Fermentation method of cigar coating tobacco leaves and cigar tobacco leaves

Abstract

The invention discloses a fermentation method of cigar coating tobacco leaves and cigar tobacco leaves. A fermentation method for cigar coating tobacco leaves of cigars comprises the following steps that primary fermentation is conducted on raw cigar coating tobacco, specifically, the raw cigar coating tobacco leaves are boxed according to parts after being taken off a rod, primary fermentation is conducted, the fermentation temperature of lower leaves is 35-37 DEG C, the fermentation temperature of middle leaves is 36-38 DEG C, the fermentation temperature of upper leaves is 38-40 DEG C, the fermentation time is not shorter than 15 days, and after primary fermentation is completed, a tobacco box is cooled; secondary fermentation of the cigar-coated tobacco leaves: sorting out the cigar-coated tobacco leaves, bundling, humidifying and regaining moisture to enable the moisture content of the tobacco leaves to be 24%-26%, balancing the moisture, boxing and placing the tobacco leaves, carrying out secondary fermentation at the fermentation temperature of 38-40 DEG C for 30-50 days, and cooling the tobacco box after the secondary fermentation is completed; and alcoholizing and maintaining. The cigar coating output rate and the homogenization degree of the cigar tobacco leaves can be improved.

Description

Technical Field

[0001] This application relates to the technical field of tobacco fermentation, and particularly relates to a fermentation method for cigar wrapper tobacco leaves and cigar tobacco leaves. Background Art

[0002] Cigar is a tobacco product made by rolling after tobacco leaf modulation and fermentation. When smoked, it has characteristics such as a large smoke concentration and a strong aroma compared with flue-cured tobacco. Fermentation, as a key step in the production and processing of cigar tobacco leaves, can significantly improve the appearance characteristics and internal quality of tobacco leaves. Cigar tobacco leaf fermentation is a key link in the formation and manifestation of unique style characteristics and the last key technology for producing high-quality cigar tobacco leaves. It has the characteristics of high technical requirements, many process flows, a large amount of labor, and a long time cycle, and is mainly divided into natural fermentation and artificial fermentation. Fermentation is a whole process and method of accelerating the aging process, shortening the aging time, improving the smoking quality and processing performance under artificial intervention to meet the needs of factory processing. The original cigar tobacco leaves after air-curing have a low equilibrium moisture content and are easy to break. Overall, they show poor color uniformity, insufficient oil content, weak gloss, and a rigid leaf tissue structure. After fermentation, the equilibrium moisture content of tobacco leaves can be increased, the mildew rate can be reduced, the breakage rate during operations such as grading, packing, and transportation can be reduced, and the color uniformity, oil content, and grade structure can be improved. The main fermentation methods for cigar tobacco leaves include stacking fermentation method, packing fermentation method, pressure fermentation method, steam fermentation method, and medium fermentation method, etc. Selecting the correct fermentation method is the key to the successful fermentation of cigar tobacco leaves.

[0003] The fermentation methods adopted for Cuban cigar tobacco leaves are the stacking fermentation method and the packing fermentation method. The fermentation is carried out separately for shade-grown and sun-grown tobacco leaves. For shade-grown tobacco leaves, the packing fermentation method is mostly used, and the stacking fermentation method is also used in some cases; while for sun-grown tobacco leaves, the stacking fermentation method is used, and the threshold values of process parameters such as moisture, temperature, stack specifications, and fermentation time are mainly determined according to the harvesting batches. The fermentation of wrapper tobacco leaves belongs to small-volume, low-intensity, and short-time fermentation, which is beneficial to improving the color uniformity of tobacco leaves and increasing the yield of wrapper leaves, and avoiding problems such as local oil pressing and a large color difference between the leaf margin and the middle part of the leaf caused by stacking fermentation. The fermentation of binder tobacco leaves belongs to large-volume, high-intensity, multi-step, and long-cycle fermentation. The main determination indexes of the fermentation degree are color and smell, and the empirical nature is relatively strong. For Dominican wrapper and binder tobacco leaves, the stacking fermentation method is basically adopted. During the fermentation process, the fermentation parameters and process flows for different types and parts of tobacco leaves are determined according to empirical evaluation indexes such as sensory evaluation, the appearance quality of tobacco leaves, and the smell emitted during the fermentation process. The main characteristics of the Dominican cigar tobacco leaf fermentation process are that stem removal and grading are synchronized with fermentation, which is suitable for the fermentation and processing of binder tobacco leaves and belongs to high-intensity and long-cycle fermentation. The domestic cigar tobacco leaves basically adopt the stacking fermentation method, and the fermentation process flow includes processes such as removing the stalks and tying them into bundles, humidifying and reconditioning, and agricultural fermentation (stacking, turning the stack, and unstacking). The main difference between the fermentation processes of wrapper and binder tobacco leaves is the control difference of moisture and fermentation temperature.

