Method for producing steamed rice and steamed rice production device

Abstract

This method for producing steamed rice comprises: a first rice steaming step of steaming a rice ingredient containing rice with steam while supplying a supplement liquid containing water to the rice ingredient in a first zone in a steamed rice production device; and a second rice steaming step of steaming the rice ingredient with steam without supplying water to the rice ingredient in a second zone in the steamed rice production device after the first rice steaming step.

Description

Steamed rice production method and steamed rice production device

[0001] The present disclosure relates to a steamed rice producing method and a steamed rice producing apparatus.

[0002] Unlike the rice cooking method using a pot, the rice steaming method is known, in which the rice is cooked by steaming it with high-temperature steam without being immersed in water.

[0003] For example, Patent Document 1 discloses a method for producing cooked rice that aims to cook rice without soaking the rice in water.

[0004] JP 2014-226062 A

[0005] The quality of cooked rice is evaluated from multiple perspectives, such as whether cooked rice with a taste and texture that suits the consumer's preferences can be provided, whether variation in the quality of cooked rice can be sufficiently reduced, and the amount of cooked rice per unit time (i.e., productivity).

[0006] The steaming method described above is suitable for continuously and stably cooking large amounts of rice, but general steaming methods do not always produce high-quality cooked rice consistently.

[0007] The present disclosure provides techniques related to steamed rice that are advantageous for providing cooked rice of excellent quality.

[0008] One aspect of the present disclosure relates to a steamed rice production method including: a first rice steaming step in which a rice ingredient containing rice is steamed with steam in a first zone of a steamed rice production apparatus while a water-containing replenishment liquid is supplied to the rice ingredient; and a second rice steaming step in which, after the first rice steaming step, the rice ingredient is steamed with steam in a second zone of the steamed rice production apparatus without supplying water to the rice ingredient.

[0009] Another aspect of the present disclosure relates to a steamed rice producing apparatus including a conveying unit that conveys rice food material containing rice through a steamed rice zone including a first zone and a second zone located downstream of the first zone, a steam supplying unit that supplies steam to the first zone and the second zone, and a water supplying unit that supplies a replenisher liquid containing water to the rice food material conveyed by the conveying unit in the first zone, wherein the rice food material conveyed by the conveying unit in the second zone is steamed with steam but is not supplied with water.

[0010] The present disclosure is advantageous in providing cooked rice of excellent quality.

[0011] FIG. 1 is a diagram showing an example of a steamed rice producing apparatus according to the first embodiment.

[0012] Generally, to produce frozen processed cooked rice food, a rice cooking step, a step of mixing seasonings and ingredients with cooked rice, other processing steps, a freezing step, and a packaging step may be carried out in this order.

[0013] The rice cooking process here can be carried out in a variety of ways, for example, using a rice cooker or steaming the rice with steam. In particular, the steamed rice cooking method, in which rice is cooked by steaming it while being transported, can continuously produce a large amount of cooked rice (steamed rice), and is advantageous from the viewpoint of smoothly and continuously carrying out various processes carried out downstream of the rice cooking process.

[0014] Hereinafter, an embodiment of a steamed rice producing method and a steamed rice producing apparatus for producing cooked rice by steaming rice will be described.

[0015] The devices and methods of each of the following embodiments are suitably applicable to methods and devices for producing frozen processed rice foods (particularly rice cooking methods and rice cooking devices), but can also be appropriately applied to simple rice cooking methods and rice cooking devices or methods and devices used for any other purpose.

[0016] In the following explanation, unless otherwise specified, the terms "upstream" and "downstream" refer to the transport of rice (rice food material), and terms relating to the up-down direction, such as "above" and "below," refer to the height direction (i.e., the direction along the direction of gravity).

[0017] [First embodiment] Fig. 1 is a diagram showing an example of a steamed rice producing apparatus 10 used in a steamed rice producing method according to the first embodiment. Fig. 1 shows the inside of a chamber unit 20.

[0018] In the steamed rice producing apparatus 10 shown in FIG. 1, the steamed rice zone Z0 in the chamber unit 20, where rice is cooked by steaming it with steam, is divided into a first zone Z1 and a second zone Z2.

