JP2014018106A - Method for evaluating flavor of food products - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for evaluating the influence of degradation of an edible oil on the flavor of food products.SOLUTION: The method for evaluating the influence of degradation of the edible oil on the flavor of food products includes the steps of: (1) preparing polar solvent extracts of an evaluation target oil and an oil for comparison; (2) measuring the respective contents of volatile organic compounds in the polar solvent extracts; and (3) evaluating the influence on the flavor of food products by comparison of the content of the material in the evaluation target oil and the content of the material in the oil for comparison.

Description

  The present invention relates to a method for evaluating the flavor of food, and more particularly, to a method for evaluating the influence of food oil on the flavor of food.

Oils and fats are an important energy source for human survival and a source of essential fatty acids essential for living organisms. Edible fats and oils are widely used in the preparation and processing of foods and are indispensable for the current diet. In particular, deep-fried foods and fried foods are widely used not only in the home but also in the restaurant industry because they can provide high-volume food at low cost.
It is known that fats and oils are oxidized during heating and storage, and the quality deteriorates (see Patent Document 1, etc.). For this reason, foods cooked using deteriorated oils and fats have an unpleasant odor and taste, which may harm the health of those who have taken them.
In the Food Sanitation Law, the deterioration of fats and oils is evaluated by acid value, peroxide value, and the like. However, the acid value and peroxide value are physical properties of edible fats and oils, and it is not clear how much they affect the taste and smell of humans such as the taste and smell of edible fats and oils.

JP 2012-65657 A

  This invention makes it a main subject to provide the method of evaluating the influence on the flavor of the foodstuff by deterioration of edible fats and oils.

As a result of intensive studies, the present inventors have found that the flavor of foods using the edible fats and oils can be evaluated based on the content of volatile organic compounds in the polar solvent extract of the edible fats and oils. It came.
The present invention includes the following inventions.

[1] A method for evaluating the influence of food oil and fat on the flavor of food,
(1) A step of preparing a polar solvent extract of an evaluation object oil and a comparison object oil;
(2) A step of measuring the content of the volatile organic compound in the polar solvent extract, and (3) comparing the content of the substance in the evaluation target oil and fat with the content of the substance in the comparison target fat and oil. Process to evaluate the impact on the flavor of food,
Including methods.
[2] In the step (3), when the content of the volatile organic compound in the evaluation target oil or fat is greater than the content of the substance in the comparison target oil or fat, the taste of the food is evaluated as being impossible. the method of.
[3] The method according to any one of [1] or [2], wherein the volatile organic compound is one or more selected from aldehydes having 1 to 11 carbon atoms.
[4] The method according to any one of [1] to [3], wherein the volatile organic compound is acrolein and / or propanal.
[5] In the step (2), the volatile organic compound in the polar solvent extract is obtained by gas chromatography, liquid chromatography, mass spectrometry, a combination of gas chromatography and mass spectrometry, or a combination of liquid chromatography and mass spectrometry. The method according to any one of [1] to [4], wherein the content of each is measured.

  This invention can provide the method of evaluating the influence on the flavor of the foodstuff by deterioration of edible oil and fat. More specifically, based on the content of the volatile organic compound in the polar solvent extract of the edible oil and fat, the flavor of the food using the edible oil and fat can be evaluated.

It is a figure which shows content of the acrolein and propanal in the edible fats and oils of rapeseed oil (180 degreeC heating oil) and rice oil (180 degreeC heating oil). It is a figure which shows content of acrolein and propanal in the water extract of rapeseed oil (180 degreeC heating oil) and rice oil (180 degreeC heating oil). It is a figure which shows the measurement result of edible oil and fat and a water extract about rapeseed oil (180 degreeC heating oil). It is a figure which shows content of acrolein and propanal in edible oil and fat and water extract about rapeseed oil (180 degreeC heating oil).

The method for evaluating the influence on the flavor of food due to the deterioration of the edible fat of the present invention,
(1) A step of preparing a polar solvent extract of an evaluation object oil and a comparison object oil;
(2) A step of measuring the content of the volatile organic compound in the polar solvent extract, and (3) comparing the content of the substance in the evaluation target oil and fat with the content of the substance in the comparison target fat and oil. Process to evaluate the impact on the flavor of food,
As long as it contains.

