JP2019203049A - Rice oil production plant and rice oil production method, and rice oil obtained thereby - Google Patents

Abstract

To provide a plant and a production method for stably producing rice oil retaining a low acid value, and excellent in quality, flavor and nutrition characteristics, and to provide rice oil obtained thereby.SOLUTION: A rice oil production plant integrally comprises: a rice milling section which has a storage part 10, a rice milling part 20, a bran separation part 30 for making milled rice, and a milled rice storage part 40; and an oil squeezing section which has a bran supply line 50 directly connected to the bran separation part, and transporting rice bran by air current transportation, a fixed amount supply machine 70 charged with rice bran transported by the line and sending out a fixed amount of rice bran, a fixed amount rice bran supply line 80 having a pipe conduit for transporting a fixed amount of rice bran sent out by the supply machine, a heating/water adding machine 90 heating/adding water to supplied rice bran, and a compressing machine 110 compressing rice bran supplied by the heating/water adding machine. The rice milling section and the oil squeezing section are directly connected by the pipe conduit, and fresh rice bran is supplied so as to prevent an increase in an acid value of rice bran components, and obtain rice oil excellent in the aspects of quality, flavor and nutrition characteristics.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a rice oil production plant, a rice oil production method, and rice oil obtained thereby. More specifically, the present invention relates to a rice oil production plant and a rice oil production method capable of producing rice oil that retains a low acid value and is excellent in terms of quality, flavor, and nutritional characteristics, and rice oil obtained thereby. Is.

  Rice bran is a valuable food source that is rich in vitamins, minerals, fiber components, etc., and contains high-quality oils. More than 90% of the nutrients in brown rice are contained in rice bran. Since the annual production of rice bran in Japan is about 900,000 tons, the effective use of rice bran is an important issue in Japan, where most of the food depends on imports.

  Since rice bran contains 18 to 20% of fats and oils, it is a raw material for rice oil. Rice oil is the only vegetable oil that can supply almost all domestic raw materials. Rice oil is used for snacks, karinto, rice confectionery, mayonnaise and dressing because of its good flavor and stability, and it has become widely used for school lunches.

  A so-called solvent extraction method has been conventionally used as a method for obtaining rice oil from rice bran. In the solvent extraction method, first, the rice bran is subjected to dry extrusion or cooking, or wet extrusion or steam treatment to deactivate the lipase contained in the rice bran, and then the rice bran is treated with normal hexane. It is a method of extracting oil. The rice oil crude oil obtained by this method usually contains about 0.5% fine powder and 3-5% wax, and the crude oil is degummed, deacidified, dewaxed, decolored, and winter treated. Then it is deodorized.

  However, extraction of rice oil crude oil from rice bran using normal hexane causes more solvent loss than soybean oil and rapeseed oil, and a relatively large amount of solvent is released into the atmosphere. Has a negative effect. Conventionally, rice oil crude oil obtained from rice bran can be subjected to alkali refining with caustic soda, but if it is subjected to alkali refining, many nutrient components and physiologically active substances are lost.

  Therefore, a so-called pressing method in which rice bran is extracted by squeezing rice bran without using a solvent has attracted attention (see, for example, Patent Document 1). Since the pressing method does not use a solvent for rice bran, it not only has the characteristic that the flavor of the extracted rice oil is rich, but there is no risk of solvent remaining in the defatted rice bran. There are also significant advantages in using rice bran as a food.

  By the way, in general, when extracting rice oil crude oil from rice bran, the rice bran used as a raw material is stored as a by-product in the milled rice mill, for example, in a specified container such as a flexible container, and this is stored in a truck. It goes through a transportation process of transporting it to an essential oil factory by means of transportation.

  For this reason, until the rice bran used as a raw material is refined, the origin of the raw material including rice varieties and the quality of the raw material cannot be sufficiently controlled. In particular, the transport from the milled rice plant to the refinery process is considered to be a problem from the following viewpoints, especially under high temperature conditions such as summer.

  That is, not only rice but oil in plants is degraded by enzymes present in plants. Such decomposition immediately begins when the plant material is pulverized or milled, and in some cases, the decomposition of the oil proceeds to such an extent that extraction of edible oil from the plant material is not economically suitable. This is significant in rice bran with a relatively high oil content and a relatively high concentration of oil-degrading enzymes. By enzymatic decomposition, the oil is quickly decomposed into free fatty acids, which are sequentially oxidized to produce a bad odor. Since it comes out, it will become a thing with low utility value as an edible source. In general, when brown rice is polished, lipase in rice bran is immediately activated, and triglycerides in rice bran are hydrolyzed to produce free fatty acids, diglycerides and monoglycerides. As the amount of free fatty acids increases, the oxidation of free fatty acids produces a soapy odor in rice bran, making rice bran and rice oil unfit for consumption.

JP 2005-143364 A

  Therefore, the present invention provides a rice oil production plant and a rice oil production method capable of stably producing rice oil that retains a low acid value and is excellent in terms of quality, flavor, and nutritional characteristics, and rice oil obtained thereby. It is an issue to provide.