[0004] By synthesizing the fermentation technologies of domestic and foreign cigar tobacco leaves, it can be found that the fermentation processes and procedures in each country have their own characteristics. The common characteristics are complex process flow, cumbersome operation, long cycle, and a large amount of labor required for operation. The development of cigar tobacco in China started relatively late, and the fermentation technology is basically applied while researching. Currently, there are mainly the following problems: (1) The current fermentation process flow is not systematic and the operation is not standardized. During the storage and fermentation of tobacco leaves, the mildew and breakage rates are high, and the quality of the tobacco leaves after fermentation is uneven, seriously affecting the quality stability of cigar tobacco leaves. (2) The scientific nature of the existing technical regulations is not strong, and the classification fermentation process flow is not clear. The fermentation technical regulations in each production area are limited to empirical exploration, and the quality stability of tobacco leaf fermentation is poor. Especially, the same stacking fermentation method is used for both wrapper and binder tobacco leaves, resulting in poor color uniformity and integrity of the wrapper tobacco leaves after fermentation, restricting the yield and quality traits formation of high-quality wrapper. (3) The boundary between agricultural fermentation and industrial fermentation is not clear, and a complete and continuous fermentation technical regulation has not been formed. Currently, the goals and evaluation indicators of agricultural fermentation and industrial fermentation have not formed a unified standard, resulting in large differences in fermentation degrees in different production areas, low homogenization level of the quality of tobacco leaves after agricultural fermentation, and bringing great difficulties to industrial use. Summary of the Invention

[0005] To solve the above technical problems, the present application provides a fermentation method for cigar wrapper tobacco leaves and cigar tobacco leaves, optimizing the fermentation process flow, improving the quality of wrapper tobacco leaves, and enhancing production efficiency.

[0006] The technical solutions provided by the present application are as follows:

[0007] A fermentation method for cigar wrapper tobacco leaves, comprising the following steps:

[0008] Primary fermentation of raw wrapper tobacco:

[0009] After being taken off the stick, the raw wrapper tobacco is packed into boxes according to the tobacco leaf positions and undergoes primary fermentation. The fermentation temperature for the lower leaves is 35 - 37 °C, the fermentation temperature for the middle leaves is 36 - 38 °C, and the fermentation temperature for the upper leaves is 38 - 40 °C. The fermentation time is not less than 15 days. After the primary fermentation is completed, the tobacco boxes are cooled to room temperature to terminate the fermentation;

[0010] Secondary fermentation of wrapper tobacco leaves:

[0011] Control the moisture content of the tobacco leaves to be 20% - 22%, sort the tobacco leaves and tie them into bundles, humidify and condition to make the moisture content of the tobacco leaves 24% - 26%, balance the moisture, ensure the uniformity of the moisture of the tobacco leaves within the bundle, place the tobacco leaves in boxes for secondary fermentation, the fermentation temperature is 38 - 40 °C, and ferment for 30 - 50 days. After the secondary fermentation is completed, the tobacco boxes are cooled to room temperature to terminate the fermentation;

[0012] Aging and curing:

[0013] Age the tobacco leaves at room temperature with a relative environmental humidity of 65%-70% for 2-5 months.

[0014] Preferably, during the first fermentation, control the water content of the tobacco leaves at 20%-22% and tie them into bundles after taking them off the poles.

[0015] Preferably, during the first fermentation, the environmental temperature where the tobacco boxes are located is above 34°C and the relative humidity is 80%-85%.

[0016] Preferably, during the first fermentation and the second fermentation, when the temperature of the tobacco box exceeds the fermentation temperature, cool the tobacco box to 31-34°C and then put it back to continue fermentation.

