Method for extracting tobacco flavor, flavor additive and aerosol generating substrate

Abstract

The invention provides a method for extracting tobacco flavor from waste tobacco leaves, a flavor additive, an aerosol generating substrate and an aerosol generating product. The method for extracting the tobacco flavor from the waste tobacco leaves comprises the following steps: adding the waste tobacco leaves into dry distillation equipment, introducing water vapor and inert gas into the dry distillation equipment, heating the dry distillation equipment to 300-380 DEG C so as to simultaneously perform distillation and dry distillation on the waste tobacco leaves, collecting distillate in the whole distillation-dry distillation process, and adsorbing the distillate by using macroporous resin XAD-4, finally, ethyl alcohol with the volume fraction being 85%-95% is used for recycling the adsorbate, the tobacco perfume suitable for perfuming novel tobacco products is obtained, and meanwhile the perfume can be directly used as a perfume additive to be added into an aerosol generating substrate or an aerosol generating product. According to the method, efficient utilization of the waste tobacco leaves is achieved, and bad flavor substances are reduced through the method for extracting the tobacco flavor.

Description

Technical Field

[0001] The invention relates to the field of tobacco flavors, and in particular to a method for extracting tobacco flavors from waste tobacco leaves, a flavor additive, an aerosol generating matrix and an aerosol generating product. Background Art

[0002] Tobacco is one of the most widely planted cash crops. With the continuous development of society and the increasing awareness of the public about personal health protection, new tobacco products are developing rapidly as an important substitute for traditional tobacco. For example, heated cigarettes are new tobacco products that use special heat sources to heat below 350°C without causing tobacco combustion. Compared with the combustion temperature range of 700-900°C of traditional cigarettes, the temperature of heated cigarettes is lower, and they cannot release enough aroma-causing substances without being burned, resulting in a weak aroma. External flavoring is needed to enhance the aroma and strength. The tobacco flavors extracted by existing methods cannot meet their requirements.

[0003] Tobacco leaf raw materials contain a small amount of free aromatic components, which can be extracted to obtain tobacco essential oil through steam distillation, solvent extraction, and supercritical CO2 extraction methods. The overall yield is low, usually between 0.2% and 1.0%, and it lacks the characteristic aromas required for tobacco, such as roasted aroma, paste aroma, and baking aroma.

[0004] There are also existing improvements in the extraction of flavor substances from tobacco raw materials, such as the use of high-temperature heating to increase the yield of flavor substances. However, the final material composition is complex and needs to be collected separately at different temperature ranges and extracted by extraction. There is still room for improvement in the extraction efficiency and flavor of flavor substances. Summary of the invention

[0005] The invention provides a method for extracting tobacco flavor from waste tobacco leaves, so as to solve the above technical problems.

[0006] The present invention provides a method for extracting tobacco flavor from waste tobacco leaves, comprising:

[0007] Distillation-drying: adding waste tobacco leaves to the dry distillation equipment, introducing water vapor and inert gas into the dry distillation equipment, and heating the dry distillation equipment to a reaction temperature of 300-380°C to simultaneously distill and dry distill the waste tobacco leaves;

[0008] Collection: Collect the distillate distilled during the entire distillation-drying process;

[0009] Elution and recovery: The distillate is adsorbed and eluted with a macroporous adsorption resin XAD-4 column, and the adsorbate is recovered with ethanol with a volume fraction of 85-95% to obtain an ethanol solution containing flavor components.

[0010] By adopting the above technical scheme, waste tobacco leaves after the extraction of flavor components can be reused. The remaining components in the waste tobacco leaves are reacted by distillation and dry distillation to generate flavor components of specific types and proportions. The above method of extracting tobacco flavors from waste tobacco leaves is specifically suitable for the synthesis and extraction of flavors from waste tobacco leaves. This is because the waste tobacco leaves that have undergone an extraction process retain the precursor substances that produce flavors, and the aromatic substances produced by chemical reactions at high temperatures are exactly what is needed. The tobacco leaves that have not undergone the extraction process produce too complex material components during the dry distillation process. If you want to obtain the desired flavor substances, you need to extract them in sections, and the flavor is not good. The method of the present invention can significantly reduce the bad flavor substances in the components finally obtained. In addition, the components obtained by the above method can be directly added to aerosol generating products as additives.

[0011] Optionally, the flow rate of water vapor introduced into the dry distillation equipment is 400-600 g / h, the flow rate of inert gas introduced is 100-130 ml / min, and further, the flow rate of water vapor introduced is 500 g / h, and the flow rate of inert gas introduced is 120 ml / min.

[0012] Optionally, before distillation and carbonization, the carbonization equipment is preheated to 60-80°C, and then the waste tobacco leaves are added, and the preheating temperature is further 80°C.

[0013] Optionally, after preheating, the heating rate from the preheating temperature to the reaction temperature is 5-6°C / min.

[0014] Optionally, the reaction temperature is maintained for 15 to 25 minutes after reaching the reaction temperature.

[0015] Optionally, after the collection step, the distillate is filtered using filter paper and then subjected to the adsorption and elution step.

[0016] Optionally, the distillate is added to a XAD-4 column at an elution flow rate of 3-6 ml / min and the desorption flow rate with ethanol is 1-2 ml / min.

[0017] Optionally, during the recovery process of the adsorbent by ethanol, one sample segment is collected every minute, and a total of 7 sample segments are collected, and the 3rd to 6th sample segments are combined as the final ethanol solution containing flavor components.

[0018] Optionally, after the adsorption elution, the remaining liquid in the XAD-4 column is removed by pressurizing with compressed air, and then desorption is performed with ethanol.

[0019] Optionally, the waste tobacco leaves are tobacco waste materials remaining after the tobacco raw materials are subjected to steam distillation, supercritical CO2 extraction or organic solvent extraction of tobacco essential oil.

[0020] The invention also provides a flavor additive, which is an ethanol solution directly obtained by extracting tobacco flavor from waste tobacco leaves.

[0021] The flavor additive of the above technical solution has low undesirable flavor substances, has flavor components of specific types and proportions, and can be directly added to an aerosol generating matrix.

[0022] The present invention also provides an aerosol-generating substrate comprising a flavoring additive.

[0023] The aerosol-generating matrix of the above technical solution has a strong fragrance, a good taste, and low odor such as burnt smell.

[0024] The present invention also provides an aerosol generating product, which comprises a fragrance additive, wherein the fragrance additive can be arranged at any part of the aerosol generating product.

[0025] The aerosol-generating product of the above technical solution has excellent roasted aroma and burnt sweet aroma. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the equipment used in the tobacco flavor extraction process of the present invention.

