharides and the loss of volatile components cause the reduction of tobacco aroma, and the quality of the B-type tobacco leaves is between the A-type tobacco leaves and the C-type tobacco leaves. The C-type tobacco leaves have the main problems that the storage time is too long, the moldy and strange taste is caused, the filling value of the C-type tobacco leaves is poor, and the C-type tobacco leaves are easy to break. Therefore, the quality improving preparation B is mainly supplemented by carbohydrate substances and tobacco or flavor substances similar to tobacco, the laccase is mainly added for reducing the wood gas of the tobacco, the treatment of the quality improving preparation B is relatively mild, the pretreatment temperature of a sheet line is low, and the temperature is 135-145 ℃; in addition to the supplement of carbohydrate substances and flavor substances of tobacco or similar tobacco, the flavor protease and the alkaline protease are mainly used for decomposing tobacco protein and increasing the sugar-nitrogen ratio, decomposed free amino acid can perform Maillard reaction in the tobacco shred drying process to improve the fragrance of the tobacco, and the addition of the lipase is mainly used for catalyzing sour substances such as acetic acid and lactic acid generated by long-term storage of the long-term tobacco leaves to be esterified into organic acid-ester flavor substances so as to balance the sour strange taste brought by the long-term tobacco leaves. The temperature of the airflow line is higher than that of the thin plate line, generally 220-290 ℃, and the mildew taste of the tobacco leaves can be effectively removed through experimental verification, so the tobacco leaves C with the worst quality are generally treated by the airflow line.

Meanwhile, after the pretreatment of the tobacco leaves B and C is finished, the pretreated tobacco leaves B and A can be mixed, sugar is added, the thin plate lines are rewound, cut tobacco is dried, and then the mixture is uniformly mixed with the puffed tobacco shreds, the cut stems and the tobacco leaves C according to the formula of the tobacco shreds, added with fragrance and then enters a shred storage cabinet. Whether the operation is selected or not is determined according to the filling value and the shredding rate of the tobacco leaves after the B-type pretreatment of the tobacco leaves. Re-running the sheet line is beneficial to re-improving the smoking quality of the old tobacco leaves, and the problem caused by re-running the sheet line is that the shredded rate is increased.

Detailed Description

Example 1

The tobacco leaf group formula of the cigarettes with the JS specifications is selected for example, wherein 24 single-material cigarettes with different grades exist, and specifically as shown in Table 1, according to the tobacco leaf grouping method disclosed by the invention, 11 single-material cigarettes are long-aged tobacco leaves which are 5-6 years away from the current (2020), wherein 6B-type tobacco leaves exist, and 5C-type tobacco leaves exist. The treatment modes of 13A-type tobacco leaves and slices belong to the conventional treatment in the industry, so that the treatment modes are not listed one by one. In addition, the puffed tobacco shreds and the cut stems belong to ginseng matching fillers.

TABLE 1 leaf composition formula of JS-standard cigarettes and relevant chemical index condition of single cigarette in each grade

And (3) taking a single tobacco grade in A, B, C three types of tobacco leaves in the JS leaf group formula as a representative, and inspecting the difference between the classification standard method and the actual sensory evaluation. From table 2, it can be known that the quality of the tobacco leaves of yunnan qujing land mixed threshing C2F 2014 is in a slow rising trend from 2014 to 2016, and then gradually decreases with the increase of years, and the tobacco leaves are reduced from class a to class B according to the classification standard of the tobacco leaves (0.8X0< X1<0.9X0, Y1>0.85Y0) in 2020, which is consistent with the sensory evaluation result. The same is true for the other 2 kinds of single cigarette, which are not described in detail herein.

TABLE 2 JS specification cigarette X1, Y1, cigarette flavor quality change with time in each grade of representative single cigarette

Note: the more "+" indicates the functional effect, the better the functional effect

The tobacco leaf group formulas in the table 1 are used for processing, the JS leaf group tobacco shreds which are not prepared by the grouping processing technology are used in a comparative example 1, and the JS leaf group tobacco shreds which are prepared by the technology are used in examples 2-4, and finally the JS leaf group tobacco shreds are evaluated one by adopting a sensory evaluation method.

