CN116918999B

CN116918999B - A processing method for improving the quality of flue-cured tobacco leaves by using Aquilaria sinensis

Info

Publication number: CN116918999B
Application number: CN202210349600.3A
Authority: CN
Inventors: 刘训林
Original assignee: Individual
Current assignee: Individual
Priority date: 2022-04-02
Filing date: 2022-04-02
Publication date: 2025-09-05
Anticipated expiration: 2042-04-02
Also published as: CN116918999A

Abstract

本发明提供了一种利用沉香结香菌提升烤烟叶品质的加工方法，包括如下步骤：S1、利用沉香树酯培养沉香结香复合菌，并分离培养沉香优势结香菌；S2、与新鲜加湿的烤烟叶混合，控制温度为25‑35℃、相对湿度为70‑90％下发酵，待新鲜烤烟叶表面布满菌丝后，将烤烟叶烘干至含水量为10％‑13％；S3、将烟叶进行堆垛至高度100‑120cm，或加湿悬挂，在20‑23℃、相对湿度为60％‑65％下加速醇化5‑7个月。本发明所述利用沉香结香菌提升烤烟叶品质的加工方法首次利用沉香结香复合菌和分离纯化的优势结香菌对烤烟叶进行人工发酵，缩短醇化周期并显著改善烟叶的综合感官评价。The present invention provides a processing method for improving the quality of flue-cured tobacco leaves using agarwood resin esters, comprising the following steps: S1, culturing agarwood resin composite fungi and isolating and culturing agarwood dominant fungi; S2, mixing with fresh, humidified flue-cured tobacco leaves, and fermenting at a controlled temperature of 25-35°C and a relative humidity of 70-90%. After the surface of the fresh flue-cured tobacco leaves is fully covered with mycelium, the flue-cured tobacco leaves are dried to a moisture content of 10%-13%; S3, stacking the tobacco leaves to a height of 100-120 cm, or humidifying and hanging them for accelerated aging at 20-23°C and a relative humidity of 60%-65% for 5-7 months. The processing method for improving the quality of flue-cured tobacco leaves using agarwood resin esters for the first time utilizes agarwood resin composite fungi and isolated and purified dominant fungi to artificially ferment flue-cured tobacco leaves, shortening the aging cycle and significantly improving the comprehensive sensory evaluation of the tobacco leaves.

Description

Processing method for improving quality of flue-cured tobacco leaves by using agilawood and jiesheng bacteria

Technical Field

The invention relates to the technical field of tobacco processing, in particular to a processing method for improving the quality of flue-cured tobacco leaves by using agilawood jieshan.

Background

Tobacco is an important cash crop, and is one of the important sources of national tax. Because the newly harvested tobacco leaves have the defects of heavy green miscellaneous gas, large irritation, rough smoke and the like, in order to improve the quality of the tobacco leaves, the tobacco leaves must be alcoholized. Tobacco mellowing, namely, under the combined action of microorganisms, enzymes and chemical components, tobacco leaves undergo a series of biochemical reactions in the storage process, so that the accumulation of tobacco aroma substances is facilitated, and the quality improvement is promoted.

In consideration of the defects of long natural fermentation time consumption, large occupied area, poor economy and the like, the research on the tobacco mellowing by artificial fermentation is increasing, and the artificial fermentation is usually carried out by using bacillus cereus, bacillus pumilus, bacillus amyloliquefaciens, bacillus similis, bacillus highland, aroma-producing saccharomycetes and the like separated from tobacco leaves or planting soil, and other sources of microorganisms are used for reporting fresh tobacco mellowing quality, and the improvement of the aroma of flue-cured tobacco leaves is not obvious, especially low-grade tobacco leaves.

The agalloch eaglewood is used as the first part of Zhongxiang, the king in the medicine is the wood containing resin of the aquilaria sinensis of daphnaceae, and is mainly distributed in regions such as Vietnam, india, indonesia, malaysia and the like, and researches show that the agalloch eaglewood can reduce the pungent taste of cigarettes and has the throat moistening effect. The Chinese patent publication No. CN109512012A discloses a agilawood tobacco shred which comprises 92-96 wt% of tobacco shred and 4-8 wt% of agilawood tobacco shred, wherein the diameter of the agilawood tobacco shred is 0.8-1mm, the agilawood tobacco shred is spongy, and the agilawood tobacco shred is uniformly mixed in the tobacco shred, and has the advantages of full smoke, average and natural aroma and the like, but the cost is high. How to utilize agilawood to improve tobacco quality becomes a hot spot direction in the biotechnology work of tobacco.

