Method based on nutrition regulation and matched baking of upper leaves of flue-cured tobacco

Abstract

The invention discloses a flue-cured tobacco upper leaf nutrition regulation and matched flue-curing method, which comprises the following steps: S1, primary spraying: spraying a leaf surface regulator I in 3-5 days after middle tobacco leaves are mature and harvested; s2, secondary spraying: spraying a leaf surface conditioning agent II 1-2 days before the upper tobacco leaves are mature and harvested; s3, baking: baking by adopting a baking process of'one low, one high and one long 'in a yellowing period, 'one slow, one low and one long' in a color fixing period and'one slow, one long and one low 'in a stem drying period; the method can effectively improve the quality and baking characteristics of the upper fresh tobacco leaves, reduce diseases of the upper tobacco leaves in the field, and improve the quality of the baked upper tobacco leaves.

Description

Technical Field

[0001] The invention relates to a method based on nutritional regulation and matching baking of upper leaves of flue-cured tobacco, belonging to the technical field of tobacco leaf harvesting and curing. Background Art

[0002] With the internationalization of cigarette brands and the continuous upgrading of big brand effects, the cigarette industry has an increasing demand for high-quality tobacco raw materials. With the adjustment of tobacco leaf structure, the proportion of upper tobacco leaves is as high as more than 45%, while the proportion of purchases in many tobacco areas is less than 30%. The quality of upper tobacco leaves directly affects the long-term development of the cigarette industry. At present, there are many problems with upper tobacco leaves, such as the upper fresh tobacco leaves are not resistant to ripening, are susceptible to diseases, have poor maturity, and fall yellow unevenly, which can easily lead to ash hanging on the baked tobacco leaves, light color, baking slag, and insufficient aroma, etc., making it difficult to meet the demand of the cigarette industry for high-quality tobacco raw materials. Therefore, improving the nutritional balance and baking characteristics of the upper fresh tobacco in the field is an important guarantee for improving the baking quality of the upper tobacco leaves.

[0003] From the current situation, spraying potassium dihydrogen phosphate and sucrose solution on the leaves can improve the quality and nutritional conditions of the upper tobacco leaves under chilling conditions (published invention patents: flue-cured tobacco cultivation management and baking method based on potassium dihydrogen phosphate and sucrose to alleviate chilling damage; baking method to reduce the loss of low temperature chilling damage to safflower Dajinyuan tobacco leaves in high altitude areas); spraying potassium nitrate 0.2-0.4kg / L, potassium dihydrogen phosphate 0.2-0.4kg / L, magnesium chloride 2.0-3.0g / L, calcium nitrate 5.0-6.0g / L , sodium tetraborate 0.5-1.5g / L, potassium humate 0.2-0.6kg / L, abscisic acid 8-25mg / L, auxin 12-28mg / L, brassinolide 0.3-1.8mg / L, ethanol appropriate amount of regulator, can promote the ripening resistance of flue-cured tobacco in the field, the mature and yellowing of tobacco leaves are consistent, thereby improving the yield and quality of flue-cured tobacco leaves (disclosed invention patent: a field flue-cured tobacco regulator and its preparation method and application); by spraying nitrogen fertilizer, potassium dihydrogen phosphate, potassium sulfate, molybdenum A special foliar fertilizer composed of ammonium sulfate, oligosaccharides, gibberellins, and auxiliary ingredients can improve the quality of the upper leaves of flue-cured tobacco (a patent for invention has been published: a special foliar fertilizer for improving the quality of the upper leaves of flue-cured tobacco and its preparation method and application); by leaving 2-3 axillary buds from the grown axillary buds after topping the tobacco leaves, and then harvesting and baking them all at once after the upper leaves are mature, the ash on the upper leaves can be reduced (a patent for invention has been published: a method for harvesting and baking to reduce the ash on the upper leaves); by optimizing fertilization and ridging, adjusting cultivation measures, spraying exogenous Field management methods such as removing pollutants, optimizing topping measures, blocking the transport of assimilates, and delaying the one-time harvest of upper leaves can improve the availability of the upper leaves of flue-cured tobacco NC297 (published invention patent: a field management method for improving the availability of the upper leaves of flue-cured tobacco NC297), but these treatment schemes still cannot effectively solve the problems existing in the upper fresh tobacco leaves, especially the poor baking resistance of fresh tobacco leaves, susceptibility to disease infection, easy to get dust, baked stiff, baked green, and baked stale, so more complete and effective upper tobacco leaf processing supporting technical measures are needed. Summary of the invention

[0004] Based on the above, the present invention provides a method based on nutritional regulation and matching baking of upper leaves of flue-cured tobacco, which can significantly improve the baking resistance of upper fresh tobacco and the quality of cured tobacco leaves.

