WO2006038558A1

WO2006038558A1 - Method of drying barley tobacco leaves and barley tobacco leaves dried thereby

Info

Publication number: WO2006038558A1
Application number: PCT/JP2005/018136
Authority: WO
Inventors: Kazuharu Koga; Hitoshi Saito; Seiya Fujii
Original assignee: Japan Tobacco Inc.
Priority date: 2004-10-01
Filing date: 2005-09-30
Publication date: 2006-04-13

Abstract

A method of drying Barley tobacco leaves which comprises continuously drying yellowed tobacco leaves at 45°C to 55°C with the use of hot wind force to thereby inhibit the formation of nitrosamine, which is characteristic to tobacco, in the course of drying tobacco leaves.

Description

Specification

Method for drying burley leaf tobacco and burley dried by the drying method

Technical field

TECHNICAL FIELD [0001] The present invention relates to a method for drying leaf tobacco, and relates to a drying method that suppresses the production of nitrosamine peculiar to tobacco, which is said to be generated during leaf tapaco drying without impairing the original flavor of the type. More specifically, the present invention suppresses the production of nitrosamine peculiar to tobacco without drying the leaf tobacco's original flavor in the drying of a type of leaf tobacco, and the leaf tobacco in the process of drying after completion of yellowing and before the end of drying. The present invention relates to a method for drying and a kind of burley leaf tobacco dried by the drying method.

Background art

[0002] Leaf tobacco, which is the main raw material of cigarettes, is a yellow type and a type of burre. These leaf tabos are dried after harvest. The drying of leaf tobacco is roughly divided into the process of changing the content components contained in leaf tobacco in parallel with the dehydration and the subsequent dehydration process. Is done. The process of changing the content component is called washing, and the subsequent dehydration process is called drying (“Leaf Tobacco Cultivation Method” edited by Japan Leaf Tobacco Technology Development Association, published by Japan Tobacco Inc. (1991)).

[0003] As shown below, the drying methods of the yellow and barre types are fundamentally different.

[0004] Drying of yellow tobacco leaves consists of a yellowing period, a fixed color period, and a dry period of middle bone.

[0005] In the yellowing period, the leaves were heated for the purpose of yellowing and changes in the content components, while dehydration was being carried out.

It is easy to yellow.

[0006] In the color-fixing period, dehydration and yellowing leaf color fixation that match yellowing progress are performed for the purpose of changing the content components, complete yellowing, and fixing the leaf color.

[0007] In the dry period of the middle bone, the bone is dehydrated and dried for the purpose of drying and drying the middle bone.

[0008] Yellow flue-cured tobacco is dried using a dryer utilizing wind power, such as a Balta dryer. Drying time varies depending on the position and leaf condition. Between.

[0009] Drying of burley leaf tobacco is performed through a yellowing period, a browning period, and a middle bone drying period.

[0010] In the yellowing period, the process from hanging to completion of yellowing (the tip of the leaf begins to turn brown). The dry period of the middle bone refers to the period from the completion of browning to the complete drying of the middle bone.

[0011] Unlike the yellow variety, the drying of a kind of bale is performed under natural conditions. Facilities used include pipe houses, wooden drying rooms, and simple built drying rooms.

[0012] The drying of a kind of burre depends on natural conditions, and it is preferable to immediately control the temperature condition at around 30 ° C and the humidity condition at 70 to 80%. The time required for drying varies depending on the state of the leaf and the leaves, but in the case of continuous drying, it is approximately 20 to 35 days. The yellowing period is 3-5 days, the browning period is 4-6 days, and the dry bone period is 15-25 days.

[0013] Recently, research on hibacco has been introduced using a drying room (machine) that uses wind-fired power called so-called compact drying in order to facilitate the temperature and humidity control of a type of leaf tobacco. 84, 63-69 (1980), “Leaf tobacco research”, 122, 34-40 (1993), “Leaf tobacco research”, 125, 11-: 19 (1994)). The entire drying process is not performed using a compact drying chamber, but a period of drying is performed using a compact drying chamber.

[0014] By the way, in dry tobacco, N, 1 nitrosonornicotine (NNN), 4-(—'- nitromethylamino) -4- (3-pyridyl) 1 1-butanone (ΝΝΚ), Ν, 1 Nitrosoanatabine (NAT), Tobacco Specific Nitrosamine (hereinafter referred to as “TSNA”), which is represented by N′-nitrosoanabasin (NAB), is included. These TSNA are substances harmful to the human body. Known as.

