Method for making dark brown cigar wrapper

Abstract

The present invention relates to the technical field of cigar processing and discloses a method for producing a dark brown cigar wrapper. Sun-grown cigar wrapper tobacco leaves are relatively thick, and while direct rehydration using conventional methods can achieve ideal rehydration results, the moisture content after rehydration is poorly uniform, hindering uniform color change in the leaves. The present invention sequentially performs a primary vacuum treatment, rehydration of the leaves, stacking, fermentation, a secondary vacuum treatment, and low-temperature drying to produce a dark brown cigar wrapper with excellent color uniformity. Specifically, the present invention vacuum treats the tobacco leaves before and after fermentation to achieve uniform color change.

Description

Technical Field

[0001] The invention relates to the technical field of cigar processing, and in particular to a method for making a dark brown cigar wrapper. Background Art

[0002] Cigar sales have skyrocketed in recent years, with handmade cigars, as a high-end, personalized consumer product, experiencing particularly strong demand. Handmade cigars are crafted entirely by hand from cigar leaves, each divided into three layers: filler, binder, and wrapper. The filler and binder largely determine the flavor of the cigar, while the outermost layer, the wrapper, directly influences its appearance. High-quality cigars feature wrappers with a uniform color, fine veins, and ample oil content, conveying a premium feel.

[0003] Internationally, cigar wrapper tobacco leaves are divided into seven colors: green-brown, yellow-brown, light brown, medium brown, reddish-brown, dark brown, and nearly black. Generally speaking, the darker the color of the cigar wrapper, the richer and longer-lasting sweetness it can provide, the fuller flavor and richer aroma it has, and the smoother and smoother taste experience it brings. In addition, dark brown cigar wrappers give people a mature and rich feeling, and are deeply sought after by cigar lovers. For this reason, the research on the production method of dark brown cigar wrappers has also become a hot research topic for various cigar industry enterprises.

[0004] After conventional processing, the wrapper typically turns light brown to medium brown. The preparation of dark brown wrappers requires specialized processing, and this remains a major technical challenge in the cigar industry. Currently, research on dark brown wrapper preparation methods is limited. Prior art Chinese patent application publication number CN109645551A discloses a method for making dark brown cigar wrappers. The method involves soaking the petiole ends of sun-cured, upper-second-shed wrapper tobacco leaves in a compound solution for 10-30 minutes. The compound solution is then sprayed onto the leaves to adjust their moisture content to 30-40%. The leaves are then neatly stacked to a height of 0.3-0.6 meters. A pressure of 75-100 N is applied to the pile, and the leaves are fermented under ambient conditions of 35-55°C and 70-83% relative humidity. The moisture content of the tobacco pile is monitored every 5-8 days. When the moisture content is less than 25%, the pile is humidified to maintain a moisture content of 25-35% and continue fermentation. Fermentation is completed in 50-70 days. However, the method provided by this patent has the following problems: the tobacco leaves used to make dark brown wrappers are relatively thick, and direct rehydration after soaking the stems will result in unsatisfactory rehydration effect and poor moisture uniformity, which is not conducive to uniform color change of the tobacco leaves. Summary of the Invention

[0005] Existing dark brown cigar wrappers suffer from poor color uniformity. To address this issue, the present invention provides a method for producing a dark brown cigar wrapper. The method sequentially performs a primary vacuum treatment, tobacco leaf conditioning, stacking, fermentation, a secondary vacuum treatment, and low-temperature drying to produce a dark brown cigar wrapper with excellent color uniformity.

[0006] The specific technical solutions of the present invention are:

[0007] In a first aspect, the present invention provides a method for producing a dark brown cigar wrapper. The method uses sun-grown cigar wrapper tobacco leaves from the upper second shed as raw material and performs the following steps:

[0008] Step S1: Perform a vacuum treatment to make the moisture content of the tobacco leaves uniform;

[0009] Step S2: rehumidifying the tobacco leaves to a moisture content of 45-50%;

[0010] Step S3, stacking the tobacco leaves to obtain a stack with a height of 1.1 to 1.3 m;

[0011] Step S4, performing fermentation treatment, during which the temperature of the core is kept at 33-56° C.;

[0012] Step S5: performing a secondary vacuum treatment to make the moisture content of the tobacco leaves uniform;

[0013] Step S6: placing the tobacco leaves in a low temperature environment to reduce the moisture content of the tobacco leaves to below 25%.

