TWI729717B - Analyzing method for aroma of dough and system of the same - Google Patents

Abstract

The present invention provides a dough flavor analysis method, which includes placing a dough sample in a closed container; preheating the dough sample to generate at least one aroma substance; placing an adsorption element in the closed container to contact and adsorb the at least one Aroma substance; heating the adsorption element for adsorbing the at least one aroma substance to desorb the at least one aroma substance from the adsorption element; and analyzing the desorbed at least one aroma substance by gas chromatography.

Description

Analysis method and system of dough flavor

A dough flavor analysis method, more specifically, a dough flavor analysis method with improved resolution.

Generally, when making bread or other pasta products, the dough is fermented. Good fermented dough products have rich and layered flavors and are extremely popular in the market.

The detection of food aroma in the conventional technology usually uses gas chromatography with mass spectrometer for analysis. The aroma source of fermented dough is mainly alcohol, aldehyde, acid and other highly volatile organic compounds, so it can also be analyzed by gas chromatography with mass spectrometer. However, these highly volatile organic compounds often cannot be separated from each other in the chromatography process, which increases the difficulty in identifying the aroma components in food or dough.

Therefore, how to improve the resolution and accuracy of the dough flavor analysis method and improve the efficiency of the analysis method is one of the research topics in the industry.

The first aspect of the present invention provides a method for analyzing the flavor of dough, including:

Place the dough sample in a closed container; wherein the weight of the dough sample is less than 0.5 g;

Preheating the dough sample to produce at least one aroma substance;

Placing the adsorption element in the airtight container to contact and adsorb the at least one aroma substance;

Raising the temperature of the adsorption element for adsorbing the at least one aroma substance, so that the at least one aroma substance is desorbed from the adsorption element; and

The desorbed at least one aroma substance is analyzed by gas chromatography.

According to an embodiment of the present invention, the preparation method of the dough sample includes: preparing the dough; and directly taking the portion of the dough less than 0.5 g, wherein the portion less than 0.5 g is the dough sample.

According to an embodiment of the present invention, the weight of the dough sample is not more than 0.3 g.

According to an embodiment of the present invention, the step of preheating the dough sample includes: preheating the dough sample for a first predetermined time; and rotating the closed container within the first predetermined time to generate at least one aroma substance.

According to an embodiment of the present invention, the step of rotating the airtight container within the first predetermined time to generate at least one aroma substance includes: rotating the airtight container intermittently during the first predetermined time to generate at least An aroma substance.

According to an embodiment of the present invention, the rotation speed of the airtight container is greater than 0 rpm to 1000 rpm.

According to an embodiment of the present invention, the first predetermined time is less than 5 minutes.

According to an embodiment of the present invention, the step of placing the adsorption element in the airtight container to contact and adsorb the at least one aroma substance includes: placing the adsorption element in the airtight container for a second predetermined time; and For a second predetermined time, the dough sample is blown with a predetermined flow rate of gas, so that the adsorption element adsorbs the at least one aroma substance.

According to an embodiment of the present invention, the adsorption element is an activated carbon adsorption screen.

According to one embodiment of the present invention, the step of raising the temperature of the adsorption element for adsorbing the at least one aroma substance to desorb the at least one aroma substance from the adsorption element includes: During a third predetermined time, the adsorption element for adsorbing the at least one aroma substance is heated in a gradient manner, so that the at least one aroma substance is desorbed from the adsorption element.

According to an embodiment of the present invention, the gradient heating includes increasing the temperature of the adsorption element for adsorbing the at least one aroma substance by at least 250° C. within 1 minute.

According to one embodiment of the present invention, the step of raising the temperature of the adsorption element for adsorbing the at least one aroma substance to desorb the at least one aroma substance from the adsorption element further comprises: cooling the at least one desorbed from the adsorption element Aroma substances.

According to an embodiment of the present invention, the step of analyzing the desorbed at least one aroma substance by gas chromatography includes: heating the desorbed at least one aroma substance to a predetermined temperature; and analyzing the desorbed at least one aroma substance by gas chromatography. At least one aroma substance heated to the predetermined temperature.

The second aspect of the present invention provides a dough flavor analysis system for implementing the dough flavor analysis method described in the first aspect of the present invention. The analysis system includes:

The sampling unit includes a first accommodating space and a first heating element; wherein the first accommodating space is used to place a dough sample, and the first heating element is used to adjust the temperature of the dough sample to generate at least one aroma substance;

The adsorption element is placed in the first accommodating space for contacting and adsorbing the at least one aroma substance;

The desorption unit includes a second accommodating space and a second heating element; wherein the second accommodating space is used for placing the adsorption element for adsorbing the at least one aroma substance, and the second heating element is used for adjusting the adsorption The temperature of the adsorption element of the at least one aroma substance to desorb the at least one aroma substance; and

The analysis unit is used to analyze the at least one aroma substance.

According to an embodiment of the present invention, the sampling unit further includes a rotating element for adjustable rotation of the first accommodating space.

According to an embodiment of the present invention, the sampling unit further includes a blowing element for conveying gas into the first accommodating space to blow the dough sample.

According to an embodiment of the present invention, the second heating element is used to gradually increase the temperature of the adsorption element for adsorbing the at least one aroma substance to desorb the at least one aroma substance.

