CN105136947A - Method of accurately representing and evaluating fruit smell character in fragrance of tobacco - Google Patents

Abstract

The invention discloses a method of accurately representing and evaluating fruit smell characters in fragrance of tobacco. The method includes the steps of obtaining aroma substance quantitative data through HS-GC-MS/MS detection method, performing calculation through threshold value of relative aroma substances, and performing construction to obtain tobacco fruit fragrance note index G. The method is simple in operations, is not liable to be interfered by impurities and is accurate in detection result. The GC-MS/MS is higher than GC-MS in both selectivity and sensitivity, so that the method avoids the problems that GC-MS is low in sensitivity, is insufficient in resolution, is poor in selectivity and is liable to cause a pseudo-positive result and cannot shows sufficient qualitative/quantitative information. In the invention, on the basis of substance base, fruit smell character in fragrance of tobacco is described and expressed, so that subjectivity due to sensory evaluation is avoided and the fruit smell characters tobacco is comprehensively represented and evaluated objectively.

Description

A Method for Accurate Characterization and Evaluation of Fruity Flavor Characteristics in Cigarette Aroma

technical field

The invention belongs to the technical field of cigarette sensory quality evaluation and analysis, and in particular relates to a method capable of accurately characterizing and evaluating the fruity aroma feature in cigarette aroma.

Background technique

As a burning and smoking consumer product, the sensory quality of cigarettes is its core and soul, so the evaluation and analysis of cigarette sensory quality has always been one of the most important contents in cigarette technology work. The literature survey shows that in recent years, a large number of technical research and development have been carried out around the sensory quality of cigarettes, which can be summarized into two types: evaluation of cigarette sensory quality and analysis of substances related to sensory quality.

1. Evaluation of sensory quality of cigarettes

There are currently two methods for evaluating the sensory quality of cigarettes, one is the comprehensive evaluation of the sensory quality of cigarettes, and the other is the evaluation of the sensory style and quality characteristics of cigarettes.

Comprehensive evaluation method for the sensory quality of cigarettes: as stipulated in GB5606.4-2005 "Cigarette Part 4: Sensory Technical Requirements", six evaluation criteria for sensory evaluation, including gloss, aroma, harmony, miscellaneous gas, irritation and Aftertaste;

Cigarette sensory style characteristics and quality characteristics evaluation method: YC/T497-2014 "Cigarette Chinese Cigarette Style Sensory Evaluation Method" further subdivides the sensory aroma style of cigarettes into: fresh fragrance, fruity fragrance, spicy fragrance, woody fragrance, green fragrance, 15 aroma indicators such as flower aroma, herbal aroma, bean aroma, cocoa aroma, milk aroma, paste aroma, baking aroma, sweet aroma, flue-cured tobacco aroma and air-cured tobacco aroma;

The above two current evaluation methods are evaluation and analysis methods established based on the subjective experience of smokers such as vision, smell, and taste. Among them, GB5606.4-2005 is mainly used in the compliance inspection of the sensory quality of cigarette products, while YC/ T497-2014 is applied to the consistency test of the sensory quality of cigarette products. However, these two methods need to rely on the experience of the judges of the sensory quality of cigarettes, and are easily affected by various factors such as the professional level of the judges, smoking evaluation skills, subjective preferences, etc., and the evaluation results of different judges may vary greatly.

2. Analysis of substances related to the sensory quality of cigarettes

With the continuous improvement of detection technology, researchers have used headspace solid-phase microextraction-GC/MS, LC-MS, sensors, electronic nose, near-infrared and other technical means to detect the aroma-causing substances related to the sensory quality of cigarettes. The multivariate regression was carried out on the concentration of aroma-causing substances and their aroma-causing contributions, and the influence of different concentrations of substances on the sensory aroma of cigarettes was found by establishing corresponding regression equations. For example, CN201210388661 discloses a method for detecting and judging cigarette flavor type. Although the regression equation can explain the correlation between the concentration of aromatizing substances and cigarette aroma to a certain extent. However, the GC-MS method has problems such as low sensitivity, insufficient resolution, poor selectivity, easy to produce false positive results, and insufficient qualitative/quantitative information in the qualitative/quantitative aspects of substances, resulting in large gaps in qualitative/quantitative results. Uncertainty. At the same time, relevant research work cannot explain the significant effect of substances such as turkelenone and methyl isobutyrate that are low in content but have a large contribution to sensory aroma (ie, low threshold) on the fruity aroma style of cigarettes; lack of influence on cigarette quality characteristics And style features are based on the corresponding description and expression of the material basis, and many sensory evaluation characteristics cannot be explained from the material basis.

