CN115088861B - Method for preparing tobacco leaf extract by using waste tobacco leaves/tobacco powder - Google Patents

Abstract

The invention discloses a method for preparing tobacco leaf extract by using waste tobacco leaves/tobacco powder, which includes: liquefying the waste tobacco leaves/tobacco powder with near-critical water, adding the waste tobacco leaf/tobacco powder sample and distilled water into a reaction kettle according to a preset ratio, and sealing Reaction kettle, heat the reaction kettle to the target temperature according to the preset heating rate. After the preset time of insulation, it is naturally cooled to room temperature. The material is discharged and filtered or centrifuged to obtain the solid phase and liquid phase. At the same time, the gas generated during the reaction is collected. ; To analyze the components of waste tobacco leaves/tobacco powder extract, the obtained solid phase residue is extracted with an organic solvent and filtered. The filter residue is washed and dried to a constant weight. After the filtrate is concentrated and extracted, GC‑MS is used to analyze the waste tobacco leaves/tobacco powder extraction. composition of matter. The method of the present invention utilizes waste tobacco leaves/tobacco powder to prepare tobacco leaf extract. It utilizes near-critical water technology and only uses waste tobacco leaves/tobacco powder and water as raw materials to prepare the waste tobacco leaf/tobacco powder extract.

Description

Method for preparing tobacco leaf extract using waste tobacco leaves/tobacco powder

Technical field

The present invention relates to the technical field of tobacco processing, and in particular to a method for preparing tobacco leaf extract by utilizing waste tobacco leaves/tobacco dust.

Background technique

In recent years, my country's tobacco production has been huge. The average tobacco production from 2015 to 2019 was about 2.4 million tons. A large amount of discarded tobacco leaves such as tobacco trimmings, tobacco powder and low-quality inventory tobacco leaves are produced every year. Waste tobacco leaves are rich in lignin, cellulose and other organic matter and are very good biomass resources. At present, the utilization rate of discarded tobacco leaves is low, which is not only a waste of resources, but also causes pollution to the environment if not handled properly.

In recent years, there has been a lot of research on the utilization of waste biological resources, mainly focusing on the following aspects: First, the preparation of tobacco sheets, using waste tobacco leaves/tobacco powder, tobacco powder, tobacco flakes and other wastes, through roller pressing method, thick pulp method, paper making Methods and others prepare tobacco flakes. Tobacco flakes also play an important role in reducing the tar content of cigarettes, reducing the harm of cigarettes, and improving the quality of cigarettes. However, the waste tobacco leaves/tobacco powder used to prepare tobacco flakes are very limited, and most of them are discarded. . Second, microbial fermentation. Waste tobacco leaves/tobacco powder not only contain rich carbon and nitrogen sources such as sugars and proteins, but also have a loose structure, which is an ideal microbial solid fermentation bed. Therefore, many experts and scholars have studied different types of Application of microorganisms in solid fermentation beds of waste tobacco leaves/tobacco powder. Direct fermentation of waste tobacco leaves/tobacco powder is difficult to completely eliminate pathogenic microorganisms and nicotine, and the volatile components in waste tobacco leaves/tobacco powder are not conducive to microbial fermentation. Third, the extraction of natural ingredients mainly includes the extraction of nicotine, solanesol, plant protein and pectin through extraction technology using waste tobacco leaves/tobacco powder as raw materials. The current technology for extracting nicotine from tobacco leaves or waste tobacco leaves/tobacco powder is It is cumbersome and difficult to produce; the extraction of solanesol requires the use of organic solvents. After obtaining the crude product, it must be purified by methods such as dewaxing, saponification, crystallization and recrystallization. The operation is cumbersome, the cost is high, and it is difficult to industrialize production; Extracting plant protein requires acidification and then extracting plant protein from the solid phase part, which is cumbersome and pollutes the environment. Pectin can be extracted by boiling water extraction, acid hydrolysis, microbial method (enzyme separation method) and ion exchange resin method, but the current extraction efficiency is not high and purification is difficult. In short, it is difficult to achieve large-scale production by isolating specific chemical components from tobacco leaves, and the extraction and preparation process of these compounds requires the use of a large amount of organic solvents, which is time-consuming and labor-intensive, causing secondary pollution to the environment. At the same time, the solid phase after extraction Some of them have not been further processed and utilized, resulting in a waste of resources.

