Frozen broccoli and manufacturing method thereof

Abstract

The invention provides frozen broccoli with improved broccoli flavor. In the frozen broccoli, the ratio of the peak area of phenylacetaldehyde to the peak area of 1-octylene-3-ketone, which is obtained by gas chromatography-mass spectrometry, is adjusted within the range of 2.5-5.5.

Description

Technical Field

[0001] The present disclosure relates to frozen broccoli and methods of making the same. Background Art

[0002] Frozen broccoli is widely used due to its convenience, but it often has a weaker aroma than normal broccoli and has a different flavor from the original broccoli.

[0003] In order to enhance the body of food and beverages containing cruciferous vegetables, a method of adjusting the content ratio of phenylacetaldehyde, 2-hexenal, 1-octen-3-one, dimethyl trisulfide and butyl isothiocyanate to a specific range has been studied (for example, Patent Document 1).

[0004] However, Patent Document 1 does not disclose improving the flavor of frozen broccoli.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2018-191541 Summary of the invention

[0008] Problems to be solved by the invention

[0009] An object of one embodiment of the present invention is to improve the flavor of frozen broccoli.

[0010] According to one embodiment of the present disclosure, there is provided frozen broccoli containing phenylacetaldehyde and 1-octen-3-one, wherein the ratio of the peak area of ​​the phenylacetaldehyde to the peak area of ​​the 1-octen-3-one obtained by gas chromatography-mass spectrometry is 2.5 to 5.5.

[0011] According to another embodiment of the present invention, there is provided a frozen broccoli containing phenylacetaldehyde, 1-octen-3-one, dimethyl disulfide and methylthiopropionaldehyde, wherein the ratio of the total peak area of ​​the phenylacetaldehyde and the dimethyl disulfide to the total peak area of ​​the 1-octen-3-one and the methylthiopropionaldehyde obtained by gas chromatography-mass spectrometry is 2.3 to 8.0.

[0012] According to another embodiment of the present disclosure, a method for producing frozen broccoli can be provided, comprising: a step of adjusting the ratio of the peak area of ​​phenylacetaldehyde obtained by gas chromatography-mass spectrometry in the broccoli to the peak area of ​​1-octen-3-one to 2.5 to 5.5; and a step of freezing the broccoli.

[0013] According to another embodiment of the present disclosure, a method for producing frozen broccoli can be provided, which comprises: a step of adjusting the ratio of the total peak area of ​​phenylacetaldehyde and dimethyl disulfide obtained by gas chromatography-mass spectrometry in the broccoli to the total peak area of ​​1-octen-3-one and methylthiopropionaldehyde to 2.3 to 8.0; and a step of freezing the above-mentioned broccoli.

[0014] Effects of the Invention

[0015] According to the present disclosure, the broccoli flavor of frozen broccoli can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] [ Figure 1 ] Figure 1 This is an example of a flow chart of the method for producing frozen broccoli of the present disclosure.

[0017] [ Figure 2 ] Figure 2 This is a graph showing the distribution of the values ​​of the ratio of the peak area of ​​(A) phenylacetaldehyde to the peak area of ​​(B) 1-octen-3-one (peak area ratio (A) / (B)) obtained by gas chromatography-mass spectrometry in frozen broccoli in each test area and comparison area, and frozen broccoli prepared by a process different from that in each test area and comparison area.

[0018] [ Figure 3 ] Figure 3 It is a graph showing the distribution of the values ​​of the ratio of the total peak area of ​​(A) phenylacetaldehyde and (C) dimethyl disulfide to the total peak area of ​​(B) 1-octen-3-one and (D) methylthiopropionaldehyde (peak area ratio [(A)+(C)] / [(B)+(D)]) obtained by gas chromatography-mass spectrometry in frozen broccoli in each test area and comparison area, and frozen broccoli prepared by a process different from that in each test area. DETAILED DESCRIPTION

[0019] The present invention provides broccoli that is rich in flavor or nutrition, thereby providing food safety and peace of mind, and plays a part in promoting the realization of a sustainable society.

[0020] [Frozen broccoli]

[0021] According to one embodiment, a frozen broccoli (hereinafter also referred to as "the frozen broccoli of the present disclosure") is provided, which contains phenylacetaldehyde and 1-octen-3-one, and the ratio of the peak area of ​​phenylacetaldehyde to the peak area of ​​1-octen-3-one obtained by gas chromatography-mass spectrometry is within a specific range. The frozen broccoli of the present disclosure is particularly frozen broccoli for natural thawing or microwave cooking. It should be noted that the frozen broccoli of the present disclosure also includes a collection of multiple frozen broccoli that satisfy the above-mentioned peak area ratio (for example, multiple packaged broccoli).

[0022] In the frozen broccoli disclosed in the present invention, the ratio of the peak area of ​​(A) phenylacetaldehyde to the peak area of ​​(B) 1-octen-3-one obtained by gas chromatography-mass spectrometry (hereinafter also referred to as "peak area ratio (A) / (B)") is 2.5 to 5.5, preferably 2.6 to 5.3, more preferably 2.7 to 5.0, and particularly preferably 2.8 to 4.8. By making the peak area ratio (A) / (B) in the above range, the frozen broccoli disclosed in the present invention has an improved broccoli flavor when thawed and eaten compared to conventional frozen broccoli. That is, the frozen broccoli disclosed in the present invention has a sufficient broccoli flavor.

[0023] The "broccoli flavor" in the present disclosure refers to the aroma felt when raw broccoli is cooked or otherwise eaten at home, and specifically refers to the flavor of green fresh vegetables, sweetness, spiciness like wasabi, bitterness, and the like, as well as their concentrations.

