Fresh flower fragrance type Jinguanyin hydrolat as well as preparation method and identification method thereof

Abstract

The invention belongs to the technical field of natural product identification, and particularly relates to fresh flower fragrance type Jinguanyin hydrolat as well as a preparation method and an identification method thereof. The preparation method of the tea hydrolat comprises the following steps: S.1, sample pretreatment; and S.2, hydrolat extraction. The identification method of the tea hydrolat comprises the following steps: S.1, evaluating the overall aroma profile; s.2, separation and identification of aroma substances: separating the hydrolat sample A obtained in the step S.2 by using SPME, then identifying the substances by using Ma ssHunter workstation software-unknown substance analysis software, performing qualitative work on the aroma substances in the sample by using RI, GC-O and an aroma standard substance, and performing quantitative work on the aroma substances by using an internal standard method (ethyl caprate) and an external standard method; s.3, smelling fragrance; and S.4, performing aroma recombination and deletion. According to the technology provided by the invention, the Jinguanyin hydrolat can be prepared, aroma extraction is carried out through HS-SPME extraction, identification is carried out through a DB-5MS chromatographic column, meanwhile, aroma analysis technologies such as DFA, OMSE and the like are adopted, and the collection of key fresh flower fragrance components and the accuracy of identification results are guaranteed.

Description

Technical Field

[0001] This invention belongs to the field of natural product extraction and identification technology, and in particular relates to a light floral fragrance type of Guanyin hydrosol and its preparation and identification methods. Background Technology

[0002] Oolong tea is a typical semi-fermented tea with a rich floral and fruity aroma, making it popular among consumers. Tea aroma is a crucial factor influencing tea quality, directly impacting its market value while differentiating its flavor characteristics and grades. Jin Guanyin, a clonal oolong tea variety bred from Tie Guanyin and Huang Dan, possesses a strong floral and fruity aroma and has the potential to be developed into high-value tea-flavored products. With the continuous development of tea processing technology and the increasing demand for natural tea-flavored products, developing new tea-flavored products is extremely important.

[0003] In recent years, a new type of aromatic water product has emerged in the market, using characteristic aromatic parts of tea and other plants such as leaves, flowers, and fruits as raw materials. After aroma extraction, these products are developed into fragrant waters with realistic, rich, and clear aromas, commonly known as hydrosols or aromatic waters. Plant hydrosols have a wide range of uses, including food flavoring, beverage flavoring, and the development of daily chemical products and clinical pharmaceuticals. However, current technology for preparing tea hydrosols is still imperfect, related research is limited, the aroma components are not yet clearly defined, and there is a lack of effective methods for evaluating their aroma quality. Therefore, this invention aims to provide an extraction technology for Jin Guan Yin tea hydrosol, and simultaneously identify and analyze the active aroma components and key floral aroma components of Jin Guan Yin tea hydrosol.

[0004] Patent CN201610564959.7 provides a method for preparing tea hydrosol, using tea leaves as raw material and employing a process involving compound enzymatic hydrolysis, release, reduced-pressure steam distillation, cold trap recovery, low-temperature freezing concentration, centrifugal oil-water separation, and adsorption of trace moisture with anhydrous sodium sulfate. However, this patent only describes the preparation of tea hydrosol; the components of the prepared tea hydrosol remain unclear. The paper "Preparation Process and Aroma Component Analysis of Tea Flower Hydrosol" provides a chromatographic-mass spectrometry method, but using only this method is insufficient for accurately identifying the overall aroma profile and components of the tea hydrosol. Summary of the Invention

[0005] To overcome the problems of difficulty in identifying the components of tea hydrosol and low accuracy in existing technologies, this invention provides a method for preparing and identifying a light floral fragrance type of Jin Guan Yin hydrosol, which involves distilling and extracting tea hydrosol, evaluating the aroma profile of the hydrosol, using MassHunter workstation software to separate and identify aroma substances, and reconstructing and analyzing the aroma of the tea hydrosol.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0007] In a first aspect, the present invention provides a method for preparing a floral-scented Guanyin hydrosol, comprising the following steps:

[0008] S.1. Sample pretreatment: Mix the Jin Guanyin tea sample with purified water in a certain proportion and let it stand for a period of time;

[0009] S.2. Hydrosol Extraction: The tea sample obtained in step S.1 is placed in a rotary evaporator for extraction. The condensed hydrosol A of the light floral fragrance Jin Guanyin tea is collected by vacuum distillation.