[0027] Figure 2 It is a flow chart of the tobacco flavor extraction process in a specific embodiment of the present invention. DETAILED DESCRIPTION

[0028] The following is an explanation of the embodiments of the present invention by specific specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Although the description of the present invention will be introduced in conjunction with the preferred embodiment, this does not mean that the features of this invention are limited to this embodiment. On the contrary, the purpose of introducing the invention in conjunction with the embodiment is to cover other options or modifications that may be extended based on the claims of the present invention. In order to provide a deep understanding of the present invention, the following description will include many specific details. The present invention can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present invention, some specific details will be omitted in the description. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0029] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0030] The common methods for extracting flavor substances from tobacco raw materials are steam distillation, supercritical CO2 extraction or organic solvent extraction of tobacco raw materials to extract tobacco essential oil. Specifically, steam distillation is to pass water vapor into a mixture containing organic matter that is insoluble or slightly soluble in water but has a certain volatility, and heat it to boil. The flavor organic matter to be purified can be distilled out together with the water vapor at a temperature below 100°C, thereby achieving the purpose of separating and purifying tobacco essential oil; supercritical CO2 extraction is to contact a supercritical fluid with a tobacco leaf material to be separated under a supercritical state, so that it selectively extracts tobacco essential oil components with different polarity, boiling point and molecular weight at one time, and then the supercritical fluid is turned into an ordinary gas by means of a decompression and heating method, and the extracted tobacco essential oil material is completely or substantially precipitated, thereby separating the tobacco essential oil component from the tobacco leaf; organic solvent extraction is based on the principle of like dissolves, and selects an organic solvent such as petroleum ether, ethyl acetate, ethanol, etc. that is similar in structure to the tobacco essential oil component, and utilizes the difference in solubility and partition coefficient of tobacco essential oil in two mutually immiscible (or slightly soluble) solvents to transfer the tobacco essential oil material from one solvent to the above-mentioned organic solvent, thereby extracting the tobacco essential oil component. For the above extraction methods, the tobacco leaves usually selected are the discarded tobacco leaf fragments, tobacco stems, etc. in the production process. Since the discarded tobacco leaf fragments and tobacco stems are already recycled, they will be discarded as tobacco waste after extraction. However, the inventors found that the extraction efficiency of the existing conventional extraction process is not high, and there are still aroma substances in the tobacco waste. Although the aroma substances are difficult to extract by the above method, the inventors consider using an improved process to reuse the discarded waste tobacco leaves.

[0031] To this end, the present application adopts the distillation-drying method to react tobacco flavors in waste tobacco leaves, and evaporates them to form distillates, which not only satisfies the pyrolysis and further chemical reactions of flavor precursors at higher temperatures to produce a large amount of flavor substances, but also makes it easier for water vapor to bring out the generated flavor substances. In addition, the inventors have also found that for waste tobacco leaves that have been extracted with flavors once, although a new flavor substance composition can be obtained by using the distillation + dry distillation method, undesirable flavor substances that are rarely present in the extraction of tobacco raw materials will be produced. If the distillate obtained by distillation + dry distillation in the usual way is used to extract flavor substances, and then added to cigarettes for use, it will destroy the taste of the cigarettes.

[0032] To this end, the inventors have studied and adopted the following technical solutions to solve the above problems.

[0033] The present application proposes a method for extracting tobacco flavor from waste tobacco leaves, comprising:

[0034] Distillation-drying: adding waste tobacco leaves to the dry distillation equipment, introducing water vapor and inert gas into the dry distillation equipment, and heating the dry distillation equipment to a reaction temperature of 300-380°C to simultaneously distill and dry distill the waste tobacco leaves;

[0035] Collection: Collect the distillate distilled during the entire distillation-drying process;

[0036] Elution and recovery: The distillate is adsorbed and eluted with a macroporous adsorption resin XAD-4 column, and the adsorbate is recovered with ethanol with a volume fraction of 85-95% to obtain an ethanol solution containing flavor components.

[0037] Compared with extracting aromatic substances by subjecting the distillate to organic solvent extraction, the present application uses macroporous adsorption resin XAD-4 to adsorb and elute the distillate, and selects ethanol with a volume fraction of 85-95% to recover the adsorbate, which is beneficial to the removal of undesirable flavor substances in the distillate. At the same time, it can also collect small molecular substances with aroma, thereby obtaining a more pure combination of aromatic substances. Specifically, the present invention uses ethanol to enrich the flavor components because ethanol can extract the flavor substances adsorbed on the macroporous resin XAD-4. Ethanol with a volume fraction of 85-95% has a certain solubility for most flavor compounds and a good enrichment effect. In addition, ethanol can be directly used as a flavor solvent and directly applied to new tobacco products. The present invention has found through experiments that the extraction effect is better when the volume fraction of ethanol is within the range of 85-95%. If the ethanol concentration is too low, on the one hand, the yield of the extracted flavor is low, and the enrichment effect is not good, resulting in the roasted flavor and burnt sweet flavor of the ethanol containing the flavor components being added to the cigarette after being smoked is not strong enough, and also containing unpleasant flavors. On the other hand, the ethanol solution containing the flavor components contains a certain amount of water. Excessive water content will affect the addition amount of other non-polar compounds in subsequent flavoring applications. At the same time, too much water content will affect the moisture content of the cigarette. When it is subsequently added to the cigarette, the drying time and the subsequent water removal process are additionally increased, resulting in a decrease in the efficiency of the entire cigarette preparation process, and also resulting in a loss of flavor components, which reduces the strength and flavor of the cigarette after being added, resulting in a poor smoking taste after being added to the cigarette. If the ethanol concentration is too high, the desorption capacity is too strong, resulting in poor separation effect of the resin, too high compound enrichment, and inability to remove impurities. The ethanol concentration in the range of 85-95% by volume can efficiently extract flavor substances. The adsorption elution of the macroporous resin XAD-4 combined with the recovery of 85-95% by volume ethanol makes the ethanol solution containing flavor components added to the cigarette have a better smoking feel.

[0038] Experiments have shown that by using a reaction temperature of 300-380°C for dry distillation, using steam distillation, combining XAD-4 column adsorption elution and recovery of ethanol at a specific volume fraction, the ethanol solution itself can be directly added to the aerosol generation matrix as a flavor additive. After elution and recovery, no other treatment is required and it can be used directly, which is convenient and efficient. Ethanol not only plays a role in recovery, but also can volatilize quickly when the ethanol solution containing flavor components is directly added to the cigarette, and the flavor substances dissolved therein exist in the cigarette, which will not affect the use of the cigarette.