[0024] One of the reasons why the frozen broccoli of the present disclosure is considered to have a sufficient broccoli flavor is as follows. That is, it is considered that the frozen broccoli of the present disclosure contains a sufficient amount of 1-octen-3-one and the content of phenylacetaldehyde is reduced to a certain extent, so that the broccoli flavor can be felt without feeling an unpleasant flavor or foreign smell.

[0025] Frozen broccoli according to another embodiment contains phenylacetaldehyde, 1-octen-3-one, dimethyl disulfide and methylthiopropionaldehyde, and the ratio of the total peak area of ​​(A) phenylacetaldehyde and (C) dimethyl disulfide to the total peak area of ​​(B) 1-octen-3-one and (D) methylthiopropionaldehyde obtained by gas chromatography-mass spectrometry (hereinafter also referred to as "peak area ratio [(A)+(C)] / [(B)+(D)]" is within a specific range. Specifically, the peak area ratio [(A)+(C)] / [(B)+(D)] of the frozen broccoli of the present disclosure is preferably 2.3 to 8.0, more preferably 2.4 to 7.5, further preferably 2.5 to 7.0, and particularly preferably 2.6 to 6.8. By making the peak area ratio [(A)+(C)] / [(B)+(D)] within the above range, the broccoli flavor can be more reliably achieved compared to the case where the above peak area ratio (A) / (B) is adjusted.

[0026] The above-mentioned phenylacetaldehyde, 1-octen-3-one, dimethyl disulfide and methylthiopropionaldehyde can be derived from the raw material of frozen broccoli, such as broccoli itself, or can be generated during the production process of frozen broccoli, or can be added during the production process of frozen broccoli. The above-mentioned components are preferably derived from the broccoli itself as the raw material.

[0027] Specifically, the peak areas of the above-mentioned phenylacetaldehyde, 1-octen-3-one, dimethyl disulfide and methylthiopropionaldehyde can be obtained by gas chromatography-mass spectrometry (GC / MS) according to the following steps. First, a gas chromatography-mass spectrometry analysis system 7890GC / 5977MSD manufactured by Agilent Technologies, equipped with a multifunctional automatic sampler MPS robotic, a dynamic headspace (DHS) module, a thermal desorption unit (TDU) and a temperature-increasing vaporization injection port (CIS4) manufactured by GERSTEL, is used as an analysis device. The broccoli to be analyzed is crushed to prepare a sample, 3.0 g of the sample is measured into a dedicated vial, and the aroma components are captured into a dedicated Tenax TA tube using the dynamic headspace (DHS) method, and thermal desorption analysis is performed using the TDU-1D-GC / MS system. The conditions of the GC / MS method are as follows.

[0028] Column: DB-WAX manufactured by Agilent Technologies (length 30 m×inner diameter 0.25 mm×film thickness 0.25 μm)

[0029] Oven temperature: 40°C (3 minutes) → 5°C / minute → 240°C (7 minutes)

[0030] MS mode: SCAN (mass range 29-350)

[0031] It should be noted that when frozen broccoli was the object of analysis, the frozen broccoli was left to stand at room temperature for 2 hours to thaw and then analyzed.

[0032] In a preferred embodiment, the frozen broccoli of the present disclosure is obtained by freezing heated broccoli. The conditions for heating the broccoli are not particularly limited as long as they are conditions commonly used in producing frozen broccoli, and the heating method, temperature, time, etc. can be appropriately set.

[0033] The method for heating the broccoli (heating method) is not particularly limited as long as it is a method that can fully heat the broccoli to the inside and inactivate various enzymes contained in the broccoli, and examples thereof include immersion in a heating medium such as blanching, heating with heated gas, etc. These heating methods may be used alone or in combination of two or more.

[0034] The heating medium (ie, liquid) used for scalding heating is not particularly limited as long as it is a liquid acceptable in terms of food hygiene, but water is preferably used.

[0035] The heating using the heated gas may be wet heating using steam or dry heating without using steam. As wet heating, for example, heating using saturated steam or superheated steam using a steam oven, a water oven, etc. may be cited. It should be noted that wet heating may be heating using steam at a saturation temperature (saturated steam) or heating using steam at a temperature exceeding the saturation temperature (superheated steam). As the gas used in wet heating, there is no particular limitation as long as it is a gas derived from a liquid that is permitted in food hygiene, and water (i.e., water vapor) is preferably used as the gas. In addition, as dry heating, for example, heating using heated air using a convection oven may be cited. As the gas used in dry heating, there is no particular limitation as long as it is a liquid that is permitted in food hygiene, and air is preferably used.

[0036] As a heating method, heating with gas is preferably used, and wet heating, that is, heating with saturated steam and / or superheated steam is more preferably used, and heating with saturated steam and / or superheated steam of water is particularly preferred. By heating the broccoli with gas, it is possible to suppress the loss of components contained in the broccoli during the heating process, and as a result, it is possible to suppress the reduction in the content of flavor components, nutritional components, etc. in the obtained frozen broccoli.

[0037] The temperature for heating the broccoli (heating temperature) can be set appropriately as long as the broccoli is fully heated to the inside and the various enzymes contained in the broccoli are inactivated, according to the above-mentioned heating method and the relationship with the heating time described below. It should be noted that the "heating temperature" refers to the temperature of the liquid or gas used for heating.

[0038] When the heating method is boiling heating, the heating temperature can be, for example, 70 to 110° C., 80 to 105° C., 90 to 100° C., etc., preferably around the boiling point of the liquid used. Specifically, when boiling heating is performed with water, the heating temperature in Japan is preferably around 100° C.

[0039] When the heating method is dry heating using gas, the heating temperature can be, for example, 90 to 250° C., 100 to 200° C., 110 to 180° C., etc. When the heating method is heating (wet heating) using water (steam) using gas, the heating temperature is the saturation temperature of water (100° C. under standard atmospheric pressure) or a temperature higher than that, for example, 100 to 200° C., 105 to 180° C., 110 to 130° C., etc.