[0017] Preferably, conduct insecticidal treatment on the environment before the second fermentation.

[0018] Preferably, during the second fermentation, the moisture balance time is 1-2h.

[0019] Preferably, during the second fermentation, when packing the tobacco leaves into the boxes, separate the heads of each layer of tobacco bundles with paper.

[0020] Preferably, during the second fermentation, when placing, the height of each stack should not exceed the height of 5 such tobacco boxes.

[0021] Preferably, during the second fermentation, the environmental temperature where the tobacco boxes are located is above 34°C and the relative humidity is 80%-85%.

[0022] A kind of cigar tobacco leaf, which is the tobacco leaf obtained by the fermentation method of any one of the above-mentioned cigar wrapper tobacco leaves.

[0023] The beneficial effects of this application include:

[0024] 1) This application systematically constructs a fermentation process for cigar wrapper tobacco leaves suitable for various domestic production areas, which can improve the wrapper output rate and homogenization degree of fermented cigar tobacco leaves, and achieve seamless connection between agricultural production and industrial use of cigar tobacco leaves.

[0025] 2) The constant temperature and humidity fermentation method of this application can make up for the technical shortcomings of domestic wrapper tobacco leaf fermentation, ensure the supply quality and supply efficiency, improve the processing production benefit, and reduce the labor employment and production cost in the fermentation processing operation links.

[0026] 3) The tobacco leaves of this application can better maintain the integrity of the tobacco leaves, have better uniformity, luster and tissue structure, and the tobacco leaf quality is high.

[0027] 4) This application greatly reduces the mildew and breakage rate during the fermentation of wrapper tobacco leaves, and effectively improves the stability and consistency of the tobacco leaf quality.

[0028] 5) This application effectively solves the problem of the unclear technological process of domestic cigar tobacco leaf classification and fermentation, clarifies the differential fermentation processes of wrapper and binder tobacco leaves, so as to improve the quality of the wrapper and promote the high-end development of the domestic cigar industry. Detailed implementation manners

[0029] In order to enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of this application.

[0030] A fermentation method for cigar wrapper tobacco leaves includes the following steps:

[0031] Primary fermentation of raw wrapper tobacco:

[0032] Control the water content of the tobacco leaves to be 20%-22%, take them off the poles, and then pack the raw wrapper tobacco by tobacco leaf position respectively for primary fermentation. The ambient temperature where the tobacco boxes are located is above 34°C, and the relative humidity is 80%-85%. The fermentation temperature of the lower leaves is 35-37°C, the fermentation temperature of the middle leaves is 36-38°C, and the fermentation temperature of the upper leaves is 38-40°C. The fermentation time is not less than 15 days. After the primary fermentation is completed, cool the tobacco boxes to room temperature to terminate the fermentation. If the fermentation temperature of the tobacco leaves is too high, the toughness of the tobacco leaves will become poor and the aroma substances will be severely lost. If the fermentation temperature is too low, the degradation of macromolecular substances will be insufficient and the fermentation degree will be insufficient.

[0033] Secondary fermentation of wrapper tobacco leaves:

[0034] Carry out insecticidal treatment on the environment. Two methods, phosphine aluminum tent fumigation and chemical spraying, can be combined for insecticidal treatment. Control the water content of the tobacco leaves to be 20%-22%, sort and tie them into bundles, humidify and recondition to make the water content of the tobacco leaves 24%-26%, balance the moisture for 1-2 hours to ensure uniform moisture in the bundles, pack the tobacco leaves into boxes, and separate the heads of each layer of tobacco bundles with paper. When placing, each stack should be placed no more than the height of 5 tobacco boxes. The ambient temperature where the tobacco boxes are located is above 34°C, and the relative humidity is 80%-85%.

[0035] Carry out secondary fermentation. The fermentation temperature is 38-40°C, and the fermentation lasts for 30-50 days. After the secondary fermentation is completed, cool the tobacco boxes to room temperature to terminate the fermentation. If the fermentation temperature of the tobacco leaves is too high, the toughness of the tobacco leaves will become poor and the color will deepen, resulting in poor uniformity. If the fermentation temperature is too low, the degradation of macromolecular substances will be insufficient and the fermentation degree will be insufficient.