Disclosure of Invention

In view of the above, the present invention aims to provide a processing method for improving the quality of flue-cured tobacco leaves by using agilawood and jieshen, so as to further improve the sensory evaluation of tobacco leaves, especially upper tobacco leaves.

In order to achieve the above purpose, the technical scheme of the invention is realized as follows:

A processing method for improving the quality of flue-cured tobacco leaves by using agilawood and jixiang bacteria comprises the following steps of S1, obtaining agilawood and jixiang compound bacteria by using agilawood resin, separating and culturing agilawood and jixiang bacteria, S2, mixing with fresh and humidified flue-cured tobacco leaves, fermenting at a temperature of 25-35 ℃ and a relative humidity of 70-90%, drying the flue-cured tobacco leaves until the surfaces of the fresh flue-cured tobacco leaves are covered with hypha, and stacking the tobacco leaves to a height of 100-120cm or suspending and humidifying, and accelerating alcoholization for 5-7 months at a temperature of 20-23 ℃ and a relative humidity of 60-65%. The tobacco leaves have the same beneficial effects in fermentation treatment by spraying water for moisturizing after hanging, and detailed description is omitted here.

The agilawood jiesheng bacteria comprise agilawood jiesheng complex bacteria and agilawood dominant jiesheng bacteria, wherein the agilawood dominant jiesheng bacteria are single or combined strains separated from the agilawood jiesheng complex bacteria.

Preferably, the step S1 comprises the steps of S11, taking and cultivating agilawood resin with a fixed or natural fixed fragrance, crushing the agilawood resin into particles with a particle size of 50-200 mu m through a crusher, S12, mixing pretreated tobacco leaves with crushed agilawood resin powder, uniformly mixing the particles with the crushed agilawood resin powder, placing the mixture into a tray, placing the tray into a biochemical box with the temperature of 35 ℃ for cultivation, S13, keeping the temperature of 35+/-0.5 ℃ and the humidity of 75% -90%, standing the tray for 2-3 days in a ventilation environment, and obtaining agilawood-fixed fragrance composite bacteria after agilawood mycelia are fully distributed in the tray, and separating and cultivating agilawood dominant fragrance-forming bacteria.

Preferably, the pretreatment of the tobacco leaves comprises the steps of S121, removing stems and impurities of the tobacco leaves, balancing for 48 hours at the temperature of 22+/-2 ℃ and the relative humidity of 55-60%, then measuring the water content, S122, rolling and extruding wet tobacco bases to enable juice of the tobacco leaves to overflow, and treating for 3-5min through a microwave generator.

Preferably, the tobacco leaves are upper tobacco leaves, including upper two greenhouse leaves and/or top leaves.

Preferably, the agilawood dominant note fungus isolated from the agilawood note combination fungus comprises endophytic fungi and endophytic bacteria, preferably at least one of the genera rhodosporidium (Lasiodiplodia) fungus, sclerotium (Rigidoporus) fungus, mao Shuang spore (Lasiodiplodia sp.) fungus, fusarium (Fusarium) fungus, black fungus (Melanotus flavolivens), cephalosporin (Cephalosporium sp.), hypocrea jecorina (Hypocrea jecorina), monospora (Pelomonas) and actinomyces (Actinomycetospora).

Preferably, the agilawood dominant jiesheng bacteria consist of Fusarium (Fusarium) bacteria and black fungus (Melanotus flavolivens) according to a ratio of 1-5:1-5.

Preferably, the step S2 comprises spraying the dominant jiesheng fungus liquid or fermentation liquid of agilawood on the surface of flue-cured tobacco leaves according to a ratio of 0.5-1:1 (W/W), stacking to a height of 80-100cm or humidifying and suspending, controlling the temperature to 25-28 ℃ and the relative humidity to 90-95% for fermenting for 2-3 days, turning the stack after the temperature of the stacked core is raised to 35-38 ℃, controlling the temperature to 28-32 ℃ and the relative humidity to 80-85% for fermenting for 3-4 days, and drying the flue-cured tobacco leaves until the surface of the fresh flue-cured tobacco leaves is full of hyphae and the moisture content of the flue-cured tobacco leaves is 10% -13%. The humidifying hanging operation is the prior art and will not be described here in detail.

