Method for producing frozen broccoli or frozen cauliflower, and method for improving texture of frozen broccoli or frozen cauliflower

Abstract

The present invention provides a method for producing frozen broccoli or frozen cauliflower, the method comprising a step for curing harvested broccoli or cauliflower before freezing the same, in which the combination between time and temperature in the curing is, for example, any one of (A)-(C): (A) 96-192 hours at not lower than 10°C but lower than 15°C; (B) 12-96 hours at not lower than 15°C but lower than 25°C; and (C) 3-48 hours at not lower than 25°C but lower than 40°C. The present invention alternatively provides: a method for improving the texture of frozen broccoli or frozen cauliflower, the method comprising a step for curing harvested broccoli or cauliflower before freezing the same; or a frozen broccoli having a total pectin content of 11.0 mass% or more.

Description

Method for producing frozen broccoli or frozen cauliflower and method for improving the texture of frozen broccoli or frozen cauliflower

[0001] The present disclosure relates to a method for producing, for example, frozen broccoli or frozen cauliflower and a method for improving the texture of frozen broccoli or frozen cauliflower.

[0002] Most frozen vegetables are produced through a blanching process and a freezing process. The blanching process involves heating vegetables before the freezing process. The blanching process has the following effects: improving the freezing resistance of vegetables, inhibiting discoloration of vegetables by inactivating enzymes, and sterilizing vegetables. However, frozen vegetables may have a softer texture than fresh vegetables due to changes in pectin caused by heating during the blanching process and cell destruction caused by the formation of ice crystals during the freezing process.

[0003] Among frozen vegetables, frozen broccoli is popular due to its versatility in a variety of dishes and its high nutritional value. Frozen cauliflower, like frozen broccoli, is also highly versatile and has become increasingly popular as a rice substitute. Broccoli and cauliflower are cultivated plants native to the Mediterranean, and their florets and stems are edible. Broccoli and cauliflower commonly available in Japan include those sown in spring and harvested in summer (spring crops) and those sown in summer and harvested in winter (fall-winter crops). Various varieties are cultivated to suit climatic conditions, such as cool, moderate, and warm regions. However, the optimum growth temperature is generally between 15°C and 25°C, with poor growth often observed below 5°C and above 25°C. Regarding broccoli, there are reports examining freezing methods (Non-Patent Document 1) and blanching methods (Non-Patent Document 2). However, there is still room for improvement in the texture of frozen broccoli. As with frozen broccoli, there is also a demand for improved texture for frozen cauliflower.

[0004] "Ultrasound assisted immersion freezing of broccoli (Brassica oleracea L. var. botrytis L.)", Ultrasonics Sonochemistry, September 2014, Volume 21, Issue 5, p.1728 - 1735"The effect of thermal processing on sensory properties, texture attributes, and pectic changes in broccoli", Czech Journal of Food Sciences, 2015, Volume 33, Issue 3, p.254 - 260

[0005] The present disclosure addresses, as an example of a problem to be solved, how to improve the texture of frozen broccoli or frozen cauliflower.

[0006] The method for producing frozen broccoli or frozen cauliflower or the method for improving the texture of frozen broccoli or frozen cauliflower according to the present disclosure includes a step of curing the broccoli or cauliflower after harvesting.

[0007] [Method for producing frozen broccoli or frozen cauliflower] The method for producing frozen broccoli or frozen cauliflower according to the present disclosure includes a step of curing harvested broccoli or cauliflower before freezing (hereinafter also simply referred to as "curing step").

[0008] (Broccoli or Cauliflower) In one embodiment, the broccoli or cauliflower used as the raw material may be broccoli or cauliflower harvested on a harvest date when the average temperature for the four days before harvest, including the harvest date, is 20°C or below, 15°C or below, 12°C or below, or 10°C or below. In another embodiment, the broccoli or cauliflower used as the raw material may be broccoli or cauliflower harvested on a harvest date when the average temperature for the four days before harvest, including the harvest date, is 15°C or below, 12°C or below, or 10°C or below. Here, "average temperature" refers to the value obtained by summing the hourly temperatures from 1:00 to 24:00 on a given day and dividing the sum by 24. "The average average temperature for the four days before harvest, including the harvest date" refers to the value obtained by summing the average temperatures for the harvest date, the day before the harvest date, the day before the harvest date, and three days before the harvest date and dividing the sum by 4. Here, depending on the time of harvest on the harvest date, the temperature after harvest will also be used in the above calculation, but the impact that this difference may have on the quality of the broccoli or cauliflower is within a negligible range.

[0009] In one embodiment, the broccoli or cauliflower used as raw material may be broccoli or cauliflower harvested on a harvest date when the average minimum temperature over the four days before harvest, including the harvest date, is 18°C ​​or lower, 15°C or lower, 8°C or lower, 6°C or lower, or 5°C or lower. In another embodiment, the broccoli or cauliflower used as raw material may be broccoli or cauliflower harvested on a harvest date when the average minimum temperature over the four days before harvest, including the harvest date, is 8°C or lower, 6°C or lower, or 5°C or lower. Here, "minimum temperature" refers to the lowest temperature on a given day. "Average minimum temperature over the four days before harvest, including the harvest date" refers to the sum of the minimum temperatures on the harvest date, the day before harvest, the day before harvest, and three days before harvest, divided by four. Here, depending on the time of harvest on the harvest date, the temperature after harvest will also be used in the above calculation, but as with the average temperature, the impact that this difference may have on the quality of the broccoli or cauliflower is negligible.

[0010] In one embodiment, the broccoli or cauliflower used as the raw material may be broccoli or cauliflower harvested in October, November, December, January, February, March, April, or May in Japan. In another embodiment, the broccoli or cauliflower used as the raw material may be broccoli or cauliflower harvested in October, November, December, January, February, or March in Japan. However, the broccoli or cauliflower used as the raw material may be broccoli or cauliflower harvested at other times.

[0011] (Curing) In the present disclosure, "curing" refers to exposing broccoli or cauliflower to an environment at a specific temperature for a specific period of time. Typically, in curing, harvested broccoli or cauliflower is exposed to an environment at a temperature higher than the air temperature at that time (outside air temperature) for a specific period of time. The curing process may be carried out while the broccoli or cauliflower is being transported, or may be carried out while the broccoli or cauliflower is being stored in a fixed location. The curing process may be carried out in several steps, or may be carried out all at once. When the curing process is carried out in several steps, the time described below is the total time. The curing process may be carried out while the broccoli or cauliflower is being left stationary, or may be carried out while the broccoli or cauliflower is being moved. Typically, the curing process is carried out all at once by storing the broccoli or cauliflower in a fixed location while it is being left stationary.

[0012] In the present disclosure, curing refers to leaving harvested broccoli or cauliflower in an environment at a specific temperature for a specific period of time to an extent that the texture can be improved compared to frozen broccoli or frozen cauliflower that is processed from uncured broccoli or cauliflower. The improvement in texture will be described in detail in the section "Method for Improving the Texture of Frozen Broccoli or Frozen Cauliflower" below.

[0013] In the method for producing frozen broccoli or frozen cauliflower of the present disclosure, the combination of temperature (hereinafter also referred to as "curing temperature") and time (hereinafter also referred to as "curing time") in the curing step can be, for example, any of the following (A) to (C): (A) 10°C or higher and lower than 15°C, 75 hours or higher and 200 hours or lower (B) 15°C or higher and lower than 25°C, 5 hours or higher and 150 hours or lower (C) 25°C or higher and lower than 40°C, 2 hours or higher and 100 hours or lower

[0014] The temperature of 10°C or higher but lower than 15°C specified as (A) is slightly higher than 5°C, at which poor growth of broccoli or cauliflower is likely to be observed, and allows curing while minimizing the stress of temperature rise on broccoli or cauliflower grown at lower temperatures. When the combination of curing temperature and curing time is (A) above, the curing time may be 80 hours or more, 90 hours or more, or 100 hours or more. Typically, the longer the curing time, the more likely it is that the texture of the frozen broccoli or cauliflower will be improved.

[0015] Furthermore, when the combination of curing temperature and curing time is (A) above, the curing time may be long enough to avoid problems such as bacterial growth and excessive growth or aging of the broccoli or cauliflower. The curing time may be 180 hours or less, 160 hours or less, or 140 hours or less. Typically, the shorter the curing time, the easier it is to inhibit bacterial growth and excessive growth or aging of the broccoli or cauliflower and to reduce costs.

[0016] The temperature (B) of 15°C or higher but lower than 25°C is a temperature highly suitable for growing broccoli or cauliflower, and allows the physiological functions of broccoli or cauliflower to be exhibited under less stress. When the combination of curing temperature and curing time is (B), the curing time may be 10 hours or longer, 15 hours or longer, 19 hours or longer, or 21 hours or longer. Typically, the longer the curing time, the more likely it is that the texture of the frozen broccoli or cauliflower will be improved.

[0017] Furthermore, when the combination of curing temperature and curing time is (B) above, the curing time may be long enough to avoid problems such as bacterial growth and excessive growth or aging of the broccoli or cauliflower. The curing time may be 130 hours or less, 100 hours or less, 90 hours or less, 80 hours or less, 70 hours or less, 50 hours or less, or 30 hours or less. Typically, the shorter the curing time, the easier it is to suppress bacterial growth and excessive growth or aging of the broccoli or cauliflower and to reduce costs.