[0036] Aging and maintenance:

[0037] The tobacco leaves are aged at room temperature with the relative environmental humidity of 65%-70% for 2-5 months.

[0038] The ambient temperature and relative humidity of the two fermentation tobacco boxes are constant, which is conducive to ensuring the stability of the quality of the wrapper tobacco leaves and improving production efficiency.

[0039] For the first fermentation and the second fermentation, when the temperature of the tobacco box exceeds the fermentation temperature, the tobacco box is cooled to 31-34 °C and then put back for continuous fermentation.

[0040] Example 1

[0041] The test varieties are Yunxue No. 2 and Yunxue No. 39, and the planting location is in the World Tobacco Variety Garden of Chengjiang, Yuxi.

[0042] A fermentation method for the wrapper tobacco leaves of cigars, comprising the following steps:

[0043] I. Primary fermentation of the original wrapper tobacco:

[0044] 1. Unhanging the tobacco

[0045] After the cigar tobacco leaves are completely dry-cured, the curing barn is opened in the early morning for natural rewetting or artificial ultrasonic atomization humidification rewetting, and the water content of the tobacco leaves is controlled at 20%-22%. The empirical judgment method for suitable moisture is that after squeezing the tobacco leaves tightly by hand and then loosening, the tobacco leaves will slowly return to their original state. The unhanging operation should be carried out during the period with higher humidity in the early morning, and the tobacco leaves with a water content exceeding 22% cannot be unhung. The tobacco leaves are harvested by parts and the unusable tobacco leaves such as "green, yellow, variegated, miscellaneous, moldy, rotten" are removed.

[0046] 2. Packing the original wrapper tobacco into boxes

[0047] The tobacco is classified and packed according to the tobacco leaf parts. The length × width × height of the carton = 960 mm × 650 mm × 550 mm, and each tobacco box contains 20-25 kg. The tobacco loaded should not exceed the edge of the box, and there should be no protrusions on the surface when sealing the box. The top of the last layer is covered with kraft paper or cardboard, and the box is sealed with materials such as tape, cloth strip or hemp rope. A plastic pipe with a diameter of about 1-2 cm is placed in every 5 boxes for placing a thermometer and a hygrometer later.

[0048] 3. Arranging the tobacco boxes

[0049] The pallet boards are placed longitudinally according to the layout of the curing barn. The distance between the cartons should be 10 cm. The height of each stack should not exceed 5 boxes. The tobacco box at the middle position of each stack of tobacco leaves is ensured to be the box for placing the thermometer and the hygrometer. An aisle is left between each row of tobacco boxes for observing and recording the temperature and humidity changes at the center of the tobacco box.

[0050] 4. Environmental control

[0051] The indoor temperature of the curing house is stable at 34°C; the indoor humidity should be stable at 85%.

[0052] 5. Fermentation Temperature Control and Operation

[0053] The fermentation temperature for the lower leaves is 35 - 37°C, for the middle leaves is 36 - 38°C, and for the upper leaves is 38 - 40°C. The fermentation time is 15 days. Observe and record the temperature at the center of the tobacco box regularly every day. If the temperature of the tobacco box exceeds the preset fermentation temperature, move the entire batch of boxes containing tobacco leaves out of the curing house for cooling. When the temperature of the tobacco box drops to 31 - 34°C, transfer it back into the curing house to continue fermentation. When the color of the tobacco leaves is uniform, the waxy texture on the leaf surface and the greenish odor weaken, and it has the characteristics of high-quality wrapper tobacco leaves, indicating that the tobacco leaves have completed fermentation. Then move the boxes out of the fermentation house and cool them to room temperature to terminate the fermentation.

[0054] II. Secondary Fermentation of Wrapper Tobacco Leaves

[0055] 1. Insect Control

[0056] Use two methods for pest control: aluminum phosphide tent fumigation and spraying of pesticides in the warehouse space. The phosphine gas released by the aluminum phosphide used in tent fumigation has relatively strong penetrability and has a good effect on killing pests inside the tobacco leaf stacks and tobacco-related materials. For pests in the warehouse space, use pyrethrum, Lexion, pirimiphos-methyl and other hygienic-grade drugs for spraying. The combination of these two pest control methods can achieve the effect of killing all pests in the fermentation warehouse.

