A processing method for improving the color depth of cigar wrapper

Abstract

The present invention relates to the technical field of cigar processing, and discloses a treatment method for enhancing the color depth of cigar wrappers. The method employs an aqueous solution of amino acids and sugars for humidification, subjecting tobacco leaves to a high temperature environment of 35-45°C for infiltration of an externally applied Maillard reaction substrate and accumulation of the Maillard reaction substrate. The tobacco leaves are then fumigated in high-temperature steam at 55-70°C to promote rapid and extensive reaction of the Maillard reaction substrate on the leaves. Finally, a mild environment of 23-27°C is maintained to stabilize the converted substances, promoting the production of dark, uniform cigar leaves. The resulting dark, uniform cigar leaves exhibit good gloss and sufficient oil content.

Description

Technical Field

[0001] The present invention relates to the technical field of cigar processing, and in particular to a processing method for improving the color depth of a cigar wrapper. Background Art

[0002] A complete cigar consists of three parts: the filler, the binder, and the wrapper. The wrapper, the outermost layer of the cigar, determines its appearance. As the visual centerpiece of a cigar, the color of the wrapper directly impacts its visual appeal. The main reasons for this are: first, darker wrappers are typically more mature, offering greater resilience and protection; second, darker wrappers indicate a richer flavor, allowing consumers to discern a cigar's flavor based on their color; and third, darker wrappers signal a mature tobacco leaf, reflecting a higher level of fermentation and maturity. Furthermore, dark wrappers are complex and expensive to produce, and therefore reflect higher quality and craftsmanship.

[0003] Melanin in tobacco leaves is closely related to their color; the higher the melanin content, the darker the color. Existing techniques often promote melanin production by adjusting the temperature and humidity during the fermentation process. However, the maximum color depth achievable depends heavily on the quality of the cigar tobacco raw material, and the achievable color depth is relatively shallow. Summary of the Invention

[0004] To address the above technical issues, the present invention provides a treatment method for enhancing the color depth of cigar wrappers. The method utilizes an aqueous solution of amino acids and sugars for humidification. The tobacco leaves are exposed to a high-temperature environment of 35-45°C to complete the infiltration of the externally applied Maillard reaction substrate and the accumulation of the Maillard reaction substrate. The tobacco leaves are then fumigated in high-temperature steam at 55-70°C to promote a rapid and extensive reaction of the Maillard reaction substrate on the leaves. Finally, the tobacco leaves are maintained in a milder environment of 23-27°C to maintain the stability of the converted substances, thereby achieving dark, uniform cigar tobacco leaves.

[0005] The specific technical solutions of the present invention are:

[0006] In one aspect, the present invention provides a method for enhancing the color depth of a wrapper, comprising the following steps:

[0007] Step S1: adding a mixed aqueous solution of amino acids and sugars to the cigar tobacco leaves to be treated, so that the moisture content of the tobacco leaves is 30-35%;

[0008] Step S2: placing the tobacco leaves in a high temperature environment of 35-45°C for 15-20 days;

[0009] Step S3: fumigating the tobacco leaves with high-temperature steam at 55-70° C. for 40-60 minutes;

[0010] Step S4: placing the tobacco leaves in a mild environment of 23-27°C for 3-7 days.

[0011] Melanin in tobacco leaves is closely related to the color of tobacco leaves. The more melanin content, the darker the color of the tobacco leaves. Melanin in tobacco leaves is divided into two major categories: one is polyphenol conversion products, including oxides of colorless polyphenols such as rutin and chlorogenic acid, and anthocyanins, flavonoids, catechins, etc. with a certain color. Under the action of polyphenol oxidase, they are often polymerized into dark brown substances, also known as enzymatic browning pigments; the other is sugar and ammonia nitrogen compounds that form melanoidins through molecular rearrangement, which are called non-enzymatic browning pigments, also known as Maillard reaction products. The present invention regulates the conversion of polyphenol substances and promotes the synthesis of Maillard reaction products to deepen the color of tobacco leaves through the above-mentioned steps S1 to S4. The cigar tobacco leaves obtained by the method of the present invention are dark and uniform in color, have good gloss, and are sufficient in oil. The functions of steps S1 to S4 of the present invention are as follows:

[0012] First, step S1 uses an aqueous solution of amino acids and sugars for moistening. One of the functions of amino acids and sugars is to participate in the production of melanin as reaction substrates; second, they provide a carbon source for the growth of microorganisms on the surface of the tobacco leaves, which is beneficial to the transformation of substances in the tobacco leaves, so as to form more Maillard reactions of their own products and promote the production of melanin in the tobacco leaves; third, the flavor of sugars and amino acids themselves affects the quality of the tobacco leaves. In step S1, the tobacco leaves are moistened to a moisture content of 30-35%. The purpose is to increase the water activity in the tobacco leaves accordingly, providing the necessary medium conditions for substance transformation and reaction. In a high moisture state, the solubility of enzymes, reaction substrates, etc. in the tobacco leaves is better, increasing the contact opportunities between substances, thereby promoting the Maillard reaction. However, the moisture content should not be too high, and the moisture content cannot exceed 35%. This is because when the moisture content exceeds 35%, the amino acids and sugars attached to the tobacco leaves decrease, resulting in less melanin accumulated in the tobacco leaves after the reaction, and the tobacco leaves are lighter in color. In step S2, the tobacco leaves are placed in a high temperature environment of 35-45°C for 15-20 days. By setting the temperature, the activity of polyphenol oxidase is increased, promoting the degradation of polyphenols into melanin. At the same time, in this step, the substance conversion in the tobacco leaves is completed, so that the Maillard reaction substrates derived from the tobacco leaves themselves are accumulated, making full preparations for the next Maillard reaction. The temperature and humidity suitable for the Maillard reaction are usually between 30°C and 120°C. When the temperature is below 30°C, the speed of the Maillard reaction is relatively slow. Increasing the temperature can accelerate the speed of the Maillard reaction, but too high a temperature will have a negative impact and produce undesirable products. In step S3, the tobacco leaves are fumigated in high-temperature steam at 55-70°C to promote the Maillard reaction. The amino acids and sugars added in step S1, after the conditions for enzyme activation and substance accumulation in step S2, can undergo a rapid and large-scale Maillard reaction in this step, so that a large amount of melanin accumulates in the tobacco leaves, obtaining dark black tobacco leaves. The use of high-temperature steam can increase the contact between substances, thereby promoting the Maillard reaction and allowing the reaction to occur quickly and evenly. In step S4, the tobacco leaves are placed in a relatively mild temperature environment to slowly extinguish the Maillard reaction, maintain the stability of moisture and tobacco leaf state, promote the stability of the converted tobacco leaf substances, and thus maintain the stability of the dark black color.

[0013] As a preferred embodiment of the above treatment method, in step S1, the amino acid is a mixture of lysine, phenylalanine and glutamic acid, wherein the mixing mass ratio is 10:(1-7):(5-10).

[0014] In step S1, in order to deepen the color of the tobacco leaves, the present invention adds a mixture of lysine, phenylalanine and glutamic acid in a mass ratio of 10:(1-7):(5-10) to the tobacco leaves. When the added lysine residue undergoes a Maillard reaction, a darker color can be produced. Glutamic acid and phenylalanine produce aromas such as sweet and floral aromas in the Maillard reaction, thereby increasing the richness of the tobacco leaf aroma. When the mass ratio of lysine, phenylalanine and glutamic acid is 10:(1-7):(5-10), the tobacco leaf aroma quality can be optimized while ensuring the darkest color.

[0015] As a preferred embodiment of the above treatment method, the amount of amino acid added is 2-5% of the weight of the tobacco leaves.

[0016] As a preferred embodiment of the above treatment method, in step S1, the sugar is ribose and / or xylose.

[0017] The sugars used are ribose and xylose, both of which are pentose. Under the fumigation conditions of the present invention, the Maillard reaction rate of the above two sugars is greater than that of other sugars.

[0018] As a preferred embodiment of the above treatment method, the amount of sugar added is 2-5% of the weight of the tobacco leaves.

[0019] As a preferred embodiment of the above treatment method, in step S2, the relative humidity of the environment is 70-75%.

[0020] A high humidity environment of 70~75%RH is conducive to the progress of enzymatic reactions and the accumulation of Maillard reaction substrates in the tobacco leaves themselves, making full preparations for the next Maillard reaction.

[0021] As a preferred embodiment of the above treatment method, in step S4, the relative humidity of the environment is 74-78%.

[0022] Step S4 is a step for quenching the Maillard reaction. In a high humidity environment of 74-78% RH, the infiltration of the converted tobacco material can be promoted, which is beneficial to the uniformity of the tobacco color and maintains the stability of the moisture and tobacco state, so that the deep black color of the tobacco remains stable.