Therefore, there is an urgent need for a method for preparing tobacco leaf extract using waste tobacco leaves/tobacco powder.

Contents of the invention

The object of the present invention is to provide a method for preparing tobacco leaf extract by using waste tobacco leaves/tobacco powder to solve the above-mentioned problems in the prior art. It can only use waste tobacco leaves/tobacco powder and water as raw materials to prepare waste tobacco leaves/tobacco powder. Extract.

The invention provides a method for preparing tobacco leaf extract using waste tobacco leaves/tobacco powder, which includes:

Near-critical water liquefies waste tobacco leaves/tobacco powder, add waste tobacco leaves/tobacco powder samples and distilled water into the reaction kettle according to the preset ratio, close the reaction kettle, heat the reaction kettle to the target temperature according to the preset heating rate, and keep it warm for the preset time. , naturally cool to room temperature, discharge, filter or centrifuge to obtain the solid phase and liquid phase, and collect the gas generated during the reaction;

To analyze the components of waste tobacco leaves/tobacco powder extract, the obtained solid phase residue is extracted with an organic solvent and filtered. The filter residue is washed and dried to a constant weight. After the filtrate is concentrated and extracted, GC-MS is used to analyze the waste tobacco leaves/tobacco powder extract. ingredients.

The method for preparing tobacco leaf extract using waste tobacco leaves/tobacco powder as described above, wherein, preferably, in the step of liquefying the waste tobacco leaves/tobacco powder with near-critical water, the mixing ratio of the waste tobacco leaf/tobacco powder sample and distilled water is 1:2-1:20.

The method for preparing tobacco leaf extract using waste tobacco leaves/tobacco powder as described above, wherein, preferably, in the step of liquefying the waste tobacco leaves/tobacco powder with near-critical water, the waste tobacco leaves/tobacco powder sample and distilled water are mixed in a predetermined amount. After adding the proportion into the reaction kettle, the total volume of the material accounts for 1:3-3:4 of the volume of the reaction kettle.

The method for preparing tobacco leaf extract using waste tobacco leaves/tobacco powder as described above, wherein, preferably, in the step of liquefying waste tobacco leaves/tobacco powder with near-critical water, the temperature rise rate of the reaction kettle is 8°C/min- 15℃/min.

The above method for preparing tobacco leaf extract from waste tobacco leaves/tobacco powder, wherein, preferably, in the step of liquefying waste tobacco leaves/tobacco powder with near-critical water, the target temperature of the reaction kettle is 160°C-260°C , the vapor pressure corresponding to the target temperature is 0.5MPa-6.0MPa, and the holding time at the target temperature is 5min-20min.

The method for preparing tobacco leaf extract using waste tobacco leaves/tobacco powder as described above, wherein, preferably, in the step of liquefying the waste tobacco leaves/tobacco powder with near-critical water, after the preset time of heat preservation, the controller is turned off to heat Switch to allow natural cooling to room temperature.

The method for preparing tobacco leaf extract using waste tobacco leaves/tobacco powder as described above, wherein, preferably, in the step of liquefying the waste tobacco leaves/tobacco powder with near-critical water, the gas generated during the reaction is collected, including :

The gas generated during the reaction is collected through a gas sampling bag connected to the needle valve on the lid of the reaction kettle, and the gas sampling bag is weighed on an electronic balance before and after collecting the gas, and the mass is recorded as m ₀ (Kg) and m ₁ (Kg), use the difference subtraction method to obtain the gas yield,

m _gas =m ₁ -m ₀ (1)

Among them, M represents the mass (Kg) of waste tobacco leaves/tobacco powder raw materials.

The method for preparing tobacco leaf extract using waste tobacco leaves/tobacco powder as mentioned above, wherein, preferably, in the step of analyzing the components of the waste tobacco leaf/tobacco powder extract, the time for organic solvent extraction of the solid phase residue is 2h-12h.