According to an embodiment of the present invention, the desorption unit further includes a cooling element for cooling the desorbed at least one aroma substance.

According to an embodiment of the present invention, the second heating element is multiplexed to increase the temperature of the at least one aroma substance that has been cooled.

According to an embodiment of the present invention, the analysis unit includes a gas chromatograph.

Compared with the prior art, the dough flavor analysis method and system provided by the present invention requires only a small amount of samples, no additional extraction processing, and can provide high-resolution and accurate analysis of various aroma components in the dough .

The following specific examples illustrate the implementation of the present invention. Those familiar with the art can easily understand the other advantages and effects of the present invention from the contents disclosed in this specification.

It should be noted that the structure, ratio, size, etc. shown in the drawings in this manual are only used to match the content disclosed in the manual for the understanding and reading of those who are familiar with the art, and are not intended to limit the implementation of the present invention. Therefore, it does not have any technical significance. Any structural modification, proportional relationship change or size adjustment shall fall within the present invention without affecting the effects and objectives that can be achieved by the present invention. The technical content disclosed must be within the scope of coverage. At the same time, the terms such as “upper”, “inner”, “outer”, “bottom”, and “一” cited in this specification are only for clarity of description, and are not used to limit the implementation of the present invention. The scope, the change or adjustment of the relative relationship, shall be regarded as the scope of the implementation of the present invention without substantive changes to the technical content, and shall be described first.

Please refer to FIG. 1, which is a flowchart of a dough flavor analysis method according to an exemplary embodiment of the present invention. The first aspect of the present invention provides a dough flavor analysis method, including:

S10 Provide samples: place the dough sample in a closed container; the weight of the dough sample is less than 0.5 g.

According to an exemplary embodiment of the present invention, the preparation method of the dough sample may include: preparing dough; and directly taking a portion of the dough less than 0.5 g, wherein the portion less than 0.5 g is the dough sample.

According to a preferred embodiment of the present invention, the dough sample can be taken directly from the prepared dough without using solvent pretreatment. For example, the present invention does not need to use water, organic solvents or similar solvents to extract aroma substances in the dough.

According to the present invention, the sample weight of the dough can be adjusted according to the characteristics of the dough to be tested. Preferably, the weight of the dough sample may not be greater than 0.3 g. For example, when the moisture content of the dough to be tested is 30%, the dough sample weight can be 0.3 g or less; or when the moisture content of the dough to be tested is 50%, the dough sample weight can be 0.2 g or less.

According to the present invention, the weight of the dough sample can preferably be greater than 0 g ~ 0.4 g, greater than 0 g ~ 0.3 g, greater than 0 g ~ 0.2 g, greater than 0 g ~ 0.1 g.

According to the present invention, the weight of the dough sample is preferably not less than 0.05 g.

According to a preferred embodiment of the present invention, the weight of the dough sample may be 0.1 g to 0.2 g.

According to the present invention, the sealed container can be tightly closed after capping the sample bottle. For example, the cap can be a plastic bottle cap or a metal bottle cap, such as an aluminum bottle cap. According to the present invention, the sample bottle can be a screw-top bottle or a crimp-top bottle. According to the present invention, a gasket can be added to the bottle cap.

S20 Preheat the sample: Preheat the dough sample to produce at least one aroma substance.

According to an exemplary embodiment of the present invention, the step of preheating the sample may include: preheating the dough sample for a first predetermined time; and rotating the closed container within the first predetermined time to generate at least one aroma substance.

According to an embodiment of the present invention, the preheating temperature may be 80°C.

According to an embodiment of the present invention, the rotation speed of the closed container may be greater than 0 rpm to 1000 rpm.

According to an embodiment of the present invention, the rotation speed of the closed container may preferably be 100 rpm, 200 rpm, 250 rpm, 300 rpm, 350 rpm, 400 rpm, 450 rpm, 500 rpm, 550 rpm, 600 rpm, 650 rpm, 700 rpm, 750 rpm, 800 rpm, 900 rpm or 1000 rpm.

According to a preferred embodiment of the present invention, the rotation speed of the closed container may be 500 rpm.

According to an embodiment of the present invention, the first predetermined time is less than 5 minutes.

According to a preferred embodiment of the present invention, the first predetermined time may be 1 minute to 2 minutes, 1 minute to 3 minutes, 1 minute to 4 minutes, or 1 minute to 5 minutes.

According to a preferred embodiment of the present invention, the first predetermined time may be 2 minutes.

According to an embodiment of the present invention, the step of preheating the sample may include: preheating the dough sample for a first predetermined time; and rotating the closed container intermittently during the first predetermined time to generate at least one aroma substance.

According to the present invention, the intermittent rotation can be performed in a turn-stop manner. For example, turn for 1 second to 5 seconds, then stop for 1 second to 5 seconds, turn for 1 second to 5 seconds, and then stop for 1 second to 5 seconds, and repeat the turn-stop procedure within the first predetermined time.

S30 Adsorption: placing the adsorption element in the airtight container to contact and adsorb the at least one aroma substance.

According to an exemplary embodiment of the present invention, the adsorption step includes: placing the adsorption element in the airtight container for a second predetermined time; and during the second predetermined time, blowing the dough sample with a predetermined flow rate of gas to The adsorption element is made to adsorb the at least one aroma substance.