  Edible fats and oils are known to deteriorate due to oxidation, hydrolysis and the like. Degradation of edible oils and fats occurs, for example, by reaction with air or water at room temperature or high temperature. The present inventors have found that volatile organic compounds are produced in edible oils and fats due to deterioration, and that such volatile organic compounds are extracted into saliva, water, ethanol, etc., and are perceived as flavor on the tongue. I found out. Based on this knowledge, if a polar solvent extract is prepared from the evaluation target fat and oil and the comparison target fat and oil, and the contents of the volatile organic compounds in the polar solvent extract are measured and compared with each other, the food due to the deterioration of the edible fat is obtained. It was found that the influence on the flavor of can be evaluated.

(Edible oils and fats)
The edible oils and fats used in the present invention are not particularly limited, for example, rice oil, rapeseed oil, soybean oil, palm oil, sesame oil, corn oil, cottonseed oil, coconut oil, olive oil, palm kernel oil, coconut oil, safflower oil, sunflower oil, Examples include almond oil, cashew oil, hazelnut oil, macadamia nut oil, beef tallow, lard, sheep fat, chicken oil, whale oil, whale brain oil, dolphin oil, liver oil, horse oil, fish oil and the like. The edible fat may be a mixed oil of two or more.
The contents of steps (1) to (3) will be described in detail below.

Step (1): Preparation of Polar Solvent Extract In this step, a polar solvent extract of the evaluation target oil and fat and the comparison target oil and fat is prepared using the polar solvent.

(Evaluation target oil and fat and comparison target oil and fat)
In this invention, evaluation object fats and oils show the edible fats and oils which evaluate the influence on the flavor of the foodstuff by deterioration of the said fats and oils. Moreover, in this invention, comparison object fats and oils show the edible fats and oils used as the reference | standard which compares the said evaluation object fats and oils and flavor. The evaluation target fats and oils and the evaluation target fats and oils are not particularly limited as long as they are the edible fats and oils.

(Polar solvent)
The polar solvent used in the present invention is not particularly limited, and may be an inorganic solvent or an organic solvent. Examples of the inorganic solvent include acidic aqueous solutions such as hydrochloric acid, sulfuric acid, nitric acid, carbonic acid, and phosphoric acid; basic aqueous solutions such as sodium hydroxide, magnesium hydroxide, calcium hydroxide, potassium hydroxide, and sodium hydrogen carbonate; water, saline Neutral aqueous solution; and the like. Examples of water include pure water, purified water, and distilled water. Examples of the organic solvent include alcohols such as methanol, ethanol, isopropyl alcohol, t-butyl alcohol, and t-amyl alcohol; ester compounds such as methyl acetate and ethyl acetate; ketones such as acetone and methyl ethyl ketone;
The polar solvent is preferably a neutral inorganic solvent or alcohol, more preferably water, methanol or ethanol, and particularly preferably water.
In the present invention, the “polar solvent” refers to a liquid composed of molecules having a large dipole moment.

(Preparation of polar solvent extract)
The method for preparing the polar solvent extract is not particularly limited, and can be performed by a known method. The polar solvent extract can be prepared by, for example, using a separatory funnel, a test tube with a stopper, a centrifuge tube, a beaker, and the like and thoroughly mixing the evaluation target oil or fat and the comparison target oil and fat with the polar solvent.
In the preparation of the polar solvent extract, the ratio of the evaluation target oil or fat or the comparison target oil and the polar solvent is not particularly limited, but the polar solvent is 0.01 to 100 parts by volume with respect to 1 part by volume of the evaluation target oil or fat. 0.05 to 50 parts by volume, preferably 0.1 to 30 parts by volume, particularly preferably 0.5 to 5 parts by volume.
In the preparation of the polar solvent extract, the temperature is not particularly limited, but may be, for example, -20 ° C to 80 ° C or less, preferably 0 ° C to 50 ° C, and more preferably 20 ° C to 40 ° C. When the temperature is in the above range, it is preferable because a new volatile organic compound is not generated during the preparation of the polar solvent extract.
It is preferable to prepare the polar solvent extract under the same conditions for the oil to be evaluated and the oil to be compared.

Step (2): Measurement of content of volatile organic compound in polar solvent extract In this step, the content of volatile organic compound in the polar solvent extract is measured.