[0040] By setting the heating temperature in various heating methods to the above range, it is possible to prevent the broccoli from having an unpleasant odor, being excessively softened, and having a deteriorated texture.

[0041] The time for heating the broccoli (heating time) may be a time sufficient to fully heat the inside of the broccoli and inactivate various enzymes contained in the broccoli, and can be appropriately set according to the relationship between the above-mentioned heating method and the heating time.

[0042] When the heating method is boiling heating, the heating time can be set to, for example, 30 to 300 seconds, 45 to 200 seconds, 60 to 150 seconds, etc.

[0043] When the heating method is dry heating using gas, the heating time can be, for example, 100 to 600 seconds, 120 to 450 seconds, 180 to 300 seconds, etc. In addition, when the heating method is wet heating using gas, the heating time can be, for example, 40 to 250 seconds, 50 to 180 seconds, 60 to 120 seconds, etc.

[0044] By setting the heating time in various heating methods to the above range, the enzymes present in the broccoli can be inactivated, the deterioration of the broccoli caused by the enzymes can be reduced, and by avoiding overheating, excessive softening and deterioration of the taste can be reduced. In particular, when the heating method is blanching, the components contained in the broccoli are easily lost during the heating process. Therefore, from the viewpoint of maintaining the flavor components, nutritional components, etc. in the obtained frozen broccoli, it is preferable to shorten the heating time.

[0045] In a particularly preferred embodiment, in the case of scalding heating, the heating temperature and the heating time are 60 to 100 seconds at 70 to 120° C., 60 to 100 seconds at 80 to 110° C., and 60 to 100 seconds at 90 to 100° C. In addition, in the case of dry heating using gas, the heating temperature and the heating time are 60 to 300 seconds, 100 to 250 seconds, or 120 to 200 seconds at 70 to 120° C., 60 to 300 seconds, 100 to 250 seconds, or 120 to 200 seconds at 80 to 110° C., and 60 to 300 seconds, 100 to 250 seconds, or 120 to 200 seconds at 90 to 100° C. In addition, when the heating method is wet heating using gas, the heating temperature and heating time are 40 to 200 seconds, 50 to 150 seconds or 60 to 120 seconds at 90 to 150°C, 40 to 200 seconds, 50 to 150 seconds or 60 to 120 seconds at 95 to 140°C, and 40 to 200 seconds, 50 to 150 seconds or 60 to 120 seconds at 100 to 130°C. In particular, when the heating method is wet heating using gaseous water (saturated steam), the heating temperature and heating time are 100 to 200 seconds, 110 to 180 seconds or 120 to 150 seconds at 80 to 100°C, 199 to 200 seconds, 110 to 180 seconds or 120 to 150 seconds at 90 to 100°C, and 100 to 200 seconds, 110 to 180 seconds or 120 to 150 seconds at 95 to 100°C. In addition, when the heating method is wet heating using gas water (superheated steam), the heating temperature and heating time are 40 to 200 seconds, 50 to 150 seconds or 60 to 90 seconds at a temperature exceeding 100 to 150°C, 40 to 200 seconds, 50 to 150 seconds or 60 to 90 seconds at a temperature exceeding 100 to 140°C, and 40 to 200 seconds, 50 to 150 seconds or 60 to 90 seconds at a temperature exceeding 100 to 130°C.

[0046] In a preferred embodiment, the frozen broccoli of the present disclosure is obtained by freezing the heated and then cooled broccoli. The conditions for cooling the heated broccoli are not particularly limited as long as they are the conditions commonly used when manufacturing frozen broccoli, and the cooling method, temperature, time, etc. can be appropriately set.

[0047] The method for cooling the broccoli (cooling method) is not particularly limited as long as the heated broccoli does not cause adverse conditions in the freezing equipment and can be frozen at a sufficient speed. For example, cooling with a liquid (cooling medium) having a lower temperature than the heated broccoli (hereinafter also referred to as "cooling with liquid"), cooling with a gas having a lower temperature than the heated broccoli (hereinafter also referred to as "cooling with gas"), etc. These cooling methods can be used alone or in combination of two or more.

[0048] As cooling by liquid, there can be mentioned immersing the heated broccoli in a liquid having a lower temperature than the broccoli, spraying the heated broccoli with a liquid having a lower temperature than the broccoli, etc. The liquid used for cooling is not particularly limited as long as it is a liquid that is permissible in food hygiene, and water is preferably used.

[0049] Examples of cooling by gas include air cooling by exposing the heated broccoli to a gas atmosphere having a lower temperature than the heated broccoli, and air cooling by blowing a gas having a lower temperature than the heated broccoli to the heated broccoli. Another example of cooling by gas includes air cooling by sucking the gas around the heated broccoli and exposing the heated broccoli to the gas. The gas used for cooling is not particularly limited as long as it is a gas that is permissible in terms of food hygiene, and air is preferably used.

[0050] As a cooling method, cooling using gas is preferably used, and the above-mentioned various air cooling methods are more preferably used. It is particularly preferred to use air cooling in which the heated broccoli is exposed to a gas atmosphere having a lower temperature than the heated broccoli. By cooling the heated broccoli using gas, it is possible to suppress the loss of components contained in the broccoli during the cooling process, and as a result, it is possible to suppress the reduction in the content of flavor components, nutritional components, etc. in the obtained frozen broccoli.

[0051] The temperature (cooling temperature) at which the heated broccoli is cooled can be any temperature that can cool the heated broccoli at a sufficient speed without causing freezing, and can be appropriately set according to the above-mentioned cooling method and the relationship with the cooling time described below. It should be noted that the "cooling temperature" refers to the temperature of the liquid or gas used for cooling.