According to an embodiment of the present invention, the gas may be hydrogen, nitrogen, helium, or a mixture thereof.

According to a preferred embodiment of the present invention, the gas may be helium.

According to the present invention, the predetermined flow rate may be 50 mL/min~100 mL/min, 60 mL/min~100 mL/min, 70 mL/min~100 mL/min, 80 mL/min~100 mL/min, or 90 mL/min~100 mL/min. mL/min~100 mL/min.

According to a preferred embodiment of the present invention, the predetermined flow rate may be 100 mL/min.

According to a preferred embodiment of the present invention, the second predetermined time may be 10 minutes to 30 minutes or 20 minutes to 30 minutes.

According to a preferred embodiment of the present invention, the second predetermined time may be 30 minutes.

According to the present invention, the material of the adsorption element may include but is not limited to at least one, such as activated carbon, polydimethylsiloxane (PDMS), styrene-divinylbenzene copolymer (CW), divinylbenzene (DVB) , Porous polymer, or the like; or a composite thereof.

According to a preferred embodiment of the present invention, the material of the adsorption element may include but is not limited to at least one activated carbon or porous polymer. The activated carbon may include, but is not limited to, for example: Carbosieve series products, such as Carbosieve S-III, Carbosieve S-II, Carbosieve G, etc.; Carboxen series products, such as Carboxen-563, Carboxen-564, Carboxen-569, Carboxen- 1000, Carboxen 1001, Carboxen-1002, Carboxen-1003, Carboxen-1016, Carboxen-1018, etc.; Carbopack series products, such as Carbopack F, Carbopack C, Carbopack Y, Carbopack B, Carbopack X, etc.; coconut shell activated carbon; Petroleum activated carbon; or its analogues. The porous polymer may include, but is not limited to, for example: Tenax TA, Tenax GR; Porapak N; Chromosorb 106; Hayesep D; glass beads; silica gel; or the like.

According to a preferred embodiment of the present invention, the adsorption element can be an activated carbon adsorption screen.

According to a preferred embodiment of the present invention, the adsorption element can be a composite activated carbon adsorption screen.

According to the present invention, the adsorption step can allow the adsorption element to be inserted into the airtight container, and the adsorption element can contact and adsorb the at least one aroma substance in an environment with a preheating temperature, such as 80°C.

S40 Desorption: increasing the temperature of the adsorption element that adsorbs the at least one aroma substance, so that the at least one aroma substance is desorbed from the adsorption element.

According to an exemplary embodiment of the present invention, the desorption step may include: within a third predetermined time, increasing the temperature of the adsorption element for adsorbing the at least one aroma substance in a gradient manner, so that the at least one aroma substance is adsorbed from the at least one aroma substance. Component desorption.

According to the present invention, the gradient heating includes increasing the temperature of the adsorption element for adsorbing the at least one aroma substance by at least 250° C. from the initial temperature within 1 minute.

According to a preferred embodiment of the present invention, the desorption step may further include: cooling the at least one aroma substance desorbed from the adsorption element.

According to an embodiment of the present invention, the desorption step may include setting the initial temperature of the adsorption element for adsorbing the at least one aroma substance to 40°C. According to the analysis method provided by the present invention, the adsorption element for adsorbing the at least one aroma substance can be heated to 300° C. within 1 minute and maintained for several minutes to desorb the at least one aroma substance from the adsorption element. The desorbed at least one aroma substance can be further cooled to -40°C and maintained for tens of seconds (for example, 30 seconds).

According to the present invention, the at least one aroma substance is often a volatile compound, so the step of cooling can avoid the volatilization of the volatile compound, and the desorbed at least one aroma substance is treated at a low temperature for a period of time (for example, 30 seconds) Helps solidify the sample and concentrate the substance to be tested.

According to the present invention, liquid nitrogen can be used to cool the temperature.

S50 Analysis: Analyze the desorbed at least one aroma substance by gas chromatography.

According to an exemplary embodiment of the present invention, the step of analyzing includes: heating the desorbed at least one aroma substance to a predetermined temperature; and analyzing the at least one aroma substance heated to the predetermined temperature by a gas chromatography method.

According to a preferred embodiment of the present invention, the step of analyzing can analyze the desorbed at least one aroma substance by a gas chromatography-tandem mass spectrometry method.

It should be understood that those skilled in the art know that the condition settings of gas chromatography or mass spectrometry may be adjusted due to different substances to be tested and different instrument brands used, so I will not repeat them here. Without affecting the effects that can be produced by the present invention and the goals that can be achieved, the change or adjustment of the relative setting parameter relationship should be regarded as the scope of the present invention.

Please refer to FIG. 2 again, which is a schematic diagram of the dough flavor analysis system provided by the present invention. The second aspect of the present invention provides a dough flavor analysis system for performing the dough flavor analysis method described in the first aspect of the present invention. The analysis system includes: a sampling unit 10, an adsorption element 20, a desorption unit 30, and an analysis Unit 40.

The sampling unit 10 may include a first accommodating space 11 and a first heating element 12; wherein, the first accommodating space 11 can be used to place a dough sample 50, and the first heating element 12 can be used to adjust the value of the dough sample 50 Temperature to produce at least one aroma substance 51.