[0014] Sun-grown cigar wrappers are thicker, and while direct conditioning by conventional methods may achieve ideal conditioning, moisture uniformity after conditioning is poor, hindering uniform color change. The present invention achieves a dark brown cigar wrapper with excellent color uniformity by sequentially performing a primary vacuum treatment, conditioning, stacking, fermentation, a secondary vacuum treatment, and low-temperature drying. Specifically, the present invention vacuum treats the tobacco leaves before and after fermentation to achieve uniform color change.

[0015] The vacuum treatment is carried out in a rehumidification chamber. The chamber is evacuated to a certain vacuum level and the tobacco leaves are treated for a certain period of time. This can improve the uniformity of moisture content in the tobacco leaves, which is conducive to uniform color change. During the vacuum treatment process, water mist can also be sprayed into the rehumidification chamber to increase the moisture content of the tobacco leaves by 2-4%, softening the leaves and facilitating the infiltration of moisture into the leaves during the subsequent rehumidification process. This will make the moisture content of the tobacco leaves uniform, improve the fermentation effect, and achieve uniform color change.

[0016] To further improve the color uniformity of the wrapper's surface, the core temperature during fermentation needs to be controlled between 33 and 56°C. Tobacco leaf fermentation often requires a high moisture content to better facilitate chemical reactions and produce the tobacco's aroma and taste. However, high moisture content makes tobacco leaves susceptible to mold, which prevents uniform color change. Therefore, the present invention requires controlling the core temperature during fermentation within the range of 33 to 56°C. If the core temperature is below 33°C, tobacco leaf fermentation is hindered, resulting in poor nicotine conversion. If the core temperature is above 56°C, mold is evident, resulting in a mottled appearance on the wrapper's surface.

[0017] At the same time, the present invention also requires controlling the height of the tobacco leaf stack to 1.1 to 1.3 meters. Tobacco leaves transform into a dark brown color, they must produce a certain amount of melanin. By stacking the tobacco leaves at a relatively high height of 1.1 to 1.3 meters, the present invention places the stack under greater pressure, prompting the tobacco leaves to produce melanin, causing them to transform into a dark brown color. If the stack height is less than 1.1 meters, the resulting tobacco leaves are lighter in color and do not meet the dark brown requirement. If the stack height is greater than 1.3 meters, the tobacco leaves are subjected to excessive pressure, which is not conducive to fermentation.

[0018] Preferably, in step S4, when the temperature exceeds 56°C, stacking is performed.

[0019] Preferably, in step S4, the temperature of the core is kept at 40-50°C during fermentation.

[0020] During fermentation, the core temperature should be kept between 40 and 50°C, so that the color uniformity of the wrapper surface is optimal.

[0021] Preferably, in step S4, the fermentation treatment environment is in a high humidity state, and the relative humidity of the high humidity environment is 75-80%.

[0022] Fermentation is carried out in a high humidity environment, which is conducive to the fermentation effect and the transformation of tobacco leaves into dark brown.

[0023] More preferably, the fermentation treatment environment is at 25-30°C.

[0024] Preferably, in step S1, the vacuum treatment method is: placing the tobacco leaves in an environment with a vacuum degree not greater than -85 kPa and a temperature of 60 to 70° C., and leaving it to stand for 10 to 15 minutes.

[0025] Preferably, in step S5, the vacuum treatment method is: placing the tobacco leaves in an environment with a vacuum degree not greater than -98 kPa and a temperature of 60 to 70° C., and leaving it to stand for 10 to 15 minutes.

[0026] Preferably, in step S6, the temperature of the low-temperature environment is 0-5°C.

[0027] After fermentation, the moisture in tobacco leaves contains certain precursors that can be converted into melanin. If dried directly in a high-temperature environment, the moisture will be lost faster. These precursors will be transferred to the surface of the tobacco leaves along with the moisture and will be oxidized at a faster rate to produce melanin, which can easily cause the surface of the tobacco leaves to become mottled.

[0028] More preferably, in step S6, the time of being placed in the low temperature environment does not exceed 20 days.

[0029] Preferably, in step S2, the water used for moisturizing the tobacco leaves is tobacco stem water, and the preparation method of the tobacco stem water is: take the tobacco stems produced during the preparation process, add 90-100°C water at a mass ratio of 1:10-15, soak for 10-16 hours, and filter to obtain the water.