(Volatile organic compounds)
The volatile organic compound in this invention should just be an organic compound which volatilizes easily in air | atmosphere at normal temperature normal pressure, and is not specifically limited. Examples of volatile organic compounds include aliphatic compounds such as hexane, 2,4-dimethylpentane, heptane, octane, nonane, decane, and undecane; aromatic compounds such as benzene, toluene, ethylbenzene, xylene, styrene, and trimethylbenzene. Compound: Organochlorine compounds such as chloroform, dichloroethane, trichloroethane, carbon tetrachloride, dichloropropane, trichloroethylene, tetrachloroethylene, chlorodibromomethane, paradichlorobenzene; perfluorodimethylcyclohexane, perfluoromethylcyclohexane, hexafluorobenzene, octafluorotoluene, Examples include perfluoroallylbenzene, ethyl acetate, butyl acetate, methyl ethyl ketone, methyl isobutyl ketone, butanol, pinene, and limonene. That.
Preferred examples of the volatile organic compound in the present invention include hydrocarbons having 20 or less carbon atoms, alcohols, ethers, aldehydes, and carboxylic acids, and these include S (sulfur), N (nitrogen), and P (phosphorus). It may be included. More preferably, it is an aldehyde, and among these, one or more selected from aldehydes having 1 to 11 carbon atoms are preferable, and one or more selected from aldehydes having 2 to 8 carbon atoms are more preferable. . Specific examples include acetaldehyde, propanal, acrolein, butanal, butenal, pentanal, pentenal, pentedienal, hexanal, hexenal, hexedienal, heptanal, heptenal, heptedenal, octanal, octenal, octedenal and the like. Particularly preferred are aldehydes having 2 to 3 carbon atoms such as acetaldehyde, propanal and acrolein. The volatile organic compound in the present invention is most preferably acrolein and / or propanal.

(Measuring method)
Although the measuring method of content of the volatile organic compound in a polar solvent extract is not specifically limited, For example, it can carry out with the following method.
That is, a standard solution of a volatile organic compound to be measured is prepared and subjected to instrumental analysis, a measured value is obtained, and a calibration curve is created. Then, the polar solvent extract is subjected to instrumental analysis in the same manner as the measurement of the standard solution, and the obtained measured value is applied to a calibration curve to obtain the content of the volatile organic compound in the polar solvent extract. it can. More specifically, for example, a method described in the specification of Japanese Patent Application No. 2012-13881 can be mentioned.

The standard solution for preparing a calibration curve is preferably prepared by dissolving a sample of a volatile organic compound to be measured in an oil having a linolenic acid content of 1.5% by mass or less. Examples of fats and oils having a linolenic acid content of 1.5% by mass or less include medium-chain fatty acid triglycerides (hereinafter sometimes abbreviated as “MCT”), olive oil, sesame oil, rice oil, safflower oil (hylinol), safflower oil, and the like. Examples include flower oil (high oleic), corn oil, palm oil, palm kernel oil, sunflower oil (high linole), sunflower oil (high oleic), cottonseed oil, palm oil, peanut oil, beef tallow, lard and the like. Moreover, the mixed oil which mixed these 2 or more types may be sufficient. MCT, olive oil, sesame oil, rice bran oil, palm kernel oil, coconut oil, or a mixed oil thereof is preferable. More preferred is MCT. Here, as the medium chain fatty acid in the medium chain fatty acid triglyceride, for example, the medium chain fatty acid triglyceride standardized in the pharmaceutical additive standard 2003 can be suitably used.
The volatile organic compound added to the oil having a linolenic acid content of 1.5% by mass or less is not particularly limited as long as the content is clear. For example, a commercially available reagent can be used suitably.
In the present invention, the standard solution refers to a solution having a known volatile organic compound concentration. The standard solution can be prepared, for example, by accurately weighing each of fats and oils and volatile organic compounds having a linolenic acid content of 1.5% by mass or less and mixing them.