The first accommodating space 11 may be a closed container. The airtight container can be tightly closed after capping the sample bottle. For example, the cap can be a plastic bottle cap or a metal bottle cap, such as an aluminum bottle cap. According to the present invention, the sample bottle can be a screw-top bottle or a crimp-top bottle. According to the present invention, a gasket can be added to the bottle cap.

The weight of the dough sample 50 may preferably be less than 0.5 g, greater than 0 g ~ 0.4 g, greater than 0 g ~ 0.3 g, greater than 0 g ~ 0.2 g, greater than 0 g ~ 0.1 g.

According to the present invention, the weight of the dough sample 50 may preferably be not less than 0.05 g.

According to a preferred embodiment of the present invention, the weight of the dough sample 50 can be 0.1 g to 0.2 g.

The adsorption element 20 can be placed in the first accommodating space 11 to contact and adsorb the at least one aroma substance 51.

According to the present invention, the material of the adsorption element 2 may include but is not limited to at least one, such as activated carbon, polydimethylsiloxane (PDMS), styrene-divinylbenzene copolymer (CW), divinylbenzene (DVB) ), porous polymer, or the like; or a composite thereof.

According to a preferred embodiment of the present invention, the material of the adsorption element 20 may include but is not limited to at least one activated carbon or porous polymer. The activated carbon may include, but is not limited to, for example: Carbosieve series products, such as Carbosieve S-III, Carbosieve S-II, Carbosieve G, etc.; Carboxen series products, such as Carboxen-563, Carboxen-564, Carboxen-569, Carboxen- 1000, Carboxen 1001, Carboxen-1002, Carboxen-1003, Carboxen-1016, Carboxen-1018, etc.; Carbopack series products, such as Carbopack F, Carbopack C, Carbopack Y, Carbopack B, Carbopack X, etc.; coconut shell activated carbon; Petroleum activated carbon; or its analogues. The porous polymer may include, but is not limited to, for example: Tenax TA, Tenax GR; Porapak N; Chromosorb 106; Hayesep D; glass beads; silica gel; or the like.

According to a preferred embodiment of the present invention, the adsorption element 20 can be an activated carbon adsorption screen.

According to a preferred embodiment of the present invention, the adsorption element 20 can be a composite activated carbon adsorption screen.

The desorption unit 30 can include a second accommodating space 31 and a second heating element 32; wherein, the second accommodating space 31 can be used to place the adsorption element 20 for adsorbing the at least one aroma substance 51, and the second heating element The element 32 can be used to adjust the temperature of the adsorption element 20 that adsorbs the at least one fragrance substance 51 to desorb the at least one fragrance substance 51.

The analysis unit 40 can be used to analyze the at least one aroma substance 51.

According to an exemplary embodiment of the present invention, the sampling unit 10 may further include a rotating element 13 for adjustable rotation of the first accommodating space 11.

According to an embodiment of the present invention, the rotating element 13 can provide the first accommodating space 11 with a rotation speed greater than 0 rpm to 1000 rpm.

According to an embodiment of the present invention, the rotating element 13 can provide the first accommodating space 11 and the rotation speed can preferably be 100 rpm, 200 rpm, 250 rpm, 300 rpm, 350 rpm, 400 rpm, 450 rpm, 500 rpm, 550 rpm. rpm, 600 rpm, 650 rpm, 700 rpm, 750 rpm, 800 rpm, 900 rpm or 1000 rpm.

According to a preferred embodiment of the present invention, the rotating element 13 can provide the first accommodating space 11 with a rotation speed of 500 rpm.

According to an embodiment of the present invention, the rotating element 13 can cause the first accommodating space 11 to rotate intermittently.

According to the present invention, the intermittent rotation can be performed in a turn-stop manner. For example, turn for 1 second to 5 seconds, then stop for 1 second to 5 seconds, turn for 1 second to 5 seconds, and then stop for 1 second to 5 seconds, and repeat the turn-stop procedure within the first predetermined time.

According to an exemplary embodiment of the present invention, the sampling unit 10 may further include a blowing element 14 which can be used to deliver gas into the first accommodating space 11 to blow the dough sample 50.

According to the present invention, the gas delivered by the blowing element 14 may include hydrogen, nitrogen, helium, or a mixture thereof.

According to a preferred embodiment of the present invention, the gas may be helium.

According to the present invention, the blowing element 14 can be 50 mL/min~100 mL/min, 60 mL/min~100 mL/min, 70 mL/min~100 mL/min, 80 mL/min~100 mL/min, or Delivery of gas at a flow rate of 90 mL/min to 100 mL/min.

According to a preferred embodiment of the present invention, the predetermined flow rate may be 100 mL/min.

According to an exemplary embodiment of the present invention, the second heating element 32 can be used to gradually increase the temperature of the adsorption element 20 that adsorbs the at least one aroma substance to desorb the at least one aroma substance 51.

According to an exemplary embodiment of the present invention, the desorption unit 30 may further include a cooling element 33 that can be used to cool the desorbed at least one aroma substance 51.

According to an exemplary embodiment of the present invention, the second heating element 32 can be further used to raise the temperature of the at least one aroma substance 51 that has been reduced in temperature.