[0030] Compared with the prior art, the advantages and beneficial effects of the present invention are as follows:

[0031] (1) The present invention sequentially performs a primary vacuum treatment, tobacco leaf conditioning, stacking, fermentation, a secondary vacuum treatment, and low-temperature drying to produce a dark brown cigar wrapper with uniform color. In particular, the present invention vacuum treats the tobacco leaves before and after fermentation to achieve uniform color change.

[0032] (2) To further improve the color uniformity of the wrapper surface, the present invention requires controlling the core temperature during fermentation within the range of 33-56°C. The present invention prevents mildew by controlling the fermentation temperature of tobacco leaves. This method is simple and has good industrial prospects.

[0033] (3) The present invention stacks tobacco leaves to a relatively high height of 1.1 to 1.3 m, placing the stack under relatively high pressure, thereby prompting the tobacco leaves to produce melanin and turning the tobacco leaves into dark brown, thereby avoiding the application of external pressure and improving production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 1 is a comparison chart of the cigar wrappers prepared in Comparative Examples 1 to 4 and Example 1.

[0035] In the figure: from left to right, the wrappers are those obtained in Example 1 and Comparative Examples 1 to 4. DETAILED DESCRIPTION

[0036] The present invention will be further described below with reference to the following embodiments. Those skilled in the art will be able to implement the present invention based on these descriptions. Furthermore, the embodiments of the present invention described below are generally only a portion of the embodiments of the present invention, rather than all of the embodiments. Therefore, all other embodiments derived by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

[0037] Example 1

[0038] This embodiment provides a dark brown cigar wrapper with good color uniformity, and the preparation method includes the following steps:

[0039] Step S1: Place tobacco leaves in a dehumidification chamber, adjust the chamber temperature to 65°C, and evacuate to -85kPa. Maintain the vacuum in the chamber at -85kPa for 10 minutes. When the vacuum in the chamber reaches a preset value, spray a fine mist of water into the chamber to increase the moisture content of the tobacco leaves by 3%. The tobacco leaves achieve uniform moisture content in the -85kPa vacuum.

[0040] Step S2: Moisturizing the tobacco leaves by spraying, sealing the leaves in plastic bags, and conducting moisture balance in an environment of 30° C. for 40 hours, so that the moisture content of the tobacco leaves reaches 47%.

[0041] The water used for moistening is tobacco stem water. The tobacco stem water is prepared by adding 100°C water to the tobacco stems produced during the preparation process at a mass ratio of 1:15, soaking for 10 hours, and filtering the water.

[0042] Step S3: stack the tobacco leaves with the leaf tips facing inward and the leaf bases facing outward. The length and width of the tobacco stack are 1.4 m and the height is 1.2 m. After stacking, the surface of the tobacco stack is covered with cotton cloth.

[0043] Step S4: placing the tobacco pile in a temperature- and humidity-controlled environment for fermentation at 25° C. and 78% relative humidity. When the core temperature of the pile exceeds 56° C., the pile is turned over to maintain the core temperature between 33° C. and 56° C. for fermentation for a total of 46 days. If the core temperature does not exceed 56° C., the pile is turned over once every 10 days.

[0044] Step S5: Perform a secondary vacuum treatment to make the moisture content of the tobacco leaves uniform. The method is the same as step S1, except that the vacuum degree is -95kPa and no water mist is sprayed for moistening.

[0045] Step S6: Place the tobacco leaves in a 0°C environment and let them stand for 17 days until the moisture content of the tobacco leaves reaches 23%.

[0046] After the above steps S1 to S6, this embodiment obtains a dark brown cigar wrapper with good color uniformity.

[0047] Example 2

[0048] This embodiment provides a dark brown cigar wrapper with good color uniformity, and the preparation method includes the following steps:

[0049] Step S1: Place tobacco leaves in a rehumidification chamber, adjust the chamber temperature to 65°C, and evacuate to -85kPa. Maintain the vacuum in the chamber at -85kPa for 10 minutes. When the vacuum in the chamber reaches a preset value, spray a fine mist of water into the chamber to increase the moisture content of the tobacco leaves by 2%. The tobacco leaves achieve uniform moisture content in the -85kPa vacuum.

[0050] Step S2: Moisturizing the tobacco leaves by spraying, sealing the leaves in plastic bags, and conducting moisture balance in an environment of 30° C. for 40 hours, so that the moisture content of the tobacco leaves reaches 47%.