[0005] The technical solution of the present invention is: a method based on the nutritional regulation and matching baking of the upper leaves of flue-cured tobacco, comprising:

[0006] S1 one-time spraying: spray leaf regulator 1 on the 3rd to 5th day after the middle tobacco leaves mature and are harvested;

[0007] S2 Secondary spraying: 1 to 2 days before the upper tobacco leaves mature and are harvested, spray the leaf regulator II;

[0008] S3 baking.

[0009] Preferably, the foliar regulator is composed of 3.0% to 5.0% glucose, 80 to 150 μmol / L melatonin and 0.6% to 1.0% α-aminoisobutyric acid solution, and the spraying amount is 10 to 20 kg per mu.

[0010] Preferably, the second foliar regulator is composed of 3.0% to 5.0% glucose and 80 to 150 μmol / L melatonin solution, and the spraying amount is 10 to 20 kg per mu.

[0011] Preferably, the baking process is as follows:

[0012] S3-1, yellowing stage: after ignition, the dry bulb temperature is raised to 32-34°C and the wet bulb temperature is 32-33°C at a rate of 1°C / h, and the tobacco leaves are baked at a steady temperature until they turn 10% to 20% yellow; then, the dry bulb temperature is raised to 35-36°C and the wet bulb temperature is 34-35°C at a rate of 1°C / h, and the tobacco leaves are baked at a steady temperature until they turn 20% to 30% yellow; then, the dry bulb temperature is raised to 39-40°C and the wet bulb temperature is raised to 37-39°C at a rate of 1°C / h, and the baking time is extended by 6-10h, and the tobacco leaves are baked at a steady temperature until they turn 80% to 90% yellow and become soft; then, the dry bulb temperature is raised to 42°C and the wet bulb temperature is 35-37°C at a rate of 1°C / 2-3h, and the tobacco leaves are baked at a steady temperature for 10-15h, until the leaves turn yellow, veins turn blue, and the leaves are fully withered and soft;

[0013] S3-2, color fixing period: increase the dry bulb temperature to 44℃ at a rate of 1℃ / 3~4h, reduce the wet bulb temperature to 35~36℃, and bake at a steady temperature for 6~10h until the main tendons of the tobacco leaf tips turn yellow and the tobacco leaf tips curl; extend the baking time at 46~54℃ for 6~10h to promote the transformation of tobacco leaf internal substances and the generation of aroma substances, increase the dry bulb temperature to 46~47℃ at a rate of 1℃ / 2~3h, the wet bulb temperature is 36~37℃, and bake at a steady temperature 5-6h, until more than 2 / 3 of the tobacco leaves turn yellow and more than 1 / 2 of the leaves shrink and dry; then, raise the dry-bulb temperature to 49-51℃ at a rate of 1℃ / 2h, and the wet-bulb temperature to 37-38℃, and bake at a steady temperature for 6-10h until the tobacco leaves turn yellow and more than 2 / 3 of the leaves are dry; then, raise the dry-bulb temperature to 54℃ at a rate of 1℃ / 2h, and the wet-bulb temperature to 38-39℃, and bake at a steady temperature until more than 1 / 3 of the tobacco leaves shrink and the leaves are dry;

[0014] S3-3, dry tobacco period: increase the dry bulb temperature to 56-60℃ at a rate of 1℃ / 2-3h, extend the steady temperature baking time to 8-12h, control the wet bulb temperature at 39-40℃, and bake at a steady temperature until more than 1 / 2 of the tobacco leaves are dry; then, keep the wet bulb temperature unchanged, increase the dry bulb temperature to 65-66℃ at a rate of 1℃ / h, and extend the steady temperature baking time until all the tobacco leaves are dry.