[0023] As a preferred embodiment of the above treatment method, after step S4, the tobacco leaves are subjected to a drying step, wherein the drying step is performed at a temperature of 16-18° C. and a relative humidity of 65-70%.

[0024] Cigars are used at a relatively low moisture content. Cigar raw materials are generally dried to a relatively low moisture content before use. Following the treatment process of the present invention, the tobacco leaves need to be dried in an environment with relatively low temperature and relatively high humidity, specifically at a temperature of 16-18°C and a relative humidity of 65-70%. This prevents the leaves from lightening in color during the drying process and effectively avoids oil loss due to excessive drying.

[0025] More preferably, the drying step adjusts the moisture content of the tobacco leaves to 18-22%.

[0026] In another aspect, the present invention provides cigar tobacco leaves obtained by the above-mentioned treatment method.

[0027] Compared with the prior art, the present invention has the following technical effects:

[0028] (1) The present invention uses an aqueous solution of amino acids and sugars for moistening, and allows tobacco leaves to complete the infiltration of the external Maillard reaction substrate and the accumulation of the Maillard reaction substrate in a high temperature environment of 35-45°C. Then, the tobacco leaves are fumigated in high temperature steam at 55-70°C to promote the rapid and large-scale reaction of the Maillard reaction substrate on the tobacco leaves. Finally, the stability of the transformed substances is maintained in a mild environment of 23-27°C, promoting the acquisition of dark and uniform cigar tobacco leaves, and ultimately obtaining dark and uniform cigar tobacco leaves. The processed cigar tobacco leaves have good gloss and sufficient oil content. Specifically: First, step S1 uses an aqueous solution of amino acids and sugars for moistening. One of the functions of amino acids and sugars is to participate in the production of melanin as reaction substrates; second, it provides a carbon source for the growth of microorganisms on the surface of tobacco leaves, which is beneficial to the transformation of substances in the tobacco leaves, so as to form more Maillard reactions of their own products and promote the production of melanin in the tobacco leaves; third, the flavor of sugars and amino acids themselves affects the quality of tobacco leaves. In step S1, the tobacco leaves are moistened until the moisture content is 30-35%. The purpose is to increase the water activity in the tobacco leaves accordingly, provide necessary medium conditions for material conversion and reaction, and under high moisture conditions, the solubility of enzymes, reaction substrates, etc. in the tobacco leaves is better, increasing the contact opportunity between substances, thereby promoting the Maillard reaction. However, the moisture should not be too much, and the moisture content should not exceed 35%. This is because when the moisture content exceeds 35%, the amino acids and sugars attached to the tobacco leaves decrease, and after the reaction, the melanin accumulated in the tobacco leaves decreases, and the tobacco leaves are lighter in color. In step S2, the tobacco leaves are placed in a high temperature environment of 35-45°C for 15-20 days. By setting the temperature, the polyphenol oxidase activity is increased, and the degradation of polyphenols is promoted to be converted into melanin. At the same time, in this step, the material conversion in the tobacco leaves is completed, so that the Maillard reaction substrates derived from the tobacco leaves themselves are accumulated, and full preparations are made for the next Maillard reaction. The temperature and humidity suitable for the Maillard reaction are usually between 30°C and 120°C. When the temperature is below 30°C, the speed of the Maillard reaction is slow. Increasing the temperature can accelerate the Maillard reaction speed, but too high a temperature will have a negative impact and produce undesirable products. In step S3, the tobacco leaves are fumigated in high-temperature steam at 55-70°C to promote the progress of the Maillard reaction. The amino acids and sugars added in step S1, after the conditions for enzyme activation and substance accumulation in step S2, can undergo a rapid and large-scale Maillard reaction in this step, so that a large amount of melanin accumulates in the tobacco leaves, obtaining dark black tobacco leaves. The use of high-temperature steam can increase the contact between substances, thereby promoting the progress of the Maillard reaction, and the reaction can occur quickly and evenly. In step S4, the tobacco leaves are placed in a relatively mild temperature environment to slowly extinguish the Maillard reaction, keep the moisture and tobacco leaves stable, promote the stability of the tobacco leaf substances after conversion, and thus maintain the stability of the dark black color.