[0057] 2. Sorting and Tying into Bundles

[0058] Sort out 50 kg of wrapper tobacco leaves. Control the moisture content of the tobacco leaves at 20% - 22%. The empirical judgment method is that when the tobacco leaves are tightly grasped by hand and then released, the tobacco leaves will slowly return to their original shape. Sort the original cigar tobacco leaves into wrapper tobacco leaves according to quality requirements. The specific quality requirements refer to the "Grade Standards for Handover between Industrial and Commercial Sectors of Cigar Tobacco Leaves" (YCT 588 - 2021). Remove the moldy, greenish-colored, and severely damaged tobacco leaves. Tie the sorted tobacco leaves into bundles of about 25 pieces each with cotton thread or hemp thread at 2 - 3 cm from the base of the tobacco bundle.

[0059] 3. Humidifying and Moisture Conditioning

[0060] During fermentation, it is necessary to increase the moisture content of the tobacco leaves to meet the fermentation conditions of cigar tobacco leaves. Use ultrasonic atomization for moisture conditioning for 30 minutes. Hang the tobacco leaves directly on the mobile moisture balance rack and use ultrasonic atomization to adjust the moisture content of the tobacco leaves to 24% - 26%.

[0061] 4. Moisture Balance

[0062] The bundled tobacco after moisture regain needs a period of moisture balance to ensure that there are no water droplets or water stains on the surface of the tobacco leaves and the moisture in the bundled tobacco is evenly distributed. That is, under the condition of controllable temperature and humidity, the humidified and regained tobacco leaves are hung on the balance rack and placed in the moisture balance chamber for 1 - 2 hours.

[0063] 5. Cigar wrapper packing

[0064] Lay kraft paper or cardboard at the bottom of the carton. For the first layer, the heads of the tobacco bundles lean against both ends of the carton; for the second layer, the heads of the tobacco bundles are placed on a strip of paper about 10 - 12 cm wide to avoid damaging the lower - layer tobacco leaves by the tobacco heads and at the same time cover the gaps left when placing the first layer. After the second layer, place another piece of paper on the heads of the tobacco bundles, and then place the heads of the third - layer tobacco bundles at both ends of the carton; the placement process of the tobacco bundles in the remaining layers is repeated as above for packing. The packed tobacco should not exceed the edges of the box, and there should be no protrusions on the surface when sealing the box. Cover the top of the last layer with kraft paper or cardboard. Seal the box with tape, cloth strips or hemp ropes, etc. Place a plastic pipe with a diameter of about 1 - 2 cm in every 5 boxes for placing a thermometer and hygrometer later.

[0065] 6. Carton placement

[0066] Place the pallet boards longitudinally according to the layout of the fermentation room. There should be a 10 - cm gap between the cartons. Each stack should not exceed the height of 5 boxes. Ensure that the carton at the middle position of each stack of tobacco is the one for placing the thermometer and hygrometer. Leave an aisle between each row of cartons to facilitate observing and recording the temperature and humidity changes at the center of the cartons.

[0067] 7. Environment control

[0068] The indoor temperature of the fermentation room is stabilized at 38°C; the indoor humidity should be stabilized at 85%.

[0069] 8. Fermentation temperature control and operation

[0070] Carry out secondary fermentation, and the fermentation temperature is controlled at 38 - 40°C. Observe and record the temperature at the center of the cartons regularly every day. If the temperature of the cartons exceeds the preset fermentation temperature, move the entire batch of cartons filled with tobacco leaves out of the fermentation room for cooling. When the temperature of the cartons drops to 31 - 34°C, transfer them back into the fermentation room to continue fermentation. After 30 days of fermentation, the color uniformity, maturity, and tissue structure of the tobacco leaves meet the characteristics of high - quality cigar wrapper tobacco leaves, and the green and miscellaneous odors disappear, indicating that the tobacco leaves have completed fermentation. Move the cartons out of the fermentation room and cool them to room temperature to terminate the fermentation.