3. Summary

Existing evaluation and analysis methods have certain defects. How to accurately evaluate and analyze "cigarette style characteristics and quality characteristics" through chemical analysis techniques has become one of the major issues facing the scientific and technological workers in the tobacco industry. But there is not yet a good solution in the prior art.

Contents of the invention

The object of the present invention is to provide a method capable of accurately characterizing and evaluating the fruity aroma feature in cigarette aroma aiming at the deficiencies of the prior art. Quantitative data of aroma-inducing substances were obtained by headspace-gas chromatography-tandem mass spectrometry (HS-GC-MS/MS), and the fruity aroma index G of cigarettes was calculated and constructed through the threshold value of corresponding aroma-inducing substances. To avoid subjective errors caused by sensory evaluation and smoking.

The purpose of the present invention is achieved through the following technical solutions.

Unless otherwise specified, the percentages used in the present invention are all mass percentages.

A method for accurately characterizing and evaluating fruity aroma characteristics in cigarette aroma, comprising the following steps:

(1) Ethyl formate, amyl acetate, isobutyl acetate, ethyl isobutyrate, ethyl valerate, γ-undecalactone (peach aldehyde), dihydroactidolactone, isoamyl isovalerate Esters, damascenone, geranyl acetone, turkelenone and benzaldehyde as 12 characteristic substances that significantly affect the fruity aroma style of cigarettes;

(2) Establishment of standard working curves for characteristic substances:

①Standard stock solution: Accurately weigh 10.0mg of characteristic substance standard respectively, place them in the same 100mL volumetric flask, dissolve and dilute to volume with absolute ethanol, and prepare a mixed standard stock solution with a mass concentration of 100 μg/mL, Store in a refrigerator at 4°C for later use;

② The internal standard naphthalene was dissolved in absolute ethanol at a concentration of 100 μg/mL;

③Respectively pipette 0.1mL, 0.5mL, 1mL, 5mL and 10mL of the stock solution in ①, place them in five 100mL volumetric flasks respectively, add 1mL of internal standard solution, and dilute with absolute ethanol to obtain a concentration of 0.1μg/mL in sequence , 0.5 μg/mL, 1 μg/mL, 5 μg/mL, and 10 μg/mL compound solutions, in which the internal standard naphthalene concentration is 1 μg/mL, as the working standard solution for later use;

④ Perform linear regression with the response value ratio of 12 standard samples of characteristic substances and internal standard and their concentration ratio to obtain the standard working curve of each characteristic substance, the curve is forced to zero, and the linear correlation coefficient R2 must be greater ^than 0.999;

(3) Pretreatment of samples to be tested:

a. Take the shredded tobacco of the sample to be tested, and perform moisture determination according to "YC/T31 Tobacco and Tobacco Products Sample Preparation and Moisture Determination Oven Method";

b. Weigh 1.000g of shredded tobacco of the sample to be tested, put it in a 20mL headspace bottle, add 1mL of internal standard solution, quickly press the cap of the bottle, and shake to spread the shredded tobacco evenly and loosely on the bottom of the bottle;

(4) Instrumental analysis conditions for aroma-causing substances

①Headspace analysis conditions:

Headspace vial capacity: 20mL, sample loop capacity: 3mL, sample equilibration temperature: 100°C, sample loop temperature: 120°C, transfer line temperature: 160°C, sample equilibration time: 45min, GC cycle time: 70min, vial pressurization pressure : 138KPa, pressurization time: 0.20min, inflation time: 0.20min, sample loop equilibrium time: 0.05min, sample injection time: 0.50min;

② Chromatographic analysis conditions:

DB-5MS capillary column; inlet temperature: 250°C; constant flow mode, column flow rate: 1mL/min; split ratio: 20:1; heating program: initial temperature 50°C, hold for 2min, then increase temperature at a rate of 5°C/min to 200°C, keep for 10min, and finally raise the temperature to 250°C at a rate of 10°C/min, and keep for 20min;