[0019] The first zone Z1 is a zone where a first rice steaming step is carried out, in which rice is steamed with steam while water is added. On the other hand, the second zone Z2 is a zone where a second rice steaming step is carried out, in which rice is steamed with steam without the addition of water. Therefore, the steamed rice production method of this embodiment includes a first rice steaming step in which rice is steamed with steam while supplying water (supplement liquid L, described below) to the rice in the first zone Z1, and a second rice steaming step in which rice is steamed with steam in the second zone Z2 after the first rice steaming step, without supplying water to the rice.

[0020] In this embodiment, the first zone Z1 and the second zone Z2 are positioned so as to be offset from each other in the horizontal direction. The rice to be cooked (specifically, the rice ingredient R) is transported continuously from the first zone Z1 to the second zone Z2 by a common transport unit 11.

[0021] The steamed rice producing apparatus 10 shown in FIG. 1 includes a rice supply unit 31, a conveying unit 11, a steam supply unit 12, a stirring device 13, and a water supply unit 14.

[0022] The rice supply unit 31 is at least partially provided outside the chamber unit 20. On the other hand, the conveying unit 11, the steam supply unit 12, the stirring device 13, and the water supply unit 14 are each at least partially provided inside the chamber unit 20.

[0023] Within the chamber unit 20 (i.e., the first zone Z1 and the second zone Z2), the ambient temperature around the rice food material R transported by the transport unit 11 is a temperature suitable for steaming rice, for example, 90°C or higher (more preferably 95°C or higher).

[0024] The atmosphere inside the chamber unit 20 basically has a temperature higher than room temperature due to the steam from the steam supply unit 12 and the replenishment liquid L from the water supply unit 14. Therefore, it is also possible to adjust the atmospheric temperature inside the chamber unit 20 to a desired temperature suitable for steamed rice cooking using only the steam from the steam supply unit 12 and the replenishment liquid L from the water supply unit 14.

[0025] However, a heater (not shown) may be installed in the chamber unit 20 to adjust the atmosphere around the rice food material R transported by the transport unit 11 to a desired temperature suitable for steaming rice.

[0026] The rice supply unit 31 is attached to the chamber unit 20 and has a hopper for storing rice food material R outside the chamber unit 20, and supplies the rice food material R to the conveying unit 11 inside the chamber unit 20. Although the specific configuration of the rice supply unit 31 is not limited, the rice supply unit 31 supplies a desired amount of rice food material R to the conveying unit 11 in a timely manner as needed under the control of a control unit (not shown).

[0027] The rice contained in the rice food material R supplied from the rice supply unit 31 to the conveying unit 11 is uncooked rice.

[0028] The rice food ingredient R typically contains only rice, but may contain other ingredients in addition to rice. There is no limitation on the ingredients other than rice that may be contained in the rice food ingredient R. For example, any ingredients and any seasonings that can be mixed with rice may be contained as other ingredients in the rice food ingredient R.

[0029] The rice contained in the rice food ingredient R supplied from the rice supply unit 31 to the conveying unit 11 may be rice that has absorbed water by being soaked in water beforehand. As an example, rice food ingredient R containing rice that has been soaked in water beforehand for 1 hour or more and less than 30 hours in an environment at room temperature (1 to 30°C (e.g., 25°C)) or a temperature lower than room temperature may be stored in the rice supply unit 31. However, the rice supply unit 31 may also store rice that has not been soaked in water beforehand and supply it to the conveying unit 11.

[0030] The conveying unit 11 conveys the rice food material R throughout the steamed rice zone Z0, which includes the first zone Z1 and the second zone Z2 located downstream of the first zone Z1.

[0031] 1 has an endless conveyor belt supported by two or more rotating rollers. The most downstream rotating roller is provided outside the chamber unit 20, and the conveyor belt extends inside and outside the chamber unit 20. At least one of the two or more rotating rollers is rotated by power from a power source (not shown) such as a motor, thereby moving the conveyor unit 11 continuously or intermittently.

[0032] The portion of the conveying belt whose exposed surface faces upward (hereinafter also referred to as the "upper belt portion") carries rice food material R supplied from the rice supply unit 31, and moves through the first zone Z1 and the second zone Z2 with the rice food material R loaded thereon.