[0018] The temperature of 25°C or higher but lower than 40°C specified as (C) is higher than the optimum temperature for broccoli or cauliflower growth, and is expected to be highly effective even for broccoli or cauliflower grown at the optimum temperature for growth. When the combination of curing temperature and curing time is (C) above, the curing time may be 4 hours or more, 5 hours or more, 8 hours or more, 10 hours or more, or 20 hours or more. Typically, the longer the curing time, the more likely it is that the texture of the frozen broccoli or frozen cauliflower will be improved. When the combination of curing temperature and curing time is (C) above, the curing temperature may be 38°C or lower, 36°C or lower, 34°C or lower, or 32°C or lower.

[0019] Furthermore, when the combination of curing temperature and curing time is (C) above, the curing time may be long enough to avoid problems such as bacterial growth and excessive growth or aging of the broccoli or cauliflower. The curing time may be 90 hours or less, 70 hours or less, 50 hours or less, 40 hours or less, or 30 hours or less. Typically, the shorter the curing time, the easier it is to suppress bacterial growth and excessive growth or aging of the broccoli or cauliflower and to reduce costs.

[0020] In one embodiment, the combination of curing temperature and curing time may be (B) above. In this case, the curing temperature may be 15°C or higher, 16°C or higher, 17°C or higher, or 18°C ​​or higher. Typically, when the curing temperature is appropriately high, it is easy to obtain an improved texture of the frozen broccoli or frozen cauliflower and it is easy to keep the curing time short. Furthermore, the curing temperature may be lower than 25°C, 24°C or lower, 23°C or lower, or 22°C or lower. Typically, when the curing temperature is appropriately low, it is easy to suppress bacterial growth and excessive growth or aging of the broccoli or cauliflower.

[0021] In the curing step, the curing temperature and curing time may be determined taking into consideration the value obtained by multiplying the curing temperature (°C) by the curing time (h) (hereinafter also referred to as the "accumulated temperature"). The accumulated temperature may be, for example, 100°C·h or more, 200°C·h or more, 300°C·h or more, or 400°C·h or more. Typically, the larger the accumulated temperature, the more likely it is that the texture of the frozen broccoli or frozen cauliflower will be improved.

[0022] The accumulated temperature may be, for example, 1500°C·h or less, 1200°C·h or less, 1000°C·h or less, or 800°C·h or less. Typically, the smaller the accumulated temperature is, the easier it is to suppress bacterial growth and excessive growth or aging of broccoli or cauliflower, and also to reduce costs.

[0023] The curing step may be performed in the air or under humidified conditions. When the curing step is performed in the air, for example, the temperature of the air in the incubator or temperature-controlled room where the curing step is performed may be set to the above-mentioned curing temperature.

[0024] When the curing step is carried out under humidified conditions, the humidified conditions may be, for example, either (1) or (2) below: (1) bringing broccoli or cauliflower into contact with water; or (2) placing broccoli or cauliflower in a humidified space.

[0025] When the humidification condition is (1) above, the method of bringing broccoli or cauliflower into contact with water may be, for example, the following method (1-1) or (1-2): (1-1) Immersing the cut surface of the stem of broccoli or cauliflower in water; (1-2) Immersing the broccoli or cauliflower in water by, for example, placing the broccoli or cauliflower, or finely divided florets of broccoli or cauliflower, in a water tank.

[0026] When the above method (1-1) is employed, for example, the set temperature of an incubator or thermostatic bath containing water and air may be set to the above-mentioned curing temperature. When the above method (1-2) is employed, for example, the temperature of water may be set to the above-mentioned curing temperature. When the above method (2) is employed, the temperature of humidified air in an incubator or thermostatic room where the curing step is performed may be set to the above-mentioned curing temperature. Note that "humidification" in the above method (2) typically refers to artificially increasing the humidity of the air in the space where the broccoli or cauliflower is present during the curing step by 10% or more relative to the humidity of the atmosphere at that time.

[0027] When the humidification condition is (1) above, the water used may be a nutrient solution containing nutrients. The nutrients may be, for example, fertilizer for hydroponic cultivation.

[0028] When the humidification condition is (1) above, a disinfectant may be added to the water used. Typically, the use of a disinfectant makes it easier to suppress bacterial growth. The disinfectant is not particularly limited as long as it can be used on broccoli or cauliflower, but for example, at least one selected from the group consisting of sodium hypochlorite, hypochlorous acid, sodium chlorite, chlorous acid, peracetic acid, hydrogen peroxide, ethanol, and organic acids can be used. In one embodiment, the disinfectant is sodium hypochlorite or an organic acid. Here, examples of organic acids include carboxylic acids such as acetic acid, citric acid, malic acid, lactic acid, fumaric acid, tartaric acid, succinic acid, and gluconic acid. In one embodiment, the disinfectant is sodium hypochlorite.

[0029] The disinfectant may be used by dissolving in water, dispersing in water, or precipitating in water.

[0030] The curing step may be carried out under light irradiation or in a dark room.

[0031] (Blanching) The method for producing frozen broccoli or cauliflower according to the present disclosure may include a step of blanching the broccoli or cauliflower (hereinafter also referred to simply as the "blanching step"). The blanching step is a step of heating the broccoli or cauliflower before the freezing step described below. The blanching step may be carried out using steam, or by heating in hot water. When heating in hot water, for example, heating may be carried out for 0.5 to 6 minutes in water at 80 to 100°C. The heating time when heating in hot water may be 2 to 5.5 minutes, or may be 3 to 5 minutes.

[0032] In one embodiment, the blanching step is initiated within 4 hours after the end of the curing step. The blanching step may be initiated within 3 hours, 2 hours, 1 hour, or 30 minutes after the end of the curing step. Typically, initiating the blanching step early after the end of the curing step helps to maintain the properties imparted by the curing step and also helps to reduce deterioration of the broccoli or cauliflower.

[0033] (Freezing) The method for producing frozen broccoli or frozen cauliflower according to the present disclosure typically includes a step of freezing broccoli or cauliflower (hereinafter also simply referred to as the "freezing step"). The freezing step is a step of freezing broccoli or cauliflower, which has optionally been subjected to a blanching step, using a freezer or a quick-freezing device. The temperature during the freezing step may be, for example, 0°C or lower, -3°C or lower, -5°C or lower, -10°C or lower, or -20°C or lower.

[0034] In the method for producing frozen broccoli or frozen cauliflower of the present disclosure, when a blanching step is performed, the freezing step may be started within 4 hours, 3 hours, 2 hours, 1 hour, 30 minutes, 20 minutes, or 10 minutes after the end of the blanching step. Typically, starting the freezing step early after the end of the blanching step makes it easier to maintain the properties obtained by the curing and blanching steps and to suppress deterioration of the broccoli or cauliflower.

[0035] In the method for producing frozen broccoli or frozen cauliflower of the present disclosure, if a blanching step is not performed, the freezing step may be started within 4 hours, 3 hours, 2 hours, 1 hour, or 30 minutes after the end of the curing step. Typically, starting the freezing step early after the end of the curing step makes it easier to maintain the properties obtained by the curing step and also makes it easier to suppress deterioration of the broccoli or cauliflower.

[0036] (Frozen Broccoli or Frozen Cauliflower) In the present disclosure, "frozen broccoli" refers to broccoli in which at least a portion of the water contained therein has been frozen. In the present disclosure, "frozen cauliflower" refers to cauliflower in which at least a portion of the water contained therein has been frozen. The temperature of the frozen broccoli or frozen cauliflower may typically be 0°C or lower, -3°C or lower, -5°C or lower, -10°C or lower, or -20°C or lower.

[0037] Frozen broccoli or frozen cauliflower obtained by the method for producing frozen broccoli or frozen cauliflower disclosed herein typically has an improved texture compared to frozen broccoli or frozen cauliflower produced by directly blanching and freezing the broccoli or cauliflower after harvest. One factor contributing to this improved texture may be gene expression, physiological reactions, and / or cellular responses that occur during the curing process. In particular, changes in the expression of genes involved in cell wall biosynthesis may occur. This may result in changes in the components of the cell wall, such as an increase in total pectin content. In particular, the interaction that occurs when the curing process and freezing process are combined may result in new changes. Typically, texture is likely to be improved by changes in the amount of cell wall and the composition of the components that make up the cell wall.

[0038] [Method for Improving the Texture of Frozen Broccoli or Frozen Cauliflower] The present disclosure also provides a method for improving the texture of frozen broccoli or frozen cauliflower, which includes a step of curing harvested broccoli or cauliflower before freezing (curing step).

[0039] Here, "improved texture of frozen broccoli or frozen cauliflower" typically refers to an improvement in texture compared to conventional frozen broccoli or frozen cauliflower in at least one of the following aspects when the frozen broccoli or frozen cauliflower is thawed, cooked as necessary, and eaten: (i) a moderate chewiness (firmness), (ii) a crispness, and (iii) less wateriness.

[0040] Whether the texture of the frozen broccoli or frozen cauliflower has been improved can be relatively easily evaluated from the above viewpoints (i) to (iii) by sensory evaluation, for example, by comparing the taste of conventional frozen broccoli or frozen cauliflower with the frozen broccoli or frozen cauliflower of the present disclosure.