[0039] The macroporous adsorption resin XAD-4 is selected. On the one hand, the macroporous adsorption resin has a macroporous network structure and a large specific surface area, and has a high adsorption capacity. On the other hand, the special pore structure of XAD-4 can adsorb relatively low molecular weight organic substances, which has certain advantages in the adsorption of flavor substances. The inventors also tried other methods of extracting flavor substances and found that the macroporous adsorption resin XAD-4 is particularly suitable for the distillate of waste tobacco leaves after distillation and dry distillation.

[0040] The waste tobacco leaves selected by the present invention can be flue-cured tobacco, sun-cured tobacco, air-dried tobacco or other tobacco raw materials left after the above-mentioned conventional extraction method, or a mixture of tobacco wastes extracted from multiple raw materials. It has been found through research that whether it is a single variety of waste tobacco leaves, or a mixture of waste tobacco leaves composed of a mixture of multiple tobacco raw materials after extraction to become waste tobacco leaves, the combination of the steam distillation and dry distillation method of the present invention can make the precursor of the waste tobacco leaves crack its unique hemicellulose, cellulose, lignin, protein, pectin and other substances at high temperature, and then use XAD-4 macroporous resin to absorb the flavor components, thereby obtaining a different combination of flavor components formed after distillation and dry distillation of tobacco raw materials, these components are more related to the baking flavor, the components are purer, and can be directly used as a basic formula.

[0041] The macroporous adsorption resin XAD-4 combined with 85-95% ethanol extract has a good enrichment effect on the aroma substances, and the bad flavor substances are effectively reduced. When added to the heated cigarette, the burnt smell is significantly improved.

[0042] By utilizing the adsorption effect of XAD-4 and the desorption capacity of 85%-95% ethanol, water-soluble impurities can be removed on the one hand, and small molecular impurities can be removed according to the different polarities of the compounds during the desorption process on the other hand. In particular, the liquid that has not been adsorbed and recovered by the XAD-4 resin has a high content of benzopyrrole. In the ethanol solution obtained by the extraction method of the present application, the final content of benzopyrrole can be below 1.1%, and the burnt odor is removed.

[0043] If the distillate is extracted by solvent, an extractant suitable for extracting flavor substances will inevitably be used. These extractants are not suitable for adding to cigarettes, so an additional step of removing the solvent is required, such as rotary evaporation. This will increase the steps and reduce the production efficiency of large-scale production. On the other hand, the rotary evaporation method will also cause the loss of some flavor substances. In addition, it has been found that the distillate of waste tobacco leaves after dry distillation and distillation cannot effectively solve the problem of bad flavor substances by using the usual extraction method, and the extraction rate of flavor substances is also lower than the elution and recovery method of this application.

[0044] The waste tobacco leaves mentioned in this application do not refer to tobacco leaf fragments, tobacco ends, tobacco stems and other tobacco waste discarded in the tobacco production process. The waste tobacco leaves mentioned in this application refer to the tobacco leaf waste remaining after the tobacco raw materials are subjected to steam distillation, supercritical CO2 extraction or organic solvent extraction of tobacco essential oil components. Specifically, waste tobacco leaves obtained by steam distillation refer to tobacco leaf fragments placed in a steam distillation kettle, through which saturated clean steam is introduced, the condensed liquid carrying aroma substances is collected by a condensation system, and the aqueous phase and the organic phase are separated by a separatory funnel. The organic phase is the tobacco essential oil component of steam distillation, and the discarded tobacco leaves in the steam distillation kettle are taken out and dried to obtain the waste tobacco leaves referred to in the present invention; and waste tobacco leaves obtained by supercritical CO2 extraction refer to tobacco leaf fragments being extracted by a supercritical extraction kettle under the action of high pressure, low temperature and a carrying agent to obtain a supercritical CO2 tobacco extract, and the remaining tobacco leaves in the extraction kettle are the waste tobacco leaves obtained by supercritical CO2 extraction; waste tobacco leaves obtained by organic solvent extraction refer to tobacco leaf fragments being immersed in an organic solvent, stirred and extracted at a certain heating temperature, filtered, and the waste residue is removed and concentrated to obtain a tobacco paste extract, and the remaining waste residue is dried to remove the solvent to obtain the waste tobacco leaves obtained by organic solvent extraction.

[0045] These existing extraction methods are usually not subjected to dry distillation, and are mainly based on physical extraction. After normal extraction by the existing method, the waste tobacco leaves have no use value, but the extraction method of the present application can be used to recycle and reuse the waste tobacco leaves. This is because the waste tobacco leaves after extraction contain a large amount of hemicellulose, cellulose, lignin, protein, pectin, etc., and the waste tobacco leaves after extraction basically retain these substances. These substances can be used as precursors of spices. Under conditions such as high temperature and suitable medium, pyrolysis and corresponding chemical reactions, such as Maillard reaction, will occur, producing aldehydes, ketones, aromatic rings, furans, heterocyclics and other aromatic substances. The number of aromatic components produced by these precursors is much higher than the free aromatic components in the original tobacco, and can provide the roasted aroma and sweet aroma required for the aroma of cigarettes, and the produced aroma is purer, which can enhance the smoking quality.

[0046] The material composition of waste tobacco leaves after distillation and dry distillation is different from the material composition of tobacco raw materials after distillation and dry distillation. The present application collects the distillate distilled during the entire distillation-dry distillation process, that is, water vapor and inert gas are introduced for distillation and dry distillation from the beginning of the temperature rise until the distillate in the entire temperature range reaching the reaction temperature is collected together and directly used as a flavor additive after elution and recovery. The waste tobacco leaves used in the present application are combined with the above-mentioned extraction method, which is suitable for the collection and merging of substances in the entire temperature range. The combined components are added to the cigarettes to bring a better taste to the cigarettes, and the combined components have a higher yield.

[0047] The dry distillation equipment is a relatively closed environment. The extraction method of the present application introduces water vapor and inert gas into the dry distillation equipment. The inert gas prevents the waste tobacco leaves from undergoing oxidation reactions at high temperatures. For example, the inert gas can be nitrogen, argon, etc. The present application can use nitrogen + superheated water vapor to pass through the equipment. The aroma substances produced by the waste tobacco leaves are brought out by the water vapor. The water vapor flowing out of the dry distillation equipment is collected through condensation by external equipment to obtain a distillate. The heating temperature of the waste tobacco leaves during the distillation and dry distillation process is 300-380°C. This temperature range is suitable for the reaction of the waste tobacco leaves to generate flavor components with better taste. The temperature has a great influence on the product yield and aroma quality. If the temperature is too low, the pyrolysis of the flavor precursor is incomplete, the yield is low, and the characteristic aroma of roasted and sweet cigarettes is also lacking. If the temperature is too high, the product will have a heavy bitter taste, affecting the aroma quality. Furthermore, the reaction temperature can be 320-360°C, and further 350°C. The reaction temperature is set at 350°C, so that the extracted flavor substances have both excellent roasted aroma and burnt sweet aroma.

