TWI679407B - Analyzing Method for Aroma of Flower - Google Patents

Abstract

A flower aroma analysis method includes: arranging a flower sample and an adsorption fiber in a closed container, leaving the closed container having the flower sample and the adsorption fiber for a period of time, removing the flower sample to form an adsorption of the aroma with the flower sample attached Fiber, desorb the aroma from the adsorbed fiber, and perform gas chromatography analysis on the desorbed aroma to obtain the chromatographic result.

Description

Flower aroma analysis method

The invention relates to a method for odor analysis, in particular to a method for analyzing flower aroma.

In the conventional odor analysis, the sample to be analyzed must be taken into the laboratory. After the sample is heated to volatilize the odor, the volatilized odor is brought into the relevant analysis instrument by gas for further analysis. However, some samples are not suitable for heating, or cannot be brought into the laboratory due to some factors, which will cause analysis difficulties.

In one embodiment, a flower aroma analysis method includes: placing a flower sample and an adsorbing fiber together in a closed container, leaving the closed container with the flower sample and the adsorbing fiber to stand for a period of time, and removing the flower sample to form an attachment The aroma adsorption fibers of the flower sample, the aroma was desorbed from the adsorbed fibers, and the desorbed aroma was analyzed by gas chromatography to obtain the chromatographic results. It is not necessary to forcibly extract the aroma by heating the flower sample, and it can be directly operated at the place of origin of the flower sample. By forming the adsorption fiber with the aroma, it can be more easily stored or carried, and it is more convenient for analysis.

In summary, the method for analyzing the aroma of flowers provided by any embodiment of the present invention can allow the aroma to be stored for at least three days and still have a sufficient concentration, and it can be analyzed smoothly even when it is difficult to obtain a long-distance or flower sample. , And the operation is simpler. According to an embodiment of the present invention, it can be judged whether the quality of jasmine flowers is excellent.

FIG. 1 is a flowchart of a flower aroma analysis method according to an embodiment of the present invention. Referring to FIG. 1, in an embodiment, in a method for analyzing a flower aroma, first, a flower sample and an adsorption fiber are placed in a closed container (step S1). In one embodiment, the adsorption fiber is a material that has an adsorption effect on volatile substances (aromas). For example, the adsorption fiber may be Twister made of PDMS, DVB / CAR / PDMS composite fiber, DVB / PDMS composite, EG-made Twister or Tenax TA ^TM adsorption tube, Tenax GR ^TM adsorption tube, Carbopack ^TM B & X adsorption tube, etc. In one embodiment, the sealed container is a light-tight sealed container, such as a dark glass jar. In one embodiment, the closed container has a capacity of 15 ml or more, so that in addition to containing the adsorption fibers, a sufficient space can be provided for holding a sample of flowers. Preferably, the volume of the closed container is 20 ml. In one embodiment, the total volume of the flower sample is greater than the total volume of the adsorbed fibers. In one embodiment, the flower sample is in direct contact with the adsorbent fiber. Preferably, the flower sample is wrapped around the absorbent fiber. More preferably, the closed container is filled with flower samples and absorbent fibers. In one embodiment, a suitable pressure is applied when filling the flower sample, so that the density of the flower sample in the closed container is increased. In an embodiment, the closed container includes a main body and a cover body. After a part of the flower sample is placed inside the body, the adsorption fiber is placed on the flower sample, and the remaining flower sample fills other spaces inside the body, and The cover is connected with the body to make the inside of the body hermetically sealed.

Next, the closed container having the flower sample and the adsorption fiber is allowed to stand for a period of time (step S2). Preferably, the above period of time is more than 3 hours, so that the adsorption fiber can adsorb sufficient aroma. More preferably, the period of time is 3 to 5 hours. In some embodiments, the closed container with the flower sample and the adsorption fiber is left in an environment of 30 ° C. or higher for a period of time, and the appropriate ambient temperature is more conducive to the release of volatile substances (fragrance) in the flower sample.

After that, the flower sample is removed from the closed container to form an absorbent fiber with the aroma of the flower sample (step S3). In order to prevent the flower sample from deteriorating under long-term standing, it will release a bad odor and affect the subsequent Analysis, so after the adsorption fiber has adsorbed a sufficient amount of aroma, the flower sample can be removed.