[0010] Furthermore, in step S.1, the mass ratio of tea sample to purified water is 1:3.

[0011] Furthermore, the room temperature is 25℃±2℃.

[0012] Further, the rotary evaporation parameters in step S.2 are: rotation speed 45 RPM, rotary evaporation temperature 40-70℃, vacuum degree 30 mbar, condensation temperature -5℃, and rotary evaporation time 40-80 min.

[0013] Secondly, the above method can be used to prepare a fragrant Jin Guanyin tea hydrosol.

[0014] Thirdly, the present invention provides a method for identifying a floral-scented type of Guanyin tea hydrosol, comprising the following steps:

[0015] S.1. Overall Aroma Profile Assessment: The obtained hydrosol sample A was placed in a sample bottle, and several professional judges with intermediate or higher tea taster certificates freely used aroma descriptors to select several key aroma descriptors and score their intensity and overall acceptability. The intensity was divided into 0-2: very weak, 2-4: weak, 4-6: medium, 6-8: strong, and 8-10: very strong. The overall acceptability scores were similar.

[0016] S.2. Separation and identification of aroma substances: SPME was used to separate the hydrosol sample A obtained in step S.2, and then MassHunter workstation software - unknown substance analysis software was used to identify the substances. RI, GC-O and aroma standards were used to qualitatively identify the aroma substances in the sample, and internal standard method (ethyl decanoate) and external standard method were used to quantitatively identify the aroma substances.

[0017] S.3. Aroma Smelling: Aroma smelting tests were conducted using an Agilent 7890GC system combined with GC-O ODP3, and the key substances of several fresh floral fragrances were identified by the aroma intensity AI value;

[0018] S.4. Aroma Reconstitution and Defect: Several key floral aroma compounds identified were added to 25 mL of the CK sample to form spiked sample B. Samples A and spiked sample B were evaluated by multiple professional tea tasters with intermediate or higher certificates based on the aroma descriptors identified in step S.2. In aroma defect, key floral aroma compounds were identified by removing one component at a time from spiked sample B. The contribution of each key floral aroma compound was evaluated using a triangulation test according to ISO 4120:2004, thereby identifying the key floral aroma compounds.

[0019] Furthermore, the key aroma descriptors in step S.1 are floral, fruity, sweet, grassy, ​​baked, and milky aromas, respectively.

[0020] Further, the specific steps of the SPME method in step S.2 are as follows: after equilibration at 60°C for 5 min, the aroma is adsorbed using a divinylbenzene / carboxyl / polydimethylsiloxane extraction head for 55 min, and then desorbed for 5 min at the GC×MS inlet.

[0021] Furthermore, in the method for identifying the Golden Guanyin hydrosol, the gas chromatography-mass spectrometry method in step S.2 is set as follows: DB-5MS column: initial temperature 40℃, injection port temperature 250℃, flow rate 1mL / min, pressure 48.745kPa, splitless injection mode, carrier gas 99.999% pure helium; the temperature program is set as follows: equilibrate at 40℃ for 2min, increase to 96℃ at 2.5℃ / min, hold for 2min, then increase to 126℃ at 3.5℃ / min, hold for 2min, then increase to 230℃ at 6℃ / min, hold for 5min.

[0022] Further, in step S.3, GC-O is performed using a DB-5MS column. The effluent from the capillary column is split into the MS port and the sniffing port at a 1:1 ratio, and the temperature of the transfer line is maintained at 230°C. GC-O mainly includes DFA and OMSE analysis techniques. In the DFA analysis, when an odor is detected twice or more (i.e., the detection frequency DF≥2), it is considered to have a potential contribution to the overall odor characteristics. In the OMSE analysis, if the aroma intensity AI value reaches 3 or higher, the aroma substance is identified as a key contributor.

[0023] The beneficial effects of this invention are mainly reflected in:

[0024] (1) The technology provided by this invention can prepare Jin Guanyin tea hydrosol, extract aroma by HS-SPME extraction and identify by DB-5MS chromatographic column, and at the same time use aroma analysis technology such as DFA and OMSE to determine the main components of the light floral fragrance, ensuring the objectivity and accuracy of the collection and identification results of the key light floral fragrance components.