The method for preparing tobacco leaf extract using waste tobacco leaves/tobacco powder as described above, wherein, preferably, in the step of analyzing the components of the waste tobacco leaf/tobacco powder extract, after the filter residue is washed and dried to a constant weight, Calculate residue rate and conversion rate,

Among them, M represents the mass of waste tobacco leaves/tobacco powder raw materials (Kg), and m _residue represents the mass of solid phase residue after drying (Kg).

The method for preparing tobacco leaf extract using waste tobacco leaves/tobacco powder as described above, wherein, preferably, in the step of analyzing the components of the waste tobacco leaf/tobacco powder extract, the filtrate is concentrated by a rotary evaporator and then passed through acetic acid. Ethyl ester, chloroform, and n-hexane were used for extraction, and GC-MS was used to analyze the components of the waste tobacco leaves/tobacco powder extracts obtained by different processing methods.

The extracts obtained by n-hexane extraction include alkanes, alcohols and benzene, the extracts obtained by ethyl acetate extraction include esters, phenols and alcohols, and the extracts obtained by chloroform extraction include pyrazines. Heterocyclic compounds, phenols and aldehydes and ketones.

The invention provides a method for preparing tobacco leaf extract by using waste tobacco leaves/tobacco powder, using near-critical water technology, without using any organic reagents, catalysts, etc., only using waste tobacco leaves/tobacco powder and water as raw materials, and having acid catalysis in itself. Under the conditions of alkali and alkali catalysis, waste tobacco leaves/tobacco powder extracts are prepared to realize the conversion of low economic value waste tobacco leaves/tobacco powder into high value-added tobacco leaf extracts; the method used in the present invention has simple conditions and low reaction consumption. It takes a short time, consumes less energy, has no secondary pollution in the synthesis process, and is green and environmentally friendly; the waste tobacco leaf/tobacco dust extract prepared by the present invention effectively realizes the reuse of waste tobacco leaf/tobacco dust resources and provides a waste tobacco leaf/tobacco dust extract. The conversion path of end resources; the waste tobacco leaf/tobacco powder extract prepared by this method contains nicotine, nicotine degradation products, esters, phenols and other substances, contains more aroma substances, and can be used in tobacco products and other new Flavoring additives for tobacco products such as heat-not-burn cigarettes, e-cigarettes, etc., or flavoring additives for other non-tobacco related products.

Description of the drawings

In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention will be further described below in conjunction with the accompanying drawings, in which:

Figure 1 is a flow chart of an embodiment of a method for preparing tobacco leaf extract using waste tobacco leaves/tobacco dust provided by the present invention.

Detailed ways

Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. The description of the exemplary embodiments is illustrative only and is in no way intended to limit the disclosure, its application or uses. The present disclosure may be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. It should be noted that, unless specifically stated otherwise, the relative arrangements of parts and steps, compositions of materials, numerical expressions, and numerical values set forth in these examples are to be construed as illustrative only and not as limitations.

The terms "first," "second," and similar words used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different parts. Similar words such as "include" or "include" mean that the elements before the word include the elements listed after the word, and do not exclude the possibility of also covering other elements. "Up", "down", etc. are only used to express relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

In this disclosure, when a specific component is described as being between a first component and a second component, there may or may not be an intervening component between the specific component and the first component or the second component. When a specific component is described as being connected to other components, the specific component may be directly connected to the other components without intervening components, or may not be directly connected to the other components but have intervening components.

All terms (including technical terms or scientific terms) used in this disclosure have the same meanings as understood by one of ordinary skill in the art to which this disclosure belongs, unless otherwise specifically defined. It should also be understood that terms defined in, for example, general dictionaries should be construed to have meanings consistent with their meanings in the context of the relevant technology and should not be interpreted in an idealized or highly formalized sense, except as expressly stated herein. Define it this way.

Techniques, methods and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the techniques, methods and devices should be considered a part of the specification.

As shown in Figure 1, the embodiment of the present invention provides a method for preparing tobacco leaf extract using waste tobacco leaves/tobacco powder. In the actual execution process, the method specifically includes the following steps:

Step S1: Near-critical water liquefies the waste tobacco leaves/tobacco powder, add the waste tobacco leaves/tobacco powder sample and distilled water into the reaction kettle according to the preset ratio, seal the reaction kettle, heat the reaction kettle to the target temperature according to the preset heating rate, and keep the temperature preset. After the set time, cool naturally to room temperature, discharge the material, and obtain the solid phase and liquid phase through filtration or centrifugal separation. At the same time, the gas generated during the reaction is collected.