The preparation method of the agilawood dominant jiesheng fungus liquid comprises the following steps of S21 inoculating an inclined plane strain of agilawood dominant jiesheng fungus into a sterilized seed culture medium, performing constant-temperature shake culture for 36 hours at 160-180rpm and 30-32 ℃ to obtain a seed culture liquid, S22 centrifuging the seed culture liquid at 6500-8000rpm for 15-20min, discarding clear liquid, mixing different types of fungus mud according to a proportion, and adding deionized water to prepare 5-10% mixed fungus liquid.

Preferably, the seed culture medium contains 20.0g glucose, 200.0g potato, distilled water, natural pH, and sterilizing at 121deg.C for 20min.

Preferably, the agilawood dominant aroma-forming bacteria fermentation liquor is prepared by filling 40% (v/v) liquid culture medium into a fermentation tank, inoculating sclerotium seed liquor into the fermentation tank according to an inoculum size of 6%, controlling a ventilation ratio to be 1:1.2, stirring at a rotation speed of 80rpm and a culture temperature of 32 ℃, culturing for 16 hours, inoculating yellow green black fungus seed liquor according to an inoculum size of 5-10%, continuously culturing for 12 hours at a stirring rotation speed of 130rpm and a temperature of 35 ℃, and then supplementing 25% (v/v) second liquid culture medium, and continuously culturing for 42 hours to obtain the fermentation liquor.

Preferably, the liquid culture medium comprises 3g of sodium nitrate, 1g of disodium hydrogen phosphate, 20g of potato extract powder, 1.5g of sodium chloride, 30g of quinoa flour, 30g of glucose, adding distilled water to 1000ml, autoclaving at 121 ℃ for 20min, and adjusting pH to 6.2-6.8, and the second liquid culture medium comprises 6g of potato extract powder, 20g of glucose, 50g of flue-cured tobacco leaf powder, 0.1g of glucose and 1000ml of distilled water, autoclaving at 121 ℃ for 20min and pH to 7.2-7.6.

Compared with the prior art, the processing method for improving the quality of the tobacco leaves has the following advantages:

the processing method for improving the quality of the tobacco leaves comprises the steps of (1) alcoholizing the tobacco leaves by using agilawood combined bacteria or agilawood dominant combined bacteria to improve the sensory evaluation of the tobacco leaves, especially the upper tobacco leaves, (2) screening the agilawood combined bacteria or agilawood dominant combined bacteria by using the upper tobacco leaves to improve the selection pressure, and obtaining a synergistic combination to improve the alcoholization effect, (3) carrying out mixed fermentation on the agilawood dominant combined bacteria, adding a second liquid culture solution in the fermentation culture to promote the generation of resolvers, and realizing the maximization of the synergistic effect, (4) controlling alcoholization fermentation parameters to enable the agilawood combined bacteria or agilawood dominant combined bacteria to play a role, finally producing a large amount of aromatic substances and stress substances trehalose in stages, and having good comprehensive sensory evaluation.

Detailed Description

It should be noted that, without conflict, the embodiments of the present application and features of the embodiments may be combined with each other. The data in the examples are obtained by the inventors through numerous experiments, only a part of which is shown in the specification, and those skilled in the art can understand and practice the present application under the data. These examples are only for illustrating the present application and are not intended to limit the scope of the present application. The present application will be described in detail with reference to examples. The tobacco leaves are tobacco leaves subjected to primary baking, threshing and redrying, and are upper tobacco leaves comprising upper two greenhouse leaves and top leaves, and are provided by Jiangsu Zhongyan industry Limited liability company.

Tobacco mellowing, also called tobacco fermentation, is an important processing unit in the tobacco processing process. The tobacco mellowing substance is a processing process of deeply changing physical and chemical properties of tobacco under certain temperature and humidity conditions, and obviously improving the fragrance, color and taste quality of the tobacco, and the tobacco mellowing is divided into natural mellowing and artificial mellowing, and the process is generally considered to degrade macromolecular substances such as polysaccharide, protein and the like in the tobacco to generate aromatic micromolecular substances such as esters, acids and the like through metabolic activities of a large number of microbial colonies, so that the smoking quality of the tobacco is effectively improved and the mellowing time is shortened.