③Mass spectrometry analysis conditions:

EI ionization mode, ionization energy 70ev; filament current: 80μA; ion source temperature: 170°C; transfer line temperature: 250°C; Q2 collision gas: argon purity 99.999%, CID gas pressure 1.5mtorr; scanning method: multiple reaction monitoring MRM mode, the detection time for each ion is 150ms;

The relevant qualitative ion pairs, quantitative ion pairs and optimized collision energy (CE) values are shown in Table 1:

Table 1:

(5) Read the response value of each characteristic substance in the shredded tobacco sample to be tested, and use the standard curve established in step (2) to correct the initial data of each characteristic substance in the sample to be tested, that is, to obtain a certain characteristic substance in the sample to be tested Content C _i :

$C_i=\frac{A_i{m}_{\mathrm{the\; s}}}{A_{\mathrm{the\; s}}{K}_i}\×\frac{1}{m\×(1-w)}$ …………… ①

Among them, C _i represents the content of a certain characteristic substance in the sample to be tested, and the unit is ug/g;

A _i is the peak area of a certain characteristic substance in the sample to be tested, and the unit is U (integral unit);

A _s is the peak area of the internal standard substance, and the unit is U (integral unit);

m _s is the amount of internal standard substance added, the unit is ug;

m is the mass of shredded tobacco, in g;

w is the moisture content of cut tobacco to be tested, in %;

K _i is the slope of the standard working curve of each characteristic substance;

(6) Calculation of Cigarette Fruity Flavor Index G:

The 12 characteristic substances contribute to the fruity aroma of cigarette smoke. The contribution of a certain characteristic substance to the fruity aroma of cigarettes is evaluated by the odor activity value OAV. The cigarette fruity aroma index model is the odor activity value of the 12 characteristic substances sum of:

Cigarette Fruity Aroma Index $G=\underset{i=1}{\overset{\mathrm{no}}{\Σ}}{f}_i\frac{c_i}{t_i}=\underset{i=1}{\overset{\mathrm{no}}{\Σ}}{f}_i{o}_i$ ………………②

In the formula: C _i is the content of i characteristic substances; t _i is the aroma threshold of i characteristic substances; O _i is the OAV value of i characteristic substances, namely n is the number of characteristic substances; because the fragrance threshold is very low, in order to facilitate the comparison with the sensory evaluation results, the OAV value of each characteristic substance is multiplied by a coefficient, and f _i is the correction coefficient of each substance, as shown in Table 2;

Table 2

characteristic substance Correction factor f _i ethyl formate 10 ² Amyl acetate 10 Isobutyl acetate 1 ethyl isobutyrate ^10-2 Ethyl valerate ^10-2 γ-undecalactone ^10-1 Dihydroactinolactone ^10-1 Isoamyl Isovalerate ^10-2 β-Damascone ^10-5 Geranylacetone ^10-2 Turkelenone ^10-6 Benzaldehyde ^10-1

(7) Judgment on the characteristics of cigarette fruity aroma style:

Judge the cigarette aroma according to the scoring criteria in Table 3;

Table 3 Criteria for Judging the Fruity Aroma Style of Cigarettes

The fruity aroma feature in the cigarette aroma is positively correlated with the cigarette fruity aroma index G, that is, the higher the cigarette fruity aroma index G value, the more significant the fruity aroma style of the cigarette.

Compared with the prior art, the present invention has the following advantages:

1. The present invention is guided by the characteristic index of cigarette style - fruity aroma, adopts HS-GC-MS/MS technical means, and on the basis of establishing the quality characteristic and style characteristic material spectrum library, the quality and style related substances of cigarettes are analyzed Qualitative and quantitative detection; use the test results to establish the mathematical expression of the fruity aroma index by using the statistical model, and the expression is comprehensively calculated with the corresponding threshold value to construct an index (fruity aroma index G) representing the style of cigarette fruity aroma, To comprehensively characterize and evaluate the fruity aroma style of cigarette products. The fruity aroma index G model is proposed to describe and express the fruity aroma characteristics of cigarettes from the perspective of material basis, explain many sensory evaluation characteristics from the material basis, and explain the characteristics of turkelenone, methyl isobutyrate, etc. Substances with low content but large contribution to sensory aroma (that is, low threshold) have a significant effect on the fruity aroma style of cigarettes. Moreover, the subjectivity of sensory evaluation and smoking is avoided, and the fruity aroma style of cigarette products is objectively and comprehensively characterized and evaluated.