[0029] (2) The method of the present invention promotes the darkening of the wrapper color by regulating the transformation and production of tobacco leaf substances, which can enhance the original aroma of tobacco and ensure that the sensory quality meets production requirements. At the same time, the method is simple to operate, the medium used is low in cost, and it is easy to produce and convert. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 These are the appearance pictures of the citrus wrappers obtained by processing in Application Examples 1 to 3 and Comparative Examples 1 to 4 of the present invention. DETAILED DESCRIPTION

[0031] 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.

[0032] Melanin in tobacco leaves is closely related to their color: the higher the melanin content, the darker the leaf color. Melanin in tobacco leaves is divided into two major categories: one is polyphenol conversion products, including oxides of colorless polyphenols such as rutin and chlorogenic acid, and colored anthocyanins, flavonoids, and catechins. Under the action of polyphenol oxidase, they often polymerize into dark brown substances, also known as enzymatic browning pigments; the other is sugar and ammonia nitrogen compounds that form melanoidins through molecular rearrangement. These are called non-enzymatic browning pigments and are also called Maillard reaction products. The present invention uses an aqueous solution of amino acids and sugars for humidification, and allows tobacco leaves to complete the infiltration of external Maillard reaction substrates and the accumulation of their own Maillard reaction substrates in a high-temperature environment of 35-45°C. The tobacco leaves are then fumigated in high-temperature steam at 55-70°C to promote a rapid and large-scale reaction of the Maillard reaction substrates on the tobacco leaves. Finally, a mild environment of 23-27°C is used to maintain the stability of the converted substances, thereby promoting the acquisition of dark and uniform cigar tobacco leaves. Thus, through the above multiple steps, the conversion of polyphenols is regulated and the synthesis of Maillard reaction products is promoted, thereby promoting the deepening of the color of the tobacco leaves.

[0033] Example 1

[0034] This embodiment provides a method for enhancing the color depth of the wrapper, comprising the following steps:

[0035] Step S1: adding a mixed aqueous solution of amino acids and sugars to the cigar tobacco leaves to be treated, so that the moisture content of the tobacco leaves is 30-35%;

[0036] Step S2: placing the tobacco leaves in a high temperature environment of 35-45°C for 15-20 days;

[0037] Step S3: fumigating the tobacco leaves with high-temperature steam at 55-70° C. for 40-60 minutes;

[0038] Step S4: placing the tobacco leaves in a mild environment of 23-27°C for 3-7 days.

[0039] The functions of the above steps S1 to S4 are as follows:

[0040] First, step S1 uses an aqueous solution of amino acids and sugars for moistening. One of the functions of amino acids and sugars is to participate in the production of melanin as reaction substrates; second, they provide a carbon source for the growth of microorganisms on the surface of the tobacco leaves, which is beneficial to the transformation of substances in the tobacco leaves, so as to form more Maillard reactions of their own products and promote the production of melanin in the tobacco leaves; third, the flavor of sugars and amino acids themselves affects the quality of the tobacco leaves. In step S1, the tobacco leaves are moistened to a moisture content of 30-35%. The purpose is to increase the water activity in the tobacco leaves accordingly, providing the necessary medium conditions for substance transformation and reaction. In a high moisture state, the solubility of enzymes, reaction substrates, etc. in the tobacco leaves is better, increasing the contact opportunities between substances, thereby promoting the Maillard reaction. However, the moisture content should not be too high, and the moisture content cannot exceed 35%. This is because when the moisture content exceeds 35%, the amino acids and sugars attached to the tobacco leaves decrease, resulting in less melanin accumulated in the tobacco leaves after the reaction, and the tobacco leaves are lighter in color. In step S2, the tobacco leaves are placed in a high temperature environment of 35-45°C for 15-20 days. By setting the temperature, the activity of polyphenol oxidase is increased, promoting the degradation of polyphenols into melanin. At the same time, in this step, the substance conversion in the tobacco leaves is completed, so that the Maillard reaction substrates derived from the tobacco leaves themselves are accumulated, making full preparations for the next Maillard reaction. The temperature and humidity suitable for the Maillard reaction are usually between 30°C and 120°C. When the temperature is below 30°C, the speed of the Maillard reaction is relatively slow. Increasing the temperature can accelerate the speed of the Maillard reaction, but too high a temperature will have a negative impact and produce undesirable products. In step S3, the tobacco leaves are fumigated in high-temperature steam at 55-70°C to promote the Maillard reaction. The amino acids and sugars added in step S1, after the conditions for enzyme activation and substance accumulation in step S2, can undergo a rapid and large-scale Maillard reaction in this step, so that a large amount of melanin accumulates in the tobacco leaves, obtaining dark black tobacco leaves. The use of high-temperature steam can increase the contact between substances, thereby promoting the Maillard reaction and allowing the reaction to occur quickly and evenly. In step S4, the tobacco leaves are placed in a relatively mild temperature environment to slowly extinguish the Maillard reaction, maintain the stability of moisture and tobacco leaf state, promote the stability of the converted tobacco leaf substances, and thus maintain the stability of the dark black color.