[0015] Beneficial effects of the present invention:

[0016] 1. Before harvesting the upper tobacco leaves, spraying the leaf conditioner twice can effectively improve the quality and baking characteristics of the upper fresh tobacco in the field, reduce the occurrence of upper leaf diseases, and improve the uniformity of the upper tobacco leaves maturing and yellowing, thereby improving the quality of the upper tobacco leaves after baking. Specifically, glucose solution is an important regulatory substance for plant nutrition, gibberellin and melatonin are plant hormone substances that play an important regulatory role in the growth and development of tobacco leaves, and α-aminoisobutyric acid has a bactericidal effect and delays leaf senescence. By spraying the leaf conditioner 1 composed of glucose, melatonin and α-aminoisobutyric acid solution, the nutrition of the upper tobacco leaves can be balanced, the baking resistance of the tobacco leaves can be improved, and the occurrence of diseases and pests can be prevented and controlled; by spraying the leaf conditioner 2 composed of glucose and melatonin, the nutrition of the upper tobacco leaves can be balanced, thereby improving the baking resistance and baking characteristics of the upper fresh tobacco leaves.

[0017] 2. When baking the upper tobacco leaves, the baking process of "one low, one high, and one long" during the yellowing period, "one slow, one low, and one long" during the color fixing period, and "one slow, one long, and one low" during the dry tendon period can improve the grade structure and economic characteristics of the baked tobacco leaves, improve the coordination of the chemical composition of the baked tobacco leaves, and improve the aroma quality and sensory quality of the baked tobacco leaves. Specifically, "one low, one high, and one long" during the yellowing period refers to lowering the ignition temperature by 1 to 2°C, increasing the wet bulb temperature of the main yellowing dry bulb temperature of 39 to 40°C by 1 to 2°C, and extending the baking time of the tobacco leaves at the main yellowing dry bulb temperature by 6 to 10 hours. The yellowing period is conducive to the gentle transformation of internal substances, thereby effectively avoiding the tobacco leaves from being baked green or stale due to excessively fast heating and high temperature. A long yellowing period is conducive to maintaining the flexibility of tobacco leaves, and can prevent the appearance of green tobacco or green smoke due to excessive water loss. Especially for tobacco leaves treated with melatonin, the physiological activity of their cells has changed. Appropriate humidity can ensure the normal metabolism and transportation of substances in tobacco leaf cells, and is also conducive to the full transformation of tobacco leaf substances, and improves the accumulation of aroma substances in tobacco leaves after baking. A long yellowing period can ensure that tobacco leaves can turn yellow fully, which helps to achieve stable changes in tobacco leaf plastid pigments and other components, thereby making tobacco leaves turn yellow more evenly. The "slow, low and long" color fixing period refers to slowing down the dry bulb temperature rise rate, reducing the wet bulb temperature of 44°C by 1 to 2°C, and extending the baking time of 46 to 54°C tobacco leaves by 6 to 10 hours. A slow color fixing period can give tobacco leaves sufficient time to adapt to temperature changes and internal water migration during the color fixing process, which helps tobacco leaves maintain the wetness and color of the leaves during the slow water loss process, and at the same time promotes the full decomposition and transformation of macromolecular substances in the tobacco leaves. In addition, avoid the inconsistent drying speed of the surface and internal parts of tobacco leaves caused by rapid temperature changes, and reduce the occurrence of problems such as ash, stiffness and variegated colors of tobacco leaves. The purpose of water control is achieved by keeping the color fixation period low. Tobacco leaves with high moisture content are prone to ash when the temperature exceeds 45°C. This stage is mainly to discharge excess water and then increase the temperature to reduce the appearance of ash-hanging tobacco and variegated tobacco leaves. By making the color fixation period long, tobacco leaves can better complete these physiological and biochemical processes (46-54°C is the key stage for the formation and accumulation of tobacco aroma precursor substances), which is beneficial to improving the aroma quality of tobacco leaves after baking. The "slow, long and low" in the dry gluten period refers to slowing down the dry bulb temperature rise rate, raising the dry bulb temperature to 56-60°C at a rate of 1°C / 2-3h, extending the dry bulb temperature to 56-60°C for 4-6h (3-5h in conventional production), and reducing the wet bulb temperature in the dry gluten period by 1-2°C. A slow drying period can avoid excessive loss of tobacco aroma components due to too fast temperature rise, while ensuring that the main veins are fully and orderly dehydrated and dried. A long drying period can avoid excessive loss of tobacco aroma components due to too high temperature, while ensuring that the main veins are fully dried. A short drying period can dry the tobacco quickly, shorten the baking time, and reduce the loss of aroma substances. DETAILED DESCRIPTION

