A method of aging to reduce harshness and irritation of cigar tobacco

Abstract

The application discloses a kind of methods for reducing the pungency and irritation of cigar tobacco, belonging to the technical field of cigar processing.The method comprises the following steps: S1, dissolving the effective component in water to prepare a treatment solution;S2, evenly spray the treatment solution on the surface of cigar tobacco;S3, place the sprayed cigar tobacco in a constant temperature and humidity environment for equilibrium aging treatment to obtain improved cigar tobacco;Wherein, the effective component is organic acid and / or organic acid salt, and the organic acid and / or organic acid salt is selected from one or more of the following substances: malonic acid, succinic acid, potassium malonate, potassium succinate and potassium citrate.The application can significantly reduce the pungency and irritation of cigar tobacco by adding specific organic acids and organic acid salts exogenously, combined with optimized concentration, spraying amount and temperature and humidity conditions, improve aroma quality and quantity, improve aftertaste and overall sensory quality, and achieve the synergistic improvement effect of "increasing aroma, reducing irritation and reducing impurities".

Description

Technical Field

[0001] This patent belongs to the field of cigar processing technology, specifically relating to an aging treatment method for reducing the off-flavors and irritation of cigar tobacco leaves. Background Technology

[0002] The quality of cigar tobacco leaves is primarily determined by their sensory characteristics (such as aroma, off-flavors, and irritation) and chemical composition (such as nicotine, organic acids, and aromatic substances). Lower-grade cigar tobacco leaves generally suffer from insufficient aroma, excessive off-flavors, and high irritation, limiting their application in high-end cigar products. While existing technologies employ some methods of treating tobacco leaves with additives, such as enzymes, humectants, or certain salts, their effectiveness is limited, and there is a lack of optimized treatment schemes targeting organic acids and organic salts, making it impossible to simultaneously achieve the comprehensive goals of aroma enhancement, off-flavor reduction, and irritation improvement.

[0003] Currently, the closest existing technologies include methods that treat tobacco leaves with a single organic acid or inorganic salt, such as using citric acid or potassium salts for fermentation regulation. However, these methods have the following shortcomings: the treatment effect is unstable, and it cannot significantly increase the total amount of aroma components and key flavor substances; its ability to regulate nicotine release and the volatile organic acid spectrum is limited; the sensory improvement effect is not significant, and it is particularly difficult to simultaneously achieve a comprehensive style of "fragrant, sweet, mellow, clean, and smooth". Therefore, there is an urgent need for a systematic, efficient, and targeted tobacco quality improvement technology. Summary of the Invention

[0004] To solve the above-mentioned technical problems, this patent provides the following technical solution: On the one hand, a method for aging cigar tobacco leaves to reduce off-flavors and harshness is provided, comprising the following steps: S1. Dissolve the active ingredients in water to prepare a treatment solution; S2. Spray the treatment solution evenly onto the surface of the cigar tobacco leaves; S3. Place the sprayed cigar tobacco leaves in a constant temperature and humidity environment for balanced aging to obtain improved cigar tobacco leaves. The active ingredients are organic acids and / or organic acid salts, which are selected from one or more of the following substances: malonic acid, succinic acid, potassium malonic acid, potassium succinate, and potassium citrate.

[0005] Furthermore, the concentration of the effective component in the treatment solution is 0.05% to 0.5% by mass volume concentration, preferably 0.08% to 0.4%, more preferably 0.1% to 0.3%, and even more preferably 0.2%.

[0006] Furthermore, during the spraying process, the amount of the treatment solution sprayed is 1% to 20% of the tobacco leaf mass, preferably 3% to 15%, and more preferably 5% to 10%, by mass percentage.

[0007] Furthermore, the temperature for the equilibration aging process is 20℃~35℃, preferably 22℃~30℃, and even more preferably 24℃~28℃.

[0008] Furthermore, the relative humidity of the balancing aging treatment is 55% to 75%, preferably 60% to 70%, and even more preferably 63% to 68%.

[0009] Furthermore, the aging time is 24–120 hours, preferably 48–96 hours, and even more preferably 60–84 hours.