2. Headspace-gas chromatography-tandem mass spectrometry (HS-GC-MS/MS) is easy to operate, less susceptible to impurity interference, and more accurate detection results. The selectivity and sensitivity of gas chromatography-tandem mass spectrometry (GC-MS/MS) are higher than those of gas chromatography-mass spectrometry (GC-MS), which avoids the low sensitivity, insufficient resolution, poor selectivity and false positive results of GC-MS. And can not give enough qualitative / quantitative information and other issues.

Detailed ways

In order to better understand the present invention, the present invention will be further described in detail through the following examples, but the examples are not intended to limit the technical solution of the present invention.

Example 1:

(1) Materials and instruments:

(1) Material: cigarette A of a certain brand;

Reagents: absolute ethanol (AR, Shanghai Reagent No. 1 Factory); ethyl formate, amyl acetate, isobutyl acetate, ethyl isobutyrate, ethyl valerate, γ-undecalactone (peach aldehyde), di Hydroactinolactone, isopentyl isovalerate, damascenone, geranylacetone, turkenone, benzaldehyde, naphthalene (purity greater than 98%, all purchased from Bailingwei).

(2) Instruments: AG204 electronic balance (sensitivity: 0.0001g, Swiss METTLERTOLEDO company); blast constant temperature drying oven (101A-2, Shanghai Experimental Instrument General Factory); headspace instrument (G1888, Agilent); GC-MS /MS (SCION456GC-TQ, Bruker Company); pipette gun (Tripette Company).

(2) Preparation of samples and determination of characteristic substances:

(1) Determination of 12 characteristic substances by HS-GC-MS/MS method

A. Sample preparation: Remove the filter tip from the finished cigarette A, peel off the tipping paper, and perform moisture determination according to "YC/T31 Tobacco and Tobacco Products Sample Preparation and Moisture Determination Oven Method";

Remove the filter tip from the finished cigarette A, peel off the tipping paper, weigh 1.000g of shredded tobacco (accurate to 0.1mg) into a 20mL headspace bottle with an analytical balance, add 1mL of internal standard solution, quickly press the bottle cap, and shake properly Spread the shredded tobacco evenly and loosely on the bottom of the bottle.

B. Static headspace conditions are: headspace bottle volume: 20mL, sample loop volume: 3mL, sample equilibration temperature: 100°C, sample loop temperature: 120°C, transfer line temperature: 160°C, sample equilibration time: 45min, GC cycle time : 70min, sample bottle pressurization pressure: 138KPa, pressurization time: 0.20min, inflation time: 0.20min, sample loop equilibrium time: 0.05min, sample injection time: 0.50min; can be adjusted appropriately according to the selected heating conditions GC cycle time;

C. When measuring by GC-MS/MS, the chromatographic conditions adopted are as follows:

a) Chromatographic column: DB-5MS elastic quartz capillary column (30m×0.25mm×0.25μm, Agilent, USA); or other equivalent chromatographic column, such as HP-5MS elastic quartz capillary column (30m×0.25mm×0.25 μm), MS (30m×0.25mm×0.25μm), etc.;

b) Injection port temperature: 250°C;

c) Temperature programming conditions: initial temperature of 50°C, keep for 2min, raise the temperature to 200°C at a rate of 5°C/min, keep for 10min, and finally raise the temperature to 250°C at a rate of 10°C/min, and keep for 20min; In specific cases, select other suitable temperature programming conditions;

d) Carrier gas: He (purity ≥ 99.99%); Q2 collision gas: argon (purity 99.999%).

e) Ionization method: EI source; ionization energy 70ev; filament current: 80μA; ion source temperature: 170°C; transmission line temperature: 250°C;

f) Scanning mode: multiple reaction monitoring MRM mode, CID gas pressure is 1.5mtorr; detection time for each ion is 150ms.