In the prior art, food microorganisms such as lactobacillus, lactobacillus and rhizopus are used for alcoholizing tobacco leaves except microorganisms separated from the tobacco leaves, but the proportion of various components in the tobacco leaves after alcoholizing is not consistent, and the effects of flavoring and improving the quality of the tobacco leaves are not ideal. The endophyte strain in the agilawood resin is cultured to absorb monosaccharide disaccharide in tobacco leaves and decompose macromolecular organic nutrient sources such as starch, trehalose is produced by stress or metabolism to improve tobacco leaf matrine, and various aromatic substances form the fragrance of the agilawood resin, so that the fragrance is pleasant, and the use of the agilawood jieshan bacteria for alcoholizing the tobacco leaves has important significance.

Example 1 obtaining of agilawood and aroma complex bacteria

The invention provides agilawood and aroma compound bacteria for tobacco leaf treatment, which are obtained by the following steps:

S1, taking agalloch eaglewood resin for cultivating and forming aroma or natural aroma, and crushing the agalloch eaglewood resin into 50 mu m of particle size by a crusher;

s2, mixing the pretreated tobacco leaves with the crushed agilawood resin powder, uniformly mixing, placing the mixture into a tray, and placing the tray into a biochemical box at 35 ℃ for culturing;

s3, keeping the temperature at 35+/-0.5 ℃ and the humidity at 75%, standing for 2-3 days in a ventilation environment, and then obtaining the agilawood and agilawood compound bacteria after the agilawood hyphae are fully distributed.

The agilawood resin used in the embodiment of the application is obtained from wild agilawood chips collected and stored in a certain traditional Chinese medicine shop, and is identified as aquilaria sinensis tree. The agilawood and edgeworthia complex bacteria disclosed by the application are complex strains formed after endophytic fungi of agilawood resin grow and reproduce by taking tea leaves as nutrients.

Preferably, the pretreatment of the tobacco leaves in the step S2 comprises removing stems and impurities of the tobacco leaves, balancing for 48 hours under the conditions of (22+/-2) DEG C and relative humidity of 60%, then measuring the water content, and S22, rolling and extruding wet tobacco leaves to enable juice of the tobacco leaves to overflow, and treating for 3-5min through a microwave generator. The microwave sterilization is utilized, the treatment time is short, the damage of tobacco components is less, the tobacco mellowing environment is simulated, and the screened dominant aroma-forming bacteria are good in effect. Preferably, the power of the microwave generator is 800W, and the operating frequency is 2450MHz.

Preferably, the tobacco leaves used for screening are upper tobacco leaves, comprising upper two greenhouse leaves and top leaves. Compared with the middle tobacco leaf, the upper tobacco leaf has thick leaf, compact structure, insufficient maturity, too high macromolecular content such as protein and nicotine content, too low reducing sugar content and sugar-alkali ratio, large tobacco mellowing difficulty and poor final quality, and can improve screening pressure.

Example 2 obtaining of agilawood dominant aroma bacteria

S11, respectively picking hyphae obtained in the step S3 by using an inoculating loop, putting the hyphae into 100ml of sterile water, and shake-culturing the hyphae for 20min at a constant temperature of 37 ℃ and a shaking table at 120 rpm;

s12, coating 200 μl of liquid on a screening plate, culturing for 3-5d at a constant temperature of 32 ℃, picking single colony with obvious hydrolysis circle, observing colony morphology, simultaneously gram staining the strain, and observing morphological characteristics of the thallus under an optical microscope;

S13, extracting DNA of each strain by adopting a water boiling method, carrying out PCR amplification, then sending to a biological engineering (Shanghai) stock company for sequencing, carrying out homology comparison of the strains in an NCBI gene library, constructing a phylogenetic tree, identifying the strains by combining morphological observation, gram staining results and 16SrDNA sequencing results, the obtained agilawood dominant aroma bacteria comprise endophytic fungi and endophytic bacteria, preferably selected from Saccharomyces (Lasiodiplodia), saccharomyces Mao Shuang (Lasiodiplodia sp.), tremella flavescens (Cephalosporium sp.), fusarium (Fusarium), tremella flavescens (Melanotus flavolivens), cephalosporium (Cephalosporium sp.), hymenoxenia rubra (Hypocrea jecorina), monascus (Pelomonas) and Actinobacillus (Actinomycetospora).

The agilawood dominant aroma bacteria are used for flue-cured tobacco She Chunhua, and can enable tobacco leaves to have different fragrances, such as Fusarium (Fusarium) bacteria, black fungus (Melanotus flavolivens) and actinomycetes (Actinomycetospora) which take the fragrance of nectar as a main factor, sclerotium (Rigidoporus) bacteria, mao Shuang spore (Lasiodiplodia sp.), cephamus (Cephalosporium sp.) and russet fungus (Hypocrea jecorina) which take the fragrance of fruit milk as a main factor, and monospora (Pelomonas) and chromatophora (Lasiodiplodia) which take the fragrance of tricholoma matsutake as a main factor.