According to an exemplary embodiment of the present invention, the analysis unit 40 may include a gas chromatograph.

Preferably, the analysis unit 40 according to the present invention may further include a mass spectrometer. In other words, the analysis unit 40 can be a gas chromatography tandem mass spectrometer.

The following examples serve to illustrate the invention. These examples are in no way intended to limit the scope of the method and system.

Example 1

Prepare fermented dough Y. Take 0.1 g~0.2 g of fermented dough Y and put it into a 20-mL sample bottle as a dough sample; preheat the dough in the sample bottle at 80°C for 2 minutes, and at the same time, in batch mode ( For example, rotating for 1 second and stopping for 5 seconds, rotating for 5 seconds and stopping for 2 seconds, but not limited to this), rotating the sample bottle at a speed of 500 rpm to volatilize at least one aroma substance in the dough sample.

Insert the composite adsorbent tube containing activated carbon adsorption sieve B/activated carbon adsorption sieve X (carbopack ^TM B and carbopack ^TM X) into the preheated sample bottle for 30 minutes, and use helium at a flow rate of 100 mL/min Blow the dough sample to make the composite adsorption tube absorb at least one aroma substance in the dough sample at 80°C.

The adsorption tube that has completed the adsorption is clamped into the desorption unit, and the adsorption tube is raised in a gradient manner, so that the at least one aroma substance is desorbed from the adsorption tube. Please refer to FIG. 3, which is a temperature increase program of the desorption unit according to the embodiment of the present invention. The initial temperature of the desorption unit is set to 40°C, the temperature is increased to 300°C within 1 minute and maintained for 8 minutes, and the at least one aroma substance is desorbed from the adsorption tube by means of thermal desorption.

The desorbed at least one aroma substance is cooled to -40° C. with liquid nitrogen by using a cooling element, maintained for 30 seconds, and then heated to 280° C. at a heating rate of 12° C./second, to complete the extraction of the at least one aroma substance to be tested.

In a full sampling mode, the aforementioned extracted at least one aroma substance to be tested is analyzed by a gas chromatograph tandem mass spectrometer. The setting conditions of the gas chromatograph and mass spectrometer are as follows.

Setting conditions of gas chromatograph

1. Sample injection port conditions: set to full injection (splitless), injection temperature is 280℃, injection pressure is 7.3614 psi (pounds per square inch), flow rate is 24 mL/min, and the injection is 5 minutes Then blow off the residual sample at a rate of 20 mL/min.

2. Column conditions: Use Agilent HP 5MS column (length 30 m/inner diameter 250 μm/film thickness 0.25 μM), initial velocity in the column is 1.5 mL/min, and column pressure is 12.675 psi.

3. Oven conditions: The heating program of the oven is shown in Figure 4. It can be seen from FIG. 4 that the separation process of gas chromatography in this embodiment is to increase the temperature of the column in stages to separate at least one aroma substance to be measured. First, the initial temperature was maintained at 40°C for 2 minutes. Next, the temperature rises to 220°C at a temperature increase rate of 5°C/min, the rise time is 36 minutes, and the temperature is maintained at 220°C for 5 minutes. Then, the temperature was raised to 280°C at a temperature increase rate of 15°C/min, the rise time was 4 minutes, and the temperature was maintained at 280°C for 5 minutes.

Setting conditions of the mass spectrometer

1. Sampling: At least one aroma substance separated into the ion source of the mass spectrometer via the end of the gas chromatograph column. Among them, the temperature of the connecting channel from the column to the ion source is set to 280℃;

2. Sample ionization: EI (electron ionization) is used to ionize at least one aroma substance with a voltage of 70 volts, and the temperature of the ion source is controlled at 230°C.

3. Collect and detect samples: Use a quadrupole mass analyzer to screen ion fragments with a mass-to-charge ratio (m/z) ranging from 31 to 450, and detect them with a detector. The temperature is set to 150°C. This case uses NIST11 and WILEY275 databases for comparison

The resulting total ion chromatogram is shown in Figure 5. Among them, the compounds represented by the interpretable peaks in the total ion chromatogram are shown in Figure 5. The present invention uses NIST11 and WILEY275 mass spectrometry database to compare the compounds represented by each chromatographic peak.

It can be found that the identifiable peaks in the total ion chromatogram obtained in Example 1 include ethanol, diacetyl, acetyl acetate, acetic acid, and pentanol ( amyl alcohol, isoamyl alcohol, 2,3-butanediol, hexanol, isoamyl acetate, phenethyl alcohol.

Example 2

Prepare fermented dough L, take 0.1 g~0.2 g of fermented dough L, and put it as a dough sample into a 20-mL sample bottle; preheat the dough in the sample bottle at 80°C for 2 minutes, and at the same time, in batch mode ( For example, rotating for 1 second and stopping for 5 seconds, rotating for 5 seconds and stopping for 2 seconds, but not limited to this), rotating the sample bottle at a speed of 500 rpm to volatilize at least one aroma substance in the dough sample.

Insert the composite adsorbent tube containing activated carbon adsorption sieve B/activated carbon adsorption sieve X (carbopack ^TM B and carbopack ^TM X) into the preheated sample bottle for 30 minutes, and use helium at a flow rate of 100 mL/min Blow the dough sample to make the composite adsorption tube absorb at least one aroma substance in the dough sample at 80°C.