D. Calculation of measurement results: Measure a series of characteristic substance standard solutions by HS-GC-MS/MS method, use the ratio of the characteristic substance to the internal standard peak area as the vertical axis, and the ratio of the characteristic substance concentration to the internal standard concentration as the horizontal axis Coordinates, the calibration curves of the 12 characteristic substances were respectively established, and the curves were forced to zero. Perform linear regression on the calibration data, and the linear correlation coefficient R2 must be greater ^than 0.999.

Determine the sample, calculate the content of 12 characteristic substances according to the peak area in the sample, and calculate the content of one of the characteristic substances:

$C_i=\frac{A_i{m}_{\mathrm{the\; s}}}{A_{\mathrm{the\; s}}{K}_i}\×\frac{1}{m\×(1-w)}$ …………… ①

Among them, C _i represents the content of the characteristic substance obtained by detection and analysis, and the unit is ug/g;

A _i is the peak area of the characteristic substance in the sample, and the unit is U (integral unit);

A _s is the peak area of the internal standard substance, and the unit is U (integral unit);

m _s is the amount of internal standard substance added, the unit is ug;

m is the mass of shredded tobacco, in g;

w is the moisture content of cut tobacco to be tested, in %;

_ki is the slope of the working curve of each characteristic substance.

E. Measurement results:

(1) Cut tobacco sample A of a certain brand was prepared according to the method described, and the contents of 12 characteristic substances were determined by HS-GC-MS/MS method. The results are shown in Table 4:

Table 4 The results of HS-GC-MS/MS determination of 12 characteristic substances (ug/g) in A brand cigarettes

serial number name Content of target substance(ug/g) 1 ethyl formate 0.162 2 Amyl acetate 0.109 3 Isobutyl acetate 0.127 4 ethyl isobutyrate 0.035 5 Ethyl valerate 0.375 6 γ-undecalactone 2.192 7 Dihydroactinolactone 1.876 8 Isoamyl Isovalerate 0.249 9 β-Damascone 2.153 10 Geranylacetone 1.676 11 Turkelenone 5.094 12 Benzaldehyde 0.127

(2) Calculation of the fruity aroma index (G _A ) of brand A cigarettes:

Based on the above measurement results, the following formula is brought in:

Cigarette Fruity Aroma Index $G=\underset{i=1}{\overset{\mathrm{no}}{\Σ}}{f}_i\frac{c_i}{t_i}=\underset{i=1}{\overset{\mathrm{no}}{\Σ}}{f}_i{o}_i$ ………………②

In the formula: C _i is the content of i characteristic substances; t _i is the aroma threshold of i characteristic substances; O _i is the OAV value of i characteristic substances, namely n is the number of characteristic substances; in order to facilitate the comparison with the sensory evaluation results, the OAV value of each characteristic substance is multiplied by a coefficient, and f _i is the OAV correction coefficient of each substance. The odor activity values of the 12 characteristic substances are shown in Table 5.

Table 5 Odor activity values of 12 characteristic substances in shredded tobacco of brand cigarettes (O _i )

serial number name Aroma Threshold (ug/g) O _i f _i 1 ethyl formate 150 0.00108 10 ² 2 Amyl acetate 43 0.00253 10 3 Isobutyl acetate 3.4 0.0374 1 4 ethyl isobutyrate 5.7×10 ^-2 0.61 ^10-2 5 Ethyl valerate 2.7×10 ^-2 13.889 ^10-2 6 γ-undecalactone 0.95 2.307 ^10-1 7 Dihydroactinolactone 0.95 1.975 ^10-1 8 Isoamyl Isovalerate 9.3×10 ^-2 2.677 ^10-2 9 β-Damascone 9×10 ^-5 23922 ^10-5 10 Geranylacetone 5×10 ^-2 33.52 ^10-2 11 Turkelenone 2× ^10-6 2547000 ^10-6 12 Benzaldehyde 0.35 0.363 ^10-1

Fruity aroma index (G _A ) of brand A cigarettes = 3.93.

G _A indicates that the brand's cigarettes have a strong fruity aroma style.

Example 2:

Repeat the process of embodiment 1, select another brand cigarette B, measure its 12 kinds of characteristic substance contents with HS-GC-MS/MS method, measured value is as shown in table 6, and the odor activity value of 12 kinds of characteristic substances is as shown in table 7.