FIG. 2 is a flowchart of an embodiment of step S3. Referring to FIG. 3, in an embodiment, step S3 includes: transferring the adsorbent fiber with fragrance from a closed container into a storage bottle (step S31) and refrigerating the storage bottle having the adsorbent fiber with fragrance (step S32). Here, the refrigerated low temperature can further stabilize the aroma attached to the adsorbent fiber, so that the adsorbent fiber stored in the storage bottle can retain sufficient aroma for analysis after 3 to 5 days. In one implementation, refrigerating refers to keeping the storage bottle in an environment below 10 ° C., for example: a refrigerator for a general household refrigerator, a portable ice pack, and the like.

Next, the fragrance is desorbed from the adsorption fiber (step S4). In one embodiment, the inert gas below 0 ° C is used to desorb the aroma from the adsorbent fiber, so that the aroma is not easy to volatilize too much at the injection port. Preferably, the aroma is desorbed from the adsorbent fiber using nitrogen at -30 ° C.

Finally, the desorbed aroma is subjected to gas chromatography to obtain a chromatography result (step S5). Here, the desorbed aroma can be carried by a carrier helium into a gas chromatography machine (CG / MS) for gas chromatography analysis. Here, the chromatographic result is an analysis map, and there will be multiple peaks on the analysis map. Each of the peaks represents one of the volatile substances included in the aroma.

Fig. 3 is an analysis chart of an exemplary jasmine green tea. Jasmine tea refers to a kind of tea made from the aroma of jasmine and transformed into tea embryos after the operation of the jasmine flower. Referring to Figure 3, Figure 3 shows the chromatographic results of jasmine tea obtained by bringing the standard high-quality jasmine green tea into the laboratory and directly performing gas chromatography analysis. Based on this, we can know that the representative aroma in jasmine green tea The indicators include Linalool A51, Benzyl acetate A52 and Cis 3 hexenyl benzoate A53. Therefore, the jasmine flowers that can be used as the raw material of jasmine green tea must also have at least a linalool index, a phenylyl acetate index, and a cis 3 hexenyl benzoate index.

4 is a flowchart of a flower aroma analysis method according to an exemplary embodiment of the present invention. Because the main origin of jasmine flowers is more than in remote areas, and the flavor degradation occurs 3 to 5 hours after the jasmine flowers are fully opened, it is not easy to sample and analyze immediately. Therefore, the aroma analysis of jasmine flowers of different origins will be performed according to the steps of the exemplary method for analyzing the aroma of flowers in FIG. 4.

Here, Jasmine No. 1 (origin: Vietnam), Jasmine No. 2 (origin: Taiwan), Jasmine No. 3 (origin: India A area), and Jasmine No. 4 (origin: India B area) are used as flowers. sample.

A gas chromatography mass spectrometry (Gas chromatography mass spectrometry) machine is used in the experiment of the exemplary example, and the manufacturer is Agilent. It includes GC (Gas chromatography, model 7890B) and MS (Mass spectrometry, model 5977A). As the adsorption fiber, a tenax TA ^™ adsorption tube (Gerstel) was used. The closed container was a 40 ml brown glass jar.

Continued referring to FIG. 4. First, a closed container is filled with a flower sample and an adsorption fiber (step S11). Here, a fresh jasmine flower that has been completely opened at the place of production is used as a flower sample. A part of the jasmine flower is placed in a brown glass jar, and the adsorption tube is also placed in the brown glass jar. Next, take the remaining jasmine flowers to fill the gap between the brown glass jar and the adsorption tube, so that the outer surface of the adsorption tube can be covered by the jasmine flowers, and the pressure is applied to make the jasmine flowers more dense and filled. The jasmine flower is about 5g ~ 10g, and finally the lid of the brown glass jar is joined with the bottle body to achieve a closed state.

Next, the sealed container is left to stand at 30 ° C to 50 ° C for 3 to 5 hours (step s21). Here, since the jasmine flowers are abundant in summer (for example, the outdoor temperature in Vietnam is about 35 ° C ~ 40 ° C), the sealed container completed in step S11 is left at room temperature for 3 ~ 5 hours so that the attached fiber can Try to absorb as much aroma as possible.