The adsorption tube that has completed the adsorption is clamped into the desorption unit, and the adsorption tube is raised in a gradient manner, so that the at least one aroma substance is desorbed from the adsorption tube. Please refer to FIG. 3, which is a temperature increase program of the desorption unit according to the embodiment of the present invention. The initial temperature of the desorption unit is set to 40°C, the temperature is increased to 300°C within 1 minute and maintained for 8 minutes, and the at least one aroma substance is desorbed from the adsorption tube by means of thermal desorption.

The desorbed at least one aroma substance is cooled to -40° C. with liquid nitrogen by using a cooling element, maintained for 30 seconds, and then heated to 280° C. at a heating rate of 12° C./second, to complete the extraction of the at least one aroma substance to be tested.

In a full sampling mode, the aforementioned extracted at least one aroma substance to be tested is analyzed by a gas chromatograph tandem mass spectrometer. The setting conditions of the gas chromatograph and mass spectrometer are as in Example 1.

The resulting total ion chromatogram is shown in Figure 6. Among them, the compounds represented by the interpretable chromatographic peaks in the total ion chromatogram are shown in Figure 6. The present invention uses NIST11 and WILEY275 mass spectrometry database to compare the compounds represented by each chromatographic peak.

It can be found that the identifiable chromatographic peaks in the total ion chromatogram obtained in Example 2 include ethanol, butanedione, ethyl acetate, acetic acid, pentanol, isoamyl alcohol, 2,3-butanediol, and hexanol. , Benzaldehyde, phenethyl alcohol.

It can be seen from the embodiments of the present invention that the analysis method provided by the present invention can not only effectively extract a variety of aroma substances from the dough, but also the resolution of the obtained results is good. From Table 1 below, it can be seen that the aroma substances obtained according to the analysis method of this embodiment do have multiple odors, which are also in line with the multi-layered flavor presented by the fermented dough products.

Table 1. Aroma substances and their corresponding aromas measured by the analytical method provided by the present invention. Among them, the FEMA number and aroma description are extracted from the website of the American Food Flavor and Extract Manufacturers Association. Aroma substance FEMA number Aroma description Diacetyl 2370 Butter, Pastry, Yeast Ethyl acetate 2414 Aromatic, Brandy, Contact Glue, Grape Acetic acid 2006 Acid, Fruit, Pungent, Sour, Vinegar Isoamyl alcohol 2057 Burnt, Cocoa, Floral, Malt Amyl alcohol 2056 Balsamic, Fruit, Green, Pungent, Yeast 2,3 butanediol - Creamy, Buttery (weak flavor) Hexanal 2567 Banana, Flower, Grass, Herb Isoamyl acetate 2055 Apple, Banana, Glue, Pear Benzaldehyde 2127 Bitter Almond, Burnt Sugar, Cherry, Malt, Roasted Pepper Phenethyl alcohol 2858 Fruit, Honey, Lilac, Rose, Wine

Comparative example 1

Prepare fermented dough Y. Take 0.5 g~1 g of fermented dough Y and put it into a 20-mL sample bottle as a dough sample; preheat the dough in the sample bottle at 85°C for 20 minutes to make at least An aroma substance evaporates.

Insert the adsorption probe containing the divinylbenzene/activated carbon adsorption sieve/polydimethylsiloxane (DVB/CAR/PDMS) composite fiber into the preheated sample bottle, and expose the composite fiber to In the at least one aroma substance for 20 minutes, the composite fiber can absorb the at least one aroma substance produced by the dough at 85°C.

In the full sampling mode, the composite fiber adsorbing at least one aroma substance to be measured is directly injected into the sample injection port of the gas chromatograph, and at least one aroma substance is self-composited by the temperature of the gas chromatograph's injection port. The fibers are desorbed and analyzed by gas chromatograph tandem mass spectrometer. The setting conditions of the gas chromatograph and mass spectrometer are as follows.

Setting conditions of gas chromatograph

1. Sample injection port conditions: set to full injection (splitless), injection temperature at 250°C, injection pressure at 7.3614 psi, flow rate at 24 mL/min, and 20 mL/min after injection for 5 minutes Blow away the residual sample at a rate of high.

2. Column conditions: use Agilent HP 5MS column (length 30 m/inner diameter 250 μm/film thickness 0.25 μM), initial velocity in the column 1 mL/min, and column pressure 7.3614 psi.

3. Oven conditions: The heating program of the oven is shown in Figure 4. It can be seen from FIG. 4 that the separation process of the gas chromatography in this embodiment is to continuously or stepwisely increase the temperature of the pipe column to separate at least one aroma substance to be measured. Firstly, the initial temperature is 45°C and maintained for 2 minutes; secondly, the temperature is increased to 110°C at a heating rate of 2°C/min and maintained for 2 minutes; then, the temperature is increased to 170°C at a heating rate of 3°C/min and maintained for 10 minutes ; Next, the temperature is increased to 220°C at a temperature increase rate of 4°C/min and maintained for 10 minutes; finally, the temperature is increased to 300°C and maintained for 2 minutes.

The setting conditions of the mass spectrometer are as in Example 1.