Table 6 The results of HS-GC-MS/MS determination of 12 characteristic substances (ug/g) in B brand cigarettes

serial number name Content of target substance(ug/g) 1 ethyl formate 0.167 2 Amyl acetate 0.095 3 Isobutyl acetate 0.126 4 ethyl isobutyrate 0.242 5 Ethyl valerate 0.625 6 γ-undecalactone 0.577 7 Dihydroactinolactone 1.838 8 Isoamyl Isovalerate 0.363 9 β-Damascone 1.841 10 Geranylacetone 1.694 11 Turkelenone 5.086 12 Benzaldehyde 0.157

Table 7 Odor activity values of 12 characteristic substances in shredded tobacco of B brand cigarettes (O _i )

Fruity fragrance index of brand B cigarettes (G _B )＝3.87

G _B indicates that the fruity aroma style of cigarettes of this brand is stronger, but weaker than that of A brand cigarettes.

Example 3:

Organize 14 technicians with the national cigarette sensory evaluation qualification certificate to test the aroma style indicators of A and B brands of cigarette samples (flue-cured tobacco aroma, air-dried tobacco aroma, fresh aroma, fruity aroma, spicy aroma, woody aroma, and green aroma) , flower fragrance, medicinal herb fragrance, etc.) to evaluate and obtain the fruity fragrance index evaluation score. The results are shown in Table 8.

Table 8 Fruity flavor index and sensory evaluation value of two brands of cigarettes A and B

brand Fruity Fragrance Index Fruity index sensory evaluation score A 3.93 4 B 3.87 4

As can be seen from Table 8, there is no significant difference between the fruity aroma index obtained in Examples 1-2 and the fruity index sensory evaluation score, which proves the accuracy of the method for characterizing and evaluating the fruity aroma characteristics in cigarette aroma proposed by the present invention. feasibility. Moreover, in the implementation process, the subjectivity of conventional sensory evaluation methods can be avoided, and the fruity aroma style of cigarettes can be characterized and judged more objectively.

Claims (1)