[0018] In order to make the above-mentioned purpose, features and advantages of the present invention more obvious and easy to understand, the specific implementation of the present invention is described in detail below. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific implementation disclosed below.

[0019] 1. Processing before picking upper tobacco leaves

[0020] Embodiment 1:

[0021] Before harvesting the upper tobacco leaves, follow these steps:

[0022] S1 one-time spraying: spray leaf regulator 1 on the 3rd to 5th day after the middle tobacco leaves mature and are harvested;

[0023] S2 Second spraying: Spray leaf conditioner 2 1 to 2 days before the upper tobacco leaves mature and are harvested.

[0024] Comparative Example 1:

[0025] Before the upper tobacco leaves were harvested, local routine production operations were followed as a control, i.e. no spraying treatment was performed.

[0026] Comparative Example 2:

[0027] On the 3rd to 5th day after the middle tobacco leaves mature and are harvested, spray the foliar conditioner 1, that is, only spray the foliar conditioner 1.

[0028] Comparative Example 3:

[0029] 1 to 2 days before the upper tobacco leaves mature and are harvested, spray the leaf conditioner 2, that is, only spray the leaf conditioner 2.

[0030] The experiment was conducted in Fuquan Base, Qiannan Prefecture, Guizhou Province from 2023 to 2024. The flue-cured tobacco variety tested was Yunyan 87, and the 15th to 16th leaf positions of the upper leaves were used as test materials. The test tobacco leaves were cultivated and managed in accordance with the standardized production of local high-quality tobacco leaves. The local conventional production operation was used as control example 1 (no spraying treatment), and only spraying foliar regulator 1 and foliar regulator 2 were used as control examples 2 and 3, respectively, and the present invention (Example 1) was used as the treatment group.

[0031] 1. Effects of different treatments on the quality and properties of fresh tobacco leaves at maturity

[0032] The quality of fresh tobacco leaves was counted when the 15th to 16th leaves of the upper leaves of each group matured. The following is an evaluation and analysis of each group of tobacco leaves from the aspects of softness, looseness, maturity resistance, fresh tobacco quality, baking resistance and proportion of diseased tobacco leaves. The results of the statistics of 50 fresh tobacco leaves are as follows.

[0033] Table 1 Effects of different treatments on the quality and properties of fresh tobacco leaves at maturity

[0034]

[0035] As can be seen from Table 2, spraying leaf conditioner 1 on the 3rd to 5th day after the middle tobacco leaves are harvested can effectively balance the nutrition of the upper tobacco leaves, improve the softness, looseness, ripening resistance, fresh tobacco quality and baking resistance of the upper leaves, and reduce the occurrence of diseased tobacco leaves in the upper part. Secondly, spraying leaf conditioner 2 1 to 2 days before the upper tobacco leaves are harvested can effectively balance the nutrition of the upper tobacco leaves, improve the softness, looseness, ripening resistance, fresh tobacco quality and baking resistance of the upper leaves. Combined with the two spraying of leaf conditioners, the quality of the upper fresh tobacco leaves is better overall. The results show that the method of the present invention can significantly improve the quality and baking characteristics of the upper tobacco leaves, which is significantly better than the control.

[0036] 2. Effects of different treatments on the baking resistance of upper tobacco leaves

[0037] When the 15th to 16th leaves of the upper leaves of each group matured, they were put into intensive curing barns to count the changes of tobacco leaves during the curing process. The test curing barns were standard intensive curing barns. The following is an evaluation and analysis of the treated and control tobacco leaves from the aspects of the time when the upper tobacco leaves turn yellow by 90% during curing, the activity of polyphenol oxidase (PPO) at 45°C during curing, the degree of ash hanging, and curing resistance. A total of 50 leaves were counted for the time when the tobacco leaves turn yellow by 90%, the degree of ash hanging at 45°C, and the curing resistance. The PPO activity at 45°C was measured 3 times, and the results are as follows.