[0015] TSNA is rarely contained in fresh leaves immediately after harvest, but after the start of drying, nitrate is reduced to nitrite by nitrite-reducing bacteria on the leaf surface, and this nitrite reacts with alkaloids contained in the leaf. If it is generated, it will be received and reduced.

[0016] In order to reduce the content of TSNA in dry leaf tobacco, JP 2001-503247 and JP 2002-503965 disclose that microwaves and acceleration are applied to leaf tobacco in the yellowing period during drying. Irradiating a particle beam is disclosed. This method is TSNA The leaf tobacco, which is less yellowing, is rapidly dehydrated and the drying is terminated, so that the above-mentioned curing cannot be performed sufficiently, and the original quality of the leaf tobacco such as flavor may be impaired. There is.

[0017] International publication WO00 / 15056 discloses that tobacco, which is in a yellowing period, is reduced in humidity, speed of temperature change, temperature, air flow, C0 level, in order to reduce TSNA in dried tobacco. It is disclosed to provide a controlled environment provided by controlling at least one of CO level, O level, etc. International Publication WO00Z15056 discloses that leaf tobacco in the yellowing period is dried (dehydrated) at high temperature and high air volume.

[0018] Japanese Patent Application Laid-Open No. 2004-73152 discloses a method of drying burley leaf tobacco after the start of browning under environmental conditions controlled to a temperature of 25 to 35 ° C and a humidity of 65 to 85%. It is described that the browning period is completed and then natural drying is performed.

[0019] As described above, various methods have been proposed for the purpose of suppressing the production of TSNA produced during the drying of tobacco, and the development of a drying method for further reducing the TSNA content is being pursued. .

Disclosure of the invention

[0020] After the completion of yellowing, the present invention suppresses the production of nitrous acid and the production of TSNA, which is a harmful substance produced by the reaction of the produced nitrous acid and alkaloids, while maintaining the quality of tobacco. It is an object of the present invention to provide a method for drying burley leaf tobacco in consideration of the drying conditions of the above, and a burley leaf tobacco dried by the drying method.

[0021] As described above, drying of leaf type leaf tobacco is performed in a pipe house, a wooden drying room, etc., and the drying itself is different from yellow varieties, and depends on external conditions, particularly the weather conditions of the year. fluctuate. When high-humidity conditions are encountered, it has been found that TSNA production increases due to increased production of nitrite nitrogen with the increase of nitrate-reducing bacteria on the leaf surface. In particular, we found an increase in TSNA content during the dry period of the intermediate bone, where the dry period is long.

[0022] As a result of intensive research on a method for drying leaf tobacco that suppresses the production of TSNA in leaf tobacco produced during drying, the present inventors have harvested leaf tapaco after completion of yellowing that has been harvested and subjected to drying. By drying under constant and controlled temperature conditions using wind power, It was found that TSNA production can be suppressed while maintaining the quality of the tobacco. The present invention is based on such knowledge.

[0023] That is, the present invention is a method for drying a burley leaf tobacco, and after the yellowing is completed, the leaf tobacco is continuously used at a temperature condition of 45 ° C to 55 ° C using wind power. It provides a method for drying burley leaf tobacco, which includes drying and thereby inhibiting the production of TSNA produced during leaf tobacco drying.

[0024] The present invention also provides a burley leaf tobacco dried by a powerful drying method.

[0025] In the present invention, in the drying using the wind power, it is possible to further suppress the generation of TSNA by drying at a wind speed of 20 to 45 cm / sec, preferably 35 to 45 cm / sec.

[0026] Further, in the drying using wind power, the air in the drying chamber can be exhausted continuously or intermittently. Thereby, drying can be promoted by discharging high-humidity air in the drying chamber. In that case, the force S can be achieved by placing the damper provided in the drying chamber in an open state (continuous exhaust) or by automatically opening and closing the damper (intermittent exhaust).

[0027] It should be noted that drying using wind-fired power may be performed by heating equipment and air blowing equipment. For example, drying using a Balta dryer with yellow seed drying, a compact drying chamber with one barre, and the like can be mentioned. In addition, it includes drying in a pipe house for drying burre and drying in a heated air blower used in a wooden drying room.