1. A method for accurately characterizing and evaluating fruity aroma characteristics in cigarette aroma, comprising the following steps: (1) Ethyl formate, amyl acetate, isobutyl acetate, ethyl isobutyrate, ethyl valerate, γ-undecalactone (peach aldehyde), dihydroactidolactone, isoamyl isovalerate Esters, damascenone, geranyl acetone, turkelenone and benzaldehyde as 12 characteristic substances that significantly affect the fruity aroma style of cigarettes; (2) Establishment of standard working curves for characteristic substances: ①Standard stock solution: Accurately weigh 10.0mg of characteristic substance standard respectively, place them in the same 100mL volumetric flask, dissolve and dilute to volume with absolute ethanol, and prepare a mixed standard stock solution with a mass concentration of 100 μg/mL, Store in a refrigerator at 4°C for later use; ③ The internal standard naphthalene was dissolved in absolute ethanol at a concentration of 100 μg/mL; ③Respectively pipette 0.1mL, 0.5mL, 1mL, 5mL and 10mL of the stock solution in ①, place them in five 100mL volumetric flasks respectively, add 1mL of internal standard solution, and dilute with absolute ethanol to obtain a concentration of 0.1μg/mL in sequence , 0.5 μg/mL, 1 μg/mL, 5 μg/mL, and 10 μg/mL compound solutions, in which the internal standard naphthalene concentration is 1 μg/mL, as the working standard solution for later use; ④ Perform linear regression with the response value ratio of 12 standard samples of characteristic substances and internal standard and their concentration ratio to obtain the standard working curve of each characteristic substance, the curve is forced to zero, and the linear correlation coefficient R2 must be greater ^than 0.999; (3) Pretreatment of samples to be tested: a. Take the shredded tobacco of the sample to be tested, and perform moisture determination according to "YC/T31 Tobacco and Tobacco Products Sample Preparation and Moisture Determination Oven Method"; b. Weigh 1.000g of shredded tobacco of the sample to be tested, put it in a 20mL headspace bottle, add 1mL of internal standard solution, quickly press the cap of the bottle, and shake to spread the shredded tobacco evenly and loosely on the bottom of the bottle; (4) The sample to be tested is analyzed and determined by the HS-GC-MS/MS method, and the instrument analysis conditions are as follows: ①Headspace analysis conditions: Headspace vial capacity: 20mL, sample loop capacity: 3mL, sample equilibration temperature: 100°C, sample loop temperature: 120°C, transfer line temperature: 160°C, sample equilibration time: 45min, GC cycle time: 70min, vial pressurization pressure : 138KPa, pressurization time: 0.20min, inflation time: 0.20min, sample loop equilibrium time: 0.05min, sample injection time: 0.50min; ② Chromatographic analysis conditions: DB-5MS capillary column; inlet temperature: 250°C; constant flow mode, column flow rate: 1mL/min; split ratio: 20:1; heating program: initial temperature 50°C, hold for 2min, then increase temperature at a rate of 5°C/min to 200°C, keep for 10min, and finally raise the temperature to 250°C at a rate of 10°C/min, and keep for 20min; ③Mass spectrometry analysis conditions: EI ionization mode, ionization energy 70ev; filament current: 80μA; ion source temperature: 170°C; transfer line temperature: 250°C; Q2 collision gas: argon purity 99.999%, CID gas pressure 1.5mtorr; scanning method: multiple reaction monitoring MRM mode, the detection time for each ion is 150ms; The relevant qualitative ion pairs, quantitative ion pairs and optimized collision energy (CE) values are shown in Table 1: Table 1: (5) Read the response value of each characteristic substance in the shredded tobacco sample to be tested, and use the standard curve established in step (2) to correct the initial data of each characteristic substance in the sample to be tested, that is, to obtain a certain characteristic substance in the sample to be tested Content C _i : $C_i=\frac{A_i{m}_{\mathrm{the\; s}}}{A_{\mathrm{the\; s}}{K}_i}\×\frac{1}{m\×(1-w)}$ …………… ① Among them, C _i represents the content of a certain characteristic substance in the sample to be tested, and the unit is ug/g; A _i is the peak area of a certain characteristic substance in the sample to be tested, and the unit is U (integral unit); A _s is the peak area of the internal standard substance, and the unit is U (integral unit); m _s is the amount of internal standard substance added, the unit is ug; m is the mass of shredded tobacco, in g; w is the moisture content of cut tobacco to be tested, in %; K _i is the slope of the standard working curve of each characteristic substance; (6) Calculation of Cigarette Fruity Flavor Index G: The 12 characteristic substances contribute to the fruity aroma of cigarette smoke. The contribution of a certain characteristic substance to the fruity aroma of cigarettes is evaluated by the odor activity value OAV. The cigarette fruity aroma index model is the odor activity value of the 12 characteristic substances sum of: Cigarette Fruity Aroma Index $G=\underset{i=1}{\overset{\mathrm{no}}{\Σ}}{f}_i\frac{c_i}{t_i}=\underset{i=1}{\overset{\mathrm{no}}{\Σ}}{f}_i{o}_i$ ………………③ In the formula: C _i is the content of i characteristic substances; t _i is the aroma threshold of i characteristic substances; O _i is the OAV value of i characteristic substances, namely n is the number of characteristic substances; because the fragrance threshold is very low, in order to facilitate and To compare the sensory evaluation results, multiply the OAV value of each characteristic substance by a coefficient, and _fi is the correction coefficient of each substance, as shown in Table 2; Table 2 characteristic substance Correction factor f _i ethyl formate 10 ² Amyl acetate 10 Isobutyl acetate 1 ethyl isobutyrate ^10-2 Ethyl valerate ^10-2 γ-undecalactone ^10-1 Dihydroactinolactone ^10-1 Isoamyl Isovalerate ^10-2 β-Damascone ^10-5 Geranylacetone ^10-2 Turkelenone ^10-6 Benzaldehyde ^10-1 (7) Judgment on the characteristics of cigarette fruity aroma style: Judge the cigarette aroma according to the scoring criteria in Table 3; Table 3 Criteria for Judging the Fruity Aroma Style of Cigarettes The fruity aroma feature in the cigarette aroma is positively correlated with the cigarette fruity aroma index G, that is, the higher the cigarette fruity aroma index G value, the more significant the fruity aroma style of the cigarette.