JP2002243695A - Aftertaste inspection method and aftertaste inspection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately and efficiently grasp the intensity of aftertaste. SOLUTION: A first film potential Va of a molecular film, which is formed from a mixture of a polymeric material, lipid and a plasticizer and has a prescribed thickness, obtained when the molecular film is immersed in a standard liquid and the second film potential Vb of the molecular film obtained, when the molecular film is immersed in a sample liquid are calculated; and thereafter, the molecular film is preliminarily cleaned with a cleaning liquid and the preliminary cleaned molecular film is immersed in the standard liquid to calculate third film potential Vc and the molecular film is further cleaned completely with the cleaning liquid. A series of these treatments are performed, with respect to a plurality of sample liquids different in aftertaste, the difference between the first and second film potentials obtained with respect to one sample liquid is set to a first response value Vs, and the difference between the first and third film potentials is set to a second response value Vr and data relating the ratio R of two response values, with the intensity of the actual aftertaste of each sample liquid being calculated. Similar treatment is applied to a liquid to be measured, to calculate the ratio, and the intensity of the aftertaste of the liquid to be measured is calculated, on the basis of the ratio and the data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for accurately and efficiently grasping the intensity of the aftertaste of foods and drinks, oral medicines and the like.

[0002]

2. Description of the Related Art The taste of foods, drinks, orally-administered medicines includes the taste when it is contained in the mouth and the taste after swallowing (aftertaste). , And those with a weak aftertaste are described as "having sharpness", which is a selling point when selling products.

[0003] For this reason, in a factory that actually manufactures beverages such as beer, when inspecting the manufactured beverage, a person who has undergone a sensory test, that is, a person who has been trained in taste evaluation called a paneler, is actually required. He drinks beverages and examines the strength of the aftertaste.

[0004]

However, the evaluation by the sensory test varies depending on the individual differences and physical condition of the panelists, and it is not possible to accurately grasp the subtle differences in the intensity of the aftertaste, and the reproducibility is low. High inspection cannot be performed.

[0005] In addition, when an object to be tested is an alcoholic beverage such as beer or a medicine, the amount that can be tested for the health of panelists is limited, and there is a problem that an efficient test cannot be performed.

An object of the present invention is to solve these problems and to provide a aftertaste inspection method and an aftertaste inspection device capable of accurately grasping the intensity of the aftertaste.

[0007]

According to a first aspect of the present invention, there is provided a method for detecting aftertaste, comprising mixing a polymer material, a lipid, and a plasticizer, forming the mixture in a predetermined thickness. Determining the response values of a plurality of sample solutions having different aftertaste intensities by using a molecular membrane whose membrane potential changes in response to the substance, and determining the response values and the actual aftertaste of each of the sample solutions. The step of obtaining information relating the strength of the, the step of obtaining the response value of the unknown liquid to be measured, the intensity of the aftertaste using the molecular film, and the response value of the molecular film to the liquid to be measured and the information Determining the intensity of the aftertaste of the liquid to be measured based on

According to a second aspect of the present invention, there is provided a method for detecting aftertaste, wherein a polymer material, a lipid and a plasticizer are mixed to form a predetermined thickness, and the membrane potential changes in response to a substance in a liquid. Immersing the membrane in a reference solution to determine a first membrane potential of the molecular membrane; and immersing the molecular membrane in the reference solution in one of a plurality of sample solutions having different intensities. Obtaining a second membrane potential of the molecular film, immersing the molecular film immersed in one of the sample liquids in a cleaning liquid for pre-cleaning, and immersing the pre-cleaned molecular film in the reference liquid. The steps of obtaining a third membrane potential of the molecular film, immersing the molecular film in the cleaning solution and completely cleaning the same, and repeating all the above-described steps for all of the plurality of sample liquids are repeated. A first membrane potential of the molecular membrane with respect to each sample solution; Determining a potential and a third membrane potential; and determining a difference between the first membrane potential and the second membrane potential obtained for one sample solution as a first response value, The difference between the potential and the third membrane potential is defined as a second response value, and the first and second molecular membranes with respect to the plurality of sample liquids are used.
A step of obtaining a second response value, and a step of obtaining a ratio between the first response value and the second response value obtained for each of the sample liquids as a value corresponding to the aftertaste strength of each sample liquid. Obtaining information relating the ratio of the obtained response values to the actual aftertaste strength of each sample liquid; and immersing the molecular film in the reference liquid to obtain a fourth membrane potential of the molecular film. And the step of determining the fifth membrane potential of the molecular membrane, by immersing the molecular membrane immersed in the reference liquid, and then immersing the molecular membrane in a measurement target liquid having an unknown taste intensity, Immersing the immersed molecular film in the first cleaning solution to perform pre-cleaning; immersing the pre-cleaned molecular film in the reference solution to obtain a sixth membrane potential of the molecular film; The difference between the membrane potential of No. 4 and the fifth membrane potential is referred to as a third response value, The difference between the potential and the membrane potential of the sixth to 4
Determining the ratio of the third response value to the fourth response value as a value corresponding to the intensity of the aftertaste of the liquid to be measured. Obtaining the strength of the aftertaste of the liquid to be measured based on the obtained ratio of the response values and the information.