[0048] The water vapor introduced into the dry distillation device is superheated water vapor, which can be heated to 150-210° C., specifically, to 200° C. before being introduced into the dry distillation device, and then introduced into the dry distillation device together with the inert gas.

[0049] Further, the flow rate of the water vapor introduced into the dry distillation equipment is 400-600g / h, and the flow rate of the inert gas introduced is 100-130ml / min. The water vapor and the inert gas can be heated before being introduced into the dry distillation equipment. During the whole process, the water vapor and the inert gas are completely mixed. The inert gas prevents the substances in the dry distillation equipment from undergoing oxidation reactions, and the water vapor is used to bring out the aroma substances produced in the dry distillation equipment in time. It has been verified experimentally that the flow rates of the water vapor and the inert gas match each other, which is particularly suitable for the distillation-dry distillation process of waste tobacco leaves, is more conducive to the effective extraction of aroma components, avoids the waste tobacco leaves from producing burnt smell, and can also obtain a distillate with a suitable concentration, so as to facilitate subsequent elution recovery and the concentration of the aroma components in the ethanol solution finally obtained is controlled within a suitable range. Preferably, the flow rate of the water vapor introduced is 500g / h, and the flow rate of the inert gas introduced is 120ml / min.

[0050] Before distillation and dry distillation, the dry distillation equipment is preheated to 60-80°C, and then waste tobacco leaves are added. Preheating the dry distillation equipment helps to remove the air in the equipment and also helps the subsequent rapid heating process to avoid excessive temperature differences that may cause the generation of undesirable substances during the reaction.

[0051] In the above embodiments, after preheating, the heating rate from the preheating temperature to the reaction temperature is 5-6°C / min. For example, the preheating temperature is 80°C, the reaction temperature is 350°C, and the heating rate from 80°C to 350°C is 5-6°C / min. Different from the general heating rate, the distillation-drying process of waste tobacco leaves in this application needs to reach the reaction temperature within a set time range at a higher heating rate to obtain a suitable reaction time, which will eventually affect the types and contents of each component in the obtained distillate. In addition, the heating rate of 5-6°C / min can also match the flow rate of 400-600g / h of water vapor and the flow rate of 100-130ml / min of inert gas mentioned in the above embodiments. In addition, the heating rate of the present application is relatively high, which can also prevent the inert gas with a large flow rate from taking away some of the aroma substances, which is beneficial to improve the yield of the aroma substances.

[0052] Furthermore, in the above embodiments, after reaching the reaction temperature, the temperature is kept for 15 to 25 minutes, more specifically, for 20 minutes, and then the reaction is terminated, and all distillates from the preheating to the end of the temperature keeping are collected.

[0053] Furthermore, in the above embodiment, after the collection step, the distillate is first filtered with filter paper, and then the elution recovery step is performed. The filter paper can be a medium-speed filter paper. The distillate has more components, and filtering can effectively remove impurities that are insoluble in water and organic matter. Before extracting the required flavor components, filtering is performed to remove impurities, which facilitates the subsequent macroporous resin to more specifically adsorb hydrophobic molecules and relatively low molecular weight organic substances, which is beneficial to the enrichment of flavor components.

[0054] Furthermore, in the above embodiment, the distillate is adsorbed and loaded with a macroporous resin XAD-4, and the loading rate is 3-6 ml / min. Within this range, the generated aroma substances can be fully adsorbed on the macroporous resin XAD-4, so that the aroma substances will not penetrate the column and cause loading loss, and the loading time is short, saving process costs. Furthermore, the loading rate is 4 ml / min;

[0055] Further, the flow rate of ethanol desorption is 1-2ml / min, and the flow rate can ensure that the spices are fully extracted within the range, and the desorption time will not be excessively extended, and the loss of volatile aroma substances can be reduced at the same time. The flow rate of ethanol desorption is 1-2ml / min, preferably, the flow rate of ethanol desorption is 1ml / min, at this flow rate, the fragrance components can be extracted into ethanol to the greatest extent, and secondly, the distillate is adsorbed and loaded by macroporous resin XAD-4, and most of the water-soluble substances are not adsorbed, and have been removed, and the overall composition of the distillate is reduced, and the fragrance components have been enriched by macroporous resin XAD-4 to a certain extent. On this basis, it is necessary to appropriately reduce the ethanol rate to enrich the fragrance components and remove the adsorbed impurities with ethanol desorption. In addition, the desorption rate is set to 1-2ml / min to facilitate subsequent recovery of sample segments, and the sample segments are more at too high a rate, and the concentration of the fragrance components in the sample segments is low, and the enrichment effect is poor; if the enrichment degree is high when the rate is too low, the separation effect of fragrance substances and impurities in the sample will be weakened.

[0056] Furthermore, in the process of recovering the adsorbent by ethanol, the sample segments of the detected results can be selected according to the actual situation, and different recovery segments can be selected to obtain aroma substances with higher purity. Specifically, for the methods of the above-mentioned embodiments, it is usually possible to choose to collect 7 sample segments, and combine the 3rd to 6th sample segments as the final ethanol solution containing aroma components, which can ensure the purity of the aroma components and reduce the content of undesirable substances.

[0057] Furthermore, in each of the above examples, after the macroporous resin performs the adsorption and elution steps on the distillate, the liquid in the XAD-4 column is removed by pressurizing with compressed air, and then the ethanol is used for desorption. The liquid in the XAD-4 column is removed by pressurizing with compressed air, so that the ethanol can desorb the flavor substances more specifically, which is beneficial to the enrichment of the flavor components.