Comparative example 1

All the single-material cigarettes in the JS leaf group are processed through an industry-conventional sheet line, materials are added (sugar material A, specifically honey, tobacco extract and liquorice extract are compounded according to a weight ratio of 5:1:2, the feeding amount is 2% of the weight of tobacco leaves), cut tobacco is dried until the moisture content is 12.5%, then the cut tobacco is mixed with expanded cut tobacco and cut stems according to a proportion, and the flavor is added, wherein the cut tobacco drying process of the sheet line is 140 ℃ and 8 min.

Example 2

A processing method of a leaf group formula containing long-aged tobacco leaves comprises the following steps:

f. when the yield of the volatile oil is X1 to be less than 0.8X0 or the tobacco leaves with mildew taste are determined as low-availability tobacco leaves C;

the 24 different grades of individual cigarettes were tested and grouped according to the method of steps one and two above, the specific method and results are given in example 1.

A. the method is characterized by comprising the following steps of (1) preprocessing the tobacco leaves B, wherein the preprocessing method comprises the following steps: after moisture regaining and shredding, quality improving agent B is added, a thin plate line is laid, and the shredded tobacco is dried until the moisture content is 12.5 percent and stored for later use.

B. The pretreatment is carried out on the C-type tobacco leaves, and the pretreatment method comprises the following steps: after moisture regaining and shredding, quality improving agent C is added, air flow line is removed, the shredded tobacco is dried until the moisture content is 12.5%, and the shredded tobacco is stored for later use.

C. Feeding tobacco leaves A, dampening and shredding, adding sugar A, then feeding a thin plate line, and drying until the moisture content is 12.5%.

The volatile oil is extracted by adopting a simultaneous distillation extraction method, and after the volatile oil is collected by dichloromethane, the solvent is removed by evaporation and concentration, and then the counting is carried out. The total amount of neophytadiene and phytofuran is obtained by GC-MS detection and quantified by an internal standard method.

The quality-improving preparation B consists of the following substances (based on the mass of tobacco leaves): 0.05% of medlar extract, 0.02% of Chinese date extract, 0.02% of dark plum extract, 0.01% of carob bean extract, 0.1% of tobacco extract, 0.005% of buchu leaf oil, 0.05% of molasses extract, 0.02% of laccase, 0.005% of 2-acetyl pyrrole, and propylene glycol and water as solvents.

The quality-improving preparation C consists of the following substances (based on the mass of tobacco leaves): 0.05% of medlar extract, 0.05% of Chinese date extract, 0.02% of dark plum extract, 0.01% of carob bean extract, 0.05% of tobacco extract, 0.005% of leaf oil of paraquat, 0.1% of molasses extract, 0.01% of laccase, 0.005% of 2-acetyl pyrrole, 0.05% of flavourzyme, 0.05% of alkaline protease, 0.02% of lipase, 0.02% of beta-glucosidase, and propylene glycol and water as solvents.

The sugar material A is as follows: the honey, the tobacco extract and the liquorice extract are compounded according to the weight ratio of 5:1:2, and the feeding amount is 2% of the weight of the tobacco leaves.

The cut tobacco drying process of the thin plate wire is about 135 ℃ for 8 min. The cut tobacco drying process of the airflow line is about 220 ℃ for 12 s.

Example 3

step one, the same as example 2.

Step two, the same as example 2;

B. The pretreatment is carried out on the C-type tobacco leaves, and the pretreatment method comprises the following steps: after moisture regaining and shredding, adding a quality improving agent C, moving away from an air flow line, drying the shredded tobacco until the moisture content is 13%, and storing for later use.

The upgrading agent B is the same as in example 2.

The upgrading agent C was the same as in example 2.

The sugar material A was the same as in example 2.

The cut tobacco drying process of the thin plate wire is about 140 ℃ for 8 min. The cut tobacco drying process of the airflow line is about 260 ℃ for 8 s.

Example 4

step one, the same as example 2.

Step two, the same as example 2.