According to a third aspect of the present invention, there is provided an aftertaste testing apparatus, wherein a polymer material, a lipid and a plasticizer are mixed to form a predetermined thickness, and the membrane potential changes in response to a substance in a liquid. A membrane, reference potential storage means for storing a membrane potential when the molecular film is immersed in a reference solution as a reference potential, and a membrane potential and the reference potential when the molecular film is transferred from the reference solution to the solution to be measured. A first response value detecting means for detecting a difference between the molecular film and the membrane liquid when the molecular film is transferred from the liquid to be measured to a cleaning liquid, preliminarily cleaned, and immersed in the reference liquid, and Second response value detection means for detecting a difference from a reference potential as a second response value, and a ratio between the first response value and the second response value corresponding to the aftertaste intensity of the liquid to be measured. A response ratio calculating means for calculating the value as a value; It was based on the ratio of the response value, and a aftertaste detecting means for determining the strength of aftertaste liquid to be measured.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows the configuration of an inspection system used in the taste inspection method of the present invention.

The inspection system includes a container 11 for storing a reference solution, a sample solution, a cleaning solution, or the like, and a reference electrode 1.
2. The molecular membrane sensor 15, a voltage detector 20 for detecting the membrane potential of the molecular membrane sensor 15 with reference to the potential of the reference electrode 12, and an A / D converter for converting the output of the voltage detector 20 into a digital value. 22, an arithmetic unit 23 for performing processing such as an arithmetic operation on the output of the A / D converter 22, and an output unit 24 for outputting the processing result of the arithmetic unit 23.

The surface of the reference electrode 12 is made of potassium chloride 10
It is covered with a buffer layer 13 obtained by solidifying 0 mM with agar, and is connected to a voltage detector 20 by a lead wire 12a.

In the molecular film sensor 15, a molecular film 17 is fixed on the surface of a base material 16 made of acrylic or the like, and a buffer layer 18 identical to the buffer layer 13 of the reference electrode 12 is provided on the opposite surface of the molecular film 17. An electrode 19 is provided via the electrode 19, and the electrode 19 is connected to the voltage detector 20 by a lead wire 15a.

The molecular film 17 is made of PVC (polyvinyl chloride).
Is mixed in a predetermined ratio of THF (tetrahydrofuran) at a temperature of about 30 ° C. in a flat-bottomed container (for example, an 85 mmφ petri dish). A 200 μm-thick film obtained by heating the mixture for 2 hours to evaporate THF is used, and has a characteristic that when immersed in a liquid, the membrane potential changes in response to a substance in the liquid. are doing.

It has been confirmed that the responsiveness of the molecular film 17 varies greatly depending on the material and mixing ratio of lipids and plasticizers.

That is, there are a lipid having a positive charge and a lipid having a negative charge. As the lipid having a positive charge, as shown in the following Table 1, primary amines, Alkylamines composed of secondary amines, tertiary amines and quaternary ammonium salts, quaternary phosphonium salts and the like can be used.

[0017]

[Table 1]

As the plasticizer to be combined with these positively charged lipids, phthalate esters, fatty acid esters, and phosphate esters shown in Table 2 below can be used.

[0019]

[Table 2]

The applicant of the present invention selects the content of the above-mentioned positively charged lipid to obtain a tannic acid type or iso α-type.
It has been experimentally confirmed that a molecular membrane exhibiting a very remarkable selectivity against an astringent taste, a bitter taste, and an astringent taste due to an acid-based substance can be obtained.