[0058] In the present invention, the composition of the flavor components finally obtained by distilling and dry distilling, collecting, eluting and recovering the waste tobacco leaves after extraction is different from the flavor components obtained by distilling and dry distilling and extracting the tobacco leaves that have not undergone the extraction process. Figure 1As shown, the experimental equipment used in the distillation-drying and collecting process of the present invention includes a water vapor generating device 1, a compressed nitrogen tank 2, a superheated steam device 3 and a dry distillation device 4, a water cooling system 5 and a product collecting device 6. The water vapor generating device 1 is connected to the superheated steam device 3, the compressed nitrogen tank 2 is connected to the superheated steam device 3, the superheated steam device 3 is connected to the dry distillation device 4, the dry distillation device 4 is connected to the water cooling system 5, and the water cooling system 5 is connected to the product collecting device 6 (the water vapor generating device 1, the superheated steam device 3 and the dry distillation device 4 are all connected to an electrical control cabinet, which can control the temperature and steam volume of these three devices). During the experiment, the main switch of the above devices is turned on through the electrical control cabinet. The following is combined with Figure 1 and Figure 2 The extraction method of the specific implementation mode of the present application is introduced. The dry distillation equipment is preheated, and then the waste tobacco leaves are added into the dry distillation equipment; the water vapor generated by the water vapor generating device and the nitrogen in the compressed nitrogen tank are passed into the superheated steam device to heat the mixed gas; the heated mixed gas is then passed into the dry distillation equipment, and the recovery system is turned on. The recovery system includes a water cooling system and a product collection device; the dry distillation equipment is then heated to 350°C, the distillate is collected, the distillate is filtered to remove impurities, and then the water-soluble impurities are removed by elution with a macroporous resin XAD-4, and then the distillate is desorbed and segmented enriched with a volume fraction of 95% ethanol solution, and the fractions are combined to obtain an ethanol solution containing flavor components. Specifically, after the preheating temperature of the dry distillation equipment 4 reaches 60-80°C, waste tobacco leaves are added to the dry distillation equipment 4, and then the valve of the dry distillation equipment 4 is closed, and the inert gas in the compressed nitrogen tank 2 is passed into the superheated steam device 3. Since the water vapor generating device 1 and the superheated steam device 3 are connected, the compressed nitrogen tank 2 and the superheated steam device 3 are connected, and the water vapor generated by the water vapor generating device 1 will pass into the superheated steam device 3, and the water vapor and nitrogen will be mixed and heated in the superheated steam device 3. After being heated to 200°C, the valve of the dry distillation equipment 4 is opened. At this time, the mixed water vapor and nitrogen will pass into the dry distillation equipment 4, and then the dry distillation equipment 4 is heated from the preheating temperature to the reaction temperature of 300-380°C and then kept warm for 15-25 minutes. The precursor substances of the waste tobacco leaves will undergo pyrolysis and chemical reactions under this condition, and the generated aroma substances will be taken away by the mixed water vapor and inert gas, and then condensed and cooled through the water cooling system 5, and then all the distillates in the distillation-dry distillation process are collected at one time at the collecting device 6. Then, the steps of filtering, adsorption and desorption of macroporous resin XAD-4 are performed. The flavor component composition of the present invention can be directly added to tobacco raw materials or reconstituted tobacco leaves as an additive to form cigarettes and cigarette sticks, and is particularly suitable for use in heat-not-burn smoke-generating bodies. The flavor material extracted by the present invention is not burned, and the flavor component can be well released only in the heated state.

[0059] The tobacco flavor components extracted in the present application can also be added to the aerosol generating matrix as a flavor additive. The "aerosol generating matrix" mentioned in the present invention refers to a matrix that can release volatile compounds when heated, and the volatile compounds can form an aerosol. The aerosol generating matrix can include tobacco materials or non-tobacco materials, or it can contain both tobacco materials and non-tobacco materials. For example, non-tobacco materials can be flavors that can be volatilized by heating or not. The aerosol generating matrix also includes an atomizer, such as glycerol or propylene glycol. The aerosol generating matrix can also include additional ingredients, such as nicotine or flavor extracts. For a solid aerosol generating matrix, a structure of a cigarette cartridge or a cigarette stick can be formed and contained in a smoking device, and further made into a heated cigarette, which will also include a tobacco matrix part and a filter part. The "aerosol generating product" includes an aerosol generating matrix and a filter part, and the whole is used in conjunction with the smoking device for heating or other heating-without-combustion methods to generate an aerosol for inhalation.

[0060] The effects of the present invention are further illustrated below by taking Examples 1-6 and Comparative Examples 1-7 as examples.

[0061] Example 1

[0062] Waste flue-cured tobacco leaves extracted with supercritical CO2 were selected, wherein the supercritical CO2 extraction was to crush the flue-cured tobacco leaves into sesame-sized pieces, place them in a supercritical carbon dioxide extraction kettle, introduce supercritical carbon dioxide, the pressure was 25 MPa, the temperature in the kettle was set to 45°C, the carbon dioxide flow rate was 150 g / min, the entrainer was 95% ethanol, the flow rate was 2.0 ml / min, static extraction was performed for 60 minutes, dynamic extraction was performed for 120 minutes, and the extract under a pressure of 6 MPa was collected. After the extraction is completed, the waste tobacco leaves are removed after volatilization at normal pressure, which is the waste flue-cured tobacco leaves extracted with supercritical CO2 in this embodiment. After that, the dry distillation equipment 4 is preheated to 80°C, 400g of the waste flue-cured tobacco leaves extracted with supercritical CO2 are added to the dry distillation equipment 4, and then the valve of the dry distillation equipment 4 is closed, and nitrogen is passed into the superheated steam device 3. At this time, the water vapor generated by the water vapor generating device 1 will also pass into the superheated steam device 3, and the water vapor and nitrogen will be mixed and heated in the superheated steam device 3. After being heated to 200°C, the valve of the dry distillation equipment 4 is opened, and the mixed superheated water vapor and nitrogen will pass into the dry distillation equipment 4. The flow rates of the superheated water vapor and nitrogen are 500g / h and 120ml / min respectively, and then the dry distillation equipment 4 is heated to 200°C. Preparation 4 is heated at a rate of 5°C / min until it is heated to 350°C, and kept warm for 20 minutes, and then the distillate is condensed and cooled through a water cooling system 5, and finally all the distillates from 80°C to 350°C are collected at a product collection device 6 at one time; thereafter, the distillate is filtered with medium-speed filter paper, and then the distillate is adsorbed and eluted with a macroporous resin XAD-4, and the elution flow rate is 4ml / min. After the elution is completed, the remaining liquid in the column is removed by pressurizing with compressed air, and then the adsorbate is desorbed with ethanol with a volume fraction of 95%, and the desorption flow rate is 1ml / min. One sample segment is recovered per minute, and a total of seven sample segments are collected, and the 3rd to 6th sample segments are selected and combined to obtain an ethanol solution containing flavor components as the final tobacco flavor.