[0038] Table 2 Effects of different treatments on the baking resistance of upper tobacco leaves

[0039]

[0040]

[0041] As shown in Table 2, spraying leaf conditioner 1 on the 3rd to 5th day after the middle tobacco leaves are harvested can effectively balance the nutrition of the upper tobacco leaves, improve the baking resistance of the upper leaves, delay the yellowing of tobacco leaves, reduce PPO activity, and reduce the occurrence of upper ash. Secondly, spraying leaf conditioner 2 1 to 2 days before the upper tobacco leaves are harvested can also effectively balance the nutrition of the upper tobacco leaves to a certain extent, improve the baking resistance of the upper leaves, delay the yellowing of tobacco leaves, reduce PPO activity, and reduce the occurrence of upper ash. Combined with the two spraying of leaf conditioners, the baking resistance of the upper fresh tobacco leaves is better overall.

[0042] 2. Baking process of upper tobacco leaves

[0043] Example 2: Baking process of the present invention

[0044] The baking process of the upper tobacco leaves is as follows:

[0045] S4-1, yellowing stage: after ignition, the dry bulb temperature is raised to 32°C at a rate of 1°C / h, the wet bulb temperature is 32°C, and the tobacco leaves are baked at a steady temperature until they turn 10% to 20% yellow; then, the dry bulb temperature is raised to 35°C at a rate of 1°C / h, the wet bulb temperature is 34°C, and the tobacco leaves are baked at a steady temperature until they turn 20% to 30% yellow; then, the dry bulb temperature is raised to 39°C at a rate of 1°C / h, the wet bulb temperature is raised to 37.5°C, the baking time is extended by 6h, and the tobacco leaves are baked at a steady temperature until they turn 80% yellow and become soft; then, the dry bulb temperature is raised to 42°C at a rate of 1°C / 2h, the wet bulb temperature is 36°C, and the tobacco leaves are baked at a steady temperature for 10h, until the leaves turn yellow, veins turn blue, and the leaves are fully withered and soft;

[0046] S4-2, color fixation period: increase the dry bulb temperature to 44℃ at a rate of 1℃ / 4h, reduce the wet bulb temperature to 36℃, and bake at a steady temperature for 8h until the main ribs at the tip of the tobacco leaves turn yellow and the tip of the tobacco leaves curl; extend the baking time at 46-54℃ for 10h to promote the transformation of internal substances in the tobacco leaves and the generation of aroma substances, increase the dry bulb temperature to 47℃ at a rate of 1℃ / 3h, the wet bulb temperature is 37℃, and bake at a steady temperature for 6h until more than 2 / 3 of the tobacco ribs turn yellow and more than 1 / 2 of the leaves shrink and dry; then, increase the dry bulb temperature to 50℃ at a rate of 1℃ / 2h, the wet bulb temperature is 37-38℃, and bake at a steady temperature for 6h until the tobacco ribs are completely yellow and more than 2 / 3 of the leaves are completely dry; then, increase the dry bulb temperature to 54℃ at a rate of 1℃ / 2h, the wet bulb temperature is 39℃, and bake at a steady temperature until more than 1 / 3 of the tobacco ribs shrink and the leaves are completely dry;

[0047] S4-3, tobacco stem drying stage: raise the dry-bulb temperature to 58°C at a rate of 1°C / 2h, extend the steady-temperature baking time to 8h, control the wet-bulb temperature at 40°C, and bake at a steady temperature until more than 1 / 2 of the tobacco stems are dry; thereafter, control the wet-bulb temperature unchanged, raise the dry-bulb temperature to 66°C at a rate of 1°C / h, and extend the steady-temperature baking time until all the tobacco stems are dry.