That is, for 800 mg of the polymer PVC, trioctylmethylammonium chloride as a lipid is added.
(TOMA) or tetradodecyl ammonium bromide
By examining the response to astringent substances and bitter substances by varying the content of (TDDA), the polymer material PVC
For 800 mg, a positively charged lipid is 0.0%
The result that the molecular film contained in the range of 005 to 0.69 mmol (mmol) shows a very remarkable selective response to astringency, bitterness, and astringency due to tannic acid-based or iso-α-acid-based substances. Could be obtained.

The tannic acid type or iso-α acid type substance is
Has a negative charge. From this, it is considered that the present invention is also effective for other strongly-charged substances having astringency, bitterness, and astringency having a negative charge.

In the following description, astringency, including astringency, bitterness or astringency due to tannin-based substances, will be referred to as astringency, and astringency, bitterness, or astringency due to iso-α-acid-based substances will be referred to as bitterness. .

FIG. 2 shows that the lipid (TO) of the molecular membrane was obtained under the conditions of 800 mg of the polymer PVC and 1000 μl of the plasticizer DOPP.
3 shows the response (CPA value) to each sample solution when the concentration of MA) was changed. The measurement results are obtained by averaging the CPA values obtained by performing the CPA measurement described below a plurality of times under the same conditions for each sample solution described below.

From the measurement results shown in FIG. 2, the lipid content was 0.0005 mmol to 800 mg for the polymer material.
In the range A of 0.69 mmol, extremely responsivity was exhibited for the sample solutions of astringent taste (tannic acid) and bitter taste (iso-α-acid), and the response to other sample solutions other than these was almost obtained. It can be seen that it has selective response to astringency and bitterness.

Also, astringency (tannic acid) and bitterness (iso α)
Paying attention to (acid), the peaks of the characteristics for bitterness and astringency are shifted, indicating that there is a difference in the response to the lipid content.

That is, the lipid content is about 800 m
In the range A1 of 0.017 mmol to 0.69 mmol with respect to g, the response of the astringent taste is more than twice as large as the response of the bitter taste.

Therefore, with a molecular membrane in which the lipid content is set in this range A1, even in a sample in which bitterness and astringency are mixed, only the astringency can be selectively detected.

Further, looking more closely within this range A1, the lipid content is 0.026 mmol to 0.58 mm.
In the range A1a of ol, a response three times or more of bitterness was obtained, and the lipid content was 0.036 mmol to 0.41 mm.
In the ol range A1b, a response five times or more the bitterness was obtained, and the selectivity for astringency was increased.

Therefore, the molecular membrane in which the lipid content is set in this range A1 can be used as a molecular membrane dedicated to testing for astringency.

The lipid content is about 800 m
0.0023 mmol to 0.017 mmol per g
In the range A2, the responses of the astringency and the bitterness are close to each other. Therefore, the molecular membrane in which the lipid content is set in this range A2 shows extremely high responsiveness common to astringency and bitterness, and can be used as a highly sensitive molecular membrane common to astringency and bitterness. .

The lipid content is 0.0005 mmol
In the range A3 of 1 to 0.0023 mmol, the magnitudes of the bitterness and astringency responses are reversed, and the bitterness response is at least twice as large as the astringency. Therefore, the molecular membrane in which the lipid content is set in this range A3 shows extremely high response only to bitterness (iso-α-acid), and even in a sample in which bitterness and astringency are mixed, only the bitterness can be selectively selected. And can be used as a molecular film exclusively for bitterness of beer or the like.

FIG. 3 shows an example of the response characteristics of the molecular film 17 of the molecular film sensor. As described above, the molecular film 17 is made of a polymer material PVC80 in order to examine the aftertaste of beer.
0 mg, lipid TDDA 0.572 mg (0.0
00 mmol) and 1 ml of a plasticizer DOPP. The molecular film 17 was used to form a sample solution of a sweet substance (sucrose) having a standard sweetness intensity and a standard sourness intensity. A sample liquid of a sour substance (tartaric acid) exhibiting a standard salty intensity, a sample liquid of a salty substance (NaCl) exhibiting a standard salty intensity, a bitter substance exhibiting a standard bitterness strength (quinine hydrochloride dihydrate, hereinafter quinine) ), A sample liquid of a bitter substance (iso-α-acid) having a standard bitterness, and a umami substance (L-
By performing CPA measurements on a sample solution of sodium hydrogen glutamate monohydrate (hereinafter, referred to as MSG) and a sample solution of astringent substance (tannic acid, hereinafter, referred to as tannin) having a standard astringency, FIG. Is obtained.