[0033] The rice food material R on the conveyor belt is steamed and cooked while passing through the first zone Z1 and the second zone Z2, and is conveyed in the form of cooked rice to the outside of the chamber unit 20. Outside the chamber unit 20, the cooked rice food material R is sent to another downstream device (for example, a cooked rice processing device or a cooked rice storage section).

[0034] The conveyor belt has a large number of belt through-holes (not shown) formed throughout, and the conveyor belt can be configured by, for example, a net conveyor. Although the diameter of each belt through-hole is not limited, each belt through-hole has a diameter large enough to allow the steam from the steam supply unit 12 and the replenishment liquid L from the water supply unit 14 to pass through (typically a diameter of several millimeters or less (e.g., 1 to 2 millimeters or less)).

[0035] The steam supply unit 12 supplies steam to the first zone Z1 and the second zone Z2. The rice food material R transported by the transport unit 11 is steamed with the steam supplied from the steam supply unit 12, thereby being cooked.

[0036] The steam supplied from the steam supply unit 12 is typically water vapor, but may be steam containing components other than water. The steam supplied from the steam supply unit 12 is not limited to saturated steam, and may include superheated steam.

[0037] The steam supply unit 12 shown in Figure 1 has a steam generating section 12a that generates steam outside the chamber unit 20, and a steam ejection line 12b that ejects the steam sent from the steam generating section 12a inside the chamber unit 20.

[0038] The steam ejection line 12b is provided below the upper belt portion of the conveyor belt of the conveyor unit 11, and has a large number of steam ejection holes (not shown) for ejecting steam.

[0039] The steam ejection line 12b extends across the first zone Z1 and the second zone Z2 between the portion of the conveying belt whose exposed surface faces downward (hereinafter also referred to as the "lower belt portion") and the upper belt portion.

[0040] The numerous steam ejection holes of the steam ejection line 12b are evenly distributed throughout the first zone Z1 and the second zone Z2. The steam ejected from each steam ejection hole of the steam ejection line 12b passes through the belt through-holes of the conveyor belt of the conveyor unit 11 and moves above the conveyor belt. As a result, the steam surrounds the rice food material R on the conveyor belt (upper belt portion) and is used to steam the rice food material R.

[0041] At least one stirring device 13 for stirring the rice food material R transported by the transport unit 11 is provided in at least one of the first zone Z1 and the second zone Z2.

[0042] 1, a plurality of stirring devices 13 are provided across the first zone Z1 and the second zone Z2 above the conveyor belt (particularly the upper belt portion) of the conveying unit 11. Each stirring device 13 has a rotatable main body and a plurality of blades extending outward from the periphery of the main body. As the main body rotates, the blades rotate and come into contact with the rice food ingredient R on the conveyor belt, promoting stirring of the rice food ingredient R.

[0043] The stirring device 13 is not limited to the example shown in Fig. 1 and may have any configuration. For example, instead of directly contacting and stirring the rice food material R on the conveyor belt, the stirring device 13 may blow air onto the rice food material R or vibrate the rice food material R via the conveyor belt.

[0044] In the first zone Z1, the water supply unit 14 supplies replenishment liquid L containing water by sprinkling onto the rice food material R transported by the transport unit 11. That is, the water supply unit 14 has multiple liquid discharge ports (not shown) and discharges replenishment liquid L from these liquid discharge ports in a shower-like manner toward the rice food material R on the transport belt. As a result, the replenishment liquid L from the water supply unit 14 is uniformly applied to the entire rice food material R moving through the first zone Z1 together with the transport belt. The discharge of replenishment liquid L from the multiple liquid discharge ports may be performed multiple times, continuously, or intermittently.

[0045] As an example, while the rice food ingredient R passes through the first zone Z1, the water supply unit 14 may add replenishment liquid L in the range of 0.5 to 1.7 L per 1 kg of raw rice contained in the rice food ingredient R. The water supply unit 14 may preferably add replenishment liquid L in the range of 0.55 to 1.5 L, and more preferably in the range of 0.6 to 1.3 L, per 1 kg of such raw rice. The amount of replenishment liquid L added from the water supply unit 14 can be adjusted as appropriate depending on the rice variety, the desired texture and moisture content of the rice, etc.