[0025] (2) This invention further optimizes and limits the preparation conditions of Jin Guanyin tea hydrosol, and obtains the optimal preparation conditions, which are beneficial for use in production.

[0026] (3) The identification method used in this invention is simple to operate and convenient to use, which is conducive to its large-scale promotion in industrial production. Attached Figure Description

[0027] Figure 1 This is a comparison chart of aroma profiles. (Note: The scores of the selected descriptors in the chart were obtained through collective evaluation by 20 group members. The cosine similarity calculation formula is:)

[0028]

[0029] A i and B i These are the i-th aroma intensity values ​​for the tea-scented liquid and the reconstituted liquid, respectively. Detailed Implementation

[0030] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, unless otherwise specified, the following embodiments and features can be combined with each other. Unless otherwise specified, the methods used in the embodiments of the present invention are conventional methods, and the reagents used are commercially available.

[0031] Example 1: A method for preparing and identifying a floral-scented Guanyin hydrosol

[0032] The method is as follows:

[0033] Step 1: Accurately weigh 30g of Jin Guanyin tea leaves, mix them with 90g of purified water in the correct proportion, and let them sit at room temperature for a period of time.

[0034] Step 2: Place the tea sample in a rotary evaporator for extraction. Set the rotation speed to 45 RPM, the evaporation temperature to 50℃, the vacuum degree to 30 mbar, the condensation temperature to -5℃, and the evaporation time to 40 min. Then collect the light floral fragrance type Jin Guan Yin hydrosol A from the rotary evaporation flask.

[0035] Step 3: Sensory evaluation of sample A obtained in Step 1: First, 25 mL of sample was placed in a 50 mL sample bottle. The evaluators (9 men and 11 women, professional evaluators with intermediate or higher tea taster certificates) freely used aroma descriptors, followed by a unified discussion. Several key aroma descriptors were selected and their intensity and overall acceptability were scored. The intensity was divided into 0-2: very weak, 2-4: weak, 4-6: medium, 6-8: strong, and 8-10: very strong. The overall acceptability scores were similar.

[0036] Step 4: Separation and Identification of Aroma Compounds: SPME was used to separate the sample. 5 mL of hydrosol was accurately weighed and placed in a 20 mL extraction flask. Ethyl decanoate (10 μL, 10 ppm) and 1.75 g NaCl were added, and the rotor was placed in the flask, which was then quickly capped. After equilibration in a water bath for 5 min, the aroma was adsorbed for 55 min using a divinylbenzene / carboxyl / polydimethylsiloxane extraction head (50 / 30 μm DVB / CAR / PDMS). After adsorption, the aroma was desorbed for 5 min at the GC×MS inlet. A DB-5MS column was used to separate the volatile components of the sample. MassHunter workstation software—Unknown Substance Analysis software was used for substance identification. RI, GC-O, and aroma standards were used for qualitative analysis of the aroma compounds in the sample. Internal standard method (ethyl decanoate) and external standard method were used for quantitative analysis of the aroma compounds.

[0037] In this step, the gas chromatography-mass spectrometry method is set as follows: DB-5MS column: initial temperature 40℃, injection port temperature 250℃, flow rate 1mL / min, pressure 48.745kPa, splitless injection mode, carrier gas 99.999% pure helium; the temperature program is set as follows: equilibrate at 40℃ for 2min, increase to 96℃ at 2.5℃ / min, hold for 2min, then increase to 126℃ at 3.5℃ / min, hold for 2min, then increase to 230℃ at 6℃ / min, hold for 5min.

[0038] Step 5: In the sample analysis, the Agilent 7890GC system and GC-O ODP3 were used to conduct the aroma smelling test. Before the test, the reviewers were trained on aspects such as recording the retention time of aroma standards, aroma attributes and aroma intensity values, and then smelled the samples on the machine. The main analytical techniques included DFA, OMS E and other analytical techniques.

[0039] In this step: GC-O is performed using a DB-5MS column, with the effluent from the capillary column split at a 1:1 ratio to the MS port and the snoring port, and the transfer line temperature maintained at 230°C; GC-O mainly includes DFA and OMSE analysis techniques. In the DFA analysis, when an odor is detected twice or more (i.e., the detection frequency DF≥2), it is considered to have a potential contribution to the overall odor characteristics; in the OMSE analysis, an aroma intensity AI value of 3 or higher is considered a key contributor to the aroma.