[0048] Comparative Example 4: Conventional Baking Process

[0049] The conventional baking process for upper tobacco leaves is as follows:

[0050] S1 Yellowing stage: After loading tobacco, burn a small fire to raise the temperature of the curing room to 35-36℃, maintain the wet-bulb temperature at 34-35℃, and keep the temperature steady for 6-8h until the tobacco leaves become hot and sweaty; then, raise the dry-bulb temperature to 38℃ at 1℃ / h, control the wet-bulb temperature at 36-37℃, keep the temperature steady for 25-30h, and the tobacco leaves will reach 70% yellow; then, raise the dry-bulb temperature to 40℃ at 1℃ / 2h, and the wet-bulb temperature at 36-37℃, keep the temperature steady for 6-10h, remove moisture and control water in advance, and the tobacco leaves will become soft; then, raise the dry-bulb temperature to 42℃, and the wet-bulb temperature at 36-37℃, keep the temperature steady for 12-16h, and the tobacco leaves will reach yellow leaves and blue veins (90% yellow), and the main veins will become soft;

[0051] S2 color fixing period: the dry bulb temperature is raised to 45℃ at 1℃ / 2h, the wet bulb temperature is 36-37℃, and the temperature is kept stable for 6-10h. The ear turns yellow, the branch veins turn white, the leaf tips and edges are dry, the leaves wither, and the main veins are fully softened; then, the dry bulb temperature is raised to 48℃ at 1℃ / 2h, the wet bulb temperature is 37-38℃, and the temperature is kept stable for 6-12h. The main veins turn green and reach the small roll; then, the dry bulb temperature is raised to 51℃ at 1℃ / 2h, the wet bulb temperature is 38℃, and the temperature is kept stable for 6-8h. The main veins turn yellow and the leaves are half dry; then, the dry bulb temperature is raised to 54℃ at 1℃ / 2h, the wet bulb temperature is 39℃, and the temperature is kept stable for 14-20h. The main veins are completely yellow, the color difference between the front and back of the tobacco leaves is reduced, the leaves are dry, and the large roll is reached;

[0052] S3 Drying period: Raise the dry-bulb temperature to 60℃ and the wet-bulb temperature to 40℃ at a heating rate of 1℃ / h, and keep it steady for 6 to 8 hours. The main veins turn purple and shrink. Afterwards, raise the dry-bulb temperature to 68℃ and the wet-bulb temperature to 41℃ at a heating rate of 1℃ / h, and keep it steady for 25 to 30 hours, until the smoke veins are completely dry.

[0053] The experiment was conducted at the Fuquan Base in Qiannan Prefecture, Guizhou Province from 2023 to 2024. The test flue-cured tobacco variety was Yunyan 87, and the 15th to 16th leaf position tobacco leaves of the upper leaves were used as test materials. The test curing room was a standard intensive curing room. The test tobacco leaves were cultivated and managed in accordance with the standardized local high-quality tobacco production, and were harvested and cured according to the tobacco leaf maturity standards and baking process. The 15th to 16th leaf position tobacco leaves of the upper part that were not sprayed with foliar nutrient regulators before harvesting and baking were baked according to the conventional baking process (local ten key stable temperature point baking process, reference example 4) as control 1. The 15th to 16th leaf position tobacco leaves obtained after the first two sprayings of the present invention were used as test materials, and were baked according to the conventional baking process (local ten key stable temperature point baking process, reference example 4) as control 2, and the baking process of the present invention (Example 2) was used as treatment.

[0054] The harvested fresh tobacco leaves are put into a standard intensive curing room for curing. The following is an explanation of the influence on the grade structure, economic characteristics, chemical composition coordination, aroma component content and sensory quality of the upper tobacco leaves after curing. The results show that the method (treatment) of the present invention is significantly better than the conventional production control 1 and the conventional curing control 2.

[0055] 1. Effects of different treatments on grade structure and economic traits of flue-cured tobacco leaves

[0056] Table 3 Effects of different treatments on grade and economic traits of flue-cured tobacco leaves

[0057]

[0058]

[0059] 2. Effects of different treatments on the chemical composition of flue-cured tobacco leaves

[0060] Table 4 Effects of different treatments on the chemical composition content and harmony of flue-cured tobacco leaves

[0061]

[0062] Note: The ratio of reducing sugar to total sugar is more harmonious when it is greater than 0.9.