[0071] III. Aging and curing:

[0072] Age the tobacco leaves at room temperature with a relative humidity of 65% for 2 months. During the whole process, it is necessary to control the moisture of the tobacco leaves well to ensure that the tobacco leaves are not broken, not wet, and not moldy; the tobacco leaves should always remain in a soft state, and avoid excessive drying due to too low moisture, which may cause irreversible deterioration of their quality. After 2 months of aging, the tobacco leaves can be used in the formulation.

[0073] Record the temperature every day at 8:00, 12:00, 14:00, and 17:00 during the whole fermentation process.

[0074] The yield rate of the cigar wrapper = the weight of the cigar wrapper tobacco leaves / the weight of the fermented tobacco leaves * 100%. The yield rate of the cigar wrapper in Example 1 was calculated to be 32.6%.

[0075] Control example

[0076] The test variety is the same as that in Example 1.

[0077] The fermentation of the cigar wrapper tobacco leaves of cigars includes the following steps:

[0078] I. Primary fermentation of the original cigar wrapper tobacco: The same as in Example 1.

[0079] II. Sort out 50 kg of cigar wrapper tobacco leaves. Adopt the stacking fermentation method for stacking fermentation treatment. The operation process of the fermentation process follows the "Technical Regulations for Agricultural Stacking Fermentation of Cigar Tobacco Leaves" (DB53 / T 1303 - 2024). The indoor temperature of the fermentation room is 15 - 25°C, and the indoor humidity is 60% - 70%.

[0080] The yield rate of the cigar wrapper in the control example was calculated to be 21.08%.

[0081] Evaluation of the appearance quality and sensory quality of cigar tobacco leaves by smoking.

[0082] Appearance quality evaluation: Adopt a 10 - point scoring rule to assign scores to 8 indicators such as maturity, oil content, identity, integrity, uniformity, luster, vein pattern, and tissue structure of 30 tobacco leaves in the examples and control examples respectively. The 8 indicators are all divided into 3 grades, the first grade (8 - 10 points), the second grade (5 - 7 points), and the third grade (1 - 4 points); an appearance quality evaluation group composed of 6 professional grading personnel scores each tobacco leaf and calculates the average value. Sensory quality evaluation: A smoking evaluation group composed of 5 cigar sensory evaluation experts uses the "Evaluation Form for Sensory Quality and Style of Domestic Cigar Tobacco Leaves" proposed by the Cigar Tobacco Technology Innovation Center of the tobacco industry to score the style characteristics (divided into significant, relatively significant, medium, weak, and very weak), concentration (rich, relatively rich, medium, light, and very light), 19 aroma characteristics (5 - point system, with a scoring unit of 1 point), 8 kinds of off - flavors (5 - point system, with a scoring unit of 1 point), and quality characteristics (9 - point system, with a scoring unit of 0.5 point), including aroma, smoke, aftertaste, and burning characteristics of the samples with different humidification treatments.

[0083] The results of the appearance quality test are shown in Table 1.

[0084] Table 1

[0085] Experimental group Example 1 Comparative example Maturity 6.2±0.1b 8.3±0.1a Oil content 8.4±0.1a 7.2±0.1b Identity 8.1±0.1a 8.0±0.2a Integrity 8.4±0.1a 7.3±0.1b Uniformity 7.9±0.2a 6.7±0.2b Luster 8.1±0.1a 7.2±0.1b Vein pattern 8.1±0.1a 7.9±0.1a Microstructure 7.8±0.2a 6.5±0.1b

[0086] Analyze the appearance quality of the tobacco leaves after being fermented by two fermentation processes. It can be seen from Table 1 that the scores of the oil content, integrity, uniformity, luster, and leaf structure of the tobacco leaves treated by the constant temperature and humidity fermentation process are significantly higher than those of the stacking fermentation process. The results show that using the fermentation process of this application to treat tobacco leaves can better maintain the integrity of the tobacco leaves and improve the uniformity, luster, and tissue structure of the wrapper tobacco leaves.

[0087] The results of the sensory quality test are shown in Table 2.