Near-critical water refers to heating water above the boiling point (150°C-350°C) and controlling its pressure to keep the water in a liquid state. At this time, the water is in a liquid state of high temperature and high pressure. In the near-neighbor boundary state, the dielectric constant of water decreases significantly, and water changes from polar compounds to non-polar compounds. Because the polarity of water weakens, many compounds that were originally insoluble in water become soluble in water, so near-critical water is an excellent extraction agent. The present invention uses near-critical water technology, does not use any organic reagents, catalysts, etc., only uses waste tobacco leaves/tobacco dust and water as raw materials, and prepares waste tobacco leaves/tobacco dust extract under the conditions of its own acid catalysis and alkali catalysis. Since organic solvents, acid-base catalysts and other substances are not used in the extraction process, using near-critical water to extract substances is a green processing method. This extraction process is not only environmentally friendly and low-priced, but more importantly, the extraction process can even be completed in a few seconds to ten minutes. In addition, the high temperature and high pressure state of near-critical water can also cause pyrolysis and oxidative decomposition of many different macromolecular substances.

Among them, in the step of liquefying waste tobacco leaves/tobacco powder with near-critical water, the mixing ratio of waste tobacco leaves/tobacco powder samples and distilled water is 1:2-1:20; the waste tobacco leaves/tobacco powder samples and distilled water are preset After the proportion is added to the reaction kettle, the total volume of the materials accounts for 1:3-3:4 of the volume of the reaction kettle; the heating rate of the reaction kettle is 8°C/min-15°C/min, for example, 10°C/min; the target of the reaction kettle The temperature is 160℃-260℃, the vapor pressure corresponding to the target temperature is 0.5MPa-6.0MPa, and the holding time at the target temperature is 5min-20min; after the preset time of holding, turn off the heating switch of the controller to allow natural cooling to room temperature. .

Further, the collection of gas generated during the reaction includes:

The gas generated during the reaction is collected through a gas sampling bag connected to the needle valve on the lid of the reaction kettle, and the gas sampling bag is weighed on an electronic balance before and after collecting the gas, and the mass is recorded as m ₀ (Kg) and m ₁ (Kg), use the difference subtraction method to obtain the gas yield.

m _gas =m ₁ -m ₀ (1)

Among them, M represents the mass (Kg) of waste tobacco leaves/tobacco powder raw materials.

Step S2. Analysis of the components of the waste tobacco leaves/tobacco powder extract. The obtained solid phase residue is extracted with an organic solvent and filtered. The filter residue is washed and dried to a constant weight. After the filtrate is concentrated and extracted, GC-MS (gas chromatography mass spectrometry) is used. Analyze the components of waste tobacco leaves/tobacco powder extracts using an instrument.

Wherein, in the step of analyzing the components of the waste tobacco leaf/tobacco powder extract, the organic solvent used to extract the solid phase residue can be, for example, acetone, and the time for extracting the solid phase residue obtained by the organic solvent is 2h-12h.

Further, after the filter residue is washed and dried to a constant weight, the residue rate and conversion rate are calculated,

Among them, M represents the mass of waste tobacco leaves/tobacco powder raw materials (Kg), and m _residue represents the mass of solid phase residue after drying (Kg).

In one embodiment of the present invention, according to the example in Table 1, a certain amount of waste tobacco leaves/tobacco dust samples and a certain amount of distilled water are added into the reaction kettle, and the reaction kettle is closed. According to the heating rate of 10℃/min, increase the temperature and heat the reaction kettle to 160-260℃. Under corresponding conditions, the reaction endpoint vapor pressure at different experimental temperatures is approximately 0.5MPa-6.0MPa. Under the experimental end-point temperature conditions, maintain a constant temperature for 15 minutes. After constant temperature, turn off the heating switch of the controller, cool to room temperature naturally, and discharge the material. The solid phase and liquid phase are then separated by filtration or centrifugation. The reaction conditions, residue rate, conversion rate, and gas yield are shown in Table 1.