[0051] The water used for moistening is tobacco stem water. The tobacco stem water is prepared by adding 100°C water to the tobacco stems produced during the preparation process at a mass ratio of 1:15, soaking for 10 hours, and filtering the water.

[0052] Step S3: stack the tobacco leaves with the leaf tips facing inward and the leaf bases facing outward. The length and width of the tobacco stack are 1.4 m and the height is 1.2 m. After stacking, the surface of the tobacco stack is covered with cotton cloth.

[0053] Step S4: placing the tobacco pile in a temperature- and humidity-controlled environment for fermentation at 25° C. and 78% relative humidity. When the core temperature of the pile exceeds 56° C., the pile is turned over to maintain the core temperature between 33° C. and 56° C. for fermentation for a total of 46 days. If the core temperature does not exceed 56° C., the pile is turned over once every 10 days.

[0054] Step S5: Perform a secondary vacuum treatment to make the moisture content of the tobacco leaves uniform. The method is the same as step S1, except that the vacuum degree is -95kPa and no water mist is sprayed for moistening.

[0055] Step S6: Place the tobacco leaves in a 0°C environment and let them stand for 17 days until the moisture content of the tobacco leaves reaches 23%.

[0056] After the above steps S1 to S6, this embodiment obtains a dark brown cigar wrapper with good color uniformity.

[0057] Example 3

[0058] This embodiment provides a dark brown cigar wrapper with good color uniformity, and the preparation method includes the following steps:

[0059] Step S1: Place tobacco leaves in a rehumidification chamber, adjust the chamber temperature to 65°C, and evacuate to -85kPa. Maintain the vacuum in the chamber at -85kPa for 10 minutes. When the vacuum in the chamber reaches a preset value, spray a fine mist of water into the chamber to increase the moisture content of the tobacco leaves by 4%. The tobacco leaves achieve uniform moisture content in the -85kPa vacuum.

[0060] Step S2: Moisturizing the tobacco leaves by spraying, sealing the leaves in plastic bags, and conducting moisture balance in an environment of 30° C. for 40 hours, so that the moisture content of the tobacco leaves reaches 47%.

[0061] The water used for moistening is tobacco stem water. The tobacco stem water is prepared by adding 100°C water to the tobacco stems produced during the preparation process at a mass ratio of 1:15, soaking for 10 hours, and filtering the water.

[0062] Step S3: stack the tobacco leaves with the leaf tips facing inward and the leaf bases facing outward. The length and width of the tobacco stack are 1.4 m and the height is 1.2 m. After stacking, the surface of the tobacco stack is covered with cotton cloth.

[0063] Step S4: placing the tobacco pile in a temperature- and humidity-controlled environment for fermentation at 25° C. and 78% relative humidity. When the core temperature of the pile exceeds 56° C., the pile is turned over to maintain the core temperature between 33° C. and 56° C. for fermentation for a total of 46 days. If the core temperature does not exceed 56° C., the pile is turned over once every 10 days.

[0064] Step S5: Perform a secondary vacuum treatment to make the moisture content of the tobacco leaves uniform. The method is the same as step S1, except that the vacuum degree is -95kPa and no water mist is sprayed for moistening.

[0065] Step S6: Place the tobacco leaves in a 0°C environment and let them stand for 17 days until the moisture content of the tobacco leaves reaches 23%.

[0066] After the above steps S1 to S6, this embodiment obtains a dark brown cigar wrapper with good color uniformity.

[0067] Example 4

[0068] This embodiment provides a dark brown cigar wrapper with good color uniformity, and the preparation method includes the following steps:

[0069] Step S1: Place tobacco leaves in a rehumidification chamber, adjust the chamber temperature to 65°C, evacuate to -85kPa, and maintain the vacuum degree at -85kPa for 10 minutes. The tobacco leaves achieve uniform moisture content in a vacuum degree of -85kPa.

[0070] Step S2: Moisturizing the tobacco leaves by spraying, sealing the leaves in plastic bags, and conducting moisture balance in an environment of 30° C. for 40 hours, so that the moisture content of the tobacco leaves reaches 47%.

[0071] The water used for moistening is tobacco stem water. The tobacco stem water is prepared by adding 100°C water to the tobacco stems produced during the preparation process at a mass ratio of 1:15, soaking for 10 hours, and filtering the water.

[0072] Step S3: stack the tobacco leaves with the leaf tips facing inward and the leaf bases facing outward. The length and width of the tobacco stack are 1.4 m and the height is 1.2 m. After stacking, the surface of the tobacco stack is covered with cotton cloth.