[0041] Whether the texture of frozen broccoli or frozen cauliflower has been improved can also be evaluated by evaluating its physical properties. For example, the above-mentioned (i) moderate chewiness (hardness) and (ii) crispness can be evaluated by measuring the maximum load as follows. A large measured maximum load value is considered to correspond to excellent chewiness and crispness when eaten.

[0042] Whether the texture of the frozen broccoli or cauliflower has been improved may be evaluated by the extent to which the maximum load has changed compared to frozen broccoli or cauliflower produced without a curing process, i.e., the percentage change in maximum load (%). The percentage change in maximum load may be 110% or more, 120% or more, 140% or more, 180% or more, or 200% or more. A larger percentage change indicates a greater degree of texture improvement.

[0043] The maximum load is measured by, for example, placing 9 g of naturally thawed stems, which have been diced with a knife so that each side is within the range of 3 to 5 mm, into a cylindrical Petri dish (manufactured by Taketomo Electric Co., Ltd.) with an outer diameter (external dimensions) of 42 mm and a height of 13.5 mm (inner diameter (internal dimensions) of 39 mm and a height of 12 mm (all actual measurements)), and compressing it with a puncture probe (flat type) (manufactured by Taketomo Electric Co., Ltd.) with a diameter of 36 mm at a compression speed of 1 mm / s and a compression ratio of 40%. The maximum load can be measured using, for example, a "Tensipresser TTP-50BXII" manufactured by Taketomo Electric Co., Ltd. Note that depending on the device, the maximum load may be expressed as "gw (or gf) / cm ２ ", for example, 1000 gw (gf) / cm ２ When measured, the maximum load is 1000 gw (gf) / cm ２ x 10.1788 cm ２ × 0.0098N / gw(gf) = 99.7522N, and the determination can be made by converting it to N. ２ is the measurement area of ​​a 36 mm diameter probe, and 0.0098 N / gw(gf) is the conversion rate from gw(gf) to N.

[0044] The above (iii) low wateriness can be evaluated, for example, by analyzing the amount of dripping as follows: A small amount of dripping is considered to correspond to a low wateriness when eaten.

[0045] The amount of dripping can be evaluated by, for example, placing 2-3 g of a sample of stems diced (cut into roughly cubes) with a knife to a side of 3-5 mm on filter paper, centrifuging the sample at room temperature for 6 minutes at an RCF of 300 (×g), and calculating the ratio of the water content on the filter paper and the water content remaining in the centrifuge tube to the mass of the sample before centrifugation. Examples of centrifuges that can be used include the "Universal Refrigerated Centrifuge Model 5922" manufactured by Kubota Shoji Co., Ltd.

[0046] In one embodiment, the method for improving the texture of frozen broccoli or frozen cauliflower of the present disclosure may be a method for improving the texture of broccoli or cauliflower harvested on a harvest date when the average of the average temperature over the four days before harvest, including the harvest date, is 20° C. or less, 15° C. or less, 12° C. or less, or 10° C. or less. In another embodiment, the method for improving the texture of frozen broccoli or frozen cauliflower of the present disclosure may be a method for improving the texture of broccoli or cauliflower harvested on a harvest date when the average of the average temperature over the four days before harvest, including the harvest date, is 15° C. or less, 12° C. or less, or 10° C. or less. Here, with regard to "average temperature," please refer to the definition explained in the section regarding the method for producing frozen broccoli or frozen cauliflower above.

[0047] In one embodiment, the method for improving the texture of frozen broccoli or frozen cauliflower of the present disclosure may be a method for improving the texture of broccoli or cauliflower harvested on a harvest date when the average minimum temperature during the four days before harvest, including the harvest date, is 18° C. or less, 15° C. or less, 8° C. or less, 6° C. or less, or 5° C. or less. In another embodiment, the method for improving the texture of frozen broccoli or frozen cauliflower of the present disclosure may be a method for improving the texture of broccoli or cauliflower harvested on a harvest date when the average minimum temperature during the four days before harvest, including the harvest date, is 8° C. or less, 6° C. or less, or 5° C. or less. Here, with regard to the "minimum temperature," please refer to the definition explained in the section regarding the method for producing frozen broccoli or frozen cauliflower above.

[0048] In one embodiment, the method for improving the texture of frozen broccoli or frozen cauliflower of the present disclosure may be a method for improving the texture of broccoli or cauliflower harvested in October, November, December, January, February, March, April, or May in Japan. In another embodiment, the method for improving the texture of frozen broccoli or frozen cauliflower of the present disclosure may be a method for improving the texture of broccoli or cauliflower harvested in October, November, December, January, February, or March in Japan. However, the method for improving the texture of frozen broccoli or frozen cauliflower of the present disclosure may also be a method for improving the texture of broccoli or cauliflower harvested at other times.

[0049] (Curing, Blanching, and Freezing) In the curing step, the conditions described above in the section about the method for producing frozen broccoli or frozen cauliflower can be used. The method for improving the texture of frozen broccoli or frozen cauliflower of the present disclosure may include a step of blanching the broccoli or cauliflower (blanching step) and a step of freezing the broccoli or cauliflower (freezing step). In the blanching step and the freezing step, the conditions described above in the section about the method for producing frozen broccoli or frozen cauliflower can be used.

[0050] [Frozen Broccoli] This specification also newly discloses frozen broccoli having a total pectin content of 11.0% by mass or more. The total pectin content of the frozen broccoli may be 11.4% by mass or more, 11.8% by mass or more, 12.2% by mass or more, 12.6% by mass or more, 13.0% by mass or more, 13.4% by mass or more, or 13.8% by mass or more. Such frozen broccoli is obtained by the manufacturing method or texture improving method disclosed herein.

[0051] Furthermore, the frozen broccoli according to the present disclosure may have a total pectin content of less than 11.0% by mass, less than 10.6% by mass, or less than 10.4% by mass. Even when the total pectin content of the raw material broccoli is less than 11.0% by mass, the production method or texture improving method according to the present disclosure makes it easier to obtain frozen broccoli having the above-mentioned total pectin content.

[0052] In one embodiment, the raw broccoli may be broccoli harvested on a harvest date when the average temperature for the four days before harvest, including the harvest date, is 20°C or lower, 15°C or lower, 12°C or lower, or 10°C or lower. In another embodiment, the raw broccoli may be broccoli harvested on a harvest date when the average temperature for the four days before harvest, including the harvest date, is 15°C or lower, 12°C or lower, or 10°C or lower. In another embodiment, the raw broccoli may be broccoli harvested on a harvest date when the average minimum temperature for the four days before harvest, including the harvest date, is 18°C ​​or lower, 15°C or lower, 8°C or lower, 6°C or lower, or 5°C or lower. In another embodiment, the raw broccoli may be broccoli harvested on a harvest date when the average minimum temperature for the four days before harvest, including the harvest date, is 8°C or lower, 6°C or lower, or 5°C or lower. Such raw broccoli typically tends to have a low total pectin content, but the production method or texture improvement method of the present disclosure makes it easier to obtain frozen broccoli having the above-mentioned total pectin content. In one embodiment, the starting broccoli may be broccoli or cauliflower harvested in October, November, December, January, February, March, April, or May in Japan. In another embodiment, the starting broccoli may be broccoli or cauliflower harvested in October, November, December, January, February, or March in Japan.

[0053] In this specification, each specific feature described in one embodiment relating to each aspect of the present disclosure may be combined in any manner to form a new embodiment, and it should be understood that such a new embodiment may also be included in each aspect of the present disclosure.

[0054] The present disclosure will be explained in more detail below with reference to examples, but the present disclosure is not limited to these examples.

[0055] Broccoli Study 1 [Production of Frozen Broccoli] (Procurement of Broccoli) Broccoli varieties 1 to 4 shown in Table 1 below were obtained in multiple plants. All broccoli was harvested within five days of the date of acquisition, on a harvest date when the average temperature in the four days before harvest, including the harvest date, was 10°C or below, and on a harvest date when the average minimum temperature in the four days before harvest, including the harvest date, was 5°C or below.

[0056]

[0057] (Curing step) The broccoli used in each example is shown in Table 2. For each example, 4 to 6 strains of broccoli were used.

[0058] In Examples 1-1 to 1-6, 2-2, 2-3, and 2-6 to 2-11, curing was performed with the cut surface of the broccoli stem immersed in tap water using an incubator (Yamato Scientific Co., Ltd., low-temperature incubator IN604) set to the temperature shown in Table 2 for the time shown in Table 2. Because the cut surface of the broccoli may have dried out or the tissue on the cut surface may have aged, about 1 cm of the cut surface of the broccoli was cut off to obtain a fresh cut surface, which was then subjected to curing.

[0059] In Examples 1-7, 1-8, and 2-12, an incubator (Yamato Scientific Co., Ltd., Low-Temperature Incubator IN604) set to the temperature shown in Table 2 was used, and the cut surface of the broccoli stem was immersed in the nutrient solution and cured for the time shown in Table 2. The nutrient solution used was a 1:1 mixture of a nutrient solution prepared using OAT House No. 1 (Otsuka Agritechno Co., Ltd.) with Formulation A (1500 g / L) and a nutrient solution prepared using OAT House No. 2 (Otsuka Agritechno Co., Ltd.) with Formulation A (1000 g / L), diluted with tap water, adjusted to an EC value of 1.6 dS / m, and adjusted to a pH of 6.5 to 6.6 with a pH adjuster for hydroponic cultivation. In Example 1-8, lighting (Olympia Lighting Co., Ltd., LED System RCL1245) was used, and PPFD 200 to 250 μmol / m ２Curing was carried out while irradiating light under the conditions of 1 / s and a photoperiod of 16 h / day. In all examples except for Example 1-8, curing was carried out in a dark place.