[0040] Step 6: In aroma reconstruction, the key floral aroma compounds identified above were added to 25 mL of the CK sample to form spiked sample B. A panel of 20 trained professional reviewers evaluated sample A and spiked sample B according to the aroma descriptors identified in step 3. In aroma loss, key floral aroma compounds were identified by removing one component at a time from spiked sample B. The contribution of each key floral aroma compound was evaluated by a triangulation according to ISO 4120:2004 (GB / T 12311-2012).

[0041] In Example 1, the extracted Guanyin hydrosol obtained at 55℃ for 40 minutes exhibited a distinct floral fragrance. The overall aroma profile of Sample A was evaluated, and its structure is as follows: Figure 1 As shown, floral, fruity, sweet, grassy, ​​baked, and milky aromas are consistent with the description of the main aromas.

[0042] Table 1. Sensory evaluation results of Jin Guan Yin hydrosol at 150℃ for 40 minutes

[0043]

[0044] Aroma compounds were extracted from the samples using HS-SPME, followed by GC-O olfaction of the hydrosols. Thirty-seven aromatic compounds were identified in sample A, among which indole (floral), linalool (floral), phenylacetaldehyde (floral), leaf alcohol (fresh, leafy), and methyl heptenone (fruity, fresh) had relatively high aroma levels. These compounds are likely key contributors to the fresh floral fragrance of Jin Guan Yin.

[0045] Table 2. AI values ​​of major aroma compounds in sample A

[0046]

[0047]

[0048] To further identify the key components contributing to the floral fragrance of Jin Guan Yin hydrosol, this invention utilizes sensory concepts to characterize the substances exhibiting this fragrance. The aroma cosine similarity between sample B and sample A reached 0.98, indicating a high degree of similarity between the two samples. Sample B model can effectively reproduce the aroma quality of sample A (Table 2). Further omission tests confirmed that jasmonic acid lactone, phenylacetaldehyde, methyl salicylate, hexanal, benzaldehyde, indole, jasmonic acid, methyl heptenone, β-ionone, leaf alcohol, and 1-penten-3-one are key factors affecting the fragrance of fresh flowers, while trans-nerolidol, methyl jasmonic acid, geraniol, linalool, (E,E)-2,4-heptadienal, trans-2-octenal, cis-4-heptadienal, 2-n-propylphenol, acetophenone, 3-nonen-2-one, and 3,5-octadien-2-one are potential factors affecting the fragrance of fresh flowers (Table 2).

[0049] Table 3. Precise Quantification of Key Active Ingredients

[0050]

[0051]

[0052] Table 4. Aroma omission experiment from recombinant model B

[0053]

[0054] *Significance level is expressed as *p<0.05, **p<0.01, and ***p<0.001. Example 2: Effect of different rotary evaporation times on the preparation and identification of Qinghua-scented Guanyin hydrosol.

[0055] The method is as follows:

[0056] Step 1: Accurately weigh 30g of Jin Guanyin tea leaves, mix them with 90g of purified water in the correct proportion, and let them sit at room temperature for a period of time.

[0057] Step 2: Place the tea sample in a rotary evaporator for extraction. Set the rotation speed to 45 RPM, the evaporation temperature to 50℃, the vacuum degree to 30 mbar, the condensation temperature to -5℃, and the evaporation time to 80 min. Then collect the floral-scented Guanyin hydrosol from the rotary evaporation flask.

[0058] Step 3: Sensory evaluation of the sample obtained in Step 1: First, place 25 mL of sample into a 50 mL sample bottle. The evaluator scores the key aroma descriptors and their intensity and overall acceptability. The intensity is divided into 0-2: very weak, 2-4: weak, 4-6: moderate, 6-8: strong, and 8-10: very strong. The overall acceptability scores are similar.

[0059] Step 4: Separation and Identification of Aroma Compounds: SPME was used to separate the sample. 5 mL of hydrosol was accurately weighed and placed in a 20 mL extraction flask. Ethyl decanoate (10 μL, 10 ppm) and 1.75 g of NaCl were added, and the flask was quickly capped. After equilibration in a water bath for 5 min, the aroma was adsorbed using a divinylbenzene / carboxyl / polydimethylsiloxane extraction head (50 / 30 μm DVB / CAR / PDMS) for 55 min. After adsorption, desorption was performed at the GC×MS inlet for 5 min. The volatile components of the sample were separated using a DB-5MS column. The substances were identified using MassHunter workstation software—Unknown Substance Analysis software. RI was used for qualitative analysis of the aroma compounds. Internal standard method (ethyl decanoate) and external standard method were used for quantitative analysis of the aroma compounds.