The analytical instrument used for the instrumental analysis is not particularly limited. For example, gas chromatography (GC), liquid chromatography (LC) (for example, high performance liquid chromatography (HPLC), ultra high performance liquid chromatography (UPLC)), mass spectrometry ( MS), infrared spectroscopy (IR), near infrared spectroscopy (NIR), nuclear magnetic resonance analysis (NMR) and the like. These instrumental analyzes may be combined, and examples thereof include GC / MS, LC / MS (particularly HPLC / MS, UPLC / MS) and the like. GC, LC (particularly HPLC, UPLC), MS, GC / MS or LC / MS (particularly HPLC / MS, UPLC / MS) are preferred.
The apparatus used for these instrumental analysis is not specifically limited, What is necessary is just to be able to measure the volatile organic compound contained in a sample. The measurement conditions can be appropriately set so as to be appropriate for the measurement of the volatile organic compound.
When GC is used for instrumental analysis, it is preferable to use a head space method, a purge trap method, or the like. The head space method is preferable. When the headspace method is used, the incubation temperature is preferably about 40 to 120 ° C, more preferably about 40 to 60 ° C, and further preferably about 53 to 55 ° C. It is preferable to use a WAX column as the column. The temperature rise is preferably 40 ° C to 250 ° C. The GC analysis result can be obtained as the peak area value of the volatile organic compound in the standard solution.

  The calibration curve can be prepared according to a known method. For example, when the peak area value of a standard solution is obtained by GC, the peak area value is taken on the vertical axis, the volatile organic compound concentration is taken on the horizontal axis, and the peak area value and concentration of each standard solution are plotted. Can be created.

Step (3): Evaluation of the effect on the flavor of food In this step, the content of the substance in the evaluation target oil and fat is compared with the content of the substance in the comparison target fat and oil, thereby affecting the flavor of the food. To evaluate. For example, when the content of the volatile organic compound in the evaluation target oil / fat is higher than the content of the substance in the comparison target oil / fat, the flavor of the food can be evaluated as impossible.

For example, when acrolein is used as the volatile organic compound, the content of acrolein in the oil to be evaluated is preferably 5 ppb or more, more preferably 10 ppb or more, and even more preferably 20 ppb or more with respect to the content of acrolein in the comparison oil or fat. In some cases, the flavor of the food can be evaluated as not possible.
Further, for example, when propanal is used as the volatile organic compound, the content of propanal in the evaluation target fat is preferably 2 ppb or more, more preferably 4 ppb or more, more preferably relative to the content of propanal in the comparison target fat or oil. When the amount is preferably 6 ppb or more, the flavor of the food can be evaluated as impossible.

In the step (3), the content of the volatile organic compound in the evaluation target oil or fat is, for example, 1.2 times or more, preferably 1.5 or more times, more preferably twice as much as the content of the substance in the comparison target oil or fat. As mentioned above, when it is more preferably 3 times or more, particularly preferably 4 times or more, the flavor of the food can be evaluated as impossible.
In the step (3), the flavor of the food may be evaluated using the contents of two or more volatile organic compounds. That is, when the content of two or more kinds of volatile organic compounds is used as an index, the total content of two or more kinds of volatile organic compounds in the oil to be evaluated is two or more kinds of volatile organics in the oil to be compared. When the total content of the compounds is, for example, 1.2 times or more, preferably 1.5 times or more, more preferably 2 times or more, even more preferably 3 times or more, particularly preferably 4 times or more, the flavor of the food is not possible. Can be evaluated.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to these.

(Experimental conditions)
Experiments were performed using the following raw materials and measuring equipment. In this example, commercially available materials, instruments, measuring instruments and the like were used unless otherwise specified.

(material)
Rice oil, manufactured by Tsukino Food Industry Co., Ltd., trade name "Kome germ oil"
Rapeseed oil Nisshin Oillio Group, trade name “Nisshin Canola Oil”
Acrolein Sigma Aldrich Japan Co., Ltd., Acrolein 90% Propanal Wako Pure Chemical Industries, Ltd. Propinaldehyde 99.4% MCT Cognis Japan Co., Ltd., DELIOS SJ (F)
(measuring equipment)
Gas chromatograph detector Alfa Moss Japan Co., Ltd. Flash GC nose HERACLES II
Analytical software Alpha Moss Japan, product name "Alpha Soft"
(Measurement condition)
Column: MXT-WAX (φ0.18mm × 10m)
Carrier gas: Hydrogen Sample amount: 2 g (20 mL headspace vial)
Incubation: 55 ° C, 10 minutes Headspace injection volume: 1 mL
Syringe temperature: 65 ° C
Trap temperature: 20 ° C
Injector temperature: 220 ° C
Detector (FID) temperature: 250 ° C
Column heating conditions: 40 ° C. (10 s) to 250 ° C. (30 s) 3 ° C./second

Test 1: Measurement of volatile organic compound concentration in edible oil and fat (1) Preparation of calibration curve for acrolein Acrolein (Sigma Aldrich Japan Co., Ltd., 90% acrolein product) was accurately weighed about 1.3 mg. About 5.0 g of MCT (manufactured by Cognis Japan, DELIOS SJ (F)) was accurately weighed and added to the previously weighed acrolein to prepare an acrolein MCT solution. This solution was diluted 1 to 30000 times with MCT to prepare a standard solution having an acrolein concentration of 1 to 2500 ppb, and a calibration curve was prepared using the standard solution.