[0063] 3. Effects of different treatments on the aroma content of flue-cured tobacco leaves

[0064] Table 5 Effects of different treatments on the aroma components of flue-cured tobacco leaves (μg / g)

[0065]

[0066] 4. Effects of different treatments on sensory quality of flue-cured tobacco leaves

[0067] Table 6 Effects of different treatments on sensory quality of flue-cured tobacco leaves

[0068]

[0069] Note: The sensory quality evaluation is the sum of the scores of aroma quality, aroma quantity, taste, offal, irritation and strength, each of which is 10 points.

[0070] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method based on nutritional regulation and matching baking of upper leaves of flue-cured tobacco, characterized in that: include: S1 One-time spraying: Spray leaf conditioner 1 on the 3rd to 5th day after the middle tobacco leaves mature and are harvested; S2 Secondary spraying: 1-2 days before the upper tobacco leaves mature and are harvested, spray the leaf regulator II; S3 Bake.

2. The method according to claim 1, characterized in that: The foliar regulator is composed of 3.0% to 5.0% glucose, 80 to 150 μmol / L melatonin and 0.6% to 1.0% α-aminoisobutyric acid solution, and the spraying amount is 10 to 20 kg per mu.

3. The method according to claim 1, characterized in that: The foliar regulator II is composed of 3.0% to 5.0% glucose and 80 to 150 μmol / L melatonin solution, and the spraying amount per mu is 10 to 20 kg.

4. The method for regulating the nutrition of the upper leaves of flue-cured tobacco and baking the upper leaves according to claim 1, characterized in that: The baking process is as follows: S3-1, yellowing stage: after ignition, the dry bulb temperature is raised to 32~34℃ and the wet bulb temperature is 32~33℃ at a rate of 1℃ / h, and the tobacco leaves are baked at a steady temperature until they turn 10% to 20% yellow; then, the dry bulb temperature is raised to 35~36℃ and the wet bulb temperature is 34~35℃ at a rate of 1℃ / h, and the tobacco leaves are baked at a steady temperature until they turn 20% to 30% yellow; then, the dry bulb temperature is raised to 39~40℃ and the wet bulb temperature is raised to 37~39℃ at a rate of 1℃ / h, and the baking time is extended by 6~10h, and the tobacco leaves are baked at a steady temperature until they turn 80% to 90% yellow and become soft; then, the dry bulb temperature is raised to 42℃ and the wet bulb temperature is 35~37℃ at a rate of 1℃ / 2~3h, and the tobacco leaves are baked at a steady temperature for 10~15h, until the leaves turn yellow and blue, and fully wither and become soft; S3-2, color fixing period: increase the dry bulb temperature to 44℃ at a rate of 1℃ / 3~4h, reduce the wet bulb temperature to 35~36℃, and bake at a steady temperature for 6~10h until the main tendons of the tobacco leaf tips turn yellow and the tobacco leaf tips curl; extend the baking time at 46~54℃ for 6~10h to promote the transformation of tobacco leaf internal substances and the generation of aroma substances, increase the dry bulb temperature to 46~47℃ at a rate of 1℃ / 2~3h, the wet bulb temperature is 36~37℃, and bake at a steady temperature 5~6h, until more than 2 / 3 of the tobacco leaves turn yellow and more than 1 / 2 of the leaves shrink and dry; then, raise the dry-bulb temperature to 49~51℃ at a rate of 1℃ / 2h, and the wet-bulb temperature to 37~38℃, and bake at a steady temperature for 6~10h until the tobacco leaves turn yellow and more than 2 / 3 of the leaves are dry; then, raise the dry-bulb temperature to 54℃ at a rate of 1℃ / 2h, and the wet-bulb temperature to 38~39℃, and bake at a steady temperature until more than 1 / 3 of the tobacco leaves shrink and the leaves are dry; S3-3, tobacco stem drying stage: raise the dry-bulb temperature to 56~60℃ at a rate of 1℃ / 2~3h, extend the steady-temperature baking time to 8~12h, control the wet-bulb temperature at 39~40℃, and bake at a steady temperature until more than 1 / 2 of the tobacco stems are dry; thereafter, control the wet-bulb temperature unchanged, raise the dry-bulb temperature to 65~66℃ at a rate of 1℃ / h, and extend the steady-temperature baking time until all the tobacco stems are dry.

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