A. preprocessing the tobacco leaves B, adding the quality-improving preparation B after moisture regain and shredding, moving the tobacco leaves to a thin plate line, drying the tobacco leaves until the moisture content is 12.5%, and storing for later use.

B. Pretreating tobacco leaves C, adding a quality-improving preparation C after moisture regain and shredding, feeding an air flow line, drying the tobacco until the moisture content is 13%, and storing for later use.

C. Feeding tobacco leaves A, dampening and shredding the tobacco leaves A, mixing the tobacco leaves A and the pretreated tobacco leaves B in proportion, adding sugar A, then feeding the tobacco leaves A into a sheet line, and drying the tobacco leaves A until the moisture content is 12.5%.

And step four, on the tobacco shred making line, uniformly mixing the puffed tobacco shreds, the cut stems and the tobacco leaves C processed in the step three as a blending material with the tobacco leaves A and the tobacco leaves B on the tobacco shred making line pretreated in the step three according to the formula ratio of the tobacco shreds, adding fragrance, and entering a shred storage cabinet to obtain the tobacco shred storage cabinet.

The upgrading agent B is the same as in example 2.

The upgrading agent C was the same as in example 2.

The sugar material A was the same as in example 2.

The cut tobacco drying process of the thin plate wire is at 140 ℃ for 8 min. The cut tobacco drying process of the airflow line is at 260 ℃ for 8 s.

Comparative example 2

The processing method is the same as that in the example 3, only in the step three, when the treatment is performed on the tobacco leaves B, C and A, the quality-improving agent B, the quality-improving agent C and the sugar material A are not added respectively.

Comparative example 3

The processing method is the same as that of the example 3, and only differs from the step three in that the quality-improving agent B is not added when the tobacco leaves are treated in a type B manner.

Comparative example 4

The processing method is the same as that of example 3, and only differs in that in the step three, the quality-improving agent C is not added when the tobacco leaves C are treated.

Comparative example 5

The processing method is the same as that of the example 3, and only in the step three, when the tobacco leaves C are treated, the upgrading agent B is added instead of the upgrading agent C.

In the test examples, the leaf group formulas are mixed in the same proportion, and the volatile oil extraction method, the total content detection method of neophytadiene and plant furan and the like are kept consistent, so that single-factor parallel investigation is carried out.

TABLE 3 JS leaf group sensory evaluation statistical chart in each test example

From the results in table 3, it is seen that the treatment effect of example 3 is the most excellent, and from the experimental results: the invention

1) The tobacco leaves with the musty taste and the strange flavor are C-type tobacco leaves generally, and the flavor is difficult to eliminate by the common sheet processing, so the tobacco leaves are processed by adopting an air flow line. The common airflow line is treated for 10min at the temperature of 220 ℃ generally, and the temperature is increased, so that the aroma of the tobacco leaves can be negatively influenced. And for C-type tobacco leaves, if the tobacco fragrance is not enough, a choice needs to be made, and the comparison between the embodiment 2 and the embodiment 3 shows that the effect of raising the temperature is obvious for eliminating the strange taste, and the quality of the overall tobacco fragrance of the cigarette leaf group is basically not influenced.

2) The experimental results of example 2 and example 3 show that, because the storage time of the C-type tobacco leaves is long and the cut tobacco rate is high, the moisture of the cut tobacco can be properly relaxed to 13% when the cut tobacco is dried by the airflow line, which is beneficial to the improvement of the cut tobacco yield and the aroma quality.

3) The lipase can catalyze the incompatible acetic acid, lactic acid and the like in the long-term tobacco leaves to be converted into organic acid esters which are positively correlated to the aroma of the cigarettes. The protease can hydrolyze part of protein in tobacco leaves to form free amino acid, and the free amino acid and the newly added carbohydrate are subjected to Maillard flavor production in the tobacco shred baking process, and the sugar-nitrogen ratio of the tobacco leaves is balanced. Beta-glucosidase has some utility for the release of precursor substances for some cigarettes.