S14, preparation of seed liquid

Drying the upper tobacco leaf from the top, grinding into tobacco powder, sieving with a 40 mesh sieve, weighing 2g tobacco powder, adding into 500mL triangular flask, adding 200mL water, sterilizing at 121deg.C for 20min, and cooling. Adding 10mL of sterile water into a bevel test tube by using a pipetting gun, repeatedly blowing and sucking to disperse each strain or spore in the sterile water, sucking a certain amount of bacterial suspension, inoculating into a seed culture medium, and shaking and fermenting for 2 days at 150r/min and 30 ℃ for later use, wherein the initial bacterial concentration is 10 ⁷/mL.

S15, strain screening

After preliminary screening, 50g of the upper tobacco leaves after being crushed (sieved by a 40-mesh sieve) are weighed, placed in a tray, sprayed with a proper amount of sterile water, and subjected to constant temperature culture for 4d at 35 ℃ in a biochemical incubator according to seed liquid prepared in the step S14 in Table 1, so that the tobacco leaves are enabled to have 25% of water content, the conventional chemical component content of the tobacco leaves is analyzed, and sensory evaluation is carried out after tobacco cut rolls are made into cigarettes, wherein the results are shown in Table 1.

The conventional chemical component detection adopts YC/Y160-2002 continuous flow method for measuring total plant alkaloids of tobacco and tobacco products, the nicotine content is measured by adopting a 3, 5-dinitrosalicylic acid colorimetric method, the total sugar and reducing sugar content is measured by adopting a gas chromatograph-mass spectrometer, and the specific measuring method is the prior art and is not repeated here.

The sensory evaluation method for each treatment group of tobacco leaves is carried out by referring to the three-point test method in the tobacco industry standard YCT 138-1998 sensory evaluation method for tobacco and tobacco products. Untreated tobacco cut filler was used as a blank for each sample, two blanks, and one sample. Samples were scored by differences in the evaluation. The sensory quality index involved in the evaluation is aroma quality, aroma quantity, miscellaneous gas, strength, irritation and aftertaste. Each quality index (full score: 10 score) was scored and finally summarized by comparison. The scoring is described as higher impurity gas fraction, lower impurity gas, higher stiffness fraction, lower stiffness, and higher irritation fraction, lower irritation (nasal, throat).

TABLE 1 influence of different bacterial species on conventional component content and sensory evaluation of tobacco leaves

Researches show that the starch content in tobacco leaves after topping is rapidly increased, the starch content is gradually reduced in the ripening process, the water-soluble sugar content is increased, the substance content of the tobacco leaves can obviously influence the quality of the tobacco leaves, if the starch content is higher, the combustion speed and completeness are influenced, burnt smell is generated, and small molecular substances such as reducing sugar generated by starch and the like are degraded, so that the tobacco leaves are important substance bases of burnt sweet fragrance, can balance the acid and alkali smell, can promote the generation of Maillard reaction products under certain conditions, reduce the irritation of smoke and are beneficial to the taste and fragrance of the smoke.

As shown in Table 1, the strains separated and screened by the tobacco-containing culture medium can grow and reproduce by taking sugar in tobacco as a carbon source and produce aromatic substances, and the trichosanthes has the capacity of degrading part of nicotine and has stronger aroma-producing capacity. When different species are mixed fermented, the result is usually a simple superposition of the fermentation results, e.g. groups 6-8, and even antagonism, e.g. groups 5, 10. The applicant has found unexpectedly that the total sugar content of tobacco leaves when fusarium is mixed with fusarium aureobasidium = 1:1 is lower, the quantity of the generated aromatic substances is obviously higher than that of the fusarium aureobasidium = 1:1, the final faint scent and nectar scent are obvious in characteristics, and the sensory evaluation is excellent, so that the fusarium aureobasidium = 1:1 has a synergistic effect. At the same time, the reducing sugar content is obviously increased compared with other groups, and the detection analysis shows that a large amount of trehalose is generated in the mixed fermentation process.