[0088] Table 2

[0089]

[0090] Analyze the sensory quality evaluation indexes such as the style, aroma characteristics, concentration, and foreign odors of the tobacco leaves after being fermented by two fermentation processes. It can be seen from Table 2 that the main aroma of the tobacco leaves treated by this application is honey-sweet aroma, supplemented by coffee aroma, floral aroma, resin aroma, and baking aroma. The main aroma of the tobacco leaves treated by stacking fermentation is caramel-sweet aroma, supplemented by nut aroma, coffee aroma, and resin aroma. The types and score values of the foreign odors of the tobacco leaves treated by this application are slightly more or greater than those of the stacking fermentation process. The tobacco leaves treated by this application show three types of foreign odors: protein odor, green foreign odor, and burnt odor, and the scores are all greater than 2 points; while the stacking fermentation treatment only has two types of foreign odors: green foreign odor and burnt odor, and the score value is 1 point.

[0091] The results of the smoke quality test are shown in Table 3.

[0092] Table 3

[0093]

[0094] Analyze the smoke quality evaluation indexes of the tobacco leaves after being fermented by two fermentation processes. It can be seen from Table 3 that the score values of the aroma quantity, richness, fineness, sweetness, and aftertaste of the tobacco leaves treated by this application are slightly higher than those of the stacking fermentation treatment. Based on the above smoke quality evaluation indexes, it can be clearly seen that there is little difference in the smoke sensory quality of the cigar tobacco leaves fermented by the two fermentation processes. The main difference is that stacking fermentation can improve the maturity, cleanliness, combustibility, and ash color of the smoke, while in-container fermentation can improve the aroma quantity, richness, fineness, sweetness, and aftertaste of the tobacco leaves.

[0095] Comparative test on the physical and chemical components of cigar tobacco leaves.

[0096] Determination of physical property indexes: The determined physical indexes include leaf filling value, leaf equilibrium moisture content, leaf thickness, leaf tensile strength, and leaf surface density. The determination methods all refer to "Primary Processing of Tobacco Raw Materials". Determination of chemical components: The main chemical component indexes determined are the contents of total sugar, reducing sugar, total nitrogen, protein, starch, potassium oxide, chloride ion, pectin, lignin, cellulose, ash, and pH value in cigar tobacco leaves determined by continuous flow method or ion chromatography method. The determination methods refer to the tobacco industry standards.

[0097] The determination results of physical property indexes are shown in Table 4.

[0098] Table 4

[0099]

[0100] The results of variance analysis of the physical property indexes of tobacco leaves after fermentation by two fermentation methods show that compared with bulk fermentation, the tensile strength value and leaf surface density of box fermentation are significantly increased. Considering the variation law of physical property indexes during the fermentation process of cigar tobacco leaves, the results show that this application belongs to mild fermentation, which can maintain the tensile strength of tobacco leaves. The wrapper has a high requirement for the tensile strength value, indicating that box fermentation at constant temperature and humidity is suitable for the fermentation and processing of wrapper tobacco leaves.

[0101] The determination results of conventional chemical component indexes are shown in Table 5.

[0102] Table 5

[0103]

[0104] By analyzing the conventional chemical component indexes of tobacco leaves after fermentation by two fermentation methods. It can be seen from Table 5 that compared with the bulk fermentation method, the total nitrogen content is significantly higher than that of the tobacco leaves treated by bulk fermentation, while the contents of total sugar, potassium, pH value, cellulose, and lignin are significantly lower than those of the tobacco leaves treated by bulk fermentation. The significant difference in pH value also proves that bulk fermentation has experienced deep fermentation; there is no significant difference in the contents of reducing sugar, protein, ash, and pectin between the two fermentation methods.

[0105] Although bulk fermentation can accelerate the fermentation speed of cigar tobacco leaves and promote the metabolism and synthesis of nicotine in tobacco leaves, for wrapper tobacco leaves, the focus is on the appearance quality. A rapid fermentation process will lead to poor uniformity, luster, and tissue structure of tobacco leaves, reducing the wrapper yield. Generally speaking, the fermentation method of this application is very suitable for the fermentation and processing of wrapper tobacco leaves, with a high wrapper yield and high tobacco leaf quality.

[0106] The determination results of the contents of 6 alkaloids and 4 tobacco-specific nitrosamines (TSNAs) are shown in Table 6.