[0060] In Examples 1-9 and 2-13, the broccoli was placed in an incubator (Yamato Scientific Co., Ltd., low-temperature incubator IN604) set at the temperature shown in Table 2, and curing was carried out in the air for the time shown in Table 2.

[0061] After curing, each broccoli was promptly processed into frozen broccoli according to the procedure described below. In addition, in Examples 2-1, 2-4, and 2-5, no curing was performed, and the broccoli was processed into frozen broccoli according to the procedure described below on the same day it was obtained.

[0062]

[0063] (Cutting step) Each broccoli was cut into florets, and the stem length of all samples was adjusted to 30 to 40 mm and the diameter of the stem to 10 mm or less. A portion of the cut samples was used for the subsequent measurement of water content, and the remaining portion was subjected to the subsequent blanching step.

[0064] (Blanching step) Each 200 g portion of the cut sample was boiled in approximately 5 L of hot water (90°C) for 4 minutes, and immediately cooled in ice water for 4 minutes after heating. After cooling, the sample was subjected to the subsequent freezing step. The blanching step was started within 60 minutes after the end of the curing step.

[0065] (Freezing process and packaging process) Excess water on the surface of each sample was removed with kitchen paper, and the sample was frozen at −25° C. for 1 hour using a quick freezer (manufactured by Maekawa Manufacturing Co., Ltd.). Each frozen sample was placed in a polyethylene bag and stored at −25° C. The freezing process was started within 30 minutes after the end of the blanching process.

[0066] [Various Analyses] (Moisture Content) The moisture content of raw broccoli and frozen broccoli was measured using the following procedure. For raw broccoli, broccoli was cut into small florets, which were then separated into florets and stems, and only the stems were used for measurement. The stems were finely cut with a knife. 3 g of the cut sample was collected in an aluminum foil cup and placed in a dryer (Yamato Scientific Co., Ltd., Constant Temperature Dryer DX300) set at 105°C for 3 hours. The moisture content of the sample was calculated by comparing the mass before and after drying. For frozen broccoli, each sample was placed in a pouch and thawed under running water. In the partially thawed state, the florets and stems were separated, and only the stems were used for measurement. Measurement was then performed in the same manner as for raw broccoli.

[0067] (Yield) The mass (W1) of broccoli was measured before being subjected to the curing process. After the mass measurement, the broccoli was subjected to the curing process. After curing, excess water droplets on the broccoli were quickly wiped off, and the mass (W2) was measured. The yield was calculated using the following formula. Four broccoli plants were measured for each example, and the average value was obtained. Yield (%) = {(W2 - W1) / W1} x 100 W1: Mass (g) of broccoli before curing W2: Mass (g) of broccoli after curing

[0068] (Maximum Load) The maximum load was analyzed at room temperature (22±2°C). The frozen samples were thawed naturally for 3 to 4 hours before use. The maximum load was measured using a texture measuring instrument (Taketomo Electric Co., Ltd., Tensipressor TTP-50BXII). Each sample was separated into buds and stems, and only the stems were used for measurement. The stems were diced (cut into roughly cubes) with a knife so that each side was within the range of 3 to 5 mm, and 9 g was placed in a cylindrical Petri dish (Taketomo Electric Co., Ltd.) with an outer diameter (external dimensions) of 42 mm and a height of 13.5 mm (internal diameter (internal dimensions) of 39 mm and a height of 12 mm (both actual measurements)), and the height was adjusted to be uniform. Using a 36 mm diameter flat puncture probe (manufactured by Taketomo Electric Co., Ltd.), the maximum load was measured when the dice-shaped samples in a petri dish were compressed at a compression speed of 1 mm / s and a compression ratio of 40%. Each sample was measured three times. The maximum load is considered to be an index corresponding to the firmness (chewiness) and crunchiness of the broccoli.

[0069] (Rate of change in maximum load) The rate of change in maximum load was calculated by the following formula: Rate of change in maximum load (%) = Maximum load of each sample after curing / Maximum load of sample prepared without curing

[0070] (Drip Amount) Drip amount analysis was performed at room temperature (22±2°C). Frozen samples were allowed to thaw naturally for 3-4 hours before use. Each sample was separated into florets and stems, and only the stems were used for measurement. Measurements were performed using a centrifuge (Universal Refrigerated Centrifuge Model 5922, manufactured by Kubota Shoji Co., Ltd.). Stems were diced (cut into roughly cubes) with a knife to a side length of 3-5 mm. 2-3 g of the sample was placed on filter paper and centrifuged for 6 minutes at room temperature under an RCF of 300 (×g). The moisture adhering to the filter paper and the moisture remaining in the centrifuge tube were considered the drip amount, and the ratio of this to the mass of the sample before centrifugation was calculated. Each sample was measured three times, and the average value was obtained. The drip amount is considered to be an indicator of the wateriness of broccoli.

[0071] (Alcohol-Insoluble Solids (AIS)) Analysis of AIS was performed at room temperature (22±2°C). Broccoli was thawed under running water until semi-thawed before use. AIS was extracted according to the method disclosed by Christiaens et al. in "Towards a Better Understanding of the Pectin Structure-Function Relationship in Broccoli During Processing: Part I - Macroscopic and Molecular Analyses," Food Research International, July 2011, Volume 44, Issue 6, pp. 1604-1612. Specifically, each sample that had undergone a freezing process was placed in a pouch and thawed under running water. The semi-thawed sample was separated into florets and stems, and only the stems were used for analysis. 15 g of finely cut stems were weighed, 96 mL of 99.5% ethanol was added, and the mixture was homogenized at 10,000 rpm for 30 seconds using a homogenizer (Nippon Seiki Seisakusho, AM-3). After crushing, the mixture was filtered by suction using filter paper (No. 2, manufactured by Advantec Toyo Co., Ltd.), and the residue was collected. 48 mL of 99.5% ethanol was added again and homogenized in the same manner. The residue was collected again by suction filtration, and then 48 mL of acetone was added and homogenized in the same manner. The residue collected by suction filtration was dried overnight using a thermostatic dryer (DX300, manufactured by Yamato Scientific Co., Ltd.) at 40 ° C., and the mass was measured. Although the above literature states that 95% ethanol was used, 99.5% ethanol was used in this measurement.

[0072] The amount of AIS in the sample (wet basis (w.b.)) was calculated using the following formula: AIS (w.b.) (g / 100g) = W4 / W3 x 100, where W3 is the mass (g) of the sample (finely cut stems) and W4 is the mass (g) of AIS dried overnight.

[0073] The amount of AIS per dry mass (dry basis (d.b.)) was calculated using the following formula: AIS (d.b.) (g / 100g) = {AIS (w.b.) / (100-MC)} x 100, where MC is the moisture content (%) of the frozen broccoli.

[0074] (Extraction of Total Pectin) Total pectin was extracted according to the method disclosed by Melton et al. in "Determination of the Uronic Acid Content of Plant Cell Walls Using a Colorimetric Assay," Current Protocols in Food Analytical Chemistry, August 2001, pp. E3.3.1-E3.3.4. Specifically, 10 mg of dried AIS was placed in a screw-cap test tube, a stir bar was inserted, 1 mL of concentrated sulfuric acid was added, and the tube was capped. The test tube was placed in ice water, and the contents were stirred for 5 minutes. 1 mL of concentrated sulfuric acid was added, and the tube was stirred on ice water for 5 minutes. 0.5 mL of distilled water was added, and the tube was stirred on ice water for 5 minutes. 0.5 mL of distilled water was added again, and the tube was stirred on ice water for 5 minutes. 7 mL of distilled water was added, and the tube was stirred in a vortex mixer for 30 seconds, followed by centrifugation at 2000 g for 10 minutes. The supernatant was used as the total pectin extract.

[0075] (Extraction of Water-Soluble Pectin (WSP)) WSP was extracted from each sample after the freezing process according to the method disclosed by Christiaens et al. in "Towards a Better Understanding of the Pectin Structure-Function Relationship in Broccoli During Processing: Part I - Macroscopic and Molecular Analyses," Food Research International, July 2011, Volume 44, Issue 6, pp. 1604-1612. Specifically, 250 mg of dried AIS was added to an Erlenmeyer flask, followed by the addition of 45 mL of distilled water and heating at 90-95°C for 5 minutes. After heating, the mixture was cooled in ice water for 10 minutes. The sample was filtered using filter paper (No. 5A, manufactured by Advantec Toyo Co., Ltd.), and distilled water was added to the supernatant to make a final volume of 50 mL (preparation of WSP extract).