That is, in the inspection system shown in FIG. 1, the molecular film sensor 15 and the reference electrode 12 are immersed in the reference solution, and the membrane potential V1 (output value) of the molecular film 17 is measured and stored. After immersing the molecular membrane sensor 15 and the reference electrode 12 in one of the sample solutions, the molecular membrane sensor 15 and the reference electrode 12 are immersed in a reference solution, and the membrane potential V2 of the molecular membrane 17 is measured. A potential difference (referred to as CPA value) ΔV (= V2−V1) from the membrane potential V1 is obtained, and then a process of cleaning the molecular membrane sensor 15 and the reference electrode 12 is performed on all the sample solutions. It is.

As is apparent from FIG. 3, the sweetness (sucrose),
Acidity (tartaric acid), bitterness (quinine), umami (MSG),
Molecular membrane 1 for salty taste (NaCl) and astringency (tannin)
The response from the CPA measurement of 7 is almost negligible compared to the response to bitterness (iso-α-acid).

Therefore, by using the molecular film 17, it is possible to selectively inspect the bitterness of the iso-α-acid type, that is, the bitterness of beer or the like.

As the molecular film 17 of the molecular film sensor 15, a material obtained by mixing a lipid having a negative charge and a plasticizer in a predetermined ratio to a polymer material can be used.

The lipids having a negative charge include those shown in Table 3 below.

[0039]

[Table 3]

As a plasticizer to be combined with a lipid having a negative charge, there is a nitrobenzene type plasticizer shown in Table 4 below.

[0041]

[Table 4]

For example, the above-mentioned negative lipid dinormal decyl phosphate (2
C ₁₀ ) at a rate of about 100 mg and NPOE (nitrophenyl alkyl ether) at a rate of 1 ml, when using a molecular film 17 made of sweet (sucrose), sour (tartaric), salty (NaCl), bitterness (iso-α-acid), umami (MSG), and astringency (tannin) have been confirmed to be almost negligible in response to bitterness (quinine). The membrane can also be used to test the aftertaste of quinine-based bitter substances.

As described above, the molecular film 17 can have a characteristic of selectively responding to a specific substance exhibiting astringency or bitterness by appropriately selecting the materials and amounts of lipids and plasticizers. Here, in order to examine the aftertaste of beer, a molecular film that selectively responds to the above-mentioned iso-α-acid bitterness is used.

The membrane potential of the molecular film 17 depends on the reference electrode 12
The potential is detected by the voltage detector 20 with reference to the potential, and is input to the A / D converter 22, converted into a digital value, and input to the arithmetic unit 23.

The arithmetic unit 23 is constituted by a microcomputer including a memory 23 a, performs processing such as storage and operation with respect to the membrane potential of the molecular film 17, and outputs the processing result from the output unit 24.

Next, a method for testing the strength of the aftertaste of beer using this testing system will be described.

By using the molecular film 17 which selectively responds to the iso-α-acid-based substance as described above, the present inventors relate the response value of the molecular film 17 to beer and the actual aftertaste intensity. It was confirmed experimentally that attachment could be made.

The details of the experiment will be described below.
In this experiment, in addition to the sample liquids J (1) to J (M) of a plurality of brands of beer having different known taste intensities, as described below, components substantially equivalent to human saliva were used as described below. A reference solution serving as a reference for measurement with the addition of alcohol of the same concentration, and a washing solution prepared by removing the alcohol component from the reference solution and making the components almost equivalent to human saliva were prepared.

Reference solution: KCl 30 mM + tartaric acid 0.
3 mM + ethanol 5 vol percent Wash solution: KCl 30 mM + tartaric acid 0.3 mM

The measurement for the sample liquids J (1) to J (M) was performed according to the procedure shown in FIG.