Table 1 Experimental results

Furthermore, after the filtrate was concentrated by a rotary evaporator, it was extracted with ethyl acetate, chloroform, and n-hexane, and GC-MS was used to analyze the components of the waste tobacco leaves/tobacco powder extracts obtained by different processing methods. In order to analyze The components in the liquid phase product were selected from three organic solvents: ethyl acetate, chloroform, and n-hexane. The polarities of these three organic solvents are quite different, and the polarity of near-critical water is also quite different. Therefore, these three organic solvents were used. The organic solvent further extracts the obtained liquid phase product, which is beneficial to analyzing the components in the liquid phase product.

Specifically, the extract obtained by n-hexane extraction includes alcohols and benzene, the extract obtained by ethyl acetate extraction includes esters, phenols and alcohols, and the extract obtained by chloroform extraction includes pyridine. Azine heterocyclic compounds, phenols and aldehydes and ketones.

The following is an introduction using T6 as an example. The liquid phase product obtained from T6 was extracted using the organic solvents ethyl acetate, chloroform, and n-hexane. Different processing methods were analyzed to obtain the aroma components in the waste tobacco leaf/tobacco dust extract. Compared with the 150 substances in Shimadzu's fragrance ingredient library, the results are shown in Table 2. After extraction with n-hexane, ethyl acetate and chloroform, 23, 25 and 24 fragrance ingredients were detected respectively, totaling 39 kinds. Fragrance substances. The main aroma substances detected are alcohols, esters, pyrazines, phenols, aldehydes and ketones. The n-hexane extract contains more alcohols and benzene substances, the ethyl acetate extract contains more esters, phenols and alcohols, and the chloroform extract mainly contains pyrazine heterocyclic compounds and phenols. Aldehydes and ketones. Since waste tobacco leaf/tobacco powder extract contains nicotine, nicotine degradation products, esters, phenols and other substances, and contains many aromatic substances, the extract can be used in tobacco products and other new tobacco products such as heated and non-heated tobacco products. Flavoring additives for combustion cigarettes, e-cigarettes, etc., or additives for other non-tobacco related products, realize the conversion of low economic value waste tobacco leaves/tobacco powder into high value-added tobacco leaf extract liquid.

Table 2T6 Screening results of MRM data of odor components of tobacco leaf samples extracted with different solvents

Note: "-" means not detected; the search database is: Shimadzu Off-flavor odor analysis database, with a total of 150 compounds.

The method for preparing tobacco leaf extract using waste tobacco leaves/tobacco powder provided by the embodiment of the present invention uses near-critical water technology, does not use any organic reagents, catalysts, etc., only uses waste tobacco leaves/tobacco powder and water as raw materials, and has acid in itself. Under the conditions of catalysis and alkali catalysis, waste tobacco leaves/tobacco powder extracts are prepared to realize the conversion of waste tobacco leaves/tobacco powder with low economic value into tobacco leaf extracts with high added value; the method used in the present invention has simple conditions and high reaction efficiency. It is short in time, energy consumption, no secondary pollution in the synthesis process, and is green and environmentally friendly; the waste tobacco leaf/tobacco dust extract prepared by the invention effectively realizes the reuse of waste tobacco leaf/tobacco dust resources, and provides a waste tobacco leaf/tobacco dust extract. Conversion pathway of tobacco powder resources; the waste tobacco leaf/tobacco powder extract prepared by this method contains nicotine, nicotine degradation products, esters, phenols and other substances, contains many aroma substances, and can be used in tobacco products, other In the flavoring of new tobacco products such as heat-not-burn cigarettes, e-cigarettes, etc., or the flavoring of other non-tobacco-related products.

Up to this point, various embodiments of the present disclosure have been described in detail. To avoid obscuring the concepts of the present disclosure, some details that are well known in the art have not been described. Based on the above description, those skilled in the art can completely understand how to implement the technical solution disclosed here.

Although some specific embodiments of the present disclosure have been described in detail through examples, those skilled in the art will understand that the above examples are for illustration only and are not intended to limit the scope of the disclosure. Those skilled in the art should understand that the above embodiments can be modified or some technical features can be equivalently replaced without departing from the scope and spirit of the present disclosure. The scope of the disclosure is defined by the appended claims.