Example 3

A processing method for improving the quality of flue-cured tobacco leaves by using agilawood and jie-xiang compound bacteria comprises the following steps:

s1, taking agalloch eaglewood resin for cultivating and forming aroma or natural aroma, and crushing the agalloch eaglewood resin into particles with the particle size of 50-200 mu m by a crusher;

S2, mixing the processed tobacco leaves with the crushed agilawood resin powder, uniformly mixing, placing the mixture into a tray, and placing the tray into a biochemical box at 35 ℃ for culturing;

S3, keeping the temperature at 35+/-0.5 ℃ and the relative humidity at 75% -90%, standing for 2-3 days in a ventilation environment, and after the agilawood hyphae are fully distributed in the environment, obtaining agilawood complex bacteria, drying at 40 ℃ and crushing into 100-mesh fine powder for later use;

S4, mixing 1000g of agilawood and jiesheng compound bacteria fine powder obtained in the step S3 with fresh and humidified flue-cured tobacco leaves according to the ratio of 3-10g to 1000g, controlling the temperature to be 25-35 ℃ and the relative humidity to be 90% and fermenting for 5-7 days, and drying the flue-cured tobacco leaves until the surfaces of the fresh flue-cured tobacco leaves are covered with hypha, wherein the moisture content of the flue-cured tobacco leaves is 10% -13%.

S5, stacking tobacco leaves to the height of 100-120cm, and accelerating alcoholization for 6 months at the temperature of 20-23 ℃ and the relative humidity of 60-65%.

Example 4

A processing method for improving the quality of flue-cured tobacco leaves by utilizing agilawood dominant jiesheng bacteria comprises the following steps:

S1, respectively inoculating slant strains of fusarium and black fungus into a sterilized seed culture medium, and performing constant-temperature shake culture for 36 hours at 160rpm and 30 ℃ to obtain a seed culture solution;

The seed culture medium contains glucose 20.0g, potato 200.0g, distilled water, natural pH, and sterilizing at 121deg.C for 20min.

S2, centrifuging the bacterial seed solution at 6500rpm for 15min, discarding clear liquid, mixing bacterial sludge of Fusarium and black fungus at a ratio of 1:1 (W/W), and adding deionized water to prepare 5% mixed bacterial solution;

s3, spraying the mixed bacterial liquid on the surface of the flue-cured tobacco leaves according to a ratio of 1:1 (W/W), fermenting for 5-7 days at the temperature of 25-35 ℃ and the relative humidity of 90%, and after hypha is fully distributed on the surface of the fresh flue-cured tobacco leaves, drying the flue-cured tobacco leaves until the water content is 10-13%, wherein no obvious water drops are formed on the surface of the tobacco leaves.

S4, stacking tobacco leaves to the height of 100-120cm, and accelerating alcoholization for 6 months at the temperature of 20-23 ℃ and the relative humidity of 60-65%.

Example 5

S2, filling 40% (v/v) liquid culture medium into a fermentation tank, inoculating fusarium seed liquid into the fermentation tank according to an inoculation amount of 6%, controlling the aeration ratio to be 1:1.2, controlling the stirring rotation speed to be 80rpm, culturing at 32 ℃ for 16 hours, inoculating yellow-green black fungus seed liquid according to an inoculation amount of 5-10%, continuously culturing for 12 hours at the aeration ratio of 1:1.7, and then adding 25% (v/v) second liquid culture medium, and continuously culturing for 42 hours to obtain fermentation liquor.

The liquid culture medium comprises 3g of sodium nitrate, 1g of disodium hydrogen phosphate, 20g of potato extract powder, 1.5g of sodium chloride, 30g of quinoa flour, 30g of glucose, adding distilled water to 1000ml, sterilizing at 121 ℃ for 20min under high pressure, and adjusting the pH to 6.2-6.8;

the second liquid culture medium comprises potato extract powder 6g, glucose 20g, flue-cured tobacco leaf powder 50g, and glucose hexasaccharide 0.1g, distilled water 1000ml, and sterilizing at 121deg.C under high pressure for 20min at pH7.2-7.6;

s3, adding water into the fermentation liquor to dilute the fermentation liquor to 5% of mixed bacterial liquor, spraying the mixed bacterial liquor on the surface of the flue-cured tobacco leaves according to a ratio of 1:1 (W/W), controlling the temperature to be 25-35 ℃ and fermenting the mixture for 5-7 days under the condition that the relative humidity is 90%, and after hypha is fully distributed on the surface of fresh flue-cured tobacco leaves, drying the flue-cured tobacco leaves until the water content is 10-13% and no obvious water drops are formed on the surface of the tobacco leaves.