That is, first, a variable m for designating a sample liquid
Is initialized to 1, the molecular membrane sensor 15 is immersed in the reference liquid R together with the reference electrode 12, and the membrane potential Va (m) of the molecular membrane 17 of the molecular membrane sensor 15 is detected and stored as the first membrane potential (S1). ~ S3).

Next, the molecular membrane sensor 15 is immersed in the sample liquid J (m) together with the reference electrode 12, and the membrane potential Vb (m) of the molecular membrane 17 of the molecular membrane sensor 15 is detected and stored as a second membrane potential. (S4, S5).

Then, a variable n indicating the number of times of pre-cleaning is set to 1
, The molecular film sensor 15 is immersed in the cleaning liquid together with the reference electrode 12 and lightly cleaned (preliminary cleaning), then returned to the reference liquid again, and the membrane potential Vcn (m) of the molecular film 17 of the molecular film sensor 15 is returned. Is detected and stored as the third membrane potential (S6 to S9).

Further, after repeating the pre-cleaning and the measurement of the reference liquid up to N times (for example, N = 5), the molecular film sensor 15 is immersed in the cleaning liquid together with the reference electrode 12 to be completely cleaned (S10). S12).

Hereinafter, the above-mentioned S
By repeating the processes of 2 to S12, the measurement for each sample solution is completed (S13, S14).

Next, each sample solution J
The first response value (relative value) and the second response value (CPA value) of the molecular film 17 for (1) to J (M) are obtained (S15).

Here, the relative value Vs (m) of the molecular film 17 with respect to the sample liquid J (m) is equal to the first membrane potential Va (m).
And the second membrane potential Vb (m), that is, Vs (m) = Vb (m) -Va (m).

The CPA value Vrn (m) of the sample film J (m) for each pre-cleaning of the molecular film 17 is calculated by calculating the difference between the first membrane potential Va (m) and the third membrane potential Vcn (m). That is, Vrn (m) = Vcn (m) -Va (m).

After the relative value of the molecular film 17 and the CPA value with respect to each sample solution are obtained as described above, the ratio of these two response values (hereinafter referred to as the response ratio), Rn (m) = Vrn ( m) / Vs (m) is determined as a value corresponding to the intensity of the aftertaste of each sample liquid (S16).

Next, information for associating the response ratio R (m) of each sample solution with the actual strength of the aftertaste is obtained and stored (S17).

This link will be described based on actual measurement results. FIGS. 5 to 9 show the response values obtained by actually performing the above-described processing on the sample liquids J (1) to J (10) described above for each sample liquid (two in each figure). FIG. 10 shows the response ratios of all the sample solutions so that they can be compared. In FIGS. 5 to 9, the numbers surrounded by squares represent each sample liquid J (1).
ＪJ (10) correspond to the numbers in parentheses.

As is clear from FIG. 10, the response ratio of each sample solution monotonously decreases as the number of times of pre-washing increases, and the response ratio of each sample solution obtained in the first pre-wash is large or small. It can be seen that the relationship is almost the same as the magnitude relationship of the response ratio obtained in the second and subsequent preliminary washings.

Since the difference between the response ratios of the sample solutions decreases as the number of times of the pre-wash increases, it is more advantageous to use the response ratio obtained in the first pre-wash for evaluating the strength of the aftertaste. I understand.

Therefore, suppose that the sample liquid J (5) (hereinafter referred to as sample liquid A) having the largest response ratio obtained in the first preliminary washing is used.
Is given an evaluation point 3 indicating that the aftertaste is strong, and an evaluation point 2 indicating that the sample liquid J (9) having a medium response ratio (hereinafter referred to as sample liquid B) has a moderate aftertaste.
To give a sample solution J (8) (hereinafter referred to as sample solution C) having a low response ratio, an evaluation point 1 indicating that the intensity of the aftertaste is small, and actually, these sample solutions A,
When sensory tests for B and C were performed by a total of 12 panelists, as shown in FIG. 11, the average of the sensory evaluation points of the sample liquid A was about 2.8, and the average of the sensory evaluation points of the sample liquid B was about 1.8, the average of the sensory evaluation points of the sample liquid C was about 1.3, and it was found that there was almost a correlation with the evaluation points determined by the magnitude of the response ratio.

Therefore, it is recognized that the response ratio R has a one-to-one relationship with the actual strength of the aftertaste, and by using the information of this association, the evaluation of the beer whose unknown aftertaste is unknown depends on the sensory test. Can be done without.