BEST MODE FOR CARRYING OUT THE INVENTION

[0028] As described above, in the yellowing period, which is the early stage of drying, the TSNA content in the leaf tobacco is low, but as drying progresses, nitrite is formed by the action of nitrate reducing bacteria present on the leaf surface. TSNA is produced by the reaction between the produced nitrous acid and the alkaloids present in the leaves. The present inventors have confirmed that the production conditions of TSNA produced after the browning period are influenced by the production of TSNA, particularly by temperature conditions.

[0029] Therefore, in the present invention, yellowing of the burley leaf tobacco subjected to drying is completed (end of yellowing period). After that, the leaf tobacco is subjected to a temperature condition of 45 ° C to 55 ° C using wind power. Continuously dried It is something to make. If this temperature is less than 45 ° C, the TSNA content will increase because it takes time to dry. It was also found that when this temperature exceeds 55 ° C, the drying time is shortened and the force nitrosation reaction is accelerated, so that the TSNA content increases.

[0030] In drying using wind power, air having the above temperature is blown and circulated in the drying chamber, and the wind speed at this time is set to 20 to 45 cm / second, more preferably 35 to 45 cmZ second. By promoting dehydration, the drying period is shortened and the production of TSNA is suppressed. When the wind speed is less than 20 cm / sec, drying does not proceed and it takes a drying period, so TSNA tends to be generated and accumulated. On the other hand, when the wind speed exceeds 45 cm / sec, the tobacco leaves are dehydrated rapidly, and there is a tendency for quality and flavor to decline.

[0031] In the drying of tobacco in the present invention, exhausting the inside of the drying chamber is effective for promoting drying. Since dehydration is not promoted in a high humidity state, it is a preferable mode to exhaust the dehydrated water from the leaf tanks to the outside by exhaust.

[0032] In the present invention, the time when the burley leaf tobacco is subjected to the drying conditions of the present invention is after the completion of yellowing and until the middle bone drying period. In leaf tobacco before completion of yellowing, the above-mentioned curing is not sufficiently performed, so that it is not possible to obtain dry leaves of good quality. In addition, the dry period of the intermediate bone is preferably until the intermediate period of dry bone because the dry period can be shortened by performing dry bone in the drying conditions of the present invention. By shortening the drying period, production and accumulation of TSNA is suppressed. If it is later in the middle bone dry, the number of days is short, so the effect is not expected much.

[0033] Therefore, in the present invention, after the yellowing of the burley leaf tobacco, the period from the completion of yellowing to the middle stage of dry bone, for example, immediately after completion of yellowing, during browning, immediately after completion of browning, or intermediate dry bone In the state which exists in this, it can use for the drying conditions of this invention.

[0034] The number of days required for drying according to the drying conditions of the present invention varies depending on the state of the tobacco, the timing of drying, and the drying conditions such as the temperature 'wind speed. When drying using a Balta dryer with a wind speed of 40 cm / sec and a damper open (continuous exhaust in the drying chamber), it is possible to finish drying yellowed tobacco in 3 to 3.5 days. .

[0035] Until the burley leaf tobacco of the present invention is subjected to the drying conditions of the present invention, conventional drying conditions are used. It may be dried in a matter. For the drying, a pipe house, a wooden drying room and a compact drying room can be used.

[0036] Drying using wind power used in the present invention has heating equipment and air blowing equipment as described above, and is known per se. For example, a circulating Balta dryer used for drying yellow tobacco can be used, and a non-compartment drying chamber used for drying Burre. For example, a circulating Balta dryer is described on pages 164 to 165 of the “Leaf tobacco cultivation method”. Basically, in the circulation Balta dryer, a drying chamber is provided in which a leaf tobacco is suspended in, for example, two upper and lower stages in a substantially hermetically sealed room. The bottom surface of the drying chamber is composed of a perforated plate so that air can freely flow in and out of the drying chamber. An upper air passage and a lower air passage for sending and discharging circulating air are provided at the upper and lower portions of the drying chamber. A circulation duct communicating with the upper air flow path and the lower air flow path is provided at the side of the drying chamber. An air blower is provided in the circulation duct, and the air sent also by the air blower is heated by a burner through a heat exchanger. In addition, an intake / exhaust damper is provided above the circulation duct to take in external air and discharge the same amount of drying room air. A dry bulb thermometer and a wet bulb thermometer are installed in the drying chamber. The thermometer, damper, and burner are connected to the control unit, and are controlled under conditions set according to the temperature and humidity in the drying chamber. The control of the burner drive and the humidity inside the drying chamber are controlled by exhausting the high humidity air inside by opening and closing the damper and taking in the low humidity air from outside. The compact drying room has the same equipment as the Balta dryer, and the same control is performed.