[0073] Step S4: placing the tobacco pile in a temperature- and humidity-controlled environment for fermentation at 25° C. and 78% relative humidity. When the core temperature of the pile exceeds 56° C., the pile is turned over to maintain the core temperature between 33° C. and 56° C. for fermentation for a total of 46 days. If the core temperature does not exceed 56° C., the pile is turned over once every 10 days.

[0074] Step S5: Perform a secondary vacuum treatment to make the moisture content of the tobacco leaves uniform. The method is the same as step S1, except that the vacuum degree is -95kPa and no water mist is sprayed for moistening.

[0075] Step S6: Place the tobacco leaves in a 0°C environment and let them stand for 17 days until the moisture content of the tobacco leaves reaches 23%.

[0076] After the above steps S1 to S6, this embodiment obtains a dark brown cigar wrapper with good color uniformity.

[0077] Example 5

[0078] This embodiment provides a dark brown cigar wrapper with good color uniformity, and the preparation method includes the following steps:

[0079] Step S1: Place tobacco leaves in a rehumidification chamber, adjust the chamber temperature to 65°C, and evacuate to -95kPa. Maintain the vacuum in the chamber at -95kPa for 10 minutes. When the vacuum in the chamber reaches a preset value, spray a fine mist of water into the chamber to increase the moisture content of the tobacco leaves by 3%. This achieves uniform moisture content in the tobacco leaves under a vacuum of -95kPa.

[0080] Step S2: Moisturizing the tobacco leaves by spraying, sealing the leaves in plastic bags and performing moisture balance in an environment of 30° C. for 40 hours, so that the moisture content of the tobacco leaves reaches 45%.

[0081] The water used for moistening is tobacco stem water. The tobacco stem water is prepared by adding 100°C water to the tobacco stems produced during the preparation process at a mass ratio of 1:15, soaking for 10 hours, and filtering the water.

[0082] Step S3: stack the tobacco leaves with the leaf tips facing inward and the leaf bases facing outward. The length and width of the tobacco stack are 1.4 m and the height is 1.1 m. After stacking, the surface of the tobacco stack is covered with cotton cloth.

[0083] Step S4: placing the tobacco pile in a temperature- and humidity-controlled environment for fermentation at 30° C. and 75% relative humidity. When the core temperature of the pile exceeds 56° C., the pile is turned over to maintain the core temperature between 33° C. and 56° C. for fermentation for a total of 46 days. If the core temperature does not exceed 56° C., the pile is turned over once every 10 days.

[0084] Step S5: Perform a secondary vacuum treatment to even out the moisture content of the tobacco leaves. The method is the same as step S1, except that no water mist is sprayed to moisten the leaves.

[0085] Step S6: Place the tobacco leaves in a 0°C environment and let them stand for 20 days until the moisture content of the tobacco leaves reaches 19%.

[0086] After the above steps S1 to S6, this embodiment obtains a dark brown cigar wrapper with good color uniformity.

[0087] Example 6

[0088] This embodiment provides a dark brown cigar wrapper with good color uniformity, and the preparation method includes the following steps:

[0089] Step S1: Place tobacco leaves in a rehumidification chamber, adjust the chamber temperature to 65°C, and evacuate to -95kPa. Maintain the vacuum in the chamber at -95kPa for 10 minutes. When the vacuum in the chamber reaches a preset value, spray a fine mist of water into the chamber to increase the moisture content of the tobacco leaves by 3%. This achieves uniform moisture content in the tobacco leaves under a vacuum of -95kPa.

[0090] Step S2: Moisturizing the tobacco leaves by spraying, sealing the leaves in plastic bags, and conducting moisture balance in an environment of 30° C. for 40 hours, so that the moisture content of the tobacco leaves reaches 50%.

[0091] The water used for moistening is tobacco stem water. The tobacco stem water is prepared by adding 100°C water to the tobacco stems produced during the preparation process at a mass ratio of 1:15, soaking for 10 hours, and filtering the water.

[0092] Step S3: stack the tobacco leaves with the leaf tips facing inward and the leaf bases facing outward. The length and width of the tobacco stack are 1.4m and the height is 1.3m. After stacking, the surface of the tobacco stack is covered with cotton cloth.