[0060] In this embodiment, the extracted Guanyin hydrosol has a high floral and fruity aroma, a distinct fresh floral fragrance, and a high overall acceptability (Table 5).

[0061] Table 5. Sensory evaluation results of Golden Guanyin hydrosol at 50℃ for 80 minutes

[0062]

[0063] Subsequently, 11 key components were analyzed. The results showed that among the 11 key components, indole had the highest concentration in the sample (19949.43 μg / L), followed by jasmine lactone (5272.04 μg / L), while β-ionone had the lowest concentration (35.16 μg / L). In terms of OAV, except for methyl salicylate, the OAV of the other 10 key components was greater than 1, with phenylacetaldehyde having the highest (668.97) and methyl salicylate the lowest (0.88) (Table 6).

[0064] Table 6. Concentration of key aroma components in Jin Guan Yin hydrosol at 50℃ for 80 minutes

[0065]

[0066] Example 3: Effect of different rotary evaporation temperatures on the preparation and identification of floral-scented Guanyin hydrosol

[0067] The method is as follows:

[0068] Step 1: Accurately weigh 30g of Jin Guanyin tea leaves, mix them with 90g of purified water in the correct proportion, and let them sit at room temperature for a period of time.

[0069] Step 2: Place the tea sample in a rotary evaporator for extraction. Set the rotation speed to 45 RPM, the evaporation temperature to 70℃, the vacuum degree to 30 mbar, the condensation temperature to -5℃, and the evaporation time to 80 min. Then collect the floral-scented Guanyin hydrosol from the rotary evaporation flask.

[0070] Step 3: Sensory evaluation of the sample obtained in Step 1: First, place 25 mL of sample into a 50 mL sample bottle. The evaluator scores the key aroma descriptors and their intensity and overall acceptability. The intensity is divided into 0-2: very weak, 2-4: weak, 4-6: moderate, 6-8: strong, and 8-10: very strong. The overall acceptability scores are similar.

[0071] Step 4: Separation and Identification of Aroma Compounds: SPME was used to separate the sample. 5 mL of hydrosol was accurately weighed and placed in a 20 mL extraction flask. Ethyl decanoate (10 μL, 10 ppm) and 1.75 g of NaCl were added, and the flask was quickly capped. After equilibration in a water bath for 5 min, the aroma was adsorbed using a divinylbenzene / carboxyl / polydimethylsiloxane extraction head (50 / 30 μm DVB / CAR / PDMS) for 55 min. After adsorption, desorption was performed at the GC×MS inlet for 5 min. The volatile components of the sample were separated using a DB-5MS column. The substances were identified using MassHunter workstation software—Unknown Substance Analysis software. RI was used for qualitative analysis of the aroma compounds. Internal standard method (ethyl decanoate) and external standard method were used for quantitative analysis of the aroma compounds.

[0072] In this embodiment, the extracted Guanyin hydrosol had weak floral and fruity aromas, low floral fragrance, and low overall acceptability (Table 7).

[0073] Table 7. Sensory evaluation results of Golden Guanyin hydrosol at 70℃ for 80 minutes

[0074]

[0075] Subsequently, 11 key components were analyzed. The results showed that indole had the highest concentration in the sample (17919.99 μg / L), followed by jasmine lactone (14535.58 μg / L), while 1-penten-3-one had the lowest concentration (7.57 μg / L). In terms of OAV, two of the 11 key components had an OAV less than 1 (Table 8), including methyl salicylate and benzaldehyde. The component with the highest OAV was phenylacetaldehyde (555.28), and the component with the lowest OAV was methyl salicylate (0.72). The decrease in the concentration of these components is an important reason for the weakening of the delicate floral fragrance of Jin Guan Yin hydrosol.

[0076] Table 8. Concentration of key aroma components in Jin Guan Yin hydrosol at 70℃ for 80 minutes

[0077]

Claims

1. A method for preparing a floral-scented Guanyin tea hydrosol, characterized in that, The preparation method of this tea hydrosol includes the following steps: S.