  The present invention that solves the above-mentioned problems is a rice oil production plant, which comprises a brown rice storage unit that stores brown rice, a rice milling unit that polishes brown rice, and a rice bran separation unit that removes rice bran from the polished rice to make white rice A rice bran having at least a white rice storage section for storing white rice, and a pipe that is connected directly to the rice bran separating section of the rice milling section and conveys the rice bran derived from the rice bran separating section by airflow conveyance. Quantitative rice bran supply having a supply line, a quantitative feeder supplying rice bran fed by the rice bran supply line and sending out a certain amount of rice bran, and a conduit for conveying a certain amount of rice bran delivered by the quantitative feeder Oil which comprises at least a line, a heating / hydrolyzing machine for heating / hydrolyzing the rice bran supplied from the quantitative rice bran supply line, and a pressing machine for pressing the rice bran supplied from the heating / hydrating machine Interval It is rice oil production plant, characterized in that to obtain.

  In the rice oil production plant, a rice bran storage tank is provided in the middle of the rice bran supply line, a system for air-feeding rice bran from the upstream side to the rice bran storage tank, and a rice bran stream from the rice bran storage tank to the downstream side. The aspect divided into the system | strain to convey may also be included.

  In the rice oil production plant, a mode in which a roasting machine for heating, drying and roasting rice bran is further provided between the heating / watering machine and the pressing machine.

  The present invention for solving the above-mentioned problems is also characterized in that the rice bran derived from the rice bran separating unit of the rice milling process is continuously conveyed to the oil extraction process by airflow conveyance through the pipe, and the supply amount of rice bran is quantified, This is a rice oil production method characterized by squeezing rice bran after heating and watering.

  In the said rice oil manufacturing method, the aspect which squeezes a rice bran within 4 to 5 hours from a milling process may be included as a preferable thing.

  This invention which solves the said subject is also the rice oil obtained by the said rice oil manufacturing method, Comprising: The acid value of the crude oil after pressing is 10 or less, The pressed rice oil characterized by the above-mentioned. Here, the “acid value” is a value as an index representing the size of the free fatty acid, and the lower the acid value, the smaller the free fatty acid.

  The compressed rice oil may include an embodiment in which the raw rice is a single variety.

  According to the rice oil production plant of the present invention, the rice bran produced by the milled rice can be sent directly from the milled rice section to the oil milled section by gas conveyance through the pipe line, so that the enzymatic decomposition of the fat contained in the rice bran occurs. It is difficult to maintain a low acid value and can stably produce rice oil excellent in quality, flavor and nutritional characteristics.

These are drawings which show typically the example of composition in one embodiment of the rice oil manufacturing plant concerning the present invention.

  Hereinafter, the present invention will be described in more detail based on embodiments.

  FIG. 1 is a drawing schematically showing a configuration example in an embodiment of a rice oil production plant. As shown in FIG. 1, in the rice oil manufacturing plant 1 which concerns on this embodiment, the brown rice storage part 10 which stores brown rice, the rice milling part 20 which mills brown rice, the rice bran separation part 30 which removes rice bran from milled rice, and makes white rice, and It has a milled rice section having at least a milled rice storage section 40 for storing milled rice, and a pipe line that is directly connected to the milled rice separation section 30 of the milled rice section and that conveys the rice bran derived from the rice bran separating section by airflow conveyance. A rice bran supply line 50, a rice bran fed by the rice bran feed line 50 is introduced and a fixed quantity feeder 70 for sending out a certain amount of rice bran, and a fixed quantity having a pipe line for carrying a certain amount of rice bran fed by the quantitative feeder. A rice bran supply line 80, a warming / hydrating machine 90 for heating and adding water to the rice bran supplied from the fixed quantity rice bran supply line, and a pressing machine 110 for pressing the rice bran supplied from the heating and adding machine At least a composed crush zone a is integrally formed.

  Further, in the embodiment shown in FIG. 1, in order to facilitate understanding of the present invention, the configuration is relatively simple. However, in the rice oil production plant according to the present invention, the configuration in the rice milling section is as follows. As described above, there is no particular limitation as long as it has a brown rice storage part, a rice milling part, a rice bran separation part, and a white rice storage part, and various forms can be included. For example, as seen in some known rice milling plants, a brown rice storage unit 10 for storing brown rice, a rice milling unit 20 for polishing brown rice, a rice bran separating unit 30 for removing rice bran from polished rice, and storing white rice A mode in which a plurality of white rice storage units 40 are provided, or a plurality of some of them and a branch line branched to connect from a plurality of parts to a single part and for switching The aspect which has a switching valve, the aspect which has the mixing part (not shown) etc. which mix the various white rice stored in the some white rice storage part 40, etc. may be sufficient. Furthermore, it may have a heat dryer, a rice cleaner for removing impurities, a particle size separator, etc. as required in a general rice milling plant.