[0093] Step S4: placing the tobacco pile in a temperature- and humidity-controlled environment for fermentation at 30° C. and 80% relative humidity. When the core temperature of the pile exceeds 56° C., the pile is turned over to maintain the core temperature between 33° C. and 56° C. for fermentation for a total of 46 days. If the core temperature does not exceed 56° C., the pile is turned over once every 10 days.

[0094] Step S5: Perform a secondary vacuum treatment to even out the moisture content in the tobacco leaves. The method is the same as step S1, except that the vacuum degree is -105 kPa and no water mist is sprayed for moistening.

[0095] Step S6: Place the tobacco leaves in a 5°C environment and let them stand for 15 days to reduce the moisture content of the tobacco leaves to 21%.

[0096] After the above steps S1 to S6, this embodiment obtains a dark brown cigar wrapper with good color uniformity.

[0097] Comparative Example 1

[0098] The main difference from Example 1 is that the vacuum treatment in step S1 is not performed. Other steps are the same as those in Example 1.

[0099] This comparative example provides a cigar wrapper, which is prepared according to the following method:

[0100] Step S1: Moisten the tobacco leaves using a spray moistening method. After sealing in a plastic bag, the leaves are allowed to equilibrate at 30°C for 40 hours, until their moisture content reaches 47%. The water used for moistening is tobacco stem water. The tobacco stem water is prepared by adding 100°C water to the tobacco stems produced during the preparation process at a mass ratio of 1:15, soaking for 10 hours, and filtering.

[0101] Step S2: stack the tobacco leaves with the leaf tips facing inward and the leaf bases facing outward. The length and width of the tobacco stack are 1.4 m and the height is 1.2 m. After stacking, the surface of the tobacco stack is covered with cotton cloth.

[0102] Step S3: placing the tobacco pile in a temperature- and humidity-controlled environment for fermentation at a temperature of 25° C. and a relative humidity of 78%. When the core temperature of the pile exceeds 56° C., the pile is turned over to maintain the core temperature at 33° C. to 56° C. for fermentation for a total of 46 days. If the core temperature does not exceed 56° C., the pile is turned over once every 10 days.

[0103] Step S4: vacuum treatment is performed to make the moisture content of the tobacco leaves uniform. The method is the same as step S1, except that the vacuum degree is -95 kPa and no water mist is sprayed to add moisture.

[0104] Step S5: Place the tobacco leaves in a rehumidification chamber, adjust the chamber temperature to 65°C, evacuate to -95 kPa, and maintain the vacuum degree at -95 kPa for 10 minutes. The tobacco leaves achieve uniform moisture content in a vacuum degree of -95 kPa.

[0105] Step S6: Place the tobacco leaves in a 0°C environment and let them stand for 17 days until the moisture content of the tobacco leaves reaches 23%.

[0106] Comparative Example 2

[0107] The main difference from Example 1 is that the vacuum treatment in step S5 is not performed. Other steps are the same as those in Example 1.

[0108] This comparative example provides a cigar wrapper, which is prepared according to the following method:

[0109] Step S1: Place tobacco leaves in a dehumidification chamber, adjust the chamber temperature to 65°C, and evacuate to -85kPa. Maintain the vacuum in the chamber at -85kPa for 10 minutes. When the vacuum in the chamber reaches a preset value, spray a fine mist of water into the chamber to increase the moisture content of the tobacco leaves by 3%. The tobacco leaves achieve uniform moisture content in the -85kPa vacuum.

[0110] Step S2: Moisturizing the tobacco leaves by spraying, sealing the leaves in plastic bags, and conducting moisture balance in an environment of 30° C. for 40 hours, so that the moisture content of the tobacco leaves reaches 47%.

[0111] The water used for moistening is tobacco stem water. The tobacco stem water is prepared by adding 100°C water to the tobacco stems produced during the preparation process at a mass ratio of 1:15, soaking for 10 hours, and filtering the water.

[0112] Step S3: stack the tobacco leaves with the leaf tips facing inward and the leaf bases facing outward. The length and width of the tobacco stack are 1.4 m and the height is 1.2 m. After stacking, the surface of the tobacco stack is covered with cotton cloth.

[0113] Step S4: placing the tobacco pile in a temperature- and humidity-controlled environment for fermentation at 25° C. and 78% relative humidity. When the core temperature of the pile exceeds 56° C., the pile is turned over to maintain the core temperature between 33° C. and 56° C. for fermentation for a total of 46 days. If the core temperature does not exceed 56° C., the pile is turned over once every 10 days.