[0037] In the present invention, drying under a constant humidity condition, for example, control by opening / closing a damper (intermittent exhaust) by automatic control at a dry bulb temperature of 50 ° C and a wet bulb temperature of 40 ° C is compared to the conventional method. TSNA generation can be suppressed by promoting drying, but drying can be promoted by performing drying while the damper is open and always exhausting part of the air in the drying chamber (continuous exhaust). TSNA generation can be suppressed.

[0038] Hereinafter, the present invention will be described with reference to several examples, but the present invention is not limited to these examples.

[0039] Example 1: Drying of Burre and generation of TSNA under yellow seed drying conditions In this example, Burare 1 leaf tobacco Kitakami 1 (main leaf) was used for the experiment.

[0040] That is, the harvested leaves were dried with a Balta drier using the drying conditions of yellow seeds. To dry the leaf tapaco, a circulating Balta dryer (floor area 0.75 m ² ) manufactured by Kihara was used. About 30 pieces of harvested leaves were knitted on steel nongers and hung in a dryer. Drying conditions were yellowing at a dry bulb temperature of 36-43 ° C (60 hours), lamina was dried at 45-55 ° C (33 hours), and then the bone was dried at 68 ° C (27 hours) ) After completion of drying, the sampled leaf octopus was separated into lamina (meat) and middle bone. The separated lamina was freeze-dried and then pulverized as an analytical sample. A pipe house in which a vinyl and a mouse are stretched over a steel framework, which is a kind of burre, is dried. The dry leaves dried in () were used as controls.

[0041] Weigh 5 g of analytical sample into a 200 mL Erlenmeyer flask, add 0 · 01 M NaOH solution (contains Thimer osallOO / ig / mL), remove lOOmL, place on a shaker, and extract at room temperature for 2 hours. Went. Then, the extract was filtered using filter paper (No. 5C manufactured by ADVANTEC).

[0042] Next, NNN, NNK :, NAT and NAB in the extraction night were quantified by gas chromatography according to the Spiegelhalder method (Spiegelhalder Β ·, Kubacki S. and Fischer S. (198 9) Beitr. Tabakforsch. Int ., 14 (3), 135-143, Fischer S. and Spiegelhalder B. (1989) Beitr. Tabakforsch. Int., 14 (3), 145-153).

[0043] That is, first, the filtrate lOmL was added to a column filled with kieselguhr (particle size 60-: 160 mm, MERCK) and ascorbic acid. TSNA was dissolved and flowed down using dichloromethane. This falling liquid was concentrated to dryness and then redissolved in dichloromethane to obtain a sample for gas chromatography. The obtained sample was analyzed using gas chromatography HP6890 (Hewlett Packard) equipped with column DB-17 (J & W, length 30 m, diameter 0.53 mm) and detector TEA_ 543 (Thermedics). did. The results are shown below.

[table 1] Content SN TA CM

O C

Completed browning

CO

Dry final dry color fire (Wind dry season completion:

End of regular period)

Dry bar «Firepower

乾 Dry-dried hard-to-dry,

o ∞ 6

\ o

Use)

¾

00 (D

卜 CO

m 6 d

d 6

As is clear from these results, the TSNA content in wind-dried dry leaf lamina is higher than the TSNA content in dry leaf dried with standard pino. Therefore, it was confirmed that TSNA could not be reduced at all even if the drying conditions of yellow flue-cured tobacco were applied to the drying of burley flora. [0045] In addition, the TSNA content in the lamina after drying using wind-fired power was low at the completion of browning corresponding to the end of the yellow color fixation period, but increased rapidly at the end of drying. This is presumably due to drying at a high temperature during the dry period of the bone. It is presumed that the nitrosation reaction by accumulated nitrous acid and alkaloids in leaves was promoted by encountering high temperatures.