Example 6

S3, adding water into the fermentation liquor to dilute the fermentation liquor to 5% of mixed bacterial liquid, spraying the mixed bacterial liquid on the surface of the flue-cured tobacco leaves according to the ratio of 1:1 (W/W), stacking the flue-cured tobacco leaves to the height of 80-100cm, controlling the temperature to 25-28 ℃ and the relative humidity to 90-95% for fermentation for 2-3 days, turning the stack after the temperature of the stack core is raised to 35-38 ℃, controlling the temperature to 28-32 ℃ and the relative humidity to 80-85% for fermentation for 3 days, and drying the flue-cured tobacco leaves until the surface of the fresh flue-cured tobacco leaves is full of hypha, wherein the water content of the flue-cured tobacco leaves is 10-13%, and no obvious water drops are formed on the surface of the tobacco leaves.

Comparative example 1

Tobacco leaf alcoholization treatment by the method of example 1 of publication No. CN111657536A, comparative example 2

The same procedure as in example 6 was followed except that the second liquid culture was not supplemented in step S2;

Comparative example 3

The same method as in example 6 is adopted, except that in the step S2, the liquid culture medium, 3g of sodium nitrate, 1g of dipotassium hydrogen phosphate, 20g of potato extract powder, 1.5g of potassium chloride, 30g of quinoa powder and 30g of glucose are added, distilled water is added to 1000ml, the temperature is 121 ℃ and the pressure sterilization is carried out for 20min, and the pH is regulated by sodium hydroxide or nitric acid to 6.2-6.8;

The cured tobacco leaves prepared in each example and comparative example are dried and crushed, and the content change of macromolecular compounds in the tobacco leaves before and after fermentation is measured. The starch content in tobacco leaves is measured by adopting an iodine color development method, the cellulose content is measured by adopting a method such as An Yumin, the trehalose is measured by adopting a trehalose content measuring kit (Soy Bao technology Co., ltd.), YC/T162-2011 (continuous flow method for measuring chlorine in tobacco and tobacco products) and YC/T173-2003 (flame photometry for measuring potassium in tobacco products of tobacco machines), the potassium and chlorine are measured, the aroma substance content is measured by adopting a gas chromatography-mass spectrometer, the specific detection method is the prior art, and the repeated description is omitted herein, and the result is shown in Table 2.

TABLE 2 variation of macromolecular Compound content in tobacco leaves of different groups

Through detection, the contents of starch, cellulose, trehalose, potassium and chlorine in the tobacco to be tested are respectively 10.82%, 14.08%, 1.05 mug/mg, 1.71% and 0.62%, macromolecular compounds such as starch in the tobacco to be tested are degraded into micromolecular substances such as monosaccharide through the metabolic activity of microorganisms, and meanwhile, more trehalose can be generated to harmonize the bitter taste of nicotine through strain compound fermentation, so that the tobacco is sweet and moist, and the burning and sucking quality is improved. From the above table, the method of embodiment 3 uses the agilawood resin to obtain agilawood and aroma composite bacteria to carry out alcoholization fermentation on tobacco leaves, so that the starch content can be reduced, and the burning and sucking quality of the tobacco leaves can be improved; in the embodiment 4-5, the separated agilawood dominant bacteria, namely fusarium and black fungus are subjected to mixed fermentation, obvious synergistic effect exists between the fusarium and the black fungus, and the strain reaction is generated by optimizing the mixed fermentation process to further increase the trehalose content;

the cured tobacco shreds prepared in each example/comparative example were rolled into cigarettes, and sensory evaluation was performed by the method of example 3, and the results are shown in table 3.

TABLE 3 sensory evaluation results of tobacco leaves prepared in different groups

The final tobacco leaf was good in sensory evaluation by improving the alcoholization effect by promoting the metabolic activity of microorganisms although the potassium-chlorine ratio of the final tobacco leaf was reduced by adding the second liquid medium containing no potassium as compared with comparative example 3. As can be seen from Table 3, the overall sensory quality evaluation of the cured tobacco leaves prepared in examples 3 to 5 was superior to that of comparative example 1. In example 6, mixed fermentation of fusarium and black fungus is utilized, a large amount of enzymes are generated in the later period of fermentation, after the mixed fermentation is inoculated to the redried tobacco, the enzymes are firstly used for carrying out primary degradation on the tobacco, and solid fermentation of the redried tobacco is carried out by controlling the environmental parameters of fermentation in stages and respectively reaching the optimal metabolic conditions of the fusarium and the black fungus, so that the sensory evaluation of the prepared tobacco is excellent.