For this association, a comparison method using a threshold value or a calculation method can be considered. The comparison method using the threshold value is performed by comparing a response ratio R (m) of the liquid to be measured with a threshold value set in advance based on the response ratio of the sample liquid and the evaluation point obtained by the sensory test. Is roughly determined, for example, the response ratio R obtained by the first preliminary washing
When 1 (m) is 0.32 or more, the evaluation point 3 (the aftertaste intensity is large), and when the response ratio R1 (m) is in the range of 0.28 to 0.32, the evaluation point 2 (the aftertaste intensity is high). Medium), response ratio R
When 1 (m) is 0.28 or less, it is determined to be evaluation point 1 (the aftertaste strength is small).

Further, in the calculation method, a parameter (proportional coefficient, etc.) relating the response ratio obtained by the measurement of the sample liquid to the evaluation point of the sensory test is obtained in advance, and the response ratio of the liquid to be measured and the parameter are determined. Is a method of calculating an evaluation point indicating the strength of the aftertaste of the liquid to be measured by the calculation of

For example, the sensory evaluation point Q of each sample solution
The parameters α and β are determined so that (m) satisfies the following relationship. Q (m) = α · R1 (m) + β

Then, using the response ratio Rx obtained for the liquid to be measured and the parameters α and β, the intensity Qx of the aftertaste of the liquid to be measured is obtained by calculating Qx = α · Rx + β.

Regardless of the method used, the same measurement as described above is performed on the liquid to be measured whose aftertaste intensity is unknown.
Using the response ratio and information such as the threshold value and the parameter, it is possible to grasp the intensity of the aftertaste of the liquid to be measured.

When the intensity of the aftertaste of the liquid to be measured is to be inspected, the information obtained by the processing of FIG. 4 is stored in advance in, for example, the memory 23a of the arithmetic unit 23, and the information shown in FIG. As shown in the processes S18 to S28, the measurement with the molecular film 17 for the liquid X to be measured whose aftertaste is unknown is performed in the same manner as described above to obtain the fourth membrane potential Vd, the fifth membrane potential Ve, and the fifth membrane potential. The potential Vf is determined, the relative value Vs and the CPA value Vr are determined from these membrane potentials, and the aftertaste strength of the liquid X to be measured is determined from the response value ratio Rx and the information in the memory 23a.

If the strength of the aftertaste is determined in this way, even if the sensory test is not performed on the liquid to be measured,
The strength of the aftertaste of the liquid to be measured can be accurately grasped,
Inspections with high reproducibility can be efficiently performed without being influenced by individual differences or physical conditions of panelists.

Also, by preliminarily setting the program of the arithmetic unit 23 so that the processing shown in FIGS. 4 and 12 can be performed, it is possible to obtain information relating the response ratio to the intensity of the aftertaste, An inspection system capable of accurately and efficiently determining the intensity of the aftertaste of a liquid can be provided.

In the above description, in order to examine the aftertaste of beer, the molecular membrane 17 containing a positively charged lipid and selectively responding to iso-α-acid bitterness was used. Is not limited to beer, and as described above, the use of a molecular film that selectively responds to the taste of the test object can also be used to test the aftertaste of other beverages, oral medicines, and the like in the same manner as described above.

[0075]

As described above, according to the first aspect of the present invention,
The taste test method uses a molecular membrane that is formed to a predetermined thickness by mixing a polymer material, lipid and plasticizer, and changes the membrane potential in response to substances in the liquid, and the intensity of the aftertaste varies. Determining response values of a plurality of sample liquids, obtaining information relating the obtained response values and the actual aftertaste intensity of each sample liquid, and determining the aftertaste intensity using the molecular film. Determining a response value of the unknown liquid to be measured; and determining an aftertaste strength of the liquid to be measured based on the response value of the molecular film to the liquid to be measured and the information.