[0041] As a preference of this embodiment, in step S1, the amino acid is a mixture of lysine, phenylalanine and glutamic acid, wherein the mixing mass ratio is 10:(1-7):(5-10).

[0042] In step S1, in order to deepen the color of the tobacco leaves, in this embodiment, a mixture of lysine, phenylalanine, and glutamic acid in a mass ratio of 10:(1-7):(5-10) is added to the tobacco leaves. When the lysine residues undergo a Maillard reaction, a darker color can be produced. Glutamic acid and phenylalanine produce sweet, floral, and other aromas in the Maillard reaction, thereby increasing the aroma richness of the tobacco leaves. When the mass ratio of lysine, phenylalanine, and glutamic acid is 10:(1-7):(5-10), the tobacco leaves have the best aroma quality and the darkest color can be ensured.

[0043] As a preference of this embodiment, the amount of amino acids added is 2-5% of the weight of the tobacco leaves.

[0044] As a preference of this embodiment, in step S1, the sugar is ribose and / or xylose.

[0045] The sugars used are ribose and xylose, both of which are pentose. Under the fumigation conditions of the present invention, the Maillard reaction rate of the above two sugars is greater than that of other sugars.

[0046] As a preference of this embodiment, the added amount of the sugar is 2-5% of the weight of the tobacco leaves.

[0047] As a preference of this embodiment, in step S2, the relative humidity of the environment is 70-75%.

[0048] A high humidity environment of 70~75%RH is conducive to the progress of enzymatic reactions and the accumulation of Maillard reaction substrates in the tobacco leaves themselves, making full preparations for the next Maillard reaction.

[0049] As a preference of this embodiment, in step S4, the relative humidity of the environment is 74-78%.

[0050] Step S4 is a step for quenching the Maillard reaction. In a high humidity environment of 74-78% RH, the infiltration of the converted tobacco material can be promoted, which is beneficial to the uniformity of the tobacco color and maintains the stability of the moisture and tobacco state, so that the deep black color of the tobacco remains stable.

[0051] As a preference of this embodiment, after step S4, the tobacco leaves are subjected to a drying step, wherein the drying step is performed at a temperature of 16-18° C. and a relative humidity of 65-70%.

[0052] Cigars are used at a relatively low moisture content. Cigar raw materials are generally dried to a relatively low moisture content before use. Following the treatment process of this embodiment, the tobacco leaves need to be dried in an environment with relatively low temperature and relatively high humidity, specifically at a temperature of 16-18°C and a relative humidity of 65-70%. This prevents the leaves from lightening in color during the drying process and effectively avoids oil loss due to excessive drying.

[0053] More preferably, the drying step adjusts the moisture content of the tobacco leaves to 18-22%.

[0054] Compared with the prior art, the present invention has the following technical effects:

[0055] (1) In this embodiment, an aqueous solution of amino acids and sugars is used for humidification, and the tobacco leaves are subjected to a high temperature environment of 35-45°C to complete the infiltration of the external Maillard reaction substrate and the accumulation of the Maillard reaction substrate themselves. The tobacco leaves are then fumigated in high temperature steam at 55-70°C to promote the rapid and large-scale reaction of the Maillard reaction substrate on the tobacco leaves. Finally, the stability of the converted substances is maintained in a mild environment of 23-27°C, thereby promoting the acquisition of dark and uniform cigar tobacco leaves. Finally, dark and uniform cigar tobacco leaves are obtained, and the treated cigar tobacco leaves have good gloss and sufficient oil content.

[0056] (2) The method of the present invention promotes the darkening of the wrapper color by regulating the transformation and production of tobacco leaf substances, which can enhance the original aroma of tobacco and ensure that the sensory quality meets production requirements. At the same time, the method is simple to operate, the medium used is low in cost, and it is easy to produce and convert.

[0057] Application Example 1

[0058] Based on the method provided in Example 1, this application example provides a dark cigar wrapper, which has an appearance as follows: Figure 1 shown.