[0052] When the cooling method is cooling with liquid, the cooling temperature can be, for example, 0 to 35° C., 3 to 30° C., 5 to 25° C., etc. Specifically, when the cooling method is cooling with water, the cooling temperature is about the same temperature as tap water.

[0053] When the cooling method is cooling with gas, the cooling temperature can be, for example, -35 to 35°C, -20 to 25°C, 0 to 20°C, etc., and is preferably the temperature of the cooling environment (eg, room temperature).

[0054] By setting the cooling temperature in each cooling method to the above range, overheating of the bud portion of the broccoli in particular can be suppressed, and the desired original texture and taste of the broccoli can be maintained.

[0055] The time for cooling the broccoli (cooling time) may be a time for sufficiently cooling the heated broccoli, and can be appropriately set according to the above-mentioned cooling method and the relationship with the cooling time.

[0056] When the cooling method is cooling by liquid, the cooling time can be set to, for example, 1 to 50 seconds, 3 to 30 seconds, 5 to 15 seconds, etc. In particular, in the case of at least one of the steps of immersing the broccoli in a liquid heating medium for blanching and immersing the broccoli in a liquid cooling medium for cooling, from the viewpoint of suppressing the loss of flavor components and nutritional components of the broccoli, it is preferred that the sum of the immersion time of the liquid in the heating medium and the immersion time of the liquid in the cooling medium be less than 60 seconds.

[0057] When the cooling method is cooling using gas, the cooling time can be set to, for example, 30 to 300 seconds, 100 to 250 seconds, 120 to 200 seconds, or the like.

[0058] By making the cooling time in various cooling methods within the above range, in particular, overheating of the bud part of the broccoli is suppressed, and the desired taste and flavor of the broccoli can be maintained. In particular, when the cooling method is cooling using a liquid, the components contained in the broccoli are easily lost during the cooling process. Therefore, from the viewpoint of maintaining the aroma components, nutritional components, etc. in the obtained frozen broccoli, it is preferred to shorten the cooling time. Specifically, it is preferred that the heated broccoli is not immersed in a liquid for more than 60 seconds after heating. This is because, by immersing it in a liquid for a long time, the components contained in the broccoli are suppressed from being lost during the cooling process, and as a result, the reduction in the content of the aroma components, nutritional components, etc. in the obtained frozen broccoli is suppressed.

[0059] In a particularly preferred embodiment, when the cooling method is cooling by liquid, the cooling temperature and the cooling time are 1 to 50 seconds, 3 to 30 seconds, or 5 to 15 seconds at 0 to 35° C., 1 to 50 seconds, 3 to 30 seconds, or 5 to 15 seconds at 3 to 30° C., and 1 to 50 seconds, 3 to 30 seconds, or 5 to 15 seconds at 5 to 25° C. In addition, when the cooling method is cooling by gas, the cooling temperature and the cooling time are 60 to 300 seconds, 100 to 250 seconds, or 120 to 200 seconds at 10 to 35° C., 60 to 300 seconds, 100 to 250 seconds, or 120 to 200 seconds at 15 to 30° C., and 60 to 300 seconds, 100 to 250 seconds, or 120 to 200 seconds at 20 to 25° C.

[0060] In a preferred embodiment, the ratio of the mass of the frozen broccoli of the present invention after removing the water attached to the surface of the frozen broccoli after thawing to the mass of the frozen broccoli before thawing (i.e., the mass residual rate of the broccoli after water removal, hereinafter also referred to as the "mass residual rate") is within a specific range. Specifically, the mass residual rate is preferably 85% or more, more preferably 87% or more, and particularly preferably 89% or more. By making the mass residual rate within the above range, the seasoning effect on the thawed broccoli becomes good, and the balance as a dish can be maintained.

[0061] The mass residual rate can be specifically obtained by the following procedure.

[0062] First, the mass of the frozen broccoli before thawing was measured. Next, the frozen broccoli was placed on a metal flat plate, covered with plastic wrap, and left to thaw at room temperature for 3 hours. The thawed broccoli was placed in a salad spinner (Jumbo Vegetable Dehydrator Model 10 of Shinki Gosei Co., Ltd.) and rotated 20 times within 30 seconds to fully remove the water attached to the surface, and the mass of the broccoli after the water was removed was measured. The mass of the thawed broccoli after the water was removed was divided by the mass of the frozen broccoli before thawing to calculate the mass residual rate.

[0063] [Method for producing frozen broccoli]

[0064] According to another embodiment, a method for producing frozen broccoli (hereinafter also referred to as "the production method of the present disclosure") is provided, comprising: adjusting the ratio of the peak area of ​​phenylacetaldehyde in the broccoli obtained by gas chromatography-mass spectrometry to the peak area of ​​1-octen-3-one to 2.5 to 5.5 (with Figure 1 and freezing the broccoli (corresponding to step S1); Figure 1 The frozen broccoli obtained by the manufacturing method disclosed herein is particularly frozen broccoli for natural thawing or microwave cooking.

[0065] In the manufacturing method disclosed in the present invention, the peak area ratio (A) / (B) described for the broccoli of the present invention is adjusted to 2.5 to 5.5, preferably to 2.6 to 5.3, more preferably to 2.7 to 5.0, and particularly preferably to 2.8 to 4.8. The frozen broccoli obtained by the manufacturing method disclosed in the present invention has an improved broccoli flavor when thawed and eaten compared to conventional frozen broccoli by adjusting the peak area ratio (A) / (B) to the above range. That is, the frozen broccoli obtained by the manufacturing method disclosed in the present invention fully possesses the broccoli flavor.