Claims (6)

1. A method for preparing tobacco leaf extract and analyzing components by using waste tobacco leaves/tobacco dust is characterized by comprising the following steps:

adding a waste tobacco leaf/tobacco powder sample and distilled water into a reaction kettle according to a preset proportion, sealing the reaction kettle, heating the reaction kettle to a target temperature according to a preset heating rate, preserving heat for a preset time, naturally cooling to room temperature, discharging, filtering or centrifugally separating to obtain a solid phase and a liquid phase, and collecting gas generated in the reaction process, wherein in the step of liquefying the waste tobacco leaf/tobacco powder by near-critical water, the mixing ratio of the waste tobacco leaf/tobacco powder sample and distilled water is 1:2-1:20, in the step of liquefying the waste tobacco leaf/tobacco powder by near-critical water, the target temperature of the reaction kettle is 160-260 ℃, the heating rate of the reaction kettle is 8 ℃/min-15 ℃/min, the vapor pressure corresponding to the target temperature is 0.5-6.0 MPa, and the preserving heat time at the target temperature is 5-20 min;

analyzing the components of the waste tobacco leaf/tobacco powder extract, extracting the obtained solid phase residue with an organic solvent, filtering, washing the filter residue, drying to constant weight, concentrating and extracting the liquid phase, analyzing the components of the waste tobacco leaf/tobacco powder extract by adopting GC-MS,

wherein in the step of analyzing the components of the waste tobacco leaf/tobacco powder extract, the liquid phase is concentrated by a rotary evaporator, and then extracted by ethyl acetate, chloroform and normal hexane respectively, the components of the waste tobacco leaf/tobacco powder extract obtained by different treatment modes are analyzed by GC-MS,

the extracts obtained by n-hexane extraction comprise alkanes, alcohols and benzene, the extracts obtained by ethyl acetate extraction comprise esters, phenols and alcohols, and the extracts obtained by chloroform extraction comprise pyrazine heterocyclic compounds, phenols and aldehyde ketones.

2. The method for preparing tobacco leaf extract and analyzing components by using waste tobacco leaves/tobacco powder according to claim 1, wherein in the step of liquefying the waste tobacco leaves/tobacco powder by near-critical water, the total volume of materials is 1:3-3:4 of the volume of the reaction kettle after the waste tobacco leaves/tobacco powder sample and distilled water are added into the reaction kettle according to a preset proportion.

3. The method for preparing tobacco leaf extract and component analysis using waste tobacco leaf/tobacco powder as claimed in claim 1, wherein in the step of liquefying waste tobacco leaf/tobacco powder with near-critical water, after a preset time of heat preservation, a controller heating switch is turned off to cool naturally to room temperature.

4. A method for preparing tobacco leaf extract and component analysis using waste tobacco leaf/tobacco powder according to claim 3, wherein in the step of liquefying waste tobacco leaf/tobacco powder with near-critical water, the collecting gas generated during the reaction process comprises:

collecting gas generated in the reaction process through a gas sampling bag connected with a needle valve on the reaction kettle cover, respectively weighing the gas sampling bag on an electronic balance before and after collecting the gas, and respectively marking the mass as m ₀ And m ₁ By means of a difference subtraction, a gas yield is obtained,

m _{air flow} ＝m ₁ -m ₀ (1)

Wherein M represents the mass of the waste tobacco leaf/tobacco powder raw material.

5. The method for preparing a tobacco leaf extract and analyzing components by using waste tobacco leaves/tobacco powder according to claim 1, wherein in the step of analyzing components of the waste tobacco leaves/tobacco powder extract, the time of extracting the solid phase residue obtained by the organic solvent is 2-12 hours.

6. The method for preparing tobacco leaf extract and analyzing components by using waste tobacco leaf/tobacco powder according to claim 1, wherein in the step of analyzing components of the waste tobacco leaf/tobacco powder extract, the residue rate and conversion rate are calculated after the filter residue is washed and dried to constant weight,

wherein M represents the mass of the waste tobacco leaf/tobacco powder raw material, and M _{Residues from the treatment of plant diseases} Indicating the quality of the solid phase residue after drying.