[0063] Example 2

[0064] The same experimental method as in Example 1 is adopted, with the only difference that the waste tobacco leaves selected are flue-cured tobacco waste leaves after steam distillation, wherein the steam distillation is to crush the flue-cured tobacco leaves into sesame-sized pieces and place them in a steam distillation device, and introduce saturated steam to extract the essential oil for 3 hours. After the extraction is completed, the pure dew is placed in a 4°C refrigerator to precipitate the aroma substances, and then the tobacco essential oil and the aqueous solution are separated by a separatory funnel. The remaining waste residue in the steam distillation device is taken out and dried to obtain the flue-cured tobacco waste leaves after steam distillation.

[0065] Example 3

[0066] The same experimental method as in Example 1 was used, except that the waste tobacco leaves selected were flue-cured tobacco waste tobacco leaves extracted with petroleum ether, wherein the petroleum ether extraction was performed by crushing the flue-cured tobacco leaves into sesame-sized pieces and placing them in a glass extraction kettle, adding petroleum ether solvent at a mass volume fraction of 5 times, turning on the stirring device, the speed was 90 rpm, the condensation reflux temperature was controlled at 1°C, the heating temperature was 50°C, the extraction time was 2 hours, and the number of extractions was 2 times. The extract was recovered and concentrated by rotary evaporation to obtain the petroleum ether extract, and the waste residue in the kettle was placed in a fume hood for solvent volatilization to obtain the flue-cured tobacco waste tobacco leaves extracted with petroleum ether.

[0067] Example 4

[0068] The same experimental method as in the above-mentioned Example 1 was used, except that the flow rates of superheated water vapor and nitrogen introduced into the dry distillation device 4 were 300 g / h and 80 ml / min, respectively.

[0069] Example 5

[0070] The same experimental method as in Example 1 was used, with the only difference being that the waste tobacco leaves were a mixture of 400 g of flue-cured tobacco leaves treated with supercritical CO2 and flue-cured tobacco leaves distilled with steam, and the flow rates of superheated steam and nitrogen introduced into the dry distillation device 4 were 700 g / h and 140 ml / min, respectively.

[0071] Example 6

[0072] The same experimental method as in Example 1 was used, except that the heating rate from the preheating temperature to the reaction temperature was 2° C. / min.

[0073] Comparative Example 1

[0074] After the dry distillation equipment 4 is heated to 80°C, 400g of waste flue-cured tobacco leaves extracted with supercritical CO2 are added to the dry distillation equipment, and then the valve of the dry distillation equipment 4 is closed, and then nitrogen is passed into the superheated steam device 3. At this time, the water vapor generated by the water vapor generating device 1 will also pass into the superheated steam device 3. The water vapor and nitrogen are mixed and heated in the superheated steam device 3. After being heated to 200°C, the valve of the dry distillation equipment 4 is opened. At this time, the mixed superheated water vapor and nitrogen will pass into the dry distillation equipment 4. The flow rates of the superheated water vapor and nitrogen are 500g / h and 120ml / min respectively. Then, the dry distillation equipment is heated at a rate of 5°C / min. When the temperature reaches 2 The column is heated to 250°C and then kept warm for 20 minutes. The distillate is then condensed and cooled by a water cooling system 5. The distillate at 200°C to 250°C is collected. The distillate is then filtered with medium-speed filter paper. The distillate is then adsorbed and eluted with a macroporous resin XAD-4 at a flow rate of 4 ml / min. After the elution is completed, the remaining liquid in the column is removed by pressurizing with compressed air. The adsorbate is then desorbed with 95% ethanol by volume at a flow rate of 1 ml / min. One sample segment is recovered per minute. A total of seven sample segments are collected. The 3rd to 6th sample segments are selected and combined to obtain an ethanol solution containing flavor components as the final tobacco flavor.

[0075] Comparative Example 2

[0076] The same experimental method as that of the comparative example 1 was used, except that the waste tobacco leaves used were flue-cured tobacco waste leaves extracted with petroleum ether.

[0077] Comparative Example 3

[0078] After the temperature of the dry distillation device 4 reaches 60°C, 400g of flue-cured tobacco leaf raw material is added to the dry distillation device 4, and then the valve of the dry distillation device 4 is closed, and then nitrogen is passed into the superheated steam device 3. At this time, the water vapor generated by the water vapor generating device 1 will also pass into the superheated steam device 3. The water vapor and nitrogen are mixed and heated in the superheated steam device 3. After being heated to 480°C, the valve of the dry distillation device 4 is opened. At this time, the mixed superheated water vapor and nitrogen will pass into the dry distillation device 4. The flow rates of the superheated water vapor and nitrogen are 300 and 480°C, respectively. g / h, 80ml / min, and then heat the dry distillation device 4 at a rate of 2℃ / min, start collecting when the temperature reaches 200℃, and continue heating until it reaches 250℃. The distillate is condensed and cooled through a water cooling system 5, and the distillate at 200℃ to 250℃ is collected; the distillate is extracted three times with a mixed solvent of ethyl acetate and n-hexane in a volume ratio of 1:1, anhydrous sodium sulfate is added to the extracted mixed solution, and the mixture is stirred for 2h for dehydration, and the solvent is recovered by a rotary evaporator from the dehydrated extracted mixed solution to finally obtain tobacco flavor.

[0079] Comparative Example 4

[0080] The same experimental method as in Example 1 is used, except that the distillate is extracted to obtain the flavor extract, specifically: the distillate is extracted three times with a mixed solvent of ethyl acetate and n-hexane in a volume ratio of 1:1, anhydrous sodium sulfate is added to the extraction mixture, and the mixture is stirred for 2 hours for dehydration, and the solvent is recovered from the dehydrated extraction mixture by a rotary evaporator to finally obtain tobacco flavor.

[0081] Comparative Example 5

[0082] The same experimental method as in the above-mentioned Example 1 was used, except that the volume fraction of the ethanol solution was 75%.

[0083] Comparative Example 6

[0084] The same experimental method as in the above-mentioned Example 1 was used, except that the volume fraction of the ethanol solution was 98%.

[0085] Comparative Example 7

[0086] The same experimental method as in the above-mentioned Example 1 was used, except that the raw material of flue-cured tobacco that had not undergone the extraction process was not waste tobacco leaves.