[0066] As a method for adjusting the peak area ratio, for example, appropriately setting the heating method, heating temperature and / or heating time in the heat treatment for inactivating various enzymes contained in the broccoli can be cited. In addition, as another method for adjusting the peak area, appropriately setting the cooling method, cooling temperature and / or cooling time in the cooling treatment before freezing the heat-treated broccoli can be cited. In addition, as another method for adjusting the peak area, adding components of phenylacetaldehyde and / or 1-octen-3-one to the heating medium (liquid or gas) during the heating treatment and / or the cooling medium (liquid or gas) during the cooling treatment can be cited.

[0067] According to the production method disclosed herein, frozen broccoli can be obtained by freezing broccoli that has undergone the step of adjusting the peak area ratio (A) / (B) to the above range. The conditions for freezing broccoli are not particularly limited as long as they are the conditions commonly used in producing frozen broccoli, and the freezing temperature, time, etc. can be appropriately set.

[0068] The temperature and time for freezing broccoli are appropriately set, for example, so that the maximum ice crystal formation zone passage time is 5 to 20 minutes and the time until freezing is completed is 10 to 30 minutes. By setting the temperature and time for freezing broccoli to such a range, it is possible to maintain a moderate hardness with good crispness in the broccoli after thawing. It should be noted that the maximum ice crystal formation zone passage time refers to the time required for the core material temperature of the broccoli to be frozen to pass through the temperature zone of 0 to -10°C, and the time until freezing is completed refers to the time required for the core material temperature to reach -18°C.

[0069] The manufacturing method of other embodiments includes a step of adjusting the peak area ratio [(A)+(C)] / [(B)+(D)] described for the broccoli of the present disclosure to a specific range. Specifically, in the manufacturing method of the present disclosure, the peak area ratio [(A)+(C)] / [(B)+(D)] is preferably adjusted to 2.3 to 8.0, more preferably to 2.4 to 7.5, further preferably to 2.5 to 7.0, and particularly preferably to 2.6 to 6.8. The frozen broccoli obtained by the manufacturing method of the present disclosure can more reliably achieve the broccoli flavor by adjusting the peak area ratio [(A)+(C)] / [(B)+(D)] to the above range, compared with the case of adjusting the above peak area ratio (A) / (B).

[0070] As a method for adjusting the peak area ratio, for example, appropriately setting the heating method, heating temperature and / or heating time in the heat treatment for inactivating various enzymes contained in the broccoli can be cited. In addition, as another method for adjusting the peak area, appropriately setting the cooling method, cooling temperature and / or cooling time in the cooling treatment before freezing the heat-treated broccoli can be cited. In addition, as another method for adjusting the peak area, adding each component of phenylacetaldehyde, 1-octen-3-one, dimethyl disulfide and / or methylthiopropionaldehyde to the heating medium (liquid or gas) during the heating treatment and / or the cooling medium (liquid or gas) during the cooling treatment can be cited.

[0071] The components of phenylacetaldehyde, 1-octen-3-one, dimethyl disulfide and methylthiopropionaldehyde contained in the frozen broccoli may be derived from the raw material of the frozen broccoli, such as the broccoli itself, or may be generated during the production process of the frozen broccoli, or may be added during the production process of the frozen broccoli. The above components are preferably derived from the broccoli itself as the raw material.

[0072] The peak areas of the above-mentioned phenylacetaldehyde, 1-octen-3-one, dimethyl disulfide and methylthiopropionaldehyde and their ratios can be obtained by the same procedures as those described for the broccoli of the present disclosure.

[0073] In a preferred embodiment, the manufacturing method of the present disclosure includes a step of heating the broccoli before freezing the broccoli to obtain frozen broccoli. The conditions for heating the broccoli are not particularly limited as long as they are the conditions commonly used when manufacturing frozen broccoli, and the heating method, temperature, time, etc. can be appropriately set. Specifically, the conditions can be set to be the same as the conditions described for the broccoli of the present disclosure above.

[0074] In a preferred embodiment, the manufacturing method of the present disclosure includes a step of cooling the broccoli after heating the broccoli and before freezing the broccoli. The conditions for cooling the broccoli are not particularly limited as long as they are the conditions commonly used when manufacturing frozen broccoli, and the cooling method, temperature, time, etc. can be appropriately set. Specifically, the conditions can be the same as those described for the broccoli of the present disclosure above.

[0075] In a preferred embodiment, the manufacturing method of the present disclosure includes a step of adjusting the mass residual rate described for the broccoli of the present disclosure to a specific range. The mass residual rate is preferably adjusted to 85% or more, more preferably adjusted to 87% or more, and particularly preferably adjusted to 89% or more. By adjusting the mass residual rate to the above range, the seasoning effect on the thawed broccoli becomes good, and the balance as a dish can be maintained.

[0076] Each of the above steps may be performed independently as one step, or two or more steps may be performed in parallel.

[0077] The manufacturing method of the present disclosure may include other steps in addition to the above steps. The other steps are not particularly limited as long as they are steps commonly used in the production of frozen broccoli, and examples thereof include washing the raw material broccoli and glazing the frozen broccoli.

[0078] The manufacturing method of the present disclosure may also include a step of packaging a plurality of frozen broccoli satisfying the above-mentioned range of the peak area ratio (A) / (B). That is, according to the manufacturing method of the present disclosure, in addition to being able to obtain frozen broccoli satisfying the above-mentioned range of the peak area ratio (A) / (B), it is also possible to obtain a collection (e.g., packaged frozen broccoli) containing a plurality of such frozen broccoli.

[0079] Example

[0080] Hereinafter, the present disclosure will be specifically described based on examples, but the present disclosure and the scope of rights are not limited to the description of the examples.

[0081] Preparation Example 1: Preparation of Frozen Broccoli in the Experimental Area

[0082] The frozen broccoli of each test area 1 to 7 was prepared according to the following steps.