  Further, the structure, form, etc. of the brown rice storage unit, the rice milling unit, the koji separation unit, and the white rice storage unit are not particularly limited. For example, as the milled portion, for example, a friction system such as a pressure circulation type or a friction stirring type, a grinding system using a metal sand roll, a ceramic roll, or the like, or a friction system and a grinding system Various forms such as a combination of and can be included. Also, the rice bran separating unit can be directly connected to the rice bran supply line having a pipe for conveying the rice bran derived from the rice bran separating unit by air flow conveyance, and the rice bran is substantially downstream without exposing the rice bran to the external environment. As long as it can be conveyed to the oil extraction section, it is not particularly limited. For example, various known modes such as a cyclone system, a centrifugal separation system, and an air classification system can be adopted.

  Furthermore, it is not particularly limited as a conveyance path that connects the respective parts of the rice milling section, and even if it is by any mechanical conveyance means such as a belt conveyor, it is a conveyance path by a pipe line that uses a natural head. Even if it exists, it may be the conveyance path by the pipe line which performs airflow conveyance, or what combined these. In addition, as a conveyance path after a rice milling part, in order to prevent the quality fall of rice or rice bran, it is preferable to make the inside of the pipe line substantially divided from the external environment into a conveyance path. Although not particularly limited, for example, in a certain embodiment, the conveyance path of the rice milling section includes the first transport pipe 11 that connects the brown rice storage unit 10 and the rice milling unit 20, the rice milling unit 20, and the rice bran separating unit. It has the 2nd transport pipe 21 which connects 30, and the 3rd transport pipe 31 which connects the rice bran separation part 30 and the white rice storage part 40, and is comprised by the pipe line partitioned from the external environment. It should be noted that the route of each transport pipe has a relatively large curvature, for example, a curvature of at least 500R or more, preferably about 1000R in order to prevent rice from colliding and being damaged at a steep angle. Can be configured.

  Further, although not particularly limited, each part and each conveyance path of the milled rice section are provided with an adjustment mechanism that adjusts the temperature and / or humidity of these parts to a predetermined temperature as necessary. be able to. The configuration of such an adjustment mechanism is not particularly limited, and a configuration known in this type of field can be appropriately changed and configured. For example, a measuring device for observing temperature and / or humidity is provided in each part or each conveyance path, and a blower is provided in each part or a part communicating with each conveyance path. And / or a dehumidifying (heating) device), and the temperature signal and humidity signal measured by the measuring device are transmitted to a control means having an automatic calculation device such as a microprocessor, and the control means receives the received temperature signal and humidity signal. And the stored predetermined temperature and / or humidity data are calculated, a value for controlling the air flow to be a predetermined temperature difference and / or humidity difference is calculated, and the blower (and the blower) is calculated. A command to control the value is transmitted to a device that cools (heats) and / or dehumidifies (heats) the blast on the front surface. Such temperature and / or humidity control may further include a feedback control system, as is well known.

  And in the rice oil manufacturing plant which concerns on this invention, the rice bran separation line 30 which has the pipe line which conveys the rice bran derived | led-out from the said rice bran separation part by airflow conveyance in the rice bran separation part 30 as mentioned above. Are directly connected, and the rice bran obtained in the milled rice section is supplied as it is to the oil extraction section installed on the downstream side without taking a predetermined elapsed time or more.

  Although it does not necessarily limit as airflow conveyance in the soot supply line 50, For example, it can carry out by the airflow introduce | transduced in the pipe line by the ventilation pump 51a distribute | arranged to the pipe line upstream. In addition, although it is common from a viewpoint of economical efficiency to use air, especially the air which desirably cleaned beforehand through the clean filter as carrier gas, carrier gas is not restricted to air. For example, in order to suppress oxidation of the rice bran to be conveyed, it is possible to use deoxidized air or an inert gas such as nitrogen. Furthermore, the carrier gas introduced into the pipe line for this conveyance can be used after adjusting the temperature and humidity as necessary in order to suppress oxidation of the rice bran to be conveyed. As a method for adjusting the temperature and humidity, for example, it is possible to use a mode similar to the method for adjusting the rice mill section described above.

  In addition, in the rice oil production plant 1 in the embodiment shown in FIG. 1, a rice bran storage tank 60 is provided in the middle of the rice bran supply line 50, and a system 50a (air flow of rice bran to the rice bran storage tank 60 from the upstream side) The gas flow by the blower pump 51a is used), and the system 50b (which uses the gas flow by the blower pump 51b) that conveys the rice bran from the rice bran storage tank 60 to the downstream side. In addition, since the rice bran storage tank 60 is provided in the middle of the rice bran supply line 50 in this way, the temporal variation in the amount of rice bran produced by the rice milling process in the rice milling section (for example, temporary stop of the rice milling process, etc.) Can be absorbed by temporarily storing the rice bran in the rice bran storage tank 60.

  The rice bran directly conveyed from the milled rice section by the rice bran supply line 50 is then introduced into the fixed quantity feeder 70 in the oil extraction section. The fixed amount feeder 70 is an apparatus