[0046] 1 includes a plurality of water supply devices 14a, which are attached to the chamber unit 20 at a position higher than the conveyor belt of the conveyor unit 11. Each water supply device 14a has one or more liquid outlets that discharge replenishment liquid L inside the chamber unit 20.

[0047] There are no limitations on the specific arrangement of the multiple water supply devices 14a and the specific manner in which each water supply device 14a discharges the replenishment liquid L. For example, each water supply device 14a may discharge the replenishment liquid L in only one direction, or may discharge the replenishment liquid L in multiple directions.

[0048] However, at least two of the multiple water supply devices 14a are provided in the first zone Z1 at intervals from the upstream side to the downstream side of the conveyance of the rice food material R. That is, in the first zone Z1, the water supply devices 14a are provided at each of multiple locations (for example, about 6 to 10 locations) that are spaced apart from each other in the conveyance direction Dc of the rice food material R.

[0049] The plurality of water supply devices 14a installed in multiple locations in this manner may supply the replenishment liquid L to the rice food ingredient R continuously in the conveying direction Dc of the rice food ingredient R in the first zone Z1. Alternatively, the plurality of water supply devices 14a may supply the replenishment liquid L to the rice food ingredient R intermittently in the conveying direction Dc of the rice food ingredient R in the first zone Z1. That is, in the first zone Z1, there may be regions where the rice food ingredient R on the conveyor belt directly receives the replenishment liquid L from the water supply devices 14a and regions where the rice food ingredient R does not directly receive the replenishment liquid L.

[0050] In addition, two or more water supply devices 14a may be provided at intervals in the width direction of the conveyor belt (the direction perpendicular to the plane of the paper in FIG. 1 ), or only a single water supply device 14a may be provided. The "width direction of the conveyor belt" here refers to a horizontal direction perpendicular to the conveying direction Dc of the rice food ingredient R by the conveyor belt (i.e., the running direction of the upper belt portion). The replenishment liquid L may be uniformly applied to the entire rice food ingredient R by simultaneously supplying the replenishment liquid L from one or more water supply devices 14a across the entire width direction of the rice food ingredient R on the conveyor belt.

[0051] 1, the temperature of the replenishment liquid L supplied to the rice food ingredient R by the water supply device 14a, of the multiple water supply devices 14a, that is located closest to the second zone Z2 is lower than the temperatures of the replenishment liquid L supplied to the rice food ingredient R by the other water supply devices 14a. By relatively lowering the temperature of the replenishment liquid L supplied to the location closer to the second zone Z2 in this way, the surface viscosity of the rice food ingredient R (particularly cooked rice) after cooking can be effectively suppressed.

[0052] As an example, the temperature of the replenishment liquid L applied to the rice food ingredient R from the water supply device 14a other than the water supply device 14a located closest to the second zone Z2 may be adjusted to 60°C or higher and 90°C or lower (e.g., 60°C or higher and 70°C or lower). In this case, the inventors have confirmed that by setting the temperature of the replenishment liquid L applied to the rice food ingredient R from the water supply device 14a located closest to the second zone Z2 to 40°C or lower (e.g., 20°C to 30°C), the surface viscosity of the rice food ingredient R after cooking can be significantly reduced.

[0053] 1 includes a plurality of storage sections 32 (i.e., a first storage section 32a and a second storage section 32b) that store the supply liquid L. At least one of the plurality of water supply devices 14a discharges the supply liquid L sent from the first storage section 32a, and the other water supply devices 14a discharge the supply liquid L sent from a storage section other than the first storage section 32a (the second storage section 32b).

[0054] 1, the first reservoir 32a and the second reservoir 32b store replenishment liquid L at different temperatures. That is, the first reservoir 32a stores replenishment liquid L at a relatively low temperature, and the second reservoir 32b stores replenishment liquid L at a relatively high temperature.

[0055] Of the multiple water supply devices 14a, the water supply device 14a located closest to the second zone Z2 dispenses low-temperature make-up liquid L sent from the first storage section 32a. At least one of the other water supply devices 14a (all of the other water supply devices 14a in the example shown in FIG. 1) dispenses high-temperature make-up liquid L sent from the second storage section 32b.