1. Sample pretreatment: Mix the Jin Guanyin tea sample with purified water in a certain proportion and let it stand for a period of time; S.

2. Hydrosol Extraction: The tea sample obtained in step S.1 is placed in a rotary evaporator for extraction. The condensed hydrosol A of the light floral fragrance Jin Guanyin tea is collected by vacuum distillation.

2. The preparation method according to claim 1, characterized in that, In step S.1, the mass ratio of tea sample to purified water is 1:

3.

3. The preparation method according to claim 2, characterized in that, The room temperature is 25℃±2℃.

4. The preparation method according to claim 1 or 2, characterized in that, The rotary evaporation parameters in step S.2 are: rotation speed 45 RPM, rotary evaporation temperature 40-70℃, vacuum degree 30 mbar, condensation temperature -5℃, and rotary evaporation time 40-80 min.

5. The method described in any one of claims 1-4 is used to prepare a floral-scented Guanyin tea hydrosol.

6. The method for identifying a floral-scented Guanyin tea hydrosol as described in claim 5, characterized in that, Includes the following steps: S.

1. Overall Aroma Profile Assessment: The obtained hydrosol sample A was placed in a sample bottle, and several professional judges with intermediate or higher tea taster certificates freely used aroma descriptors to select several key aroma descriptors and score their intensity and overall acceptability. The intensity was divided into 0-2: very weak, 2-4: weak, 4-6: medium, 6-8: strong, and 8-10: very strong. The overall acceptability scores were similar. S.

2. Separation and identification of aroma substances: SPME was used to separate the hydrosol sample A obtained in step S.2, and then MassHunter workstation software - unknown substance analysis software was used to identify the substances. RI, GC-O and aroma standards were used to qualitatively identify the aroma substances in the sample, and internal standard method and external standard method were used to quantitatively identify the aroma substances. S.

3. Aroma Smelling: Aroma smelting tests were conducted using an Agilent 7890GC system combined with GC-O ODP3, and the key substances of several fresh floral fragrances were identified by the aroma intensity AI value; S.

4. Aroma Reconstitution and Defect: Several key floral aroma substances identified were added to 25 mL of CK sample to form spiked sample B. Sample A and spiked sample B were evaluated by several professional judges with intermediate or higher tea taster certificates according to the aroma descriptors identified in step S.

2. In aroma loss, key floral fragrance compounds were identified by removing one component at a time from spiked sample B. The contribution of each key floral fragrance compound was evaluated using a triangulation test according to ISO 4120:2004, thereby identifying the key floral fragrance compounds.

7. The identification method as described in claim 6, characterized in that, The key aroma descriptors in step S.1 are floral, fruity, sweet, grassy, ​​baked, and milky.

8. The identification method as described in claim 6, characterized in that, The specific steps of the SPME method in step S.2 are as follows: after equilibration at 60°C for 5 min, the aroma is adsorbed using a divinylbenzene / carboxyl / polydimethylsiloxane extraction head for 55 min, and then desorbed for 5 min at the GC×MS inlet.

9. The identification method as described in claim 8, characterized in that, The gas chromatography-mass spectrometry method in step S.2 is set as follows: DB-5MS column: initial temperature 40℃, injection port temperature 250℃, flow rate 1mL / min, pressure 48.745kPa, splitless injection mode, carrier gas 99.999% pure helium; the temperature program is set as follows: equilibrate at 40℃ for 2min, increase to 96℃ at 2.5℃ / min, hold for 2min, then increase to 126℃ at 3.5℃ / min, hold for 2min, then increase to 230℃ at 6℃ / min, hold for 5min.

10. The identification method as described in claim 6, 7, or 8, characterized in that, In step S.3, GC-O is performed using a DB-5MS column. The effluent from the capillary column is split into the MS port and the sniffer port at a 1:1 ratio, and the temperature of the transfer line is maintained at 230°C. GC-O mainly includes DFA and OMSE analysis techniques. In the DFA analysis, when an odor is detected twice or more (i.e., the detection frequency DF≥2), it is considered to have a potential contribution to the overall odor characteristics. In the OMSE analysis, if the aroma intensity AI value reaches 3 or higher, the aroma substance is identified as a key contributor.

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