[0046] Example 2: Drying temperature and TSNA generation of leaf tobacco that has been yellowed and browned in a standard pipe house (conventional drying)

In this example, burley 21 (genuine leaf), a kind of burley leaf tobacco, was used for the experiment.

[0047] That is, the harvested leaves were dried in a standard pipe house that was conventionally dried until yellowing was completed (5 days after harvesting) and browning was completed (10 days after harvesting). 25 pieces of leaf tobacco in the middle of drying were knitted on steel hangers, suspended in the Balta dryer used in Example 1, and dried at the dry bulb temperature of 40, 50, 60 and 70 ° C until the drying was completed. Table 2 shows the number of days required for drying. After drying, the sampled tobacco was separated into lamina and middle bone. The separated lamina was freeze-dried and then powdered to obtain a sample for analysis. TSNA was analyzed as in Example 1. The results are also shown in Table 2 below.

[Table 2]

As shown in Table 2, the TSNA content at the completion of yellowing and browning before hanging in the Balta dryer is 0.19 and 0.21 ig / g, respectively. Sphere TSNA content in dry leaf lamina dried at 50 ° C is lower than that dried at 40, 60 and 70 ° C. And the longest drying time by wind power at 40 ° C 60 and the shortest drying time by wind power at 70 ° C. The reason for the increase in TSNA content at drying temperatures of 60 and 70 ° C is that nitrosation reaction was promoted by drying at high temperature, and TSNA content was increased. The most significant increase in TSNA content at 40 ° C is thought to be due to the increase in TSNA content due to the time required for bone drying in the latter half of the drying period, when TSNA is easily formed. [0049] Example 3: Wind speed and damper conditions and suppression of TSNA generation in wind-powered drying

In the present example, Kitakami No. 1 (going leaves, true leaves) of burley leaf tobacco was used for the experiment.

[0050] That is, the harvested leaves were dried with a pipe house and wind-fired dryer. The Balta dryer shown in Example 1 was used as a wind-fired dryer. Table 3 shows the dry test areas. For districts 3 and 6, drying is performed at a dry bulb temperature of 35 to 37 ° C and wet bulb temperature of 33 to 34 ° C until yellowing is completed, and drying by wind power is set to a dry bulb temperature of 50 ° C. did. In the 5th and 8th districts, drying was performed at a dry bulb temperature of 35 to 39 ° C and a wet bulb temperature of 32 to 34 ° C until the browning was completed, and drying by wind power was performed at a dry bulb temperature of 50 ° C. . In the 4th and 7th districts, they were dried in a standard pipe house until yellowing was completed, and then suspended in a Balta dryer. In 6-8, the damper was opened after the dry bulb temperature rose to 50 ° C. In the 3rd to 5th districts, the dry bulb temperature was set to 50 ° C and the wet bulb temperature was set to 40 ° C, and the damper was opened and closed by automatic control. The 1st and 2nd districts were dried in a pipe house until the drying was completed. As the 1st district, a standard pipe house (with cold and cold) was used, and as the 2nd district, a high-humidity pipe house intended to promote the generation of TSNA was used. After drying, the sampled tobacco was separated into laminae and midbones. The separated lamina was freeze-dried and then pulverized as a sample for analysis. A high-humidity pipe house is a pipe house covered with silver aluminum sheet to make the room highly humid in a pipe house covered with vinyl (the same shall apply hereinafter).

[0051] TSNA extraction quantification was performed in the same manner as in Example 1.

[0052] In addition, nitrite nitrogen in dry leaves was analyzed by the method of Clutchfield and Burton (Crutchfield JD and Burton HR, Anal. Lett., (22) 555-571 (1989)). In other words, 0.5 g of mesophyll samples from each section were applied to a 50 mL centrifuge tube, and 25 mL of the extract (KCllOg / Littonore, Snorefaninoremid 5 g / Lit Nore, Triton X—100 lmL / Lit Nore) was calorie-free at room temperature. Nitrite nitrogen was extracted by shaking for 30 minutes. These extracts were filtered using filter paper (ADVA NTEC, No. 1), 10 mL of the filtrate was collected in another centrifuge tube, 0.5 g of activated carbon was added, and the mixture was shaken at room temperature for 15 minutes. Furthermore, it filtered using the filter paper (ADVANTEC, No. 5C), and removed activated carbon. The obtained filtrate was used as a sample for nitrite nitrogen determination.