According to a second aspect of the present invention, there is provided a method for detecting aftertaste, wherein a polymer material, a lipid and a plasticizer are mixed to form a predetermined thickness, and a membrane potential changes in response to a substance in a liquid. Immersing the membrane in a reference solution to determine a first membrane potential of the molecular membrane; and immersing the molecular membrane in the reference solution in one of a plurality of sample solutions having different intensities. Obtaining a second membrane potential of the molecular film, immersing the molecular film immersed in one of the sample liquids in a cleaning liquid for pre-cleaning, and immersing the pre-cleaned molecular film in the reference liquid. The steps of obtaining a third membrane potential of the molecular film, immersing the molecular film in the cleaning solution and completely cleaning the same, and repeating all the above-described steps for all of the plurality of sample liquids are repeated. A first membrane potential of the molecular membrane with respect to each sample solution; Determining a potential and a third membrane potential; and determining a difference between the first membrane potential and the second membrane potential obtained for one sample solution as a first response value, The difference between the potential and the third membrane potential is defined as a second response value, and the first and second molecular membranes with respect to the plurality of sample liquids are used.
A step of obtaining a second response value, and a step of obtaining a ratio between the first response value and the second response value obtained for each of the sample liquids as a value corresponding to the aftertaste strength of each sample liquid. Obtaining information relating the ratio of the obtained response values to the actual aftertaste strength of each sample liquid; and immersing the molecular film in the reference liquid to obtain a fourth membrane potential of the molecular film. And the step of determining the fifth membrane potential of the molecular membrane, by immersing the molecular membrane immersed in the reference liquid, and then immersing the molecular membrane in a measurement target liquid having an unknown taste intensity, Immersing the immersed molecular film in the first cleaning solution to perform pre-cleaning; immersing the pre-cleaned molecular film in the reference solution to obtain a sixth membrane potential of the molecular film; The difference between the membrane potential of No. 4 and the fifth membrane potential is referred to as a third response value, The difference between the potential and the membrane potential of the sixth to 4
Determining the ratio of the third response value to the fourth response value as a value corresponding to the intensity of the aftertaste of the liquid to be measured. Obtaining the strength of the aftertaste of the liquid to be measured based on the obtained ratio of the response values and the information.

The aftertaste testing device according to the third aspect of the present invention is a molecule which is formed to a predetermined thickness by mixing a polymer material, a lipid and a plasticizer, and whose membrane potential changes in response to a substance in a liquid. A membrane, reference potential storage means for storing a membrane potential when the molecular film is immersed in a reference solution as a reference potential, and a membrane potential and the reference potential when the molecular film is transferred from the reference solution to the solution to be measured. A first response value detecting means for detecting a difference between the molecular film and the membrane liquid when the molecular film is transferred from the liquid to be measured to a cleaning liquid, preliminarily cleaned, and immersed in the reference liquid, and Second response value detection means for detecting a difference from a reference potential as a second response value, and a ratio between the first response value and the second response value corresponding to the aftertaste intensity of the liquid to be measured. A response ratio calculating means for calculating the value as a value; It was based on the ratio of the response value, and a aftertaste detecting means for determining the strength of aftertaste liquid to be measured.

Therefore, the intensity of the aftertaste of the liquid to be measured can be accurately and efficiently grasped without actually performing a sensory test.

[Brief description of the drawings]

FIG. 1 is a diagram showing an inspection system for performing an aftertaste inspection method according to an embodiment of the present invention.

FIG. 2 is a diagram showing a change in response characteristics of a molecular membrane with respect to lipid concentration.

FIG. 3 is a diagram showing response characteristics of a molecular film used in the taste inspection method according to the embodiment;

FIG. 4 is a flowchart showing a procedure of an aftertaste inspection method.

FIG. 5 is a diagram showing a response value of a molecular membrane to a sample solution.

FIG. 6 is a diagram showing a response value of a molecular film to a sample solution.

FIG. 7 is a diagram showing a response value of a molecular film to a sample solution.

FIG. 8 is a diagram showing a response value of a molecular film to a sample solution.

FIG. 9 is a diagram showing a response value of a molecular film to a sample solution.

FIG. 10 is a diagram showing a ratio of a response value of a molecular membrane to a sample solution.

FIG. 11 is a diagram showing a correlation between an evaluation point of aftertaste obtained by measurement and an evaluation point obtained by sensory test.