[0114] Step S5: Place the tobacco leaves in a 0°C environment and let them stand for 17 days until the moisture content of the tobacco leaves reaches 23%.

[0115] Comparative Example 3

[0116] The main difference from Example 1 is that step S6 is carried out in the air at room temperature of 25° C. The other steps are the same as those in Example 1.

[0117] This comparative example provides a cigar wrapper, which is prepared according to the following method:

[0118] Step S1: Place tobacco leaves in a dehumidification chamber, adjust the chamber temperature to 65°C, and evacuate to -85kPa. Maintain the vacuum in the chamber at -85kPa for 10 minutes. When the vacuum in the chamber reaches a preset value, spray a fine mist of water into the chamber to increase the moisture content of the tobacco leaves by 3%. The tobacco leaves achieve uniform moisture content in the -85kPa vacuum.

[0119] Step S2: Moisturizing the tobacco leaves by spraying, sealing the leaves in plastic bags, and conducting moisture balance in an environment of 30° C. for 40 hours, so that the moisture content of the tobacco leaves reaches 47%.

[0120] The water used for moistening is tobacco stem water. The tobacco stem water is prepared by adding 100°C water to the tobacco stems produced during the preparation process at a mass ratio of 1:15, soaking for 10 hours, and filtering the water.

[0121] Step S3: stack the tobacco leaves with the leaf tips facing inward and the leaf bases facing outward. The length and width of the tobacco stack are 1.4 m and the height is 1.2 m. After stacking, the surface of the tobacco stack is covered with cotton cloth.

[0122] Step S4: placing the tobacco pile in a temperature- and humidity-controlled environment for fermentation at 25° C. and 78% relative humidity. When the core temperature of the pile exceeds 56° C., the pile is turned over to maintain the core temperature between 33° C. and 56° C. for fermentation for a total of 46 days. If the core temperature does not exceed 56° C., the pile is turned over once every 10 days.

[0123] Step S5: Perform a secondary vacuum treatment to make the moisture content of the tobacco leaves uniform. The method is the same as step S1, except that the vacuum degree is -95kPa and no water mist is sprayed for moistening.

[0124] Step S6: placing the tobacco leaves in an environment of 25° C. and leaving them to stand for 13 days until the moisture content of the tobacco leaves is 23%.

[0125] Comparative Example 4

[0126] The main difference from Example 1 is that in step S4, the temperature of the core is kept at 60-70° C. for fermentation. The other steps are the same as those in Example 1.

[0127] This comparative example provides a cigar wrapper, which is prepared according to the following method:

[0128] Step S1: Place tobacco leaves in a dehumidification chamber, adjust the chamber temperature to 65°C, and evacuate to -85kPa. Maintain the vacuum in the chamber at -85kPa for 10 minutes. When the vacuum in the chamber reaches a preset value, spray a fine mist of water into the chamber to increase the moisture content of the tobacco leaves by 3%. The tobacco leaves achieve uniform moisture content in the -85kPa vacuum.

[0129] Step S2: Moisturizing the tobacco leaves by spraying, sealing the leaves in plastic bags, and conducting moisture balance in an environment of 30° C. for 40 hours, so that the moisture content of the tobacco leaves reaches 47%.

[0130] The water used for moistening is tobacco stem water. The tobacco stem water is prepared by adding 100°C water to the tobacco stems produced during the preparation process at a mass ratio of 1:15, soaking for 10 hours, and filtering the water.

[0131] Step S3: stack the tobacco leaves with the leaf tips facing inward and the leaf bases facing outward. The length and width of the tobacco stack are 1.4 m and the height is 1.2 m. After stacking, the surface of the tobacco stack is covered with cotton cloth.

[0132] Step S4: The tobacco stack is placed in a temperature- and humidity-controlled environment for fermentation, during which the core temperature of the stack is monitored. The fermentation environment temperature is 25°C and the relative humidity is 78%. The stack is turned once every 10 days for a total of 46 days of fermentation. During this period, the core temperature of the stack was monitored to be between 60°C and 70°C for 32 days.

[0133] Step S5: Perform a secondary vacuum treatment to make the moisture content of the tobacco leaves uniform. The method is the same as step S1, except that the vacuum degree is -95kPa and no water mist is sprayed for moistening.

[0134] Step S6: Place the tobacco leaves in a 0°C environment and let them stand for 17 days until the moisture content of the tobacco leaves reaches 23%.