[0076] (Measurement of WSP content and total pectin content) The WSP content or total pectin content was measured according to the method disclosed by Melton et al. in "Determination of the uronic acid content of plant cell walls using a colorimetric assay," Current Protocols in Food Analytical Chemistry, August 2001, pp. E3.3.1-E3.3.4. Specifically, 400 μL of WSP extract or total pectin extract was mixed with 40 μL of 4 M sulfamic acid / potassium sulfamate solution (pH 1.6). 2.4 mL of concentrated sulfuric acid containing 75 mM sodium tetraborate was added and further mixed. The mixture was heated in a boiling water bath for 20 minutes, and immediately cooled in ice water for 10 minutes after the reaction was completed. 80 μL of 1.5 g / L m-hydroxydiphenyl was added as a color reagent, and after standing for 10 minutes, the absorbance at 525 nm was measured using an absorbance microplate reader (Multiskan SkyHigh, manufactured by Thermo Fisher Scientific). The same procedure was performed using distilled water as a blank sample, and a 0.5% (w / v) aqueous sodium hydroxide solution was added as a control sample instead of the color reagent, and the absorbance obtained for each sample was subtracted. A calibration curve was drawn from a standard substance containing a known concentration of galacturonic acid, and the amount of WSP (wet basis (w.b.)) or total pectin (% dry basis) in the sample was determined in terms of galacturonic acid equivalent (mg / 100 mg AIS). The amount of WSP was calculated using the following formula: WSP (wet basis (w.b.)) = A x B / 100, where A = galacturonic acid equivalent (mg / 100 mg AIS), B = AIS (wet basis (w.b.)). The amount of total pectin was calculated using the following formula: Total pectin (% dry basis (d.b.)) = [(A x B / 100) / (100 - C)] x 100, where A = galacturonic acid equivalent (mg / 100 mg AIS), B = AIS (wet basis (w.b.), C = moisture content of frozen broccoli (w.b.).

[0077] (Calcium ions) Frozen broccoli sealed in a polyethylene bag was thawed under running water. The florets and stems were separated while still partially thawed, and only the stems were used for measurement. The sample was finely cut and further pulverized using a mill mixer (Yamazen Corporation, MR-280(W)). The sample was filtered using a stocking-type net and further centrifuged at 8,000 rpm and room temperature (25°C) for 20 minutes using a centrifuge (Kubota Shoji Co., Ltd., Universal Refrigerated Centrifuge Model 5922). The calcium ion concentration of the supernatant was measured using a compact calcium ion meter (HORIBA Advanced Techno Co., Ltd., LAQUAtwin Ca-11).

[0078] The results of each analysis are shown in Tables 3 to 6.

[0079]

[0080]

[0081]

[0082]

[0083] As can be seen from the results in Table 3, when the curing time was uniformly set at 72 hours, a significant increase in maximum load and a significant decrease in drip amount were observed when the curing temperature was 20° C. compared to when the curing temperature was 2° C. or 10° C. The increase in maximum load is thought to contribute to an improvement in the chewiness and crispness when eaten, and the decrease in drip amount is thought to contribute to a reduction in wateriness when eaten.

[0084] As can be seen from the results in Table 4, when the curing temperature was 20° C. or 30° C., a significant increase in maximum load was observed over various times. In either case, it was suggested that the longer the curing time within an appropriate range, the more likely the maximum load was to increase, and that the higher the curing temperature within an appropriate range, the more likely the maximum load was to increase in a shorter time.

[0085] As can be seen from the results in Table 5, when the curing temperature was 5°C, no increase in maximum load or decrease in drip amount was observed even when the curing time was 120 hours, and extending the curing time to 216 hours did not result in any improvement. When the curing temperature was 10°C, a significant increase in maximum load was observed when the curing time was 120 hours compared to when the curing time was 72 hours (Example 2-3, Table 3). On the other hand, when the curing time was further extended to 216 hours, a decrease in maximum load and an increase in drip amount were observed. This may be due to the fact that excessively long curing times facilitate bacterial growth and broccoli aging. Furthermore, when the curing temperature was 40°C or higher, a decrease in maximum load and an increase in drip amount were observed. This may be due to the fact that excessively high curing temperatures facilitate bacterial growth and broccoli aging, and that conditions similar to low-temperature cooking make the broccoli more susceptible to denaturation. However, the growth of bacteria may be suppressed by adding a disinfectant to the water, which may allow for higher curing temperatures or longer curing times.

[0086] As can be seen from the results in Table 6, when a nutrient solution was used in the curing process, a significant increase in maximum load and a significant decrease in drip amount were observed when the curing temperature was 20° C. Similarly, when light was irradiated in the curing process, a similar significant increase in maximum load and a significant decrease in drip amount were observed.

[0087] In all cases, the AIS content on a wet basis ranged from 4.3 to 6.5 g / 100 g, the AIS content on a dry basis ranged from 55.0 to 69.4 g / 100 g, the WSP content from 54.0 to 137.1 mg / 100 g, and the calcium ion concentration from 25 to 36 ppm, all of which were within the typical ranges for the amounts of each component in broccoli. The yields of the cured samples ranged from 7.1 to 24.0%. Overall, the curing process tended to increase yield, increase AIS content, especially on a dry basis, and decrease WSP content. This suggests that the curing process induces growth and cell division in the broccoli, resulting in changes in the amount or composition of the cell wall.

[0088] [Sensory Evaluation] The frozen samples of Examples 1-9 and 2-13 were naturally thawed for 4 hours and then subjected to a sensory evaluation of hardness, crispness, and wateriness. The sensory evaluation was performed by eight trained expert panelists.

[0089] (Hardness) The sample of Example 1-9 was compared with the sample of Example 2-13 and rated as a if it was harder, b if it was about the same, or c if it was softer.

[0090] (Crunchy Feeling) The sample of Example 1-9 was compared with the sample of Example 2-13 and rated as a if the crunchy feel was strong, b if the crunchy feel was the same, or c if the crunchy feel was weak.

[0091] (Wateriness) The sample of Example 1-9 was compared with the sample of Example 2-13 and rated as a if it was less watery, b if it was about the same, or c if it was very watery.

[0092] The results of the sensory evaluation are shown in Table 7.

[0093]

[0094] The above results demonstrate that the texture of broccoli is actually improved by undergoing a curing process.

[0095] Broccoli Study 2 [Production of Frozen Broccoli] (Procurement of Broccoli) Broccoli varieties 5 to 7 shown in Table 8 below were obtained in multiple plants. All broccoli varieties were harvested within five days of the date of acquisition. Broccoli varieties 5 and 6 were harvested on a harvest date when the average temperature for the four days before harvest, including the harvest date, was 10°C or lower, and when the average minimum temperature for the four days before harvest, including the harvest date, was 5°C or lower. Broccoli 7 was harvested on a harvest date when the average temperature for the four days before harvest, including the harvest date, was 15°C or higher, and when the average minimum temperature for the four days before harvest, including the harvest date, was 10°C or higher.

[0096]

[0097] (Curing step) The broccoli used in each example is shown in Table 9. For each example, 4 to 6 strains of broccoli were used.

[0098] In Examples 3-4 to 3-6, broccoli stems were cured for the time shown in Table 9 with the cut surfaces immersed in tap water using an incubator (Yamato Scientific Co., Ltd., Low-Temperature Incubator IN604) set to the temperature shown in Table 9. Because the cut surfaces of the broccoli may have dried out or the tissue on the cut surfaces may have aged, approximately 1 cm of the cut surface of the broccoli was cut off to obtain fresh cut surfaces for curing. After curing, each broccoli was immediately subjected to the cutting, blanching, freezing, and packaging processes in the same manner as in Study 1.

[0099] In addition, in Examples 3-1 to 3-3, no curing was performed, and the broccoli was subjected to the cutting, blanching, freezing and packaging steps in the same procedures as in Study 1 on the same day it was obtained.

[0100]

[0101] For each sample, the maximum load, the rate of change in maximum load, and the total pectin content were evaluated using the same procedures as in Study 1. The results of each analysis are shown in Table 10.

[0102]

[0103] As can be seen from the results in Table 10, curing increased the maximum load and the total pectin content. In particular, even when the total pectin content of the raw broccoli (corresponding to Examples 3-4 to 3-6) was less than 11.0% by mass, curing was found to increase the total pectin content to 11.0% by mass or more. Furthermore, the increase in total pectin content was significant in broccoli harvested on a harvest date when the average mean temperature for the four days before harvest, including the harvest date, was 10°C or lower and the average minimum temperature for the four days before harvest, including the harvest date, was 5°C or lower. This indicates that curing is highly effective in increasing the total pectin content in, for example, autumn-winter broccoli.

[0104] - Study on cauliflower [Production of frozen cauliflower] (Procurement of cauliflower) Multiple plants of each of cauliflowers 1 to 3 shown in Table 11 below were obtained. All cauliflowers were harvested within five days of the date of acquisition, on a harvest date when the average temperature in the four days before harvest, including the harvest date, was 10°C or lower, and on a harvest date when the average minimum temperature in the four days before harvest, including the harvest date, was 5°C or lower.

[0105]

[0106] (Curing step) The cauliflower used in each example is shown in Table 12. For each example, 4 to 6 cauliflower plants were used.

[0107] In Examples 4-2, 4-5, and 4-7, curing was performed for the time shown in Table 12 with the cut surface of the cauliflower stalk immersed in tap water using an incubator (Yamato Scientific Co., Ltd., low-temperature incubator IN604) set to the temperature shown in Table 12. Because the cut surface of the cauliflower may have dried or the tissue on the cut surface may have aged, approximately 1 cm of the cut surface of the cauliflower was cut off to obtain a fresh cross section, which was then subjected to curing. After curing, each cauliflower was immediately subjected to the cutting, blanching, freezing, and packaging steps in the same manner as for broccoli.