Also, the jasmine flowers start to deteriorate after 5 hours due to the high temperature. Therefore, the jasmine flowers in the closed container are discarded afterwards, and the adsorption tube is taken out and transferred to another storage bottle (step S31). Here, the storage bottle is hermetically closed to prevent leakage of aroma from the adsorption tube. In addition, the storage bottle having the adsorbent fiber having an aroma is stored at a temperature of 10 ° C. or lower (step S33), that is, the storage tube and the storage bottle can be placed in a refrigerator controlled at 4 ° C. and refrigerated. Here, the adsorption tube contained in the storage bottle can be left for 3 to 5 days as required. For example, when returning from Vietnam to Taiwan, the adsorption tube containing the aroma is returned to the laboratory for further analysis.

Finally, the aroma is desorbed from the adsorbed fiber using nitrogen at -30 ° C (step S41), and gas chromatography is performed on the desorbed aroma to obtain a chromatography result (step S5). Here, the adsorption tube is clamped into an injection port (Thermal Desorption Unit, TDU), and thermal desorption is performed in the TUD by the full injection method. Among them, the desorption is performed by the gradient warming method, and the initial temperature of the TDU is set to 30. ℃, heat up to 280 ° C for 1 minute and maintain for 3 minutes, then use the CIS (Cooled Injection System) to reduce the temperature of the aroma with liquid nitrogen to -30 ° C for 30 seconds, and then increase the temperature by 12 ° C / second The temperature was raised to 280 ° C and entered the gas chromatograph in a full injection mode. An Agilent HP 5MS column (length 30 m / inner diameter 250 μm / film thickness 0.25 μM) was used. The initial velocity of the column was 1.5 ml / min, and the column pressure was 12.675 psi (Pounds per square inch). The heating program of the oven is as follows:

Table I Heating rate (℃ / min) Temperature (℃) Holding time (minutes) 50 5 5 180 3 10 280 3

It can be known from Table 1 that the capillary column is heated in a stepwise manner during the separation process to obtain the result of separating the compounds. First, the starting temperature was maintained at 50 ° C for 5 minutes. Next, the temperature was raised to 180 ° C at a temperature increase rate of 5 ° C / min, and the rise time was 26 minutes, and maintained at 180 ° C for 3 minutes. Then, the temperature was raised to 280 ° C at a temperature increase rate of 10 ° C / min, and the rise time was 10 minutes, and the temperature was maintained at 280 ° C for 3 minutes.

The setup conditions of the mass spectrometer can be divided into the following three parts: (1) Enter the ion source through the end of the capillary column of the gas chromatograph, and set the connection channel temperature from the column to the ion source at 280 ° C; (2) Ionization : EI (electron ionization) is used to ionize molecules with a voltage of 70 volts, and the temperature of the ion source is controlled at 230 ° C; (3) Quadrupole mass analyzer: collects the mass-to-charge ratio (m / z) range Ion fragments between 40 and 400 are detected by a detector, and the temperature of the detector is set to 150 ° C. According to the above-mentioned set conditions, the chromatographic results (analysis spectrum) of the aroma of the flower sample can be obtained.

Therefore, the x-axis of the chromatogram is time, and the y-axis is the intensity of the separated ion signal (abundance relative intensity). There will be multiple peaks on the map. One of the volatile substances included in the aroma, the higher the peak height of the graph, the more the above-mentioned volatile substances.

FIG. 5 is an analysis chart of Jasmine No. 1 according to an exemplary example. Fig. 6 is an analysis chart of Jasmine No. 2 according to an exemplary example. The quality of jasmine green tea is greatly affected by the quality of jasmine flowers and the control technology. Currently available jasmine green tea on the Taiwan market is mainly produced in Taiwan and Vietnam. 5 and 6 are analysis maps obtained from the jasmine flower No. 1 (origin: Vietnam) and the jasmine flower No. 2 (origin: Taiwan) according to the flower aroma analysis method of the exemplary example. In Figure 5 and Figure 6, there are linalool index (A11, A21), phenyl acetate index (A12, A22) and cis-3-hexenyl benzoate index (A13, A23), that is, It is said that both Jasmine No.1 and No.2 meet the requirements of fresh jasmine fragrance. If this jasmine flower is used and matched with appropriate brewing technology, it can produce high-quality jasmine green tea that meets Chinese tastes.