(2) Preparation of calibration curve for propanal About 5 mg of propanal (manufactured by Wako Pure Chemical Industries, Ltd., 99.4% propyne aldehyde) was accurately weighed. About 5.0 g of MCT (manufactured by Cognis Japan, DELIOS SJ (F)) was accurately weighed and added to the previously weighed propanal to prepare a propanal MCT solution. This solution was diluted 5 to 10,000 times with MCT to prepare a standard solution having a propanal concentration of 1 to 2000 ppb, and a calibration curve was prepared using this standard solution.

(3) Preparation and Measurement of 180 ° C. Heated Oil 2 g of rapeseed oil was placed in an aluminum block thermostatic bath and heated at an oil temperature of 180 ° C. for 2 hours to prepare rapeseed oil (180 ° C. heated oil). After the rapeseed oil was cooled to room temperature, the peak area values of acrolein and propanal were determined using the flash GC nose HERACLES II under the above measurement conditions. The acrolein concentration and propanal concentration in rapeseed oil (180 ° C. heated oil) were calculated using the calibration curve created earlier.
2 g of rice oil was put in an aluminum block thermostat and heated at an oil temperature of 180 ° C. for 2 hours to prepare rice oil (180 ° C. heating oil). About the said fats and oils, the peak area value of acrolein and a propanal was calculated | required on the said measurement conditions using flash GC nose HERACLES II. The acrolein concentration and propanal concentration in the rice oil (180 ° C. heated oil) were calculated using the calibration curve created earlier.
[FIG. 1] shows the measurement results of acrolein and propanal in edible fats and oils of rapeseed oil (180 ° C. heated oil) and rice oil (180 ° C. heated oil). In the following [FIG. 1] to [FIG. 4], propanal is a substance having a peak at a retention time of about 17.5. Acrolein is a substance having a peak at a retention time of about 20.9.

(4) Measurement of unheated oil Unheated rapeseed oil (hereinafter referred to as rapeseed oil (unheated)) within one month after production and unheated rice oil (hereinafter referred to as rice oil (unheated) within one month after production) The peak area values of acrolein and propanal were determined using a flash GC nose HERACLES II. About each fat and oil, the acrolein density | concentration and the propanal density | concentration were each calculated using the calibration curve created previously.

(5) Preparation and measurement of added oil Acrolein and propanal are added to rapeseed oil (unheated), and rapeseed oil (heated at 180 ° C.), acrolein, and propanal concentration are almost the same (hereinafter referred to as rapeseed oil (added oil)). .) Was prepared.
Acrolein and propanal were added to rice oil (unheated) to prepare a fat (hereinafter referred to as rice oil (added oil)) having substantially the same concentration of acrolein and propanal as rice oil (heated at 180 ° C.).
The acrolein concentration and propanal concentration of the rapeseed oil (added oil) and rice oil (added oil) were measured by the same procedure as in (4) above.

Test 2: Measurement of volatile organic compound concentration in water extract of edible oil and fat (1) Preparation of water extract The rapeseed oil (180 ° C. heating oil) prepared in Test 1 was used. The same amount of water was added to the rapeseed oil, and the mixture was stirred and mixed at 40 ° C. for 1 minute. This was centrifuged to separate the aqueous phase, and an aqueous extract was prepared.
In the same procedure, the water extract of rapeseed oil (added oil), rapeseed oil (unheated), rice oil (180 ° C heated oil), rice oil (added oil), and rice oil (unheated) used in Test 1 was used. Each was prepared.

(2) Measurement of concentration of volatile organic compound in water extract Using flash GC nose HERACLES II, peak area values of acrolein and propanal in each water extract were determined. The acrolein concentration and propanal concentration in the water extract were calculated using the calibration curve prepared earlier.