[0135] Performance Characterization

[0136] Take the cigar wrappers obtained in Examples 1 to 6 and Comparative Examples 1 to 4, and record the color of the cigar wrappers, as shown in Table 1. The comparison of the cigar wrappers obtained in Comparative Examples 1 to 4 and Example 1 is shown in the figure below. Figure 1 As shown, the wrappers from left to right are Example 1 and Comparative Examples 1-4.

[0137] Table 1

[0138]

[0139]

[0140] From this we can see that:

[0141] ① The wrapper prepared in the present invention demonstrates that the present invention, through a sequential process of primary vacuum treatment, tobacco leaf conditioning, stacking, fermentation, secondary vacuum treatment, and low-temperature drying, produces a dark brown cigar wrapper with uniform color. Specifically, the present invention vacuum treats the tobacco leaves before and after fermentation to achieve uniform color change.

[0142] ② A comparison between Comparative Example 1 and Example 1 shows that the tobacco leaves in Comparative Example 1, which were not vacuum-treated before fermentation, produced a mottled and uneven wrapper. This suggests that subjecting the tobacco leaves to a vacuum treatment for a certain period of time improves moisture uniformity and promotes uniform color change. This may be because vacuum treatment softens the tobacco leaves, which facilitates full fermentation and color change.

[0143] ③ From the comparative analysis of Comparative Example 2 and Example 1, it can be seen that the tobacco leaves in Comparative Example 2 are not vacuum treated after fermentation, and the resulting wrapper is mottled and uneven in color, and the color of Comparative Example 2 is darker than that of Comparative Example 1. This shows that placing the tobacco leaves in a vacuum environment for a certain period of time after fermentation is beneficial to the color balance of the tobacco leaves and improves the color uniformity of the tobacco leaf surface.

[0144] ④ From the comparative analysis of Comparative Example 3 and Example 1, it can be seen that the present invention plays an important role in drying at low temperature.

[0145] ⑤ Comparison of Comparative Example 4 with Example 1 reveals that in Comparative Example 4, fermentation temperature was maintained between 60°C and 70°C, resulting in a mottled and uneven wrapper. This demonstrates that excessively high fermentation temperatures can lead to significant uneven tobacco color. Analysis of the tobacco leaves fermented at a core temperature above 56°C revealed significant mildew, resulting in a mottled wrapper surface.

[0146] Unless otherwise specified, the raw materials and equipment used in the present invention are commonly used in the art; the methods used in the present invention are conventional methods in the art unless otherwise specified.

[0147] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent transformation made to the above embodiment based on the technical essence of the present invention still fall within the scope of protection of the technical solution of the present invention.

Claims

1. A method for making a dark brown cigar wrapper, characterized by: Using the sun-grown cigar wrapper tobacco leaves from the upper second shed as raw materials, the following operations are performed: Step S1: Perform a vacuum treatment with a vacuum degree of not less than -85 kPa and a temperature of 60-70°C, and let it stand for 10-15 minutes to make the moisture content of the tobacco leaves uniform and increase the moisture content of the tobacco leaves by 2-4%; Step S2: rehumidify the tobacco leaves to a moisture content of 45-50%; Step S3, stacking the tobacco leaves to obtain a stack with a height of 1.1 to 1.3 m; Step S4, performing fermentation treatment, during which the temperature of the core is kept at 33-56° C., the fermentation treatment environment is in a high humidity state, the relative humidity of the high humidity state environment is 75-80%, and the ambient temperature is 25-30° C.; Step S5: perform a secondary vacuum treatment with a vacuum degree of not less than -98 kPa and a temperature of 60-70°C, and let it stand for 10-15 minutes to make the moisture content of the tobacco leaves uniform; Step S6: Place the tobacco leaves in a low temperature environment of 0-5°C for no more than 20 days to reduce the moisture content of the tobacco leaves to below 25%.

2. The method for making a dark brown cigar wrapper according to claim 1, wherein: In step S4, the temperature of the core is kept at 40-50° C. during fermentation.

3. The method for making a dark brown cigar wrapper according to claim 1, wherein: In step S2, the water used for moistening the tobacco leaves is tobacco stem water, and the preparation method of the tobacco stem water is: take the tobacco stems produced in the preparation process, add 90-100°C water at a mass ratio of 1:10-15, soak for 10-16 hours, and filter to obtain the water.

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