[0108] In Example 4-4, cauliflower was placed in an incubator (Yamato Scientific Co., Ltd., low-temperature incubator IN604) set at the temperature shown in Table 12, and cured in the air for the time shown in Table 12. After curing, the cauliflower was immediately subjected to the cutting, blanching, freezing, and packaging steps in the same manner as for broccoli.

[0109] In addition, in Examples 4-1, 4-3, and 4-6, no curing was performed, and the cauliflower was subjected to the cutting, blanching, freezing, and packaging steps in the same manner as for broccoli on the same day it was obtained.

[0110]

[0111] For each sample, the moisture content, maximum load, and rate of change in maximum load were evaluated using the same procedures as for broccoli. The analytical results are shown in Table 13.

[0112]

[0113] When cauliflower was used, the maximum load increased by curing, as in the case of broccoli. Therefore, it was demonstrated that the texture of cauliflower can also be improved by the method of the present disclosure.

[0114] Illustrative embodiments of the present disclosure are described below. [1] A method for producing frozen broccoli or cauliflower, comprising a step of curing harvested broccoli or cauliflower before freezing. [2] The method for producing frozen broccoli or cauliflower according to [1], wherein the curing is performed so that the rate of change in maximum load of the frozen broccoli or cauliflower is 110% or more. [3] The method for producing frozen broccoli or cauliflower according to [1], wherein the curing is performed so that the rate of change in maximum load of the frozen broccoli or cauliflower is 120% or more. [4] The method for producing frozen broccoli or cauliflower according to [1], wherein the curing is performed so that the rate of change in maximum load of the frozen broccoli or cauliflower is 140% or more. [5] The method for producing frozen broccoli or cauliflower according to [1], wherein the curing is performed so that the rate of change in maximum load of the frozen broccoli or cauliflower is 180% or more. [6] The method for producing frozen broccoli or cauliflower according to [1], wherein the curing is performed so that the rate of change in maximum load of the frozen broccoli or cauliflower is 200% or more.

[0115] [7] The manufacturing method of any one of [1] to [6], wherein the combination of temperature and time in the curing is any one of the following [A] to [C]: [A] 10°C or higher but lower than 15°C, 75 hours or higher but lower than 200 hours; [B] 15°C or higher but lower than 25°C, 5 hours or higher but lower than 150 hours; [C] 25°C or higher but lower than 40°C, 2 hours or higher but lower than 100 hours.

[0116] [8] The manufacturing method of [7], wherein the combination of temperature and time in the curing is [A] above and the curing time is 80 hours or more. [9] The manufacturing method of [7], wherein the combination of temperature and time in the curing is [A] above and the curing time is 90 hours or more.

[10] The manufacturing method of [7], wherein the combination of temperature and time in the curing is [A] above and the curing time is 100 hours or more.

[0117]

[11] The manufacturing method of any one of [7] to

[10] , wherein the combination of temperature and time in the curing is [A] above and the curing time is 180 hours or less.

[12] The manufacturing method of any one of [7] to

[10] , wherein the combination of temperature and time in the curing is [A] above and the curing time is 160 hours or less.

[13] The manufacturing method of any one of [7] to

[10] , wherein the combination of temperature and time in the curing is [A] above and the curing time is 140 hours or less.

[0118]

[14] The manufacturing method of [7], wherein the combination of temperature and time in the curing is [B] above, and the curing time is 10 hours or more.

[15] The manufacturing method of [7], wherein the combination of temperature and time in the curing is [B] above, and the curing time is 15 hours or more.

[16] The manufacturing method of [7], wherein the combination of temperature and time in the curing is [B] above, and the curing time is 19 hours or more.

[17] The manufacturing method of [7], wherein the combination of temperature and time in the curing is [B] above, and the curing time is 21 hours or more.

[0119]

[18] The manufacturing method of any one of [7] and

[14] to

[17] , wherein the combination of temperature and time in the curing is [B] above, and the curing time is 130 hours or less.

[19] The manufacturing method of any one of [7] and

[14] to

[17] , wherein the combination of temperature and time in the curing is [B] above, and the curing time is 100 hours or less.

[20] The manufacturing method of any one of [7] and

[14] to

[17] , wherein the combination of temperature and time in the curing is [B] above, and the curing time is 90 hours or less.

[21] The manufacturing method of any one of [7] and

[14] to

[17] , wherein the combination of temperature and time in the curing is [B] above, and the curing time is 80 hours or less.

[22] The manufacturing method of any one of [7] and

[14] to

[17] , wherein the combination of temperature and time in the curing is [B] above, and the curing time is 70 hours or less.

[23] The manufacturing method of any one of [7] and

[14] to

[17] , wherein the combination of temperature and time in the curing is [B] above and the curing time is 50 hours or less.

[24] The manufacturing method of any one of [7] and

[14] to

[17] , wherein the combination of temperature and time in the curing is [B] above and the curing time is 30 hours or less.

[0120]

[25] The manufacturing method of any one of [7] and

[14] to

[24] , wherein the combination of temperature and time in the curing is [B] above, and the curing temperature is 16°C or higher.

[26] The manufacturing method of any one of [7] and

[14] to

[24] , wherein the combination of temperature and time in the curing is [B] above, and the curing temperature is 17°C or higher.

[27] The manufacturing method of any one of [7] and

[14] to

[24] , wherein the combination of temperature and time in the curing is [B] above, and the curing temperature is 18°C ​​or higher.

[0121]

[28] The manufacturing method of any one of [7] and

[14] to

[27] , wherein the combination of temperature and time in the curing is [B] above, and the temperature in the curing is 24° C. or less.

[29] The manufacturing method of any one of [7] and

[14] to

[27] , wherein the combination of temperature and time in the curing is [B] above, and the temperature in the curing is 23° C. or less.

[30] The manufacturing method of any one of [7] and

[14] to

[27] , wherein the combination of temperature and time in the curing is [B] above, and the temperature in the curing is 22° C. or less.

[0122]

[31] The manufacturing method of [7], wherein the combination of temperature and time in the curing is [C] above, and the curing time is 4 hours or more.

[32] The manufacturing method of [7], wherein the combination of temperature and time in the curing is [C] above, and the curing time is 5 hours or more.

[33] The manufacturing method of [7], wherein the combination of temperature and time in the curing is [C] above, and the curing time is 8 hours or more.

[34] The manufacturing method of [7], wherein the combination of temperature and time in the curing is [C] above, and the curing time is 10 hours or more.

[35] The manufacturing method of [7], wherein the combination of temperature and time in the curing is [C] above, and the curing time is 20 hours or more.

[0123]

[36] The manufacturing method of any one of [7] and

[31] to

[35] , wherein the combination of temperature and time in the curing is [C] above, and the curing time is 90 hours or less.

[37] The manufacturing method of any one of [7] and

[31] to

[35] , wherein the combination of temperature and time in the curing is [C] above, and the curing time is 70 hours or less.

[38] The manufacturing method of any one of [7] and

[31] to

[35] , wherein the combination of temperature and time in the curing is [C] above, and the curing time is 50 hours or less.

[39] The manufacturing method of any one of [7] and

[31] to

[35] , wherein the combination of temperature and time in the curing is [C] above, and the curing time is 40 hours or less.

[40] The manufacturing method of any one of [7] and

[31] to

[35] , wherein the combination of temperature and time in the curing is [C] above, and the curing time is 30 hours or less.

[0124]

[41] The manufacturing method of any one of [7] and

[31] to

[40] , wherein the combination of temperature and time in the curing is [C] above, and the curing temperature is 38°C or less.

[42] The manufacturing method of any one of [7] and

[31] to

[40] , wherein the combination of temperature and time in the curing is [C] above, and the curing temperature is 36°C or less.

[43] The manufacturing method of any one of [7] and

[31] to

[40] , wherein the combination of temperature and time in the curing is [C] above, and the curing temperature is 34°C or less.

[44] The manufacturing method of any one of [7] and

[31] to

[40] , wherein the combination of temperature and time in the curing is [C] above, and the curing temperature is 32°C or less.

[0125]

[45] The manufacturing method of any of [1] to

[44] , using broccoli or cauliflower harvested on a harvesting day when the average temperature during the four days before harvesting, including the harvesting day, is 15°C or below.

[46] The manufacturing method of any of [1] to

[44] , using broccoli or cauliflower harvested on a harvesting day when the average temperature during the four days before harvesting, including the harvesting day, is 12°C or below.

[47] The manufacturing method of any of [1] to

[44] , using broccoli or cauliflower harvested on a harvesting day when the average temperature during the four days before harvesting, including the harvesting day, is 10°C or below.

[48] The manufacturing method of any of [1] to

[47] , using broccoli or cauliflower harvested on a harvesting day when the average minimum temperature during the four days before harvesting, including the harvesting day, is 8°C or below.

[49] The manufacturing method of any of [1] to

[47] , using broccoli or cauliflower harvested on a harvesting day when the average minimum temperature during the four days before harvesting, including the harvesting day, is 6°C or below.

[50] The manufacturing method of any one of [1] to

[47] , which uses broccoli or cauliflower harvested on a harvesting day when the average minimum temperature for the four days before harvesting, including the harvesting day, is 5° C. or less.

[51] The manufacturing method of any one of [1] to

[50] , which uses broccoli or cauliflower harvested in Japan in October, November, December, January, February, March, April, or May.

[0126]

[52] The manufacturing method of any of [1] to

[51] , wherein the curing is carried out under atmospheric conditions.