[0087] Take the tobacco flavor obtained in Examples 1-6 and Comparative Examples 1-6, and calculate the yield. The yield of tobacco flavor (%) = the mass of tobacco flavor / the mass of tobacco base material × 100%. Tobacco flavor refers to the mass of flavor obtained after extraction. The extraction method is, for example, the method of the above-mentioned embodiment or comparative example. The mass of tobacco flavor can be measured by an electronic balance. Tobacco base material refers to the material selected before extraction, such as the raw material added to the dry distillation device 4 in the above-mentioned embodiment and comparative example. The yield results of tobacco flavor in the above-mentioned embodiment and comparative example are recorded in Table 1.

[0088] The tobacco flavors obtained in Examples 1-6 and Comparative Examples 1-6 were used to detect the content of benzopyrrole using a gas chromatography-mass spectrometer, and the results were recorded in Table 1.

[0089] The tobacco flavors extracted from Examples 1-6 and Comparative Examples 1-7 were added to heated cigarettes for smoking, and sensory evaluation was performed to score the five indicators of roasted aroma, light aroma, sweet aroma, woody aroma, and paste aroma. The heated cigarette smoking evaluation was divided into five indicators, namely, aroma, smoke, strength, irritation, and aftertaste. Each indicator was scored according to the scoring principle of 1-9 points for strength, high and low, and size, and the smoking results were recorded in Table 2. No flavor was added, and the heated cigarettes were directly smoked as a blank sample group.

[0090] Take the tobacco flavors obtained in Comparative Example 1 or Comparative Example 2, Comparative Example 3 and Example 1, and quantitatively analyze the products by gas chromatography-mass spectrometry, and record the mass percentage of the main aroma components to the total aroma components in Table 3.

[0091] Table 1 Yield of tobacco flavor and mass fraction of benzopyrrole in different examples

[0092]

[0093]

[0094] Table 2 Heated cigarette smoking results

[0095] Tobacco leaf source fragrance Smoke Momentum Irritant Aftertaste Total score Blank 6.0 6.0 6.0 6.0 6.0 30.0 Example 1 7.0 7.8 6.9 6.9 7.0 35.6 Example 2 7.5 7.4 7.4 7.1 7.2 36.6 Example 3 6.9 7.1 7.3 7.0 7.0 35.3 Example 4 6.6 7.1 6.9 6.8 7.0 34.4 Example 5 6.4 7.0 7.1 6.8 6.3 33.6 Example 6 6.7 6.9 7.2 6.5 6.4 33.7 Comparative Example 1 6.3 7.0 6.7 7.0 6.2 33.2 Comparative Example 2 6.1 6.9 7.0 6.8 6.2 33.0 Comparative Example 3 6.6 6.8 6.6 6.9 6.2 33.1 Comparative Example 4 6.5 6.8 7.2 6.2 6.1 32.8 Comparative Example 5 6.6 6.9 6.7 6.8 6.3 33.3 Comparative Example 6 6.8 6.9 6.9 6.6 6.3 33.5 Comparative Example 7 6.6 6.9 6.6 6.6 6.8 33.5

[0096] Table 3 The mass percentage of main aroma components in the total aroma components

[0097]

[0098]

[0099] According to the results of Tables 1-3 above, compared with the comparative example, the content of benzopyrrole in Examples 1-6 is lower, all below 1.1%, and the other undesirable flavor substances are also effectively removed, corresponding to a better irritation and aftertaste in the mouth. Examples 1-6 can also achieve effective extraction of flavor substances with a high yield.

[0100] Embodiments 1-3 not only have a lower content of benzopyrrole, but also effectively reduce other undesirable flavor substances. Since the adsorption and desorption capacity of XAD-4 macroporous resin for benzopyrrole is somewhat different from that of other main flavor substances, the distillate treated with the macroporous resin contains less benzopyrrole. In addition, the heating rate during the dry distillation and distillation process of the present invention is 5-6°C / min, and the faster heating rate makes the content of benzopyrrole further below 0.95%. Under the premise that the content of benzopyrrole is below 0.95%, the content of benzopyrrole in Embodiments 1-3 is controlled within an appropriate range, and a small amount of benzopyrrole present in the final tobacco flavor can also promote the improvement of the flavor and taste of the tobacco flavor on the cigarette, and the benzopyrrole content in Embodiments 1-3 is within an appropriate range, and the taste obtained is better.

[0101] In Examples 1-3, the flow rate of the water vapor introduced into the dry distillation equipment is 400-600g / h, and the flow rate of the inert gas introduced is in the range of 100-130ml / min, which ensures a high yield. Finally, in the tasting test, the aroma and strength scores of Examples 1-3 are high, the irritation is small, so the irritation score is high, the aftertaste is good, and the total score is high. In particular, since the waste tobacco leaves of Example 2 are waste tobacco leaves that have been distilled by steam, the tobacco flavors obtained after such waste tobacco leaves are suitable for the extraction method of the present invention have a strong aroma sense and a good taste. This is because steam distillation can only extract free volatile aromatic components, while for the hard-to-volatize flavor precursors hemicellulose, cellulose, lignin, protein, pectin, etc., there is basically no loss, these components are better preserved, and more aroma substances are produced through pyrolysis and corresponding chemical reactions in the subsequent dry distillation process. At the same time, combined with the adsorption of the macroporous resin XAD-4 disclosed in the present invention and the recovery of the adsorbate with a volume fraction of 85%-95% ethanol, the final content of bad flavor substances is low. In addition, the heating rate is 5-6°C / min, and the flow rates of water vapor and nitrogen are within the range disclosed in the present invention, so that the final tobacco flavor substances have no bad flavor during the smoking process, the yield is high, and the roasted aroma and burnt sweet aroma are excellent in the smoking.

[0102] In Comparative Examples 1 and 2, the reaction temperature during the dry distillation process was set at 250°C, and the fractions in the temperature range of 200-250°C were collected, so the desired flavor products could not be obtained. In addition, the yield was very low, and the obtained tobacco flavors could not significantly improve the flavor and taste when added to cigarettes as additives.

[0103] Comparative Example 3 uses unextracted tobacco raw materials, and the dry distillation reaction temperature is low, and the material components obtained in the distillation dry distillation process are different from those in the embodiment. As shown in Table 3, the parent materials used in Comparative Examples 1, Comparative Examples 2 and Example 1 are different from those in Comparative Example 3, and the extraction methods of Example 1 and Comparative Examples 1 and 2 are different. Therefore, the main flavor substances in the tobacco flavor extracted after dry distillation and distillation are different from each other in composition and ratio between Comparative Examples 1-3 and Example 1.

[0104] Comparative Example 3 only uses the extraction method to extract tobacco flavors in the distillate. Finally, the content of benzopyrrole in the tobacco flavor obtained in Comparative Example 3 is increased, the yield is low, and the scores of various aspects in the tasting results are low.