The resulting total ion chromatogram is shown in Figure 7. Among them, the compounds represented by the interpretable chromatographic peaks in the total ion chromatogram are shown in Figure 7. The present invention uses NIST11 and WILEY275 mass spectrometry database to compare the compounds represented by each chromatographic peak.

Comparative example 2

Prepare fermented dough L, take 0.5 g~1 g of fermented dough L, and put it into a 20-mL sample bottle as a dough sample; preheat the dough in the sample bottle at 85°C for 20 minutes to make at least the dough in the sample An aroma substance evaporates.

Insert the adsorption probe containing the divinylbenzene/activated carbon adsorption sieve/polydimethylsiloxane (DVB/CAR/PDMS) composite fiber into the preheated sample bottle, and expose the composite fiber to In the at least one aroma substance for 20 minutes, the composite fiber can absorb the at least one aroma substance produced by the dough at 85°C.

In the full sampling mode, the composite fiber adsorbing at least one aroma substance to be measured is directly injected into the sample injection port of the gas chromatograph, and at least one aroma substance is self-composited by the temperature of the gas chromatograph's injection port. The fibers are desorbed and analyzed by gas chromatograph tandem mass spectrometer. The setting conditions of the gas chromatograph are as in Comparative Example 1, and the setting conditions of the mass spectrometer are as in Example 1.

The resulting total ion chromatogram is shown in Figure 8. Among them, the compounds represented by the interpretable chromatographic peaks in the total ion chromatogram are shown in Figure 8. The present invention uses NIST11 and WILEY275 mass spectrometry database to compare the compounds represented by each chromatographic peak.

Please refer to FIG. 5 and FIG. 7, which are respectively analyzing the total ion chromatogram of the fermented dough Y using the method provided by the embodiment of the present invention and the method of the comparative example. It can be found that the identifiable peaks in the total ion chromatogram obtained in Example 1 include ethanol, butanedione, ethyl acetate, acetic acid, pentanol, isoamyl alcohol, 2,3-butanediol, and hexanol. , Isoamyl acetate, phenethyl alcohol; In contrast, the total ion chromatogram obtained in Comparative Example 1 can only distinguish 5 compounds, including ethanol, ethyl acetate, isoamyl alcohol, hexanol, and phenethyl alcohol.

Please refer to FIGS. 6 and 8 again, which are respectively analyzing the total ion chromatogram of the fermented dough L using the method provided in the embodiment of the present invention and the method of the comparative example. The identifiable chromatographic peaks in the total ion chromatogram obtained in Example 2 include ethanol, diacetyl, ethyl acetate, acetic acid, pentanol, isoamyl alcohol, 2,3-butanediol, hexanol, and benzaldehyde , Phenylethanol; In contrast, the total ion chromatogram obtained in Comparative Example 2 can only distinguish 4 compounds, including ethanol, ethyl acetate, isoamyl alcohol, and phenethyl alcohol.

Since the concentration of aroma substances contained in the dough is relatively low, in conventional methods, pretreatment or a large number of samples are often used to increase the concentration of the substance to be tested. Pre-processing the sample, such as extracting the substance to be tested in the sample with a solvent; or, as in the comparative example, using a larger amount of sample to absorb a larger amount of aroma substances contained in it. However, no matter what method is used, it may result in a large amount of water or solvent in the material to be tested. Too much water or solvent will seriously interfere with the gas chromatography method, and it is also easy for the material to be tested to be injected into the gas chromatograph. When the mouth is vaporized, the pressure is too high and abnormal. Compared with the prior art, the analysis method provided by the present invention only requires a small amount of dough samples, and the dough samples do not require pre-processing extraction steps, thus improving the efficiency of analysis and improving the resolution and accuracy of the analysis results.

The analytical methods used in Comparative Examples 1 and 2 have poor resolution, as shown in Figures 7 and 8, where it can be found that the chromatographic peaks of ethanol are extremely large, so that the chromatographic peaks of ethanol may overlap with the chromatographic peaks of other substances. Therefore, the number of compounds that can be identified in the total ion chromatogram spectrum is limited, and the aroma substances in the dough cannot be accurately analyzed.

In addition, the activated carbon adsorption sieve used in this case has a low affinity for water and methanol; it _{has a better affinity for organic compounds with short carbon chains (C 4} ~C ₁₂ ), which is suitable for flavor substances in fermented dough. For example: acid, aldehyde, diacetyl, etc.

Compared with the prior art, the dough flavor analysis method and the system provided by the present invention have high sensitivity and high resolution, and only need a small amount of dough without solvent extraction to detect a variety of aroma substances contained therein. The dough flavor analysis method and its system provided by the present invention can avoid solvent interference analysis results, and can improve the separation of test substances, reduce the overlap of the chromatographic peaks of each test aroma substance, and it is an analysis with high efficiency and good resolution. method.

S10~S50: steps 10: Sampling unit 11: The first housing space 12: The first heating element 13: Rotating element 14: Blowing element 20: Adsorption component 30: Desorption unit 31: The second accommodating space 32: The second heating element 33: cooling element 40: Analysis unit 50: Dough sample 51: Aroma substances

Fig. 1 is a flowchart of a dough flavor analysis method according to an exemplary embodiment of the present invention.

Fig. 2 is a schematic diagram of a dough flavor analysis system according to an exemplary embodiment of the present invention.