[0056] According to the steamed rice producing apparatus 10 described above, the rice food material R transported by the transport unit 11 is steamed with steam in the first zone Z1 while receiving a supply of replenishment liquid L, and then steamed with steam in the second zone Z2 without receiving a supply of replenishment liquid L, thereby cooking the rice.

[0057] The time for which the rice food ingredient R is steamed with steam in the first zone Z1 (first rice steaming process time) and the time for which the rice food ingredient R is steamed with steam in the second zone Z2 (second rice steaming process time) are adjusted according to the actual state of the rice food ingredient R.

[0058] The present inventors performed rice cooking multiple times while changing the first steaming step time and the second steaming step time using the steamed rice production apparatus 10, and evaluated the quality of the rice cooking technique for each cooking. As a result, they discovered that adjusting the first steaming step time and the second steaming step time as follows is advantageous for consistently providing high-quality cooked rice.

[0059] That is, the time for the second rice steaming process is preferably 3 / 10 or more of the total time of the first rice steaming process and the second rice steaming process. Also, the time for the second rice steaming process is preferably 1 / 2 or less of the total time of the first rice steaming process and the second rice steaming process.

[0060] The total time for the first rice steaming step and the second rice steaming step may vary depending on the rice content in the rice food ingredient R and other ingredients contained in the rice food ingredient R, but is, for example, about 15 to 25 minutes.

[0061] The inventors of the present invention performed various types of rice cooking (Examples 1 and 2) and evaluated the quality of the rice cooking from various perspectives.

[0062] Specifically, in Example 1, rice was cooked using the steamed rice production apparatus 10 described above, and the replenishment liquid L was supplied to the rice food ingredient R only in the first zone Z1 of the steamed rice zone Z0. In Example 2, in the steamed rice production apparatus 10 described above, a water supply unit 14 (plurality of water supply devices 14a) was also installed in the second zone Z2, and the replenishment liquid L was supplied to the rice food ingredient R in the entire steamed rice zone Z0 (both the first zone Z1 and the second zone Z2).

[0063] Other rice cooking conditions were made as similar as possible between Examples 1 and 2, and Examples 1 and 2 were carried out using rice food material R containing only rice.

[0064] The evaluation results of the cooked rice obtained in each of Examples 1 and 2 (i.e., the sensory evaluation results of the evaluators) are shown in Table 1 below.

[0065]

[0066] In Table 1 above, "Good" indicates a better result than "Average."

[0067] For example, the cooked rice obtained in Example 1 was superior to the cooked rice obtained in Example 2 in terms of "fluffiness."

[0068] Furthermore, with regard to the "graininess" and "lack of stickiness" of the cooked rice, the cooked rice obtained in Example 1 was comparable to and superior to the cooked rice obtained in Example 2.

[0069] As is clear from Table 1 above, the steamed rice production apparatus 10 and the steamed rice production method (Example 1) shown in FIG. 1 showed a good overall rice cooking evaluation and are advantageous for obtaining high-quality cooked rice.

[0070] As described above, according to this embodiment, a necessary and sufficient amount of water (supplement liquid L) is supplied to the first zone Z1 located on the upstream side of the rice steaming zone Z0, while steaming rice is performed without supplying water as a liquid to the second zone Z2 located on the downstream side of the rice steaming zone Z0.

[0071] This allows for the provision of high-quality cooked rice.

[0072] Furthermore, according to this embodiment, the first zone Z1 and the second zone Z2 are provided adjacent to each other in the horizontal direction, which simplifies the configuration of the steamed rice producing apparatus 10. For example, a common conveying unit 11 can be used between the first zone Z1 and the second zone Z2, and the rice food material R can be conveyed between the first zone Z1 and the second zone Z2 by the single conveying unit 11.

[0073] Second Embodiment In this embodiment, elements that are the same as or correspond to those in the first embodiment described above are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0074] In the first embodiment described above, the first zone Z1 and the second zone Z2 are positioned with a horizontal offset, but the first zone Z1 and the second zone Z2 may be positioned with a vertical offset.

[0075] Although not shown, the steamed rice producing apparatus 10 according to the second embodiment has a plurality of steamed rice units that are offset in the vertical direction. For example, three tiers of steamed rice units (a first steamed rice unit, a second steamed rice unit, and a third steamed rice unit) may be provided.