[0010] Furthermore, the cigar tobacco leaf is one or more of the following: cigar filler tobacco leaf, cigar binder tobacco leaf, or cigar wrapper tobacco leaf, preferably cigar filler tobacco leaf.

[0011] Furthermore, the treatment solution is a 0.2% (w / v) malonic acid or succinic acid solution.

[0012] Furthermore, the treatment solution is a potassium succinate solution with a mass-volume concentration of 0.2%.

[0013] In a second aspect, an improved cigar tobacco leaf is provided, which is obtained using the aging treatment method according to the first aspect.

[0014] The aging treatment method provided by this invention can significantly improve the sensory quality of cigar tobacco leaves. Cigar tobacco leaves treated by this method show a marked improvement in aroma quality and intensity, resulting in a smoother and more elegant smoke. Simultaneously, impurities and irritating components in the tobacco leaves are effectively reduced, leading to a purer and more comfortable smoking experience. Sensory evaluation results show that tobacco leaves treated using the preferred method of this invention are superior to untreated tobacco leaves in key sensory indicators such as aroma quality, aroma intensity, impurities, irritation, and aftertaste. The overall style and quality are significantly improved, achieving a synergistic improvement effect of "enhancing aroma, reducing irritation, and reducing impurities."

[0015] This invention enables targeted optimization of the chemical composition of cigar tobacco leaves. By exogenously adding specific organic acids and organic acid salts, the metabolic transformation of aroma precursors in the tobacco leaves is effectively regulated, promoting the accumulation of key aroma components such as petroleum ether extracts and volatile organic acids, thus providing a material basis for the richness and fullness of the smoke aroma. Simultaneously, this invention can regulate the release behavior of nicotine during combustion, effectively controlling the amount of nicotine released in the mainstream smoke, thereby reducing the physiological intensity of the smoke and making the smoking experience smoother and more comfortable. Attached Figure Description

[0016] The above content of this patent and the following detailed embodiments will be better understood when read in conjunction with the accompanying drawings. It should be noted that the drawings are merely examples of the claimed technical solution.

[0017] Figure 1 This is a schematic flowchart of an aging process according to an embodiment of the present invention. Detailed Implementation

[0018] The detailed features and advantages of this application are described below in the specific embodiments. The content of this description is sufficient to enable any person skilled in the art to understand the technical content of this application and implement it accordingly. Based on the specification, claims and drawings disclosed in this specification, a person skilled in the art can easily understand the related objectives and advantages of this application.

[0019] In this specification and claims, several terms will be used, and unless otherwise indicated, these terms will be defined to have the following meanings: All figures used to represent component amounts, properties (e.g., weight-average molecular weight), reaction conditions, etc., should be considered to be modified in all cases by the terms "within the unavoidable margin of error" or "approximately". Therefore, the numerical values ​​presented herein are approximate and may vary depending on the desired properties sought to be obtained by this patent. The principle of equivalents, which is applied to a minimum and not intended to limit the scope of the claims, should be applied, for example, each value should be interpreted at least according to the reported significant digits and by applying conventional rounding techniques.

[0020] All other terms used herein for special definition are intended to have the general meaning understood by one of ordinary skill in the art, and in particular, meaning that one of ordinary skill in the art, upon reading the claims, specification and drawings of this patent, can directly and without doubt determine how the technical solution of this patent can be implemented.

[0021] Even if there are incomplete descriptions, omissions, or ambiguities in the grammar, words, punctuation, graphics, symbols, etc. of the claims, specification, and drawings of this patent, a person skilled in the art can still arrive at the only correct understanding by reading the claims, specification, and drawings as a whole without extensive reasoning or experimentation, and effectively exclude various incorrect interpretations that are not aimed at achieving the purpose of this patent.