[0053] Autoanalyzer (BRAN + LUEBB) was used to determine the nitrite nitrogen content in the extract. Using E company, AACSII), the nitrite nitrogen content was converted from the absorbance at 550 nm. For the color development of I nitrate nitrogen, 1% snowefanolenoamide and 0.1% N-naphthinoreethylenediamine dihydrochloride were used.

Table 4 shows the analysis results of TSNA and nitrite nitrogen (N0-N).

2

[Table 3]

Table 3

Dry fee formula test ¾Λ, yellowing or (because of the cow until the completion of transformation and yellowing or cattle from the end of ΙάίΙ ^ to the end of drying

Ward No o. Drying time 鵷 Time required

Eve /, Us (until yellowing is completed) Eve House

1

8 8 hours 7 1 6 (total 8 0 4

High humidity pipe house (until yellowing is completed) High humidity pipe / us

2

1 1 2 hours 6 9 2 hours (total 8 0 4 hours)

/ Luk dry «(until yellowing is completed) Bulk dry

3 ¾¾ 3 5 ° C ¾¾3 3 ° C) for 2 2 hours, then ¾¾5 0 ° C (wet bulb 40 C), 20 cm / s, damper open / close ¾ * 3 7 ° C (j showing bulb 3 4 C) 3 6 hours 1 1 1 hour (total 1 6 9 hours)

Bulk freezer

/ Evehouse (until yellowing is completed)

4 ¾¾5 0 ° C (wet bulb 40 ° C), Hil2 0 _C m sec, damper open / close

8 8 hours

1 0 2 hours (Total Ί 90 hours)

Lek Inui «(until completion of change)

/ 《Zorek Dry ¾

¾¾3 at 5 ° C (; i¾3 3 ° C) for 22 hours, then

5 ¾¾5 0 ° C (wet bulb 40 ° C), Jli 20 _C m sec, damper automatic open / close ¾¾c3 7 ° C (wet bulb 3 4 ° C) 3 6 B # Fs

7 2 hours (total 2 0 2 separated)

¾¾3 7 2 separation at 9 ° C (wet bulb 3 2.C)

(Until the completion of the bulk drying process)

6 ¾¾3 2 ° C for 2 2 hours at 5 ° C (3 ° C for 3 ° C) and 5 0 for pickles. C, 5l4 0 _C msec, damper open (continuous)

¾¾3 7. C (wet bulb 3 4 ° C) 3 6 hours 7 7 hours (total 1 3 5 ^)

/ Luk dry ¾

»/ Yipno \ us (until yellowing is completed)

7: 50 ° Μ Α 0 cm / s, damper: open (continuous)

88 hours

7 1 hour (total 1 5 9 hours)

(Until bulk drying)

Nork dry

¾¾3 at 5 ° C (; S¾3 3 ° C) for 22 hours, then

8: 50 ° C, ®14 0 cm / s, damper: open (continuous weaving f gas) ¾¾3 7 ° C (wet bulb 34 ° C) for 3 6 hours, then

5 4 hours (total 1 8 4 hours)

¾¾3 7 2 hours at 9 ° C (wet bulb 3 2 ° C)

Table 4

Note) r― ”… No sampling ΓΝΤΙ… No

[0055] As can be seen from the results shown in Table 4, both the leaf and the main leaf were dried with a Balta dryer or dried by wind-fired power at 50 ° C after the completion of browning. TSNA content in lamina is lower than dry leaves dried in a pipe house. In addition, for both leaf and leaf, after the yellowing was completed in the pipe house, the TSNA content in the dry leaf lamina that was dried at 50 ° C with a Balta dryer was higher than that of the dry leaf dried in the pipe house. Low.

[0056] When drying by wind-fired power with a Balta dryer at a dry bulb temperature of 50 ° C, the TSNA content in the dry leaf lamina is dried at the pipe house, even when the wind speed is 20cmZs, the damper is automatic or the wind speed is 40cmZs, and the damper is open. Lower than dry leaf lamina. It can also be seen that dry leaves dried with a Balta dryer produced less nitrous acid than dry leaves dried in a pipe house.