[53] The manufacturing method of any of [1] to

[52] , wherein the curing is carried out under humidified conditions.

[54] The manufacturing method of

[53] , wherein the humidified conditions are either (1) or (2) below: (1) contacting broccoli or cauliflower with water; or (2) placing broccoli or cauliflower in a humidified space.

[55] The manufacturing method of

[53] or

[54] , wherein broccoli or cauliflower is brought into contact with water, and a disinfectant is coexistent in the water.

[56] The manufacturing method of

[55] , wherein the disinfectant is at least one selected from the group consisting of sodium hypochlorite, hypochlorous acid, sodium chlorite, chlorous acid, peracetic acid, hydrogen peroxide, ethanol, and an organic acid.

[57] The manufacturing method of any of

[53] to

[56] , wherein broccoli or cauliflower is brought into contact with water, and the water is a nutrient solution.

[0127]

[58] The manufacturing method of any one of [1] to

[57] , wherein the curing is carried out while irradiating light.

[59] The manufacturing method of any one of [1] to

[57] , wherein the curing is carried out in a dark room.

[60] The manufacturing method of any one of [1] to

[59] , further comprising a blanching step.

[61] The manufacturing method of

[60] , wherein the blanching is started within 4 hours after the end of the curing.

[62] Frozen broccoli or frozen cauliflower obtained by the manufacturing method of any one of [1] to

[61] .

[0128]

[63] A method for improving the texture of frozen broccoli or cauliflower, comprising a step of curing harvested broccoli or cauliflower before freezing.

[64] The method of

[63] , wherein the curing temperature and time combination is one of the following [A] to [C]: [A] 10°C or higher but lower than 15°C, 75 hours or higher but lower than 200 hours; [B] 15°C or higher but lower than 25°C, 5 hours or higher but lower than 150 hours; [C] 25°C or higher but lower than 40°C, 2 hours or higher but lower than 100 hours.

[0129]

[65] The manufacturing method of

[64] , wherein the combination of temperature and time in the curing is the above [A], and the curing time is 80 hours or more.

[66] The manufacturing method of

[64] , wherein the combination of temperature and time in the curing is the above [A], and the curing time is 90 hours or more.

[67] The manufacturing method of

[64] , wherein the combination of temperature and time in the curing is the above [A], and the curing time is 100 hours or more.

[0130]

[68] The manufacturing method of any of

[64] to

[67] , wherein the combination of temperature and time in the curing is [A] above, and the curing time is 180 hours or less.

[69] The manufacturing method of any of

[64] to

[67] , wherein the combination of temperature and time in the curing is [A] above, and the curing time is 160 hours or less.

[70] The manufacturing method of any of

[64] to

[67] , wherein the combination of temperature and time in the curing is [A] above, and the curing time is 140 hours or less.

[0131]

[71] The manufacturing method of

[64] , wherein the combination of temperature and time in the curing is [B] above, and the curing time is 10 hours or more.

[72] The manufacturing method of

[64] , wherein the combination of temperature and time in the curing is [B] above, and the curing time is 15 hours or more.

[73] The manufacturing method of

[64] , wherein the combination of temperature and time in the curing is [B] above, and the curing time is 19 hours or more.

[74] The manufacturing method of

[64] , wherein the combination of temperature and time in the curing is [B] above, and the curing time is 21 hours or more.

[0132]

[75] The manufacturing method of any one of

[64] and

[71] to

[74] , wherein the combination of temperature and time in the curing is [B] above, and the curing time is 130 hours or less.

[76] The manufacturing method of any one of

[64] and

[71] to

[74] , wherein the combination of temperature and time in the curing is [B] above, and the curing time is 100 hours or less.

[77] The manufacturing method of any one of

[64] and

[71] to

[74] , wherein the combination of temperature and time in the curing is [B] above, and the curing time is 90 hours or less.

[78] The manufacturing method of any one of

[64] and

[71] to

[74] , wherein the combination of temperature and time in the curing is [B] above, and the curing time is 80 hours or less.

[79] The manufacturing method of any one of

[64] and

[71] to

[74] , wherein the combination of temperature and time in the curing is [B] above, and the curing time is 70 hours or less.

[80] The manufacturing method of any one of

[64] and

[71] to

[74] , wherein the combination of temperature and time in the curing is [B] above and the curing time is 50 hours or less.

[81] The manufacturing method of any one of

[64] and

[71] to

[74] , wherein the combination of temperature and time in the curing is [B] above and the curing time is 30 hours or less.

[0133]

[82] The manufacturing method of any one of

[64] and

[71] to

[81] , wherein the combination of temperature and time in the curing is [B] above, and the temperature in the curing is 16°C or higher.

[83] The manufacturing method of any one of

[64] and

[71] to

[81] , wherein the combination of temperature and time in the curing is [B] above, and the temperature in the curing is 17°C or higher.

[84] The manufacturing method of any one of

[64] and

[71] to

[81] , wherein the combination of temperature and time in the curing is [B] above, and the temperature in the curing is 18°C ​​or higher.

[0134]

[85] The manufacturing method of any one of

[64] and

[71] to

[84] , wherein the combination of temperature and time in the curing is [B] above, and the temperature in the curing is 24°C or less.

[86] The manufacturing method of any one of

[64] and

[71] to

[84] , wherein the combination of temperature and time in the curing is [B] above, and the temperature in the curing is 23°C or less.

[87] The manufacturing method of any one of

[64] and

[71] to

[84] , wherein the combination of temperature and time in the curing is [B] above, and the temperature in the curing is 22°C or less.

[0135]

[88] The manufacturing method of

[64] , wherein the combination of temperature and time in the curing is [C] above, and the curing time is 4 hours or more.

[89] The manufacturing method of

[64] , wherein the combination of temperature and time in the curing is [C] above, and the curing time is 5 hours or more.

[90] The manufacturing method of

[64] , wherein the combination of temperature and time in the curing is [C] above, and the curing time is 8 hours or more.

[91] The manufacturing method of

[64] , wherein the combination of temperature and time in the curing is [C] above, and the curing time is 10 hours or more.

[92] The manufacturing method of

[64] , wherein the combination of temperature and time in the curing is [C] above, and the curing time is 20 hours or more.

[0136]

[93] The manufacturing method of any one of

[64] and

[88] to

[92] , wherein the combination of temperature and time in the curing is [C] above, and the curing time is 90 hours or less.

[94] The manufacturing method of any one of

[64] and

[88] to

[92] , wherein the combination of temperature and time in the curing is [C] above, and the curing time is 70 hours or less.

[95] The manufacturing method of any one of

[64] and

[88] to

[92] , wherein the combination of temperature and time in the curing is [C] above, and the curing time is 50 hours or less.

[96] The manufacturing method of any one of

[64] and

[88] to

[92] , wherein the combination of temperature and time in the curing is [C] above, and the curing time is 40 hours or less.

[97] The manufacturing method of any one of

[64] and

[88] to

[92] , wherein the combination of temperature and time in the curing is [C] above, and the curing time is 30 hours or less.

[0137]

[98] The manufacturing method of any one of

[64] and

[88] to

[97] , wherein the combination of temperature and time in the curing is [C] above, and the curing temperature is 38°C or less.

[99] The manufacturing method of any one of

[64] and

[88] to

[97] , wherein the combination of temperature and time in the curing is [C] above, and the curing temperature is 36°C or less.

[100] The manufacturing method of any one of

[64] and

[88] to

[97] , wherein the combination of temperature and time in the curing is [C] above, and the curing temperature is 34°C or less.

[101] The manufacturing method of any one of

[64] and

[88] to

[97] , wherein the combination of temperature and time in the curing is [C] above, and the curing temperature is 32°C or less.

[0138]

[102] Any of the methods

[63] to

[101] , which is a method for improving the texture of frozen broccoli or frozen cauliflower using broccoli or cauliflower harvested on a harvesting day when the average temperature over the four days before harvesting, including the harvesting day, is 15° C. or less.

[103] Any of the methods

[63] to

[101] , which is a method for improving the texture of frozen broccoli or frozen cauliflower using broccoli or cauliflower harvested on a harvesting day when the average temperature over the four days before harvesting, including the harvesting day, is 12° C. or less.

[104] Any of the methods

[63] to

[101] , which is a method for improving the texture of frozen broccoli or frozen cauliflower using broccoli or cauliflower harvested on a harvesting day when the average temperature over the four days before harvesting, including the harvesting day, is 10° C. or less.

[105] Any of the methods

[63] to

[104] , which is a method for improving the texture of frozen broccoli or frozen cauliflower using broccoli or cauliflower harvested on a harvesting day when the average minimum temperature during the four days before harvesting, including the harvesting day, is 8° C. or less.

[106] Any of the methods

[63] to

[104] , which is a method for improving the texture of frozen broccoli or frozen cauliflower using broccoli or cauliflower harvested on a harvesting day when the average minimum temperature during the four days before harvesting, including the harvesting day, is 6° C. or less.

[107] Any of the methods

[63] to

[104] , which is a method for improving the texture of frozen broccoli or frozen cauliflower using broccoli or cauliflower harvested on a harvesting day when the average minimum temperature during the four days before harvesting, including the harvesting day, is 7° C. or less.

[108] Any of the methods

[63] to

[107] , which is a method for improving the texture of frozen broccoli or frozen cauliflower using broccoli or cauliflower harvested in Japan in October, November, December, January, February, March, April, or May.