[0022] The "range" disclosed herein is defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of a particular range. Ranges defined in this way can include or exclude endpoints and can be arbitrarily combined; that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60-120 and 80-110 are listed for a specific parameter, it is expected that ranges of 60-110 and 80-120 are also expected. Furthermore, if minimum range values ​​of 1 and 2 are listed, and if maximum range values ​​of 3, 4, and 5 are listed, then the following ranges are all expected: 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5. In this application, unless otherwise stated, the numerical range "ab" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0-5" indicates that all real numbers between "0-5" have been listed in this article; "0-5" is simply a shortened representation of these numerical combinations. Furthermore, when a parameter is stated as an integer ≥2, it is equivalent to disclosing that the parameter is, for example, an integer such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0023] Unless otherwise specified, all embodiments and preferred embodiments mentioned herein can be combined to form new technical solutions.

[0024] Unless otherwise specified, all the technical features and preferred features mentioned herein can be combined to form new technical solutions.

[0025] Unless otherwise specified, all steps mentioned herein may be performed sequentially or randomly, but are preferably performed sequentially. For example, the method includes steps (a) and (b), indicating that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, the mention that the method may also include step (c) indicates that step (c) may be added to the method in any order; for example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.

[0026] Unless otherwise specified, the terms "comprising" and "including" as used herein can be open-ended or closed-ended. For example, "comprising" and "including" may mean that other components not listed may also be included, or that only the listed components may be included.

[0027] In the description of this article, it should be noted that, unless otherwise stated, "above" and "below" include the number itself, and "several" in "one or more" means two or more.

[0028] In this description, unless otherwise stated, the term "or" is inclusive. For example, the phrase "A or B" means "A, B, or both A and B". More specifically, the condition "A or B" is satisfied by any of the following conditions: A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or both A and B are true (or exist).

[0029] Unless otherwise specified, percentages (%) in this document refer to percentages by mass relative to the composition.

[0030] Unless otherwise stated herein, the sum of the contents of the components in the composition is 100%.

[0031] In this document, unless otherwise stated, “combination of” means a multi-component mixture of the elements, such as two, three, four, and up to the maximum possible multi-component mixture.

[0032] Unless otherwise specified, the term "a" as used in this specification means "at least one".

[0033] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0035] To make the objectives, technical solutions, and advantages of this invention clearer, the embodiments of this invention will be described in further detail below. Unless otherwise specified, the experimental methods described in the embodiments of this invention are conventional methods, and the materials and reagents used in the following embodiments are commercially available unless otherwise specified.

[0036] One object of the present invention is to provide an aging treatment method for reducing the off-flavors and irritation of cigar tobacco leaves, comprising the following steps: S1. Dissolve the active ingredients in water to prepare a treatment solution; S2. Spray the treatment solution evenly onto the surface of the cigar tobacco leaves; S3. Place the sprayed cigar tobacco leaves in a constant temperature and humidity environment for balanced aging to obtain improved cigar tobacco leaves. The active ingredients are organic acids and / or organic acid salts, which are selected from one or more of the following substances: malonic acid, succinic acid, potassium malonic acid, potassium succinate, and potassium citrate.

[0037] In some embodiments, the concentration of the active ingredient in the treatment solution is 0.05% to 0.5% by mass volume, preferably 0.08% to 0.4%, more preferably 0.1% to 0.3%, and even more preferably 0.2%.

[0038] As used in this article, "w / v" refers to the percentage of solute mass to solution volume, such as 1 g / 100 mL, which is expressed as 1%.

[0039] In some embodiments, during the spraying process, the amount of the treatment solution sprayed is 1% to 20% of the tobacco leaf mass, preferably 3% to 15%, and more preferably 5% to 10%, by mass percentage. As used herein, mass percentage refers to the percentage of the solute mass to the total solution mass.

[0040] As used in this article, "balanced aging" refers to placing tobacco leaves in a constant temperature and humidity environment for a period of time after spraying the treatment solution, allowing the treatment solution to fully penetrate into the tobacco leaves, and activating the endogenous enzymatic reactions of the tobacco leaves under stable temperature and humidity conditions, promoting the interaction between exogenous additives and tobacco leaf components, thereby generating aroma substances, transforming irritating components and stabilizing the moisture content of tobacco leaves. It is a key process step to achieve the synergistic improvement effect of "enhancing aroma, reducing irritation and reducing impurities".