The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, alternatives, and improvements that fall within the spirit and scope of the invention.

Claims

1. A processing method for improving the quality of flue-cured tobacco leaves by using agilawood and jiesheng is characterized by comprising the following steps:

S1, obtaining agilawood and aroma complex bacteria by using agilawood resin, and separating and culturing agilawood dominant aroma complex bacteria, wherein the agilawood dominant aroma complex bacteria consist of Fusarium (Fusarium) and black fungus (Melanotus flavolivens) according to a ratio of 1-5:1-5;

The step S1 comprises the following steps:

s11, taking agalloch eaglewood resin for cultivating and forming the incense or natural incense, and crushing the agalloch eaglewood resin into particles with the particle size of 50-200 mu m by a crusher;

s12, mixing the pretreated tobacco leaves with the crushed agilawood resin powder, uniformly mixing, placing the mixture into a tray, and placing the tray into a 30-35 ℃ biochemical box for culturing;

S13, keeping the temperature at 35+/-0.5 ℃ and the humidity at 75% -90%, standing for 2-3 days in a ventilation environment, and after the agilawood hyphae are fully distributed in the environment, obtaining agilawood and aroma complex bacteria, and separating and culturing agilawood dominant aroma complex bacteria;

S2, mixing the agilawood dominant aroma bacteria with fresh humidified flue-cured tobacco leaves, fermenting at the temperature of 25-35 ℃ and the relative humidity of 70-90%, and drying the flue-cured tobacco leaves until the surfaces of the fresh flue-cured tobacco leaves are covered with hypha, wherein the water content of the flue-cured tobacco leaves is 10% -13%;

S3, stacking tobacco leaves to the height of 100-120cm, or hanging and humidifying, and accelerating alcoholization for 5-7 months at the temperature of 20-23 ℃ and the relative humidity of 60% -65%.

2. The method for improving the quality of flue-cured tobacco leaves by using agilawood and jieshen, according to claim 1, wherein the pretreatment of tobacco leaves is as follows:

S121, removing stems and impurities of tobacco leaves, balancing for 48 hours at the temperature of 22+/-2 ℃ and the relative humidity of 55-60%, and then measuring the water content;

s122, rolling and squeezing the tobacco leaf wet base to enable juice of the tobacco leaf to overflow, and processing the tobacco leaf by a microwave generator for 3-5min.

3. The method for improving the quality of tobacco leaves by using agilawood, according to claim 2, wherein the tobacco leaves are upper tobacco leaves and comprise upper two greenhouse leaves and/or top leaves.

4. The method for improving the quality of flue-cured tobacco leaves by using agilawood jieshizoma as claimed in claim 1, wherein the steps S2 and S3 comprise spraying agilawood jieshizoma liquid onto the surfaces of the flue-cured tobacco leaves according to a ratio of 0.5-1:1 (W/W), stacking to a height of 80-100cm, or humidifying and suspending, controlling the temperature to 25-28 ℃ and the relative humidity to 90-95% for 2-3 days, turning piles after the temperature of a pile core is raised to 35-38 ℃, controlling the temperature to 28-32 ℃ and the relative humidity to 80-85% for 3-4 days, and drying the flue-cured tobacco leaves until the surfaces of the fresh flue-cured tobacco leaves are full of hyphae and the moisture content of 10% -13%.

5. The processing method for improving the quality of flue-cured tobacco leaves by using agilawood and jiesheng bacteria according to claim 4, wherein the agilawood dominant jiesheng bacteria liquid is prepared by the following steps:

S21, inoculating the inclined plane strain of the agilawood dominant jiesheng fungus into a sterilized seed culture medium, and performing constant-temperature shake culture for 36-40h at 160-180rpm and 30-32 ℃ to obtain a seed culture solution;

S22, placing the seed culture solution in 6500-8000rpm for centrifugation for 15-20min, discarding the clear solution, mixing different bacterial sludge according to a certain proportion, and adding deionized water to prepare 5-10% mixed bacterial solution.

6. The method for improving the quality of flue-cured tobacco leaves by using agalloch eaglewood, as claimed in claim 5, wherein each 1L of the seed culture medium contains 20.0g of glucose, 200.0g of potato, the balance of distilled water, and has a natural pH value of 121 ℃ for sterilization for 20min.