[0083] Test Area 1

[0084] The broccoli (obtained on January 24, 2022, produced in Aichi Prefecture) was divided into small clusters in a manner that the diameter of the flower buds was 30 mm or more, the part with a large diameter of the flower buds was divided into 55 mm squares, and the pedicel was cut and removed in a manner that the length was also within 55 mm. Next, the treated broccoli was immersed in water for washing, and a continuous steamer (SO-0935S manufactured by Kiyomoto Iron Works Co., Ltd.) was used, the outlet pressure was set to 0.003 MPa, the steam temperature was set to 100°C, and heated for 120 seconds. After air cooling at room temperature for 180 seconds, it was frozen at -35°C using a blast freezer to obtain frozen broccoli in test area 1.

[0085] Test Area 2

[0086] Instead of the broccoli produced in Aichi Prefecture obtained on January 24, 2022, broccoli produced in Tottori Prefecture obtained on May 19 was used, and the heating conditions of the continuous steamer were changed to an outlet pressure of 0.02 MPa, a steam temperature of 130°C, and a heating time of 90 seconds. Except for this, the same operation was performed as the preparation of the frozen broccoli in the above-mentioned test area 1 to obtain the frozen broccoli in test area 2.

[0087] Test Area 3

[0088] The broccoli (obtained on August 22, 2022, produced in Nagano Prefecture) was divided into small clusters so that the diameter of the buds was 30 mm or more, the part with a large diameter of the buds was divided into 55 mm squares or less, and the pedicel was cut and removed so that the length was also within 55 mm. Next, the treated broccoli was immersed in water for washing, and heated for 150 seconds in a convection oven (FSCCWE61E manufactured by FUJIMAC Co., Ltd.) in a steaming mode, a steam temperature of 90°C, and a wind setting of 4. After immersion in cooling water at about 5°C for cooling for 10 seconds, the water was gently removed, and frozen at -35°C using a blast freezer to obtain frozen broccoli of test area 3.

[0089] Test Area 4

[0090] The broccoli (obtained on August 22, 2022, produced in Nagano Prefecture) was divided into small clusters so that the diameter of the flower buds was 30 mm or more, the part with a large diameter of the flower buds was divided into 55 mm squares, and the pedicel was cut and removed so that the length was also within 55 mm. Next, the treated broccoli was immersed in water for washing, heated in boiling hot water (100°C) for 85 seconds, air-cooled at room temperature for 180 seconds, and frozen at -35°C using a blast freezer to obtain frozen broccoli of test area 4.

[0091] Test Area 5

[0092] Frozen broccoli of Test Section 5 was obtained in the same manner as in the preparation of the frozen broccoli of Test Section 1, except that broccoli produced in Aichi Prefecture obtained on January 12, 2022 was used instead of the broccoli produced in Aichi Prefecture obtained on January 24, 2022.

[0093] Test Area 6

[0094] Instead of the broccoli produced in Aichi Prefecture obtained on January 24, 2022, broccoli produced in Tottori Prefecture obtained on May 19, 2022 was used, and the heating conditions of the continuous steamer were changed to an outlet pressure of 0.02 MPa, a steam temperature of 130°C, and a heating time of 60 seconds. Except for this, the same operation was performed as that for the preparation of the frozen broccoli in the above-mentioned test area 1, to obtain the frozen broccoli in test area 6.

[0095] Test Area 7

[0096] Broccoli (obtained on May 19, 2022, produced in Tottori Prefecture) was divided into small clusters so that the diameter of the flower buds was 30 mm or more, and the part with a large diameter of the flower buds was divided into 55 mm squares or less, and the pedicel was cut and removed so that the length was also within 55 mm. Next, the treated broccoli was immersed in water for washing, and heated for 150 seconds in a convection oven (FSCCWE61E manufactured by FUJIMAC Co., Ltd.) in a steaming mode, a steam temperature of 99°C, and a wind setting of 1, and then air-cooled at room temperature for 180 seconds, and then frozen at -35°C using a blast freezer to obtain frozen broccoli of test area 7.

[0097] Preparation Example 2: Preparation of Frozen Broccoli in Comparative Area

[0098] The frozen broccoli of Comparative Areas 8 to 13 were prepared according to the following steps.

[0099] Comparison Area 8

[0100] Instead of the broccoli produced in Aichi Prefecture obtained on January 24, 2022, broccoli produced in Tottori Prefecture obtained on May 19, 2022 was used, and the heating conditions of the continuous steamer were changed to an outlet pressure of 0.02 MPa, a steam temperature of 100°C, and a heating time of 480 seconds. Except for this, the same operation was performed as that for the preparation of the frozen broccoli in the above-mentioned test area 1, to obtain the frozen broccoli in the comparison area 8.

[0101] Comparison Zone 9

[0102] Instead of the broccoli produced in Aichi Prefecture obtained on January 24, 2022, broccoli produced in Tottori Prefecture obtained on May 19, 2022 was used, and the heating conditions of the continuous steamer were changed to an outlet pressure of 0.02 MPa, a steam temperature of 130°C, and a heating time of 30 seconds. Except for this, the same operation was performed as that for the preparation of the frozen broccoli in the above-mentioned test area 1, to obtain the frozen broccoli in the comparison area 9.

[0103] Comparison Zone 10

[0104] The frozen broccoli of comparison zone 10 was obtained in the same manner as the preparation of the frozen broccoli of test zone 4, except that broccoli produced in Tottori Prefecture obtained on May 19, 2022 was used instead of the broccoli produced in Nagano Prefecture obtained on August 22, 2022, and the heating time was changed to 180 seconds.

[0105] Comparison Area 11

[0106] Commercially available frozen broccoli A produced in China was used as the frozen broccoli in comparison zone 11 .

[0107] Comparison Area 12

[0108] Commercially available frozen broccoli B produced in Ecuador was used as the frozen broccoli in comparison zone 12 .