[0059] The tobacco leaves in this application example are processed according to the following steps:

[0060] (1) Adding a mixed aqueous solution of amino acids and xylose to cigar tobacco leaves to be treated so that the moisture content of the tobacco leaves is 32%; wherein the amino acids are a mixture of lysine, phenylalanine and glutamic acid, wherein the mixing mass ratio is 10:4:7; the amount of the amino acids added is 4% of the weight of the tobacco leaves; and the amount of the sugar added is 4% of the weight of the tobacco leaves.

[0061] (2) Place the tobacco leaves in a high temperature environment with a temperature of 35-45°C and a relative humidity of 70-75% for 18 days;

[0062] (3) Use high-temperature steam at 60-65°C to fumigate tobacco leaves for 50 minutes;

[0063] (4) Place the tobacco leaves in an environment with a temperature of 23-27°C and a relative humidity of 74-78% for 5 days.

[0064] (5) Place the tobacco leaves in an environment with a temperature of 16-18°C and a relative humidity of 65-70% for drying, so that the moisture content of the tobacco leaves is reduced to 20%.

[0065] Depend on Figure 1 From the appearance of the cigars shown in Application Example 1, it can be seen that the cigar tobacco leaves processed by the method of this embodiment have a dark and uniform color, good gloss, and sufficient oil content.

[0066] Application Example 2

[0067] Based on the method provided in Example 1, this application example provides a dark cigar wrapper, which has an appearance as follows: Figure 1 shown.

[0068] The main difference between this application example and application example 1 is that in step (3), high-temperature steam at 55-60°C is used to fumigate the tobacco leaves. Other steps are the same as those in application example 1.

[0069] Depend on Figure 1 From the comparison of the appearance of the cigar wrappers shown in Application Example 1 and Application Example 2, it can be seen that the cigar wrapper obtained by fumigating the tobacco leaves with high-temperature steam at 60~65℃ is darker in color.

[0070] Application Example 3

[0071] Based on the method provided in Example 1, this application example provides a dark cigar wrapper, which has an appearance as follows: Figure 1 shown.

[0072] The main difference between this application example and application example 1 is that in step (3), high-temperature steam at 65-70°C is used to fumigate tobacco leaves. Other steps are the same as those in application example 1.

[0073] Depend on Figure 1 From the comparison of the appearance of the cigar wrappers shown in Application Example 1 and Application Example 3, it can be seen that the cigar wrapper obtained by fumigating tobacco leaves with high-temperature steam at 60~65℃ is darker in color.

[0074] Comparative Example 1

[0075] Based on the method provided in Example 1, this comparative example provides a dark cigar wrapper, which has an appearance as follows: Figure 1 shown.

[0076] The main difference between this application example and application example 1 is that step (3) is not performed. The other steps are the same as those in application example 1.

[0077] Depend on Figure 1Comparison of the appearance of the tobacco wrappers shown in Application Example 1 and Comparative Example 1 shows that Application Example 1 was subjected to high-temperature steam fumigation at 60-65°C. The tobacco wrapper obtained in Application Example 1 was darker in color, dark black, and showed a higher oil content. Comparative Example 1 did not undergo high-temperature steam fumigation in step (3), and the tobacco wrapper obtained in Comparative Example 1 was lighter in color. The reason for this is that fumigating tobacco leaves in high-temperature steam at 60-65°C can promote the Maillard reaction. The amino acids and sugars added in step (1), after the enzyme activation and substance accumulation conditions in step (2), can undergo a rapid and large-scale Maillard reaction in the high-temperature steam fumigation, causing a large amount of melanin to accumulate in the tobacco leaves, resulting in dark black tobacco leaves. Comparative Example 1 did not undergo the high-temperature steam fumigation step, so the tobacco leaves in Comparative Example 1 were lighter in color.

[0078] Comparative Example 2

[0079] Based on the method provided in Example 1, this comparative example provides a dark cigar wrapper, which has an appearance as follows: Figure 1 shown.

[0080] The main difference between this application example and application example 1 is that step (3) is to place the tobacco leaves in an environment with a temperature of 60-65°C and a relative humidity of 75-80% for 50 minutes. The other steps are the same as those in application example 1.