[0076] When three tiers of steaming rice units are provided, the first steaming rice unit, the second steaming rice unit, and the third steaming rice unit are arranged, for example, in this order from highest to lowest. That is, the third steaming rice unit is positioned lower than the first steaming rice unit, and the second steaming rice unit is positioned between the first steaming rice unit and the third steaming rice unit in the height direction.

[0077] The water supply unit 14 of this embodiment also includes a plurality of water supply devices 14a.

[0078] The first steaming rice unit may be provided with one or more water supply devices 14a, include the first zone Z1 but not the second zone Z2, and the entire first steaming rice unit may be provided as the first zone Z1.

[0079] The second rice steaming unit is provided with one or more water supply devices 14a and may include both a first zone Z1 and a second zone Z2. In this case, the upstream side of the second rice steaming unit is provided as a first zone Z1 where the replenishment liquid L from the water supply device 14a is applied to the rice food ingredient R transported by the transport unit 11. On the other hand, the downstream side of the second rice steaming unit is provided as a second zone Z2 where the replenishment liquid L is not applied to the rice food ingredient R.

[0080] The third steaming rice unit may not be provided with the water supply device 14a (i.e., the water supply unit 14), and may not include the first zone Z1 but may include the second zone Z2. That is, the entire third steaming rice unit may be provided as the second zone Z2.

[0081] The first steaming rice unit, the second steaming rice unit, and the third steaming rice unit basically have a common configuration except for the configuration related to the water supply unit 14 (water supply device 14a). That is, each of the first steaming rice unit to the third steaming rice unit has a conveying unit 11, a steam supply unit 12, and a stirring device 13 similar to those of the steamed rice producing apparatus 10 of the first embodiment described above.

[0082] However, the conveying direction of the rice food ingredient R in the first steaming rice unit and the conveying direction of the rice food ingredient R in the second steaming rice unit may be opposite to each other. Also, the conveying direction of the rice food ingredient R in the second steaming rice unit and the conveying direction of the rice food ingredient R in the third steaming rice unit may be opposite to each other.

[0083] Other configurations of the steamed rice producing apparatus 10 of this embodiment may be similar to those of the steamed rice producing apparatus 10 of the first embodiment described above.

[0084] According to the steamed rice producing apparatus 10 and steamed rice producing method of this embodiment, a portion of the conveying unit 11 of the second steaming rice unit can extend directly below the conveying unit 11 of the first steaming rice unit. Also, a portion of the conveying unit 11 of the third steaming rice unit can extend directly below the conveying unit 11 of the second steaming rice unit.

[0085] In this case, it is possible to ensure a sufficiently long steamed-rice zone Z0 (i.e., the first zone Z1 and the second zone Z2) while suppressing an increase in the horizontal installation space for the entire steamed-rice producing apparatus 10.

[0086] In the steamed rice producing apparatus 10 and steamed rice producing method of this embodiment, a plurality of water supply devices 14a may be provided so as to correspond to the entire second steamed rice unit.

[0087] That is, the second steaming rice unit may be provided with a plurality of water supply devices 14a so that the supply liquid L can be discharged toward the entire conveying unit 11 of the second steaming rice unit. In this case, the two or more water supply devices 14a in the second steaming rice unit are preferably provided spaced apart from each other from the upstream side to the downstream side in the conveying direction. Also, it is preferable that the discharge of the supply liquid L from each water supply device 14a provided in the second steaming rice unit can be switched on or off under the control of a control unit (not shown) or manually.

[0088] In this way, in the second rice steaming unit, by arranging a plurality of water supply devices 14a, which can switch between discharging and not discharging the supply liquid L, in the conveying direction, it is possible to adaptively adjust the ranges of the first zone Z1 and the second zone Z2 in the second rice steaming unit.

[0089] That is, the ranges of the first zone Z1 and the second zone Z2 in the second rice steaming unit can be adaptively changed by changing the water supplying device 14a that actually discharges the replenishment liquid L in the second rice steaming unit and the water supplying device 14a that does not actually discharge the replenishment liquid L. Therefore, the time during which the rice food ingredient R is steamed with steam in the first zone Z1 (first rice steaming process time) and the time during which the rice food ingredient R is steamed with steam in the second zone Z2 (second rice steaming process time) can be optimally adjusted according to the actual rice cooking conditions (for example, the state of the rice food ingredient R).