The results of Test 1 and Test 2 are shown in [Table 1].
[FIG. 2] shows the measurement results of acrolein and propanal in water extracts of rapeseed oil (180 ° C. heated oil) and rice oil (180 ° C. heated oil).
FIG. 3 shows the measurement results of edible fat and water extract for rapeseed oil (heated at 180 ° C.). In FIG. 3, hydrocarbons having no functional group did not affect the flavor of food. Moreover, since the substance eluted with the retention time of 30 or more is a substance that is difficult to dissolve in a polar solvent due to its large molecular weight, it did not affect the flavor of food.
FIG. 4 shows the measurement results of the contents of acrolein and propanal in edible fats and oils and rapeseed oil (heated oil at 180 ° C.).

Test 3: Taste sensory test was conducted by 20 monitors using the water extract prepared by the evaluation test 2 of the flavor of fats and oils by a two-point discrimination method . Compare the taste of the oil to be evaluated with the oil to be compared, and if the number of persons judged that the oil to be evaluated has a more unpleasant taste is 5 or less, “good”, and 6 to 14 people "In the case of 15 or more people, each was evaluated as" impossible ".

(Examples 1-4)
In Example 1, the rapeseed oil (180 ° C. heating oil) was used as the evaluation target oil and fat, and the rice oil (180 ° C. heating oil) was used as the comparison target oil and fat. Similarly, a taste sensory test was performed in the same manner as in Example 1 for each group shown in the following [Table 2]. The results are shown in [Table 2].
The acrolein concentration and propanal concentration in [Table 2] are both concentrations in the water extract. The results of the sensory test in [Table 2] indicate the number of persons judged that the evaluation target oil or fat has a more unpleasant taste among the total number of monitors (20 persons). In the results of the sensory test in [Table 2], * indicates that there is a statistically significant difference at a risk rate of 5%.

(Evaluation)
From the results of the sensory test, it was found that in Example 1, the evaluation target fats and oils were statistically significantly worse than the comparison target fats and oils.
On the other hand, the acrolein concentration in the evaluation target oil and fat in Example 1 was about 4.7 times the acrolein concentration in the comparison target oil and fat. Moreover, in Example 1, the propanal concentration in the evaluation target oil and fat was about 5.4 times the propanal concentration in the comparison target oil and fat.

From the results of the sensory test, it was found that in Example 2, the evaluation target fats and oils were statistically significantly worse than the comparison target fats and oils.
On the other hand, in Example 2, the acrolein concentration in the evaluation target oil was about 4.7 times the acrolein concentration in the comparison target oil. Moreover, in Example 2, the propanal concentration in the evaluation target oil and fat was about 6.2 times the propanal concentration in the comparison target oil and fat.
From Examples 1 and 2, when the content of the volatile organic compound in the evaluation target oil or fat is larger than the content of the substance in the comparison target oil or fat, the flavor of the food can be evaluated as being impossible.

From the results of the sensory test, it was found that in Examples 3 and 4, the taste of the evaluation target oil and fat had no statistically significant difference from the comparison target oil and fat.
On the other hand, in Example 3 and Example 4, both the acrolein concentration and the propanal concentration of the evaluation object oil and the comparison object oil were the same.

  Since this invention can provide the method of evaluating the influence on the flavor of the foodstuff by deterioration of edible fats and oils, it can use industrially useful, for example in manufacture of a foodstuff using edible fats and oils, evaluation, etc.

Claims (5)

A method for evaluating the influence of food oil and fat on the flavor of food,
(1) A step of preparing a polar solvent extract of an evaluation object oil and a comparison object oil;
(2) A step of measuring the content of the volatile organic compound in the polar solvent extract, and (3) comparing the content of the substance in the evaluation target oil and fat with the content of the substance in the comparison target fat and oil. Process to evaluate the impact on the flavor of food,
Including methods.   The method according to claim 1, wherein, in step (3), when the content of the volatile organic compound in the evaluation target oil or fat is greater than the content of the substance in the comparison target fat or oil, the flavor of the food is evaluated as unacceptable.   The method according to claim 1, wherein the volatile organic compound is one or more selected from aldehydes having 1 to 11 carbon atoms.   The method according to claim 1, wherein the volatile organic compound is acrolein and / or propanal.   In step (2), the content of the volatile organic compound in the polar solvent extract by gas chromatography, liquid chromatography, mass spectrometry, a combination of gas chromatography and mass spectrometry, or a combination of liquid chromatography and mass spectrometry. The method in any one of Claims 1-4 which measures each.