[0109] Comparison Zone 13

[0110] Instead of the broccoli produced in Aichi Prefecture obtained on January 24, 2022, broccoli produced in Tottori obtained on May 19, 2022 was used, and the heating conditions of the continuous steamer were changed to an outlet pressure of 0.02 MPa, a steam temperature of 100°C, and a heating time of 90 seconds. Except for this, the same operation was performed as that for the preparation of the frozen broccoli in the above-mentioned test area 1, to obtain the frozen broccoli in the comparison area 13.

[0111] Calculation of peak area ratio (A) / (B) and peak area ratio [(A)+(C)] / [(B)+(D)]

[0112] For each frozen broccoli of the above-mentioned test plots 1 to 7 and comparison plots 8 to 13, the peak area of ​​each component of (A) phenylacetaldehyde, (B) 1-octen-3-one, (C) dimethyl disulfide, and (D) methylthiopropionaldehyde was measured according to the following procedure. It should be noted that for each test plot and comparison plot, the peak area of ​​about 100 g (5 to 10 broccoli pieces) of frozen broccoli was measured.

[0113] First, as an analysis device, a gas chromatograph mass spectrometer system 7890GC / 5977MSD manufactured by Agilent Technologies, equipped with a multifunctional autosampler MPSrobotic manufactured by GERSTEL, a dynamic headspace (DHS) module, a thermal desorption unit (TDU), and a temperature-increasing vaporization injection port (CIS4) was used. Each frozen broccoli was placed on a flat plate, left to stand at room temperature for about 2 hours to thaw, crushed as a sample, and 3.0 g of the sample was measured in a dedicated vial. The aroma components were captured in a dedicated Tenax TA tube by the dynamic headspace (DHS) method, and thermal desorption analysis based on the TDU-1D-GC / MS system was performed. The conditions of the GC / MS method are as follows.

[0114] Column: DB-WAX manufactured by Agilent Technologies (length 30 m×inner diameter 0.25 mm×film thickness 0.25 μm)

[0115] Oven temperature: 40°C (3 minutes) → 5°C / minute → 240°C (7 minutes)

[0116] MS mode: SCAN (mass range 29-350)

[0117] Based on the peak areas of the obtained components, the peak area ratio (A) / (B) and the peak area ratio [(A)+(C)] / [(B)+(D)] were calculated. The results are shown in Table 1. In addition, the distribution of the peak area ratio (A) / (B) and the peak area ratio [(A)+(C)] / [(B)+(D)] values ​​for each frozen broccoli in the test area and the comparison area are shown in Table 1. Figure 2 and 3 .in addition, Figure 2 and Figure 3 The values ​​of each peak area ratio for the frozen broccoli prepared by a process different from that of the frozen broccoli of the test group and the comparative group are also shown.

[0118] Calculation of mass residual rate

[0119] For each frozen broccoli of the test areas 1 to 7 and the comparison areas 8 to 13, the mass residual rate was calculated according to the following steps.

[0120] First, measure the mass of each frozen broccoli before thawing. Next, place each frozen broccoli on a metal flat plate, cover with plastic wrap, and let it stand at room temperature for 3 hours to thaw. Put each thawed broccoli into a salad spinner (Jumbo Vegetable Dehydrator Model 10 of Shinhui Synthetics Co., Ltd.), and rotate it 20 times within 30 seconds to fully remove the water attached to the surface, and measure the mass of the broccoli after the water is removed. Divide the mass of each thawed broccoli after the water is removed by the mass of each frozen broccoli before thawing to calculate the mass residual rate. It should be noted that for each test area and comparison area, the mass residual rate of about 100g (5 to 10 broccoli pieces) of frozen broccoli was calculated. The results are shown in Table 1.

[0121] Sensory evaluation test

[0122] The frozen broccoli in the test areas 1 to 7 and the comparative areas 8 to 13 were subjected to a sensory evaluation test of the broccoli flavor according to the following procedure. It should be noted that the sensory evaluation test was conducted by 8 trained taste test panelists.

[0123] First, each frozen broccoli was placed on a flat plate and left to stand at room temperature for about 2 hours to thaw, and each thawed broccoli was eaten, and its broccoli flavor was evaluated according to 5 levels from -2 (no broccoli flavor) to +2 (broccoli flavor). The results are shown in Table 1. It should be noted that the numerical values ​​of the evaluation results in Table 1 are the average values ​​of 8 taste test panelists.

[0124] [Table 1]

[0125]

[0126] The results shown in Table 1 show that the frozen broccoli of Test Blocks 1 to 4, in which the ratio of the peak area of ​​(A) phenylacetaldehyde to the peak area of ​​(B) 1-octen-3-one obtained by gas chromatography-mass spectrometry was in the range of 2.5 to 5.5, had excellent broccoli flavor.

[0127] In addition, the results shown in Table 1 show that the frozen broccoli of each of the test plots 1 to 4, in which the ratio of the total peak area of ​​(A) phenylacetaldehyde and (C) dimethyl disulfide to the total peak area of ​​(B) 1-octen-3-one and (D) methylthiopropionaldehyde obtained by gas chromatography-mass spectrometry was in the range of 2.3 to 8.0, had an excellent broccoli flavor.

[0128] In particular, a comparison between test areas 1 to 3 and test area 4 shows that the frozen broccoli prepared by a heating process using gas (saturated steam or superheated steam) has a better broccoli flavor than the frozen broccoli prepared by a blanching heating process. In addition, a comparison between test areas 1 to 2 and test area 3 shows that the frozen broccoli prepared by a cooling process using gas (air cooling) has a better broccoli flavor than the frozen broccoli prepared by a cooling process using liquid (e.g., water cooling). These results indicate that by using gas for the heating process and the cooling process, the loss of components contained in the broccoli during the heating and cooling processes can be suppressed, and as a result, the reduction in the content of flavor components in the obtained frozen broccoli can be suppressed.