[0090] The optimal ratio of the first rice steaming process time and the second rice steaming process time can vary depending on various factors such as the components of the rice food material R, the season, the time of day, and the temperature and humidity of the surrounding environment. By adjusting the ratio of the first zone Z1 and the second zone Z2 of the second rice steaming unit in accordance with these factors, it is possible to optimize the ratio of the first rice steaming process time and the second rice steaming process time for the steamed rice producing apparatus 10 as a whole.

[0091] In this way, by varying the ratio of the first zone Z1 to the second zone Z2, a single steamed rice producing apparatus 10 can flexibly respond to various rice cooking conditions.

[0092] The transport speed of the rice food ingredient R by the transport unit 11 may or may not be the same between the first zone Z1 and the second zone Z2. For example, by changing the transport speed of the rice food ingredient R by the transport unit 11 in the first zone Z1, it is possible to flexibly adjust the first steaming step time in the entire rice steaming step (i.e., the steaming time in the first zone Z1). Furthermore, by changing the transport speed of the rice food ingredient R by the transport unit 11 in the second zone Z2, it is possible to flexibly adjust the second steaming step time in the entire rice steaming step (i.e., the steaming time in the second zone Z2).

[0093] [Modification] In the above-described embodiment, the plurality of reservoirs 32 (the first reservoir 32 a and the second reservoir 32 b) respectively store the replenishment liquid L at different temperatures, but the plurality of reservoirs 32 may respectively store a plurality of types of replenishment liquid L having different properties other than temperature. For example, a plurality of types of replenishment liquid L having different components may be stored in each reservoir 32.

[0094] Furthermore, in the above-described embodiment, one reservoir 32 (first reservoir 32a or second reservoir 32b) is assigned to each water supply unit 14, but two or more reservoirs 32 may be assigned to each water supply unit 14. For example, the replenishment liquid L from the first reservoir 32a and the replenishment liquid L from the second reservoir 32b may be blended midway, and the blended replenishment liquid L may be supplied to each water supply device 14a.

[0095] The present disclosure is not limited to the above-described embodiments and modifications. Various modifications may be made to each element of the above-described embodiments and modifications. Furthermore, the configurations of the above-described embodiments and modifications may be combined in whole or in part.

[0096] The technical category that embodies the above technical idea is not limited. For example, the above technical idea may be embodied by a computer program that causes a computer to execute one or more procedures (steps) included in the above method. Furthermore, the above technical idea may be embodied by a computer-readable non-transitory recording medium on which such a computer program is recorded.

[0097] [Additional Notes] As is clear from the above, the present disclosure includes the following aspects.

[0098] [Aspect 1] A method for producing steamed rice, comprising: a first rice-steaming step in a first zone of a steamed rice production apparatus, in which a water-containing replenishment liquid is supplied to a rice food ingredient containing rice, while the rice food ingredient is steamed with steam; and a second rice-steaming step in a second zone of the steamed rice production apparatus, after the first rice-steaming step, in which the rice food ingredient is steamed with steam without supplying water to the rice food ingredient.

[0099] [Aspect 2] The method for producing steamed rice according to Aspect 1, wherein the replenishment liquid is supplied to the rice food material by spraying water in the first zone.

[0100] [Aspect 3] The method for producing steamed rice according to Aspect 1 or 2, wherein the time during which the rice food ingredient is steamed with steam in the second zone is at least 3 / 10 of the total time during which the rice food ingredient is steamed with steam in the first zone and the second zone.

[0101] [Aspect 4] The method for producing steamed rice according to any one of Aspects 1 to 3, wherein the time during which the rice food ingredient is steamed with steam in the second zone is not more than half of the total time during which the rice food ingredient is steamed with steam in the first zone and the second zone.

[0102] [Aspect 5] The method for producing steamed rice according to any one of Aspects 1 to 4, wherein the rice food material is transported without interruption from the first zone to the second zone.