[0107] Table 6

[0108]

[0109] As can be seen from Table 6, the contents of nicotine, nornicotine, anabasine, neonicotine and volatile base in the tobacco leaves of Example 1 are significantly higher than those of the tobacco leaves in the comparative example; while myosmine, N-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N-nitroso neonicotine (NAT) and N-nitroso anabasine (NAB) are significantly lower than those of the tobacco leaves in the comparative example.

[0110] The comparative analysis results of labor employment are shown in Table 7.

[0111] Table 7

[0112]

[0113]

[0114] By comparing the labor employment quantities in each operation link of processing tobacco leaves by two fermentation methods. The conventional stacking fermentation process has a large amount of labor employment in the stacking and turning piles links, and there are also repeated operations in the sorting and grading process; while the present application simplifies the fermentation processing link and avoids redundant operation processes. As can be seen from Table 7, the total labor employment for processing 1 ton of tobacco leaves by the conventional stacking fermentation process is 131.26, while the average labor employment for the constant temperature and humidity box fermentation is only 56.18, and the labor employment quantity is reduced by 75.08, greatly reducing the labor employment cost of tobacco leaf fermentation processing and improving the efficiency of cigar tobacco leaf fermentation processing.

[0115] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. The embodiments are merely examples for clearly illustrating the technical solutions of the present application and are not intended to limit the present application.

Claims

1. A fermentation method for cigar wrapper tobacco leaves, characterized in that: The following steps are involved: Primary fermentation of cigar wrapper tobacco: After the tobacco leaves are removed from the poles, the original wrapper tobacco is packed into boxes according to the tobacco leaf parts and fermented once. The fermentation temperature of the lower leaves is 35-37°C, the fermentation temperature of the middle leaves is 36-38°C, and the fermentation temperature of the upper leaves is 38-40°C. The fermentation time is not less than 15 days. After the primary fermentation is completed, the tobacco box is cooled to room temperature to terminate the fermentation. Secondary fermentation of wrapper tobacco leaves: The moisture content of the tobacco leaves is controlled to be 20%-22%, the tobacco leaves are sorted and bundled, and the moisture content of the tobacco leaves is 24%-26% by humidification and moisture regeneration, and the moisture balance is ensured to ensure that the moisture of the tobacco leaves in the bundle is uniform, and the tobacco leaves are packed and placed in boxes for secondary fermentation at a fermentation temperature of 38-40° C. for 30-50 days. After the secondary fermentation is completed, the tobacco box is cooled to room temperature to terminate the fermentation; Alcoholization maintenance: The tobacco leaves are aged at room temperature with a relative humidity of 65% to 70% for 2 to 5 months.

2. The fermentation method of cigar wrapper tobacco according to claim 1, characterized in that: During the primary fermentation, the moisture content of the tobacco leaves is controlled at 20%-22%, and the tobacco leaves are put on the poles and tied into bundles.

3. The fermentation method of cigar wrapper tobacco according to claim 1, characterized in that: During the primary fermentation, the ambient temperature of the smoke box is above 34° C., and the relative humidity is 80%-85%.

4. The fermentation method of cigar wrapper tobacco according to claim 1, characterized in that: During the primary fermentation and the secondary fermentation, when the temperature of the smoke box exceeds the fermentation temperature, the smoke box is cooled to 31-34° C. and then put back to continue the fermentation.

5. The fermentation method of cigar wrapper tobacco according to claim 1, characterized in that: The environment is disinfected before the secondary fermentation.

6. The fermentation method of cigar wrapper tobacco according to claim 1, characterized in that: During the secondary fermentation, the water balance time is 1-2h.

7. The fermentation method of cigar wrapper tobacco according to claim 1, characterized in that: During the secondary fermentation, when the tobacco leaves are packed into boxes, the heads of each layer of tobacco bundles are separated by paper.

8. The fermentation method of cigar wrapper tobacco according to claim 1, characterized in that: During the secondary fermentation, when placing the tobacco, each pile should be placed to a height of no more than 5 of the above-mentioned tobacco boxes.

9. The fermentation method of cigar wrapper tobacco leaves according to claim 1, characterized in that: During the secondary fermentation, the ambient temperature of the smoke box is above 34° C., and the relative humidity is 80%-85%.

10. A cigar tobacco leaf, characterized in that: The tobacco leaf is obtained by the fermentation method of cigar wrapper tobacco leaf according to any one of claims 1 to 9.

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