[0139]

[109] Any of the methods

[63] to

[108] , wherein the curing is carried out under atmospheric conditions.

[110] Any of the methods

[63] to

[108] , wherein the curing is carried out under humidified conditions.

[111] The method of

[110] , wherein the humidified conditions are either (1) or (2) below: (1) contacting broccoli or cauliflower with water; or (2) placing the broccoli or cauliflower in a humidified space.

[112] The method of

[110] or

[111] , wherein the broccoli or cauliflower is brought into contact with water, and a disinfectant is coexistent with the water.

[113] The method of

[112] , wherein the disinfectant is at least one selected from the group consisting of sodium hypochlorite, hypochlorous acid, sodium chlorite, chlorous acid, peracetic acid, hydrogen peroxide, ethanol, and an organic acid.

[114] The method according to any one of

[110] to

[113] , wherein the broccoli or cauliflower is contacted with water, and the water is a nutrient solution.

[0140]

[115] Any of the methods

[63] to

[114] , wherein the curing is carried out under light irradiation.

[116] Any of the methods

[63] to

[114] , wherein the curing is carried out in a dark room.

[117] Any of the methods

[63] to

[116] , further comprising a step of blanching.

[118] The method of

[117] , wherein the blanching is started within 4 hours after the end of the curing.

[119] Frozen broccoli or frozen cauliflower obtained by any of the methods

[63] to

[118] .

[0141]

[120] Frozen broccoli having a total pectin content of 11.0% by mass or more.

[121] Frozen broccoli having a total pectin content of 11.4% by mass or more.

[122] Frozen broccoli having a total pectin content of 11.8% by mass or more.

[123] Frozen broccoli having a total pectin content of 12.2% by mass or more.

[124] Frozen broccoli having a total pectin content of 12.6% by mass or more.

[125] Frozen broccoli having a total pectin content of 13.0% by mass or more.

[126] Frozen broccoli having a total pectin content of 13.4% by mass or more.

[127] Frozen broccoli having a total pectin content of 13.8% by mass or more.

[0142]

[128] The frozen broccoli of any of

[120] to

[127] , wherein the total pectin content of the starting broccoli is less than 11.0% by mass.

[129] The frozen broccoli of any of

[120] to

[127] , wherein the total pectin content of the starting broccoli is less than 10.6% by mass.

[130] The frozen broccoli of any of

[120] to

[127] , wherein the total pectin content of the starting broccoli is less than 10.4% by mass.

[0143]

[131] Frozen broccoli according to any one of

[120] to

[130] , wherein the raw material broccoli is broccoli harvested on a harvest day when the average temperature on the four days before harvest, including the harvest day, is 15°C or less.

[132] Frozen broccoli according to any one of

[120] to

[130] , wherein the raw material broccoli is broccoli harvested on a harvest day when the average temperature on the four days before harvest, including the harvest day, is 12°C or less.

[133] Frozen broccoli according to any one of

[120] to

[130] , wherein the raw material broccoli is broccoli harvested on a harvest day when the average temperature on the four days before harvest, including the harvest day, is 10°C or less.

[0144]

[134] Frozen broccoli according to any one of

[120] to

[133] , wherein the starting broccoli is harvested on a harvest day when the average minimum temperature in the four days before harvest, including the harvest day, is 8°C or less.

[135] Frozen broccoli according to any one of

[120] to

[133] , wherein the starting broccoli is harvested on a harvest day when the average minimum temperature in the four days before harvest, including the harvest day, is 6°C or less.

[136] Frozen broccoli according to any one of

[120] to

[133] , wherein the starting broccoli is harvested on a harvest day when the average minimum temperature in the four days before harvest, including the harvest day, is 5°C or less.

[137] Frozen broccoli according to any one of

[120] to

[133] , wherein the starting broccoli is harvested in Japan in October, November, December, January, February, March, April, or May.

Claims

1. A method for producing frozen broccoli or cauliflower, comprising a step of curing harvested broccoli or cauliflower before freezing.

2. The method according to claim 1, wherein the curing is carried out so that the rate of change in maximum load of the frozen broccoli or frozen cauliflower is 110% or more.

3. The manufacturing method according to claim 1 or 2, wherein the combination of temperature and time in the curing is any one of the following (A) to (C): (A) 10°C or higher and lower than 15°C, 75 hours or higher and 200 hours or lower (B) 15°C or higher and lower than 25°C, 5 hours or higher and 150 hours or lower (C) 25°C or higher and lower than 40°C, 2 hours or higher and 100 hours or lower 4. The method according to claim 1 or 2, wherein broccoli or cauliflower is used that has been harvested on a harvest date when the average of the average temperature for the four days before harvest, including the harvest date, is 20° C. or lower.

5. The method according to claim 1 or 2, wherein broccoli or cauliflower is harvested on a harvest date when the average minimum temperature on the four days before harvest, including the harvest date, is 18° C. or lower.

6. The method according to claim 1 or 2, wherein broccoli or cauliflower harvested in October, November, December, January, February, March, April or May in Japan is used.

7. The manufacturing method according to claim 1 or 2, wherein the curing is carried out in an air atmosphere.

8. The method according to claim 1 or 2, wherein the curing is carried out under humid conditions.

9. The method according to claim 8, wherein the humidification conditions are either (1) or (2) below: (1) contacting broccoli or cauliflower with water; and (2) placing broccoli or cauliflower in a humidified space.

10. The method according to claim 8, wherein the broccoli or cauliflower is contacted with water, and the water also contains a bactericide.

11. The method of claim 10, wherein the disinfectant is at least one selected from the group consisting of sodium hypochlorite, hypochlorous acid, sodium chlorite, chlorous acid, peracetic acid, hydrogen peroxide, ethanol, and an organic acid.

12. The method of claim 8, wherein the broccoli or cauliflower is contacted with water, and the water is a nutrient solution.

13. The manufacturing method according to claim 1 or 2, wherein the curing is carried out while irradiating with light.

14. The method according to claim 1 or 2, wherein the curing is carried out in a dark room.

15. The method according to claim 1 or 2, further comprising a step of blanching.

16. The method of claim 15, wherein the blanching is initiated within 4 hours after the curing is completed.

17. Frozen broccoli or frozen cauliflower obtained by the method according to claim 1 or 2.

18. A method for improving the texture of frozen broccoli or cauliflower, comprising a step of curing harvested broccoli or cauliflower before freezing.

19. The method according to claim 18, wherein the combination of temperature and time in the curing is any one of the following (A) to (C): (A) 10°C or higher and lower than 15°C, 75 hours or higher and 200 hours or lower (B) 15°C or higher and lower than 25°C, 5 hours or higher and 150 hours or lower (C) 25°C or higher and lower than 40°C, 2 hours or higher and 100 hours or lower 20. The method according to claim 18 or 19, which is a method for improving the texture of frozen broccoli or frozen cauliflower, using broccoli or cauliflower harvested on a harvest date when the average of the average temperature over the four days prior to harvest, including the harvest date, is 20°C or lower.

21. The method according to claim 18 or 19, which is a method for improving the texture of frozen broccoli or frozen cauliflower, using broccoli or cauliflower harvested on a harvest date when the average minimum temperature over the four days prior to harvest, including the harvest date, is 18°C ​​or lower.

22. The method according to claim 18 or 19, which is a method for improving the texture of frozen broccoli or frozen cauliflower using broccoli or cauliflower harvested in Japan in October, November, December, January, February, March, April or May.

23. The method according to claim 18 or 19, wherein the curing is carried out in an air atmosphere.

24. The method of claim 18 or 19, wherein the curing is carried out under moist conditions.

25. The method according to claim 24, wherein the humidified condition is either (1) or (2) below: (1) contacting the broccoli or cauliflower with water; or (2) placing the broccoli or cauliflower in a humidified space.

26. The method of claim 24, wherein the broccoli or cauliflower is contacted with water and the water is also in the presence of a disinfectant.

27. The method of claim 26, wherein the disinfectant is at least one selected from the group consisting of sodium hypochlorite, hypochlorous acid, sodium chlorite, chlorous acid, peracetic acid, hydrogen peroxide, ethanol, and an organic acid.

28. The method of claim 24, wherein the broccoli or cauliflower is contacted with water, and the water is a nutrient solution.

29. The method according to claim 18 or 19, wherein the curing is carried out under irradiation with light.

30. The method of claim 18 or 19, wherein the curing is carried out in a dark room.

31. The method of claim 18 or 19, further comprising the step of blanching.

32. The method of claim 31, wherein the blanching is initiated within 4 hours after the curing is completed.

33. Frozen broccoli having a total pectin content of 11.0% by mass or more on a dry basis.

34. The frozen broccoli according to claim 33, wherein the total pectin content of the starting broccoli is less than 11.0% by mass on a dry basis.

35. The frozen broccoli according to claim 33, wherein the starting broccoli is broccoli harvested on a harvest date when the average of the average temperature for the four days before harvest, including the harvest date, is 20° C. or lower.

36. The frozen broccoli according to claim 33, wherein the starting broccoli is broccoli harvested on a harvest date when the average minimum temperature on the four days prior to harvest, including the harvest date, is 18° C. or lower.

37. The frozen broccoli according to claim 33, wherein the starting broccoli is harvested in October, November, December, January, February, March, April or May in Japan.

Images