[0103] [Aspect 6] A steamed rice producing apparatus comprising: a conveying unit that conveys a rice food material containing rice through a steaming zone that includes a first zone and a second zone located downstream of the first zone; a steam supplying unit that supplies steam to the first zone and the second zone; and a water supplying unit that supplies a replenishment liquid containing water to the rice food material conveyed by the conveying unit in the first zone; wherein in the second zone, the rice food material conveyed by the conveying unit is steamed with the steam but is not supplied with water.

[0104] [Aspect 7] The steamed rice production apparatus according to Aspect 6, wherein the water supply unit includes a plurality of water supply devices, at least two of the plurality of water supply devices are provided in the first zone at intervals from the upstream side to the downstream side of the rice food material transport direction, and the temperature of the replenishment liquid supplied to the rice food material by the water supply device of the plurality of water supply devices that is provided closest to the second zone is lower than the temperatures of the replenishment liquid supplied to the rice food material by the other water supply devices.

[0105] [Aspect 8] The steamed rice producing apparatus according to Aspect 6 or 7, wherein the steamed rice producing apparatus includes a plurality of storage sections for storing the replenishment liquid, the plurality of storage sections including a first storage section, the water supply unit includes a plurality of water supply devices, and at least one of the plurality of water supply devices discharges the replenishment liquid sent from the first storage section, and the other water supply devices discharge the replenishment liquid sent from a storage section other than the first storage section.

[0106] REFERENCE SIGNS LIST 10 Steamed rice manufacturing apparatus 11 Conveying unit 12 Steam supply unit 12a Steam generating section 12b Steam ejection line 13 Stirring device 14 Water supply unit 14a Water supply device 20 Chamber unit 31 Rice supply unit 32 Storage section 32a First storage section 32b Second storage section Dc Conveying direction L Replenishment liquid R Rice food material Z0 Steamed rice zone Z1 First zone Z2 Second zone

Claims

1. In the first zone of the steamed rice production apparatus, a first steaming process is performed in which a replenishment liquid containing water is supplied to the rice ingredients containing rice, and the rice ingredients are steamed with steam. After the first steaming process, a second steaming process is performed in which the rice ingredients are steamed with steam in a second zone within the steaming apparatus without supplying water to the rice ingredients. A method for producing steamed rice, including the process itself.

2. The method for producing steamed rice according to claim 1, wherein the replenishment liquid is supplied to the rice ingredient by sprinkling water in the first zone.

3. The method for producing steamed rice according to claim 1 or 2, wherein the time for which the rice ingredient is steamed by steam in the second zone is 3 / 10 or more of the total time for which the rice ingredient is steamed by steam in the first zone and the second zone.

4. The method for producing steamed rice according to claim 1 or 2, wherein the time for which the rice ingredient is steamed by steam in the second zone is 1 / 2 or less of the total time for which the rice ingredient is steamed by steam in the first zone and the second zone.

5. The method for producing steamed rice according to claim 1 or 2, wherein the rice ingredients are transported from the first zone to the second zone without interruption.

6. A conveying unit for transporting rice ingredients, including rice, across a steamed rice zone that includes a first zone and a second zone located downstream of the first zone, A steam supply unit that supplies steam to the first zone and the second zone, The first zone includes a water supply unit that supplies a replenishment liquid containing water to the rice ingredients being transported by the transport unit, In the second zone, the rice ingredients transported by the transport unit are steamed by the steam, but no water is supplied. Steamed rice production equipment.

7. The water supply unit includes a plurality of water supply devices, At least two of the plurality of water supply devices are provided in the first zone spaced apart from each other from the upstream side to the downstream side of the transport of the rice ingredients. The steamed rice production apparatus according to claim 6, wherein the temperature of the replenishment liquid supplied to the rice ingredient by the water supply device located closest to the second zone among the plurality of water supply devices is lower than the temperature of the replenishment liquid supplied to the rice ingredient by the other water supply devices.

8. A plurality of storage sections for storing the replenishment liquid, comprising a plurality of storage sections including a first storage section, The water supply unit includes a plurality of water supply devices, The steamed rice production apparatus according to claim 6 or 7, wherein at least one of the plurality of water supply devices discharges the replenishment liquid sent from the first storage unit, and the other water supply devices discharge the replenishment liquid sent from storage units other than the first storage unit.