[0057] It can also be seen that the drying method using the Balta dryer can drastically shorten the drying time as compared with the pipe house.

[0058] Example 4: Drying temperature and TSNA suppression in wind-powered drying

In this example, Burare 1 leaf tobacco Kitakami 1 (main leaf) was used for the experiment.

[0059] That is, leaf tobacco harvested in 2002 and 2003 was dried under the drying conditions shown in Table 5 and Table 6 below, respectively. The Balta dryer shown in Example 1 was used as the wind-fired dryer. After drying, the sampled tobacco was separated into laminae and midbones. The separated lamina was freeze-dried and then pulverized as an analytical sample, and quantitative analysis of TSNA and nitrite nitrogen was performed in the same manner as in Examples 1 and 3. The results are shown in Table 7 and Table 8.

[Table 5]

Table 5

Note) was conducted in 2002.

Table 6

Note) was conducted in 2003.

True leaf

Convergence When browning is complete When drying is completed

TSNA ^ i N0 ₂ — N content TSNA ^ m N0 ₂ — TSNA content N0 ₂ — N ^ fi

(fJt g / g) iu g / g) (jU g / g) (/ g / g) (u g / g) (g / g)

1-1 0. 17 1. 1 1 0. 44 1. 05 2. 26 1. 37

1 1 2 0. 17 1. 1 1 1. 21 2. 46 6. 10 1. 34

1 -3 0. 17 1. 1 1 ― ― 1.36 NT

1 -4 0. 17 1. 1 1 ― 0. 99 0. 78 Note) “One”: Sampling

ΓΝΤ ”... minute ίίΗ ず

[0060] As is apparent from the results shown in Table 7 and Table 8, TSNA content in dry leaf lamina dried at 45, 50, and 55 ° C dry bulbs by wind-fired power is The amount of nitrous acid produced in the dry leaves dried with the Balta dryer is less than the dry leaves dried in the pipe house.

[0061] Example 5: Inhibition of TSNA and nitrite nitrogen production in the midbones of wind-fired drying In this example, Burare 1 leaf tobacco Kitakami 1 (main leaf) was used for the experiment.

That is, the harvested leaves were dried under the drying conditions shown in Table 6 above. The Balta dryer shown in Example 1 was used as the wind-fired dryer. After drying, the sampled tobacco was separated into lamina and midbone. The separated middle bone was freeze-dried and then pulverized as an analytical sample, and TSNA and nitrite nitrogen were quantitatively analyzed in the same manner as in Examples 1 and 3. The results are shown in Table 9.

[Table 9]

[0063] As is apparent from the results shown in Table 9, both the STSNA and nitrite nitrogen production of the bones in the dry leaves in the Balta dryer were less than the dry leaves in the pipe house. Nare ,.

[0064] In any of the above examples, the leaf tobacco dried by the drying method of the present invention had the same flavor and quality as the leaf tobacco dried by the conventional method. As described above, according to the present invention, while maintaining the quality of tobacco, the production of nitrous acid and the production of TSN A, a harmful substance produced by the reaction of the produced nitrous acid and alkaloids, are suppressed. There is provided a method for drying burley leaf tobacco. The burley leaf tobacco dried by the drying method of the present invention has a low TSNA content.

Claims

The scope of the claims

A method for drying burley leaf tobacco, in which the leaf tobacco after yellowing is continuously dried using wind power, at a temperature of 45 ° C to 55 ° C. A method for drying burley leaf tobacco, which includes inhibiting the production of nitrosamines peculiar to the tobacco produced.

2. The method for drying burley leaf tobacco according to claim 1, wherein the drying is performed at a wind speed of 20 to 45 cm / sec.

2. The method for drying burley leaf tobacco according to claim 1, wherein the drying is performed under a wind speed condition of 35 to 45 cm / sec.

2. The method for drying Burley seed tobacco according to claim 1, wherein the drying is performed under continuous or intermittent exhaust in a drying chamber.

2. The method for drying burley leaf tobacco according to claim 1, wherein the leaf tobacco is subjected to drying under the above conditions from the completion of yellowing to the middle middle bone dry period.

A kind of burley leaf tobacco dried by the method according to claim 1.