[0081] Depend on Figure 1 A comparison of the wrappers shown in Application Example 1 and Comparative Example 1 shows that Application Example 1, which was subjected to high-temperature steam fumigation at 60-65°C for 50 minutes, produced a darker, deep black wrapper, demonstrating a higher oil content. Comparative Example 2, which subjected the tobacco leaves to a high-temperature, high-humidity environment at 60-65°C and a relative humidity of 75-80% for 50 minutes, produced a lighter wrapper with mottled and uneven color. The reason for this is that high-temperature steam increases contact between substances, promoting the Maillard reaction and allowing it to occur quickly and evenly. Consequently, Application Example 1 produced a dark and uniform cigar wrapper. Comparative Example 2, which subjected the tobacco leaves to a high-temperature, high-humidity environment, produced a darker, darker color, while Comparative Example 2, which subjected the tobacco leaves to a high-temperature, high-humidity environment. Although some Maillard reaction occurred and the color deepened, the color was still not as dark as that of Application Example 1 and exhibited uneven color.

[0082] Comparative Example 3

[0083] Based on the method provided in Example 1, this comparative example provides a dark cigar wrapper, which has an appearance as follows: Figure 1 shown.

[0084] The main difference between this application example and application example 1 is that step (4) is not performed. The other steps are the same as those in application example 1.

[0085] Depend on Figure 1 A comparison of the wrappers shown in Application Example 1 and Comparative Example 3 shows that the wrapper obtained in Application Example 1 is darker in color, while the wrapper obtained in Comparative Example 3 is lighter in color. This is due to the fact that immediately after the Maillard reaction, the moisture content and state of the tobacco leaves are not yet stable, and the converted tobacco substances are unstable. Direct drying of the tobacco leaves at this stage would result in the partial loss of the converted Maillard reaction products, resulting in a lighter tobacco color. Therefore, after fumigation, the tobacco leaves are placed in a relatively mild environment to slowly extinguish the Maillard reaction. This process stabilizes the substances in the cigar leaves and maintains their deep black color.

[0086] Comparative Example 4

[0087] Based on the method provided in Example 1, this comparative example provides a dark cigar wrapper, which has an appearance as follows: Figure 1 shown.

[0088] The main difference between this application example and application example 1 is that the ambient temperature in step (4) is 30-34°C. The other steps are the same as those in application example 1.

[0089] Depend on Figure 1 A comparison of the wrappers shown in Application Example 1 and Comparative Example 4 shows that the wrapper obtained in Application Example 1 is darker in color, while the wrapper obtained in Comparative Example 4 is lighter in color. This suggests that stabilizing tobacco leaves in a relatively mild temperature environment, slowly quenching the Maillard reaction and maintaining stable moisture and tobacco conditions, can promote the stability of post-conversion tobacco leaf materials and, in turn, maintain a deep black color, playing a crucial role in producing deep black cigar tobacco.

[0090] 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.

[0091] 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 increasing the color depth of a wrapper, characterized by: The following steps are involved: Step S1: adding a mixed aqueous solution of amino acids and sugars to the cigar tobacco leaves to be treated, so that the moisture content of the tobacco leaves is 30-35%; Step S2: placing the tobacco leaves in a high temperature environment of 35-45°C for 15-20 days; Step S3: fumigating the tobacco leaves with high-temperature steam at 55-70° C. for 40-60 minutes; Step S4: placing the tobacco leaves in a mild environment at 23-27°C for 3-7 days; in: In step S2, the relative humidity of the environment is 70-75%; In step S4, the relative humidity of the environment is 74-78%; After step S4, the tobacco leaves are dried at a temperature of 16-18° C. and a relative humidity of 65-70%.

2. The method for enhancing the color depth of a wrapper according to claim 1, characterized in that: In step S1, the amino acids are a mixture of lysine, phenylalanine and glutamic acid, wherein the mixing mass ratio is 10:(1-7):(5-10).

3. The method for enhancing the color depth of the wrapper according to claim 2, characterized in that: The added amount of the amino acid is 2-5% of the weight of the tobacco leaves.

4. The method for enhancing the color depth of a wrapper according to claim 1, characterized in that: In step S1, the sugar is ribose and / or xylose.

5. The method for enhancing the color depth of the wrapper according to claim 4, characterized in that: The added amount of the sugar is 2-5% of the weight of the tobacco leaves.

6. The method for enhancing the color depth of a wrapper according to claim 1, characterized in that: The drying step adjusts the moisture content of the tobacco leaves to 18-22%.

7. Cigar tobacco leaves obtained by the processing method according to any one of claims 1 to 6.

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