[0129] On the other hand, the frozen broccoli of each of Comparative Sections 8 to 13, in which the peak area ratio was outside the above range, showed inferior broccoli flavor.

[0130] Although not shown in Table 1, it was also confirmed that the frozen broccoli of each of the test plots 5 to 7 had an excellent broccoli flavor.

[0131] Possibility of industrial application

[0132] According to the present disclosure, it is possible to provide frozen broccoli with improved broccoli flavor.

[0133] [1] A frozen broccoli comprising phenylacetaldehyde and 1-octen-3-one, wherein the ratio of the peak area of ​​the phenylacetaldehyde to the peak area of ​​the 1-octen-3-one obtained by gas chromatography-mass spectrometry is 2.5 to 5.5.

[0134] [2] A frozen broccoli comprising phenylacetaldehyde, 1-octen-3-one, dimethyl disulfide and methylthiopropionaldehyde, wherein the ratio of the total peak area of ​​the phenylacetaldehyde and the dimethyl disulfide to the total peak area of ​​the 1-octen-3-one and the methylthiopropionaldehyde obtained by gas chromatography-mass spectrometry is 2.3 to 8.0.

[0135] [3] The frozen broccoli according to [1] or [2], which is obtained by heating the broccoli, wherein the heating is heating using saturated steam or superheated steam.

[0136] [4] The frozen broccoli according to any one of [1] to [3], which is obtained by heating and air-cooling the broccoli, wherein the heating is heating using saturated steam or superheated steam.

[0137] [5] The frozen broccoli according to any one of [1] to [4], wherein the mass of the frozen broccoli after removing surface water after thawing is 85% or more relative to the mass of the frozen broccoli before thawing.

[0138] [6] A method for producing frozen broccoli, comprising: a step of adjusting the ratio of the peak area of ​​phenylacetaldehyde in the broccoli to the peak area of ​​1-octen-3-one obtained by gas chromatography-mass spectrometry to 2.5 to 5.5; and a step of freezing the broccoli.

[0139] [7] A method for producing frozen broccoli, comprising: a step of adjusting the ratio of the total peak area of ​​phenylacetaldehyde and dimethyl disulfide in the broccoli obtained by gas chromatography-mass spectrometry to the total peak area of ​​1-octen-3-one and methylthiopropionaldehyde to 2.3 to 8.0; and a step of freezing the broccoli.

[0140] [8] The method according to [6] or [7], comprising the step of heating the broccoli using saturated steam or superheated steam.

[0141] [9] The method according to any one of [6] to [8], comprising a step of heating the broccoli using saturated steam or superheated steam and a step of air-cooling the broccoli after the heating step.

[0142]

[10] The method according to any one of [6] to [9], comprising the step of adjusting the mass of the frozen broccoli after removing surface water after thawing to 85% or more of the mass of the frozen broccoli before thawing.

[0143]

[11] The method according to any one of [6] to

[10] , comprising at least one of a step of immersing the broccoli in a heating medium for heating and a step of immersing the broccoli in a cooling medium for cooling, wherein the sum of the immersion time in the heating medium and the immersion time in the cooling medium is less than 60 seconds.

Claims

1. A frozen broccoli comprising phenylacetaldehyde and 1-octen-3-one, wherein the ratio of the peak area of ​​the phenylacetaldehyde to the peak area of ​​the 1-octen-3-one obtained by gas chromatography-mass spectrometry is 2.5 to 5.

5.

2. A frozen broccoli containing phenylacetaldehyde, 1-octen-3-one, dimethyl disulfide and methylthiopropionaldehyde, wherein the ratio of the total peak area of ​​the phenylacetaldehyde and the dimethyl disulfide to the total peak area of ​​the 1-octen-3-one and the methylthiopropionaldehyde obtained by gas chromatography-mass spectrometry is 2.3 to 8.

0.

3. The frozen broccoli according to claim 1 or 2, which is obtained by heating the broccoli, wherein the heating is heating using saturated steam or superheated steam. The frozen broccoli according to claim 1 or 2, which is obtained by heating and air-cooling the broccoli, wherein the heating is heating with saturated steam or superheated steam. 5 . The frozen broccoli according to claim 1 , wherein the mass of the frozen broccoli after removing surface water after thawing is 85% or more of the mass of the frozen broccoli before thawing.

6. A method for producing frozen broccoli, comprising: A step of adjusting the ratio of the peak area of ​​phenylacetaldehyde in broccoli to the peak area of ​​1-octen-3-one obtained by gas chromatography-mass spectrometry to 2.5 to 5.5; and The process of freezing the broccoli.

7. A method for producing frozen broccoli, comprising: A step of adjusting the ratio of the total peak area of ​​phenylacetaldehyde and dimethyl disulfide in broccoli to the total peak area of ​​1-octen-3-one and methylthiopropionaldehyde obtained by gas chromatography-mass spectrometry to 2.3 to 8.0; and The process of freezing the broccoli.

8. The method according to claim 6 or 7, comprising the step of heating the broccoli with saturated steam or superheated steam.

9. The method according to claim 6 or 7, comprising: A process for heating broccoli using saturated steam or superheated steam; as well as After the heating step, the broccoli is subjected to an air-cooling step. 10 . The method according to claim 6 or 7 , comprising the step of adjusting the mass of the frozen broccoli after removing surface water after thawing to 85% or more of the mass of the frozen broccoli before thawing.

11. The method according to claim 6 or 7, comprising at least one of a step of immersing the broccoli in a heating medium for heating and a step of immersing the broccoli in a cooling medium for cooling. The sum of the immersion time in the heating medium and the immersion time in the cooling medium is less than 60 seconds.

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