Fig. 3 is a temperature rise program of the desorption unit in the embodiment of the present invention.

FIG. 4 is a temperature rise program of the second temperature rise element of the analysis unit in the embodiment of the present invention.

Figure 5 is a total ion chromatogram obtained by the analysis method provided in Example 1 of the present invention.

Figure 6 is a total ion chromatogram obtained by the analysis method provided in Example 2 of the present invention.

Figure 7 is a total ion chromatogram obtained by the analytical method provided in Comparative Example 1.

FIG. 8 is a total ion chromatogram obtained by the analysis method provided in Comparative Example 2. FIG.

S10~S50: steps

Claims (17)

A method for analyzing the flavor of dough, comprising: placing a dough sample in a closed container; wherein the weight of the dough sample is less than 0.5 g; preheating the dough sample to generate at least one aroma substance; placing an adsorption element in the closed container The second predetermined time, wherein the adsorption element is a composite activated carbon adsorption sieve; during the second predetermined time, the dough sample is blown with a predetermined flow rate of gas to make the adsorption element contact and adsorb the at least one aroma substance; The adsorption element for adsorbing the at least one aroma substance so that the at least one aroma substance is desorbed from the adsorption element; and the desorbed at least one aroma substance is analyzed by gas chromatography. The method for analyzing the flavor of the dough as described in item 1 of the patent application, wherein the preparation method of the dough sample includes: preparing the dough; and directly taking the portion of the dough less than 0.5g, wherein the portion less than 0.5g is the dough sample. The dough flavor analysis method as described in item 1 of the scope of patent application, wherein the weight of the dough sample is not more than 0.3g. The method for analyzing the flavor of dough according to claim 1, wherein the step of preheating the dough sample includes: preheating the dough sample for a first predetermined time; and making the airtight container within the first predetermined time Rotate to produce at least one aroma substance. The method for analyzing the flavor of the dough as described in item 4 of the scope of patent application, wherein the step of rotating the airtight container within the first predetermined time to generate at least one aroma substance includes: making the airtight container be at the first predetermined time Rotate intermittently within time to produce at least one aroma substance. According to the method for analyzing the flavor of dough described in item 4 of the scope of patent application, the rotation speed of the airtight container is greater than 0rpm~1000rpm. According to the method for analyzing the flavor of dough as described in item 1 of the scope of patent application, the first predetermined time is less than 5 minutes. The method for analyzing the flavor of the dough as described in claim 1, wherein the step of raising the temperature of the adsorption element for adsorbing the at least one aroma substance so that the at least one aroma substance is desorbed from the adsorption element includes: Three predetermined time, the adsorption element adsorbing the at least one fragrance substance is heated in a gradient manner, so that the at least one fragrance substance is desorbed from the adsorption element. According to the method for analyzing the flavor of dough as described in item 8 of the scope of patent application, the gradient heating includes raising the temperature of the adsorption element for adsorbing the at least one aroma substance by at least 250° C. within 1 minute. The method for analyzing the flavor of the dough as described in item 8 of the scope of patent application, wherein the step of raising the temperature of the adsorption element for adsorbing the at least one aroma substance so that the at least one aroma substance is desorbed from the adsorption element further comprises: cooling the adsorption element At least one aroma substance desorbed from the adsorption element. The method for analyzing the flavor of the dough as described in claim 1, wherein the step of analyzing the desorbed at least one aroma substance by gas chromatography includes: heating the desorbed at least one aroma substance to a predetermined temperature; And analyzing the at least one aroma substance heated to the predetermined temperature by gas chromatography. A dough flavor analysis system is used to implement the dough flavor analysis method as described in any one of items 1 to 11 in the scope of the patent application. The analysis system includes: a sampling unit, including a first accommodating space, and a first temperature rise Element and blowing element; wherein, the first accommodating space is used to place a dough sample, the first heating element is used to adjust the temperature of the dough sample to generate at least one aroma substance, and the blowing unit is used to convey Gas into the first accommodating space to blow the dough sample; an adsorption element is placed in the first accommodating space for contacting and adsorbing the at least one aroma substance, wherein the adsorption element is a composite activated carbon adsorption sieve The desorption unit includes a second accommodating space and a second heating element; wherein the second accommodating space is used to place the adsorption element for adsorbing the at least one aroma substance, and the second heating element is used to adjust the The temperature of the adsorption element that adsorbs the at least one aroma substance to desorb the at least one aroma substance; and the analysis unit is used to analyze the at least one aroma substance. The dough flavor analysis system described in item 12 of the scope of patent application, wherein the sampling unit further includes a rotating element for adjusting the rotation of the first accommodating space. The dough flavor analysis system described in claim 12, wherein the second heating element is used to gradually increase the temperature of the adsorption element for adsorbing the at least one aroma substance to make the at least one aroma substance Desorption. The dough flavor analysis system described in item 14 of the scope of patent application, wherein the desorption unit further includes a cooling element for cooling the desorbed at least one aroma substance. The dough flavor analysis system described in claim 15, wherein the second heating element is multiplexed to increase the temperature of the at least one aroma substance that has been cooled. The dough flavor analysis system described in item 12 of the scope of patent application, wherein the analysis unit includes a gas chromatograph.

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