4) Comparing example 3 with example 4, in example 4, the type B tobacco leaves are pre-treated and incorporated into the type A tobacco leaves, and the second shred-making feeding is carried out, and sensory evaluation shows that the evaluation result of example 4 is slightly inferior to that of example 3, and the reason for this is that the tobacco leaves are excessively treated to reduce the quality of the tobacco leaves.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, many variations and modifications can be made without departing from the spirit of the invention, which falls within the scope of the invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A processing method of a leaf group formula containing aged tobacco leaves is characterized by comprising the following steps:

step one, establishing a database, and completing sampling and detection of single cigarettes of all grades after the new cigarettes are put into a tobacco strip warehouse and aged for 12 months, wherein detection indexes comprise volatile oil yield, total amount of new phytodiene and phytofuran, the result of the volatile oil yield is set as X0, and the result of the total amount of the new phytodiene and phytofuran is set as Y0;

step two, when single tobacco with the storage year of more than 3 years appears in the leaf group formula, the yield of the volatile oil and the total amount of the new phytodiene and the plant furan are detected again before use, the result of the yield of the volatile oil is named as X1, the result of the total amount of the new phytodiene and the plant furan is named as Y1, and the tobacco leaves are grouped according to the comparison results of X1 and Y1 with X0 and Y0:

A. the method is characterized by comprising the following steps of (1) preprocessing the tobacco leaves B, wherein the preprocessing method comprises the following steps: after moisture regaining and shredding, adding a quality improving preparation B, moving the thin plate threads, drying the thin plate threads until the moisture content is 12-13%, and storing for later use, wherein the thin plate threads are dried at the temperature of 135-145 ℃ for 5-10 min;

B. the pretreatment is carried out on the C-type tobacco leaves, and the pretreatment method comprises the following steps: after moisture regaining and shredding, adding a quality improving agent C, moving to an air flow line, drying until the moisture content is 12-13%, and storing for later use, wherein the air flow line is used for drying the tobacco at 220-290 ℃ for 8-12 s;

C. feeding tobacco leaves A, adding or not adding pretreated tobacco leaves B after moisture regain and shredding, feeding sugar A, feeding a sheet line, and drying until the moisture content is 12-13%;

step four, on the tobacco shred making line, uniformly mixing the puffed tobacco shreds, the cut stems, the tobacco leaves A, the tobacco leaves B and the tobacco leaves C processed in the step three according to the formula proportion of the tobacco shreds, adding fragrance, and entering a tobacco shred storage cabinet to obtain the tobacco shred storage cabinet;

the quality-improving preparation B takes the quality of tobacco leaves as a reference and consists of the following substances: 0.01-0.05% of medlar extract, 0.01-0.05% of Chinese date extract, 0.01-0.05% of dark plum extract, 0.01-0.05% of carob bean extract, 0.005-0.02% of oil of cloth withered leaves, 0.01-0.2% of molasses extract, 0.01-0.05% of laccase, 0.01-0.1% of tobacco extract, 0.001-0.01% of 2-acetyl pyrrole, and propylene glycol and water as solvents;

the quality improving preparation C takes the quality of tobacco leaves as a reference and consists of the following substances: 0.01-0.05% of medlar extract, 0.01-0.05% of jujube extract, 0.01-0.05% of dark plum extract, 0.01-0.05% of carob bean extract, 0.005-0.02% of oil of cloth withered leaves, 0.01-0.2% of molasses extract, 0.01-0.05% of laccase, 0.01-0.1% of tobacco extract, 0.001-0.01% of 2-acetyl pyrrole, 0-0.05% of flavourzyme, 0-0.05% of alkaline protease, 0-0.02% of lipase, 0-0.02% of beta-glucosidase, and propylene glycol and water as solvents;

the sugar material A is prepared by compounding honey, tobacco extract and liquorice extract according to the weight ratio of 5:1:2, and the feeding amount is 2% of the weight of the tobacco leaves.

2. The method of claim 1, wherein the volatile oil yield is determined by simultaneous distillation and extraction, collecting the volatile oil with dichloromethane, and removing solvent by evaporation and concentration.

3. The method of claim 1, wherein the total amount of neophytadiene and phytofurane is determined by GC-MS and quantified by an internal standard method.