Fig. 7 is an analysis chart of Jasmine No. 3 according to an exemplary example. Fig. 8 is an analysis chart of Jasmine No. 4 according to an exemplary example. In view of the decreasing production of jasmine flowers from Taiwan and Vietnam, in order to develop other high-quality jasmine green tea sources, the flower aroma analysis method of the exemplary embodiment of the present invention can more easily operate people to complete the sampling of fresh jasmine flowers locally, The analysis is performed to obtain an analysis map. For example, referring to FIGS. 7 and 8 are analysis maps obtained from the jasmine flower No. 3 (origin: India region A) and the jasmine flower No. 4 (origin: India region B) according to the flower aroma analysis method of the exemplary example. In FIG. 7, only the linalool index (A31) and the phenyl acetate index (A32) are provided, but the cis-3-hexenol benzoate index is lacking. In FIG. 8, only the linalool index (A41) is provided, but the phenyl acetate index and the cis-3-hexenol benzoate index are lacking. In other words, No. 3 Jasmine Flowers and No. 4 Jasmine Flowers do not meet the requirements of fresh jasmine fragrance. If this Jasmine flower is used, it is not suitable for making high-quality jasmine green tea that meets the taste of Chinese people.

 S1  Store flower samples and absorbent fibers in airtight containers  S2  Let stand for a while in a closed container with flower samples and adsorbed fibers  S3  Flower samples are removed from the closed container to form an absorbent fiber with the aroma of the flower sample  S31  Transfer the scented absorbent fiber from a closed container into a storage bottle  S32  Refrigerated storage bottles with aroma-absorbing fibers  S33  Store storage bottles with aroma-absorbing fibers at a temperature of 10 ° C or lower  S4  Desorb aroma self-adsorbing fibers  S41  Remove the aroma from the adsorbed fiber with nitrogen gas at -30 ℃  S5  Gas chromatographic analysis of desorbed aroma to obtain chromatographic results  A11  Linalool index  A21  Linalool index  A31  Linalool index  A41  Linalool index  A51  Linalool index  A12  Phenyl acetate index  A22  Phenyl acetate index  A32  Phenyl acetate index  A52  Phenyl acetate index  A13  Index of cis-3-hexenol benzoate  A23  Index of cis-3-hexenol benzoate  A53  Index of cis-3-hexenol benzoate

[Fig. 1] is a flowchart of a flower aroma analysis method according to an embodiment of the present invention; [Fig. 2] is a flowchart of an embodiment of step S3; [Fig. 3] is an analysis chart of an exemplary jasmine green tea; [Fig. 4] is a flowchart of a method for analyzing the aroma of flowers according to an exemplary embodiment of the present invention; [Fig. 5] is an analysis chart of No. 1 jasmine in an exemplary embodiment; [Fig. 6] is an analysis chart of No. 2 jasmine in an exemplary embodiment; FIG. 7 is an analysis chart of Jasmine No. 3 in an example; and [FIG. 8] analysis chart of Jasmine No. 4 in an example.

Claims (8)

A method for analyzing the aroma of a flower includes: placing a flower sample and an adsorption fiber in a closed container, wherein the flower sample is a jasmine flower; and leaving the closed container with the flower sample and the adsorption fiber for a period of time; The closed container transfers the adsorption fiber with the fragrance into a storage bottle; and refrigerates the storage bottle with the fragrance fiber; desorbs the fragrance from the adsorption fiber; and desorbs the adsorption fiber. The aroma was subjected to a gas chromatography analysis to obtain a chromatography result. The flower aroma analysis method according to claim 1, wherein the closed container is an opaque closed container. The flower aroma analysis method according to claim 1, wherein the period is 3 to 5 hours. The flower aroma analysis method according to claim 3, wherein the step of leaving the closed container with the flower sample and the adsorption fiber for a period of time includes: leaving the closed container at 30 to 50 ° C for 3 to 5 hours. hour. The flower aroma analysis method according to claim 1, wherein the step of refrigerating the storage bottle having the aroma of the adsorption fiber includes storing the storage bottle having the aroma of the adsorption fiber at a temperature of 10 ° C or lower . The flower aroma analysis method according to claim 1, wherein the adsorption fiber is a PDMS material Twister, an EG material Twister, or a Tenax TA ^TM adsorption tube. The flower aroma analysis method according to claim 1, wherein the step of accommodating the flower sample and the adsorption fiber in the closed container includes: filling the closed container with the flower sample and the adsorption fiber. The flower aroma analysis method according to claim 1, further comprising: comparing whether the chromatography result meets a condition of fresh jasmine fragrance, wherein the condition of fresh jasmine fragrance includes the presence of a linalool index, acetic acid Benzyl acetate and Cis 3 hexenyl benzoate.