FIG. 12 is a flowchart showing a procedure of an inspection method for a liquid to be measured whose aftertaste is unknown.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Container 12 Reference electrode 13 Buffer layer 15 Molecular film sensor 16 Base material 17 Molecular film 18 Buffer layer 19 Electrode 20 Voltage detector 22 A / D converter 23 Arithmetic device 23a Memory 24 Output device

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Katsufumi Sato, Inventor, 5-10-27 Minamiazabu, Minato-ku, Tokyo Anritsu Corporation (72) Inventor Hidekazu Ikezaki 5-10-27, Minamiazabu, Minato-ku, Tokyo Anritsu (72) Inventor Yoshikazu Kobayashi F-term (reference) 2G045 AA40 CB30 DA80 FB05 GC19 JA01 JA07 4J002 AA001 BD041 EH097 EH146 EH147 EN026 EN136 ES007 EW046 EW047 FD027 GT00

Claims (3)

[Claims] 1. A method of mixing a polymer material, a lipid, and a plasticizer to a predetermined thickness and using a molecular membrane whose membrane potential changes in response to a substance in a liquid, and having different aftertaste strengths. Determining the response value of the sample liquid of the above; and obtaining information relating the obtained response value and the actual strength of the aftertaste of each sample liquid; and determining the strength of the aftertaste using the molecular film. Determining the response value of the liquid to be measured, and determining the aftertaste strength of the liquid to be measured based on the response value of the molecular film to the liquid to be measured and the information. 2. A molecular film, which is formed to a predetermined thickness by mixing a polymer material, a lipid and a plasticizer, and whose molecular potential changes in response to a substance in a liquid, is immersed in a reference liquid, and Determining a first membrane potential; and subsequently immersing the molecular membrane immersed in the reference solution in one of a plurality of sample solutions having different taste intensities to determine a second membrane potential of the molecular membrane Immersing the molecular film immersed in one of the sample solutions in a cleaning solution to perform pre-cleaning; immersing the pre-cleaned molecular film in the reference solution to increase the third membrane potential of the molecular film The step of obtaining, and the step of immersing the molecular film in the cleaning solution and completely cleaning the same; The steps described above are repeatedly performed on all of the plurality of sample solutions, and the first of the molecular film for each sample solution is performed. Determining membrane potential, second membrane potential, and third membrane potential The difference between the first membrane potential and the second membrane potential obtained for one sample solution is defined as a first response value, and the difference between the first membrane potential and the third membrane potential is determined. Obtaining a first response value and a second response value of the molecular film with respect to the plurality of sample solutions, respectively, as a second response value; and a first response value and a second response value obtained for each of the sample solutions. Determining the ratio of each of the sample solutions as a value corresponding to the intensity of the aftertaste, and obtaining information relating the ratio of the determined response value and the actual intensity of the aftertaste of each of the sample solutions, Immersing the molecular film in the reference liquid to determine a fourth membrane potential of the molecular film; and immersing the molecular film immersed in the reference liquid in a liquid to be measured whose taste intensity is unknown. Obtaining a fifth membrane potential of the molecular membrane; Immersing the sub-membrane in the first cleaning solution for pre-cleaning; immersing the pre-cleaned molecular film in the reference solution to obtain a sixth membrane potential of the molecular film; Determining the difference between the potential and the fifth membrane potential as a third response value, and determining the difference between the fourth and sixth membrane potentials as a fourth response value; and determining the determined third response. Determining a ratio of the response value to the fourth response value as a value corresponding to the intensity of the aftertaste of the liquid to be measured; and measuring the ratio based on the ratio of the response value obtained for the liquid to be measured and the information. Determining the strength of the aftertaste of the target liquid. 3. A molecular film which is formed to a predetermined thickness by mixing a polymer material, a lipid and a plasticizer, and changes a membrane potential in response to a substance in a liquid; and dipping the molecular film in a reference liquid. A reference potential storage means for storing the membrane potential at the time as a reference potential; and detecting a difference between the membrane potential and the reference potential when the molecular membrane is transferred from the reference solution to the measurement target solution as a first response value. A first response value detecting means, and a difference between a membrane potential when the molecular film is transferred from the liquid to be measured to a cleaning liquid and pre-washed and then immersed in the reference liquid and the reference potential as a second response value. Second response value detection means for detecting; response ratio calculation means for calculating a ratio of the first response value to the second response value as a value corresponding to the aftertaste strength of the liquid to be measured; Based on the ratio of the response values calculated by the value calculation means, Aftertaste inspection apparatus and a aftertaste detecting means for determining the strength of aftertaste.