[0105] Comparative Example 4 did not use the macroporous resin adsorption method of the present invention, but used the extraction method to extract the tobacco flavor in the distillate, so that the bad flavor substances were not effectively removed, especially benzopyrrole was not effectively removed, and the content of benzopyrrole in the obtained tobacco flavor was high, reaching 2.71%. The aroma and aftertaste were poor in the tasting results, the irritation was high, and the score was low.

[0106] In Comparative Example 5, since the volume fraction of ethanol used is lower than 85-95%, a better enrichment effect is not achieved for the aroma substances produced in the distillation-drying process of the waste tobacco leaves, resulting in excessive dispersion of the aroma substances in the ethanol solvent and a low aroma concentration. In addition, since the ethanol concentration is low and the water content is relatively high, further processing is required to add the ethanol solution containing the aroma components after extraction directly to the cigarette, such as drying, etc., resulting in reduced production efficiency, which is not conducive to the application of the extract in the product, and the subsequent cumbersome processing steps are also prone to cause the loss of aroma substances.

[0107] In Comparative Example 6, since the volume fraction of ethanol used is higher than 85-95%, the aroma substances and impurities are dissolved in the eluent too quickly, and it is impossible to separate different compounds by utilizing the different adsorption capacities of the macroporous resin for different substances. For example, benzopyrrole, which will produce a poor flavor at too high a concentration, cannot be separated from other aroma compounds in a high-concentration ethanol solution, resulting in a burnt odor in the final suction, and the overall suction result is relatively poor.

[0108] Since Comparative Example 7 uses tobacco raw materials instead of waste tobacco leaves, and there are differences in the composition of tobacco raw materials and waste tobacco leaves, the products after distillation-carbon distillation are also different.

[0109] In principle, the extraction method of the present invention is not only about the extraction of flavor substances, but also about chemical reactions during the dry distillation and distillation process, mainly the pyrolysis conversion of flavor precursors in tobacco, to generate specific flavor substances and their specific composition ratios. In Comparative Example 7, although the tobacco raw materials used have more flavor substances than the waste tobacco leaves, there are more free aromatic substances than the waste tobacco leaves, but these substances do not contribute much to the final tobacco flavor, which mainly lies in the reaction and extraction of flavor precursors in tobacco. The present invention is to extract the distillate and add it directly to the cigarette as an additive. The tobacco flavor extracted from the waste tobacco leaves is different in composition and ratio from the tobacco flavor obtained by the same method using the tobacco raw materials, so there will be differences in taste.

[0110] Through Comparative Example 7, it can be found that the extraction method of the present invention is more suitable for reaction and extraction of waste tobacco leaves. For the reaction and extraction of tobacco raw materials, the tobacco flavor components obtained are relatively complex. In the final tasting test, the score in terms of aroma is not high, and there is no advantage in other scores, and the final total score is low.

[0111] In addition, in the prior art, after steam distillation, supercritical CO2 extraction and petroleum ether extraction of tobacco leaf fragments, the waste tobacco leaves obtained generally need to undergo a series of subsequent treatments to become fertilizers, and the treatment process requires high costs. However, the mother material used in the present invention is waste tobacco leaves, and the cost of the raw materials themselves is relatively low. After the steam distillation-drying of the present invention, the remaining waste can be processed in a more cost-effective manner to become fertilizers, which simplifies the subsequent treatment method, reduces the subsequent treatment cost, and conforms to the social concept of green environmental protection.

[0112] Although the present invention has been illustrated and described with reference to certain preferred embodiments of the present invention, it should be understood by those skilled in the art that the above is a further detailed description of the present invention in conjunction with specific embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. Those skilled in the art may make various changes in form and details, including making several simple deductions or substitutions, without departing from the spirit and scope of the present invention.

Claims

1. A method for extracting tobacco flavor from waste tobacco leaves, characterized in that: include: Distillation-drying: adding waste tobacco leaves to a dry distillation device, introducing water vapor and inert gas into the dry distillation device, and heating the dry distillation device to a reaction temperature of 300-380° C. to simultaneously distill and dry distill the waste tobacco leaves; Collection: Collect the distillate distilled during the entire distillation-drying process; Elution and recovery: the distillate is adsorbed and eluted with a macroporous adsorption resin XAD-4 column, and the adsorbate is recovered with ethanol with a volume fraction of 85-95% to obtain an ethanol solution containing flavor components.

2. The method according to claim 1, characterized in that The flow rate of the water vapor introduced into the dry distillation equipment is 400-600 g / h, and the flow rate of the inert gas introduced into the dry distillation equipment is 100-130 ml / min.

3. The method according to claim 2, characterized in that The flow rate of the water vapor introduced is 500 g / h, and the flow rate of the inert gas introduced is 120 ml / min.

4. The method according to claim 1, characterized in that Before distillation and dry distillation, the dry distillation equipment is preheated to 60-80° C., and then the waste tobacco leaves are added.

5. The method according to claim 4, characterized in that After preheating, the heating rate from the preheating temperature to the reaction temperature is 5-6°C / min.

6. The method according to claim 1, characterized in that After reaching the reaction temperature, keep warm for 15 to 25 minutes.

7. The method according to claim 1, characterized in that After the collecting step, the distillate is filtered with filter paper and then the adsorption and elution step is performed.

8. The method according to claim 1, characterized in that The distillate was added to the XAD-4 column at an elution flow rate of 3-6 ml / min, and the desorption flow rate of the ethanol was 1-2 ml / min.

9. The method according to claim 8, characterized in that During the recovery process of the adsorbent by ethanol, one sample segment is collected every minute, and a total of 7 sample segments are collected. The 3rd to 6th sample segments are combined as the final ethanol solution containing aroma components.

10. The method according to claim 1, characterized in that After the adsorption and elution, the remaining liquid in the XAD-4 column is removed by pressurizing with compressed air, and then desorption is performed with the ethanol.

11. The method according to any one of claims 1 to 10, characterized in that: The waste tobacco leaves are tobacco waste materials remaining after the tobacco raw materials are subjected to steam distillation, supercritical CO2 extraction or organic solvent extraction of tobacco essential oil.

12. A flavor additive, characterized in that: The flavor additive comprises the ethanol solution directly obtained by the method for extracting tobacco flavor from waste tobacco leaves as described in any one of claims 1 to 11.

13. An aerosol generating substrate, characterized in that Contains the flavor additive as claimed in claim 12.

14. An aerosol generating article, characterized in that Contains the flavor additive as claimed in claim 12.

Images