[0041] In some embodiments, the temperature for the equilibration aging process is 20°C to 35°C, preferably 22°C to 30°C, and more preferably 24°C to 28°C.

[0042] In some embodiments, the relative humidity of the balancing aging treatment is 55% to 75%, preferably 60% to 70%, and more preferably 63% to 68%.

[0043] In some embodiments, the aging time is 24 to 120 hours, preferably 48 to 96 hours, and more preferably 60 to 84 hours.

[0044] In some embodiments, the cigar tobacco is one or more of the following: cigar filler tobacco, cigar binder tobacco, or cigar wrapper tobacco, preferably cigar filler tobacco.

[0045] In a preferred embodiment, the treatment solution is a malonic acid or succinic acid solution with a mass-volume concentration of 0.2%.

[0046] In a preferred embodiment, the treatment solution is a potassium succinate solution with a mass-volume concentration of 0.2%.

[0047] Another object of the present invention is to provide an improved cigar tobacco leaf obtained by the aging treatment method according to the present invention.

[0048] Example

[0049] Experimental materials

[0050] The tobacco leaves used for the test cigars were selected from the middle section of the "Chu Xue 14" variety produced in Danjiangkou, Shiyan, Hubei Province in 2024, and were provided by Hubei China Tobacco Industry Co., Ltd. The tobacco leaves were grade three in appearance, and the initial moisture content was controlled between 13% and 15%.

[0051] Chemical reagents: malonic acid (analytical grade, purity ≥99.5%), succinic acid (analytical grade, purity ≥99.5%), potassium malonate (analytical grade, purity ≥99%), potassium succinate (analytical grade, purity ≥99%), and potassium citrate (analytical grade, purity ≥99%), all purchased from Guangzhou Deli Chemical Co., Ltd.

[0052] Experimental equipment: constant temperature and humidity incubator (HWS-150B type, Shanghai Bilang Instrument Manufacturing Co., Ltd.), handheld sprayer (1.5L, commercially available), electronic balance (accuracy 0.001g), moisture analyzer.

[0053] Example 1

[0054] Weigh 1.0 g of potassium malonate and dissolve it in 999 mL of deionized water. Stir thoroughly until completely dissolved to prepare a potassium malonate treatment solution with a mass-volume concentration of 0.1%. Prepare and use immediately.

[0055] Take 10 kg of the above-mentioned tobacco leaves and spread them evenly on a clean work surface. Fill a handheld sprayer with the prepared potassium malonate treatment solution and adjust the nozzle to ensure even atomization. Apply the treatment solution evenly to the surface of the tobacco leaves using a "small amount, multiple times" spraying method, with the application amount being 10% of the tobacco leaf mass (approximately 100g of solution per kilogram of tobacco leaves). During spraying, continuously turn the tobacco leaves to ensure that both sides are evenly wetted and that there are no obvious droplets running down the surface.

[0056] After spraying, the tobacco leaves were loosely piled in a well-ventilated stainless steel mesh tray, with a thickness not exceeding 10 cm, and immediately transferred to a constant temperature and humidity incubator. The conditions were set as follows: temperature 25℃±1℃, relative humidity 65%±3%. Under these conditions, the tobacco was aged for 72 hours.

[0057] Comparative Example 1 & Examples 2-15

[0058] Following the same procedure as in Example 1, the following table shows the processing methods used to obtain Comparative Example 1 (blank control group) and Examples 2-15: Table 1. Composition and concentration of the treatment solutions in Comparative Example 1 and Examples 2-15

[0059] Test Example 1

[0060] This experiment determined the content of petroleum ether extract in cigar tobacco leaves to reflect changes in their aroma compounds. The testing procedure is as follows: Sample preparation followed the method in standard YC / T31—1996. After curing, the tobacco leaf samples were dried in an oven at 40℃ for 3–4 h until they could be crushed by fingers. After cooling and pulverizing, the samples were passed through a 40-mesh sieve and stored in a vacuum bag for later use. The petroleum ether extraction rate was determined according to standard YC / T 176—2003, "Determination of Petroleum Ether Extracts in Tobacco and Tobacco Products". The extracted petroleum ether extract was concentrated to 1 mL using a rotary evaporator and stored for later use.

[0061] The test results are shown in Table 2: Table 2. Results of the determination of petroleum ether extract content

[0062] Compared with Comparative Example 1 (blank control), the extract contents of all treatments except for those with potassium malonate 0.1%, potassium malonate 0.3%, potassium succinate 0.2%, potassium citrate 0.2%, and succinic acid 0.3% were significantly increased. Among them, the increases were most significant in the potassium succinate 0.3% and potassium citrate 0.1% groups, which were 42% and 40% higher than the control, respectively.

[0063] Test Example 2

[0064] This experiment measured the nicotine release from mainstream cigarette smoke to reflect the nicotine content in cigarette samples treated with different methods. The testing procedure was as follows: A cigarette was smoked on a cigar smoking machine, and total particulate matter was collected using a Cambridge filter smoke trap. The mass of the total particulate matter was weighed. The extracted total particulate matter was used for gas chromatography to determine the moisture and nicotine content.

[0065] The test results are shown in Table 3: Table 3. Experimental results of nicotine release from mainstream flue gas

[0066] Analysis of mainstream flue gas nicotine release using Cambridge filters revealed that exogenous potassium salts generally had a significant inhibitory effect. Specifically, the nicotine release in the treatment groups with 0.2% potassium malonate, 0.1% and 0.3% potassium succinate, and 0.1% to 0.3% potassium citrate was more than 75% lower than the control, demonstrating a particularly prominent inhibitory effect; potassium succinate showed extremely low release at all concentrations. In contrast, the two organic acids had opposite effects: malonic acid at 0.3% released as much as 4.21 mg / g, 3.5 times that of the control; while succinic acid release steadily increased with increasing concentration, reaching 3 times that of the control at 0.3%. Overall, potassium ions may promote nicotine decomposition by altering the combustion process, thereby significantly reducing its transfer to flue gas.

[0067] Test Example 3

[0068] The sensory evaluation process is as follows: The tobacco leaves from Comparative Example 1, Example 2, Example 5, Example 9, Example 11, and Example 14 were taken out and placed in an environment with a temperature of 22°C and a relative humidity of 60% for 24 hours to rehydrate and equilibrate, so that the moisture content of the tobacco leaves was adjusted to 16%±1%. The tobacco leaves were rolled into standard-sized cigars (120mm in length and 42mm in ring gauge) by hand, with 50 cigars rolled per process, and placed in a constant temperature and humidity chamber for equilibration for 7 days before use.

[0069] A seven-member evaluation team was formed from the Technical Center of Hubei Tobacco Industry Co., Ltd. The evaluation indicators included: aroma quality, aroma intensity, off-flavors (higher scores indicate less off-flavors), irritation (higher scores indicate less irritation), aftertaste, sweetness, flammability, and ash color. Each indicator had three sub-categories, and the average value was used as the final score. The results are shown in the table below: Table 4 Sensory Evaluation Results A

[0070] The evaluation indicators also include: concentration, intensity, style level, and quality grade. Each indicator has a maximum score of 5, and the average value is taken as the final score. The results are shown in the table below: Table 5 Sensory Evaluation Results B

[0071] Sensory evaluation results showed that 0.2% malonic acid and 0.2% succinic acid performed best overall, both scoring 80 points, significantly improving the style and quality of the cigars, especially in reducing off-flavors and harshness, and enhancing overall comfort. Potassium salt treatment showed mixed results: 0.2% potassium succinate performed well, maintaining aroma while making the taste smoother and achieving a high quality level; while 0.2% potassium malonic acid and 0.2% potassium citrate scored close to the control, showing limited improvement. All treatments had no significant effect on combustibility, ash color, or sweetness.

[0072] In the foregoing description of exemplary embodiments / specific implementations of this patent, various features of this patent are sometimes combined in a single embodiment / specific implementation or its figures and description, with the aim of simplifying the disclosure and aiding in the understanding of one or more of the various aspects of the invention. However, unless expressly stated otherwise or in obvious technical contradiction or exclusion, the descriptive method of this patent should not be construed as reflecting an intention that the claimed features of the invention are more than expressly stated in each claim. Rather, the inventive aspect reflected in the claims lies in not all the features of a single foregoing disclosed embodiment / specific implementation. Therefore, the claims following the detailed description are hereby expressly incorporated into this detailed description, each claim existing independently as a separate embodiment / specific implementation of this patent.

[0073] The terms and expressions used in this specification are for illustrative purposes and not for limitation. Their use is not intended to exclude any equivalents of the shown and described features or portions thereof, but rather to facilitate the understanding that various modifications may be possible within the scope of this patent claim. Therefore, it should be understood that while this patent has been specifically disclosed through preferred embodiments, exemplary embodiments, and optional features, variations or modifications of the concepts disclosed herein may be adopted by those skilled in the art, and such variations and modifications are therefore considered to be within the scope of this patent as defined by the appended claims. The specific embodiments given in this specification are examples of useful embodiments of this patent, and it will be apparent to those skilled in the art that this patent can be implemented using many variations of the devices, device components, and method steps disclosed herein.

[0074] The foregoing description of specific embodiments fully discloses the general features of this patent, enabling others to easily modify and / or adapt such embodiments for various applications by applying knowledge within the scope of the art, without excessive experimentation or deviation from the general concept of this patent. Therefore, based on the teachings and guidance provided herein, it is intended that such modifications and alterations be included within the meaning and scope of equivalents of the disclosed embodiments. It should be understood that the wording or terminology used herein is for descriptive purposes and not intended to be limiting; thus, the wording or terminology in this specification will be interpreted by those skilled in the art based on the foregoing teachings and guidance.

[0075] Furthermore, the scope of this patent should not be limited to any of the exemplary embodiments described above, but only to the appended claims and their equivalents.

Claims

1. A method for aging cigar tobacco leaves to reduce off-flavors and irritation, characterized in that, Includes the following steps: S1. Dissolve the active ingredients in water to prepare a treatment solution; S2. The treatment solution is evenly sprayed onto the surface of the cigar tobacco leaves; S3. Place the sprayed cigar tobacco leaves in a constant temperature and humidity environment for balanced aging to obtain improved cigar tobacco leaves. The active ingredient is an organic acid and / or an organic acid salt, which is selected from one or more of the following substances: malonic acid, succinic acid, potassium malonic acid, potassium succinate, and potassium citrate.

2. The aging treatment method according to claim 1, characterized in that, The concentration of the active ingredient in the treatment solution is 0.05% to 0.5% by mass volume, preferably 0.08% to 0.4%, more preferably 0.1% to 0.3%, and even more preferably 0.2% by mass volume.

3. The aging treatment method according to claim 2, characterized in that, During the spraying process, the amount of the treatment solution sprayed is 1% to 20% of the mass of the cigar tobacco leaves, preferably 3% to 15%, and more preferably 5% to 10%, by mass percentage.

4. The aging treatment method according to claim 3, characterized in that, The temperature for the balancing aging process is 20℃~35℃, preferably 22℃~30℃, and more preferably 24℃~28℃.

5. The aging treatment method according to claim 4, characterized in that, The relative humidity of the balancing aging treatment is 55% to 75%, preferably 60% to 70%, and more preferably 63% to 68%.

6. The aging treatment method according to claim 5, characterized in that, The aging time is 24 to 120 hours, preferably 48 to 96 hours, and more preferably 60 to 84 hours.

7. The aging treatment method according to claim 6, characterized in that, The cigar tobacco leaves are one or more of the following: cigar filler tobacco leaves, cigar binder tobacco leaves, or cigar wrapper tobacco leaves, preferably cigar filler tobacco leaves.

8. The aging treatment method according to claim 1, characterized in that, The treatment solution is a 0.2% (w / v) malonic acid or succinic acid solution.

9. The aging treatment method according to claim 1, characterized in that, The treatment solution is a potassium succinate solution with a mass-volume concentration of 0.2%.

10. An improved cigar tobacco leaf obtained by the aging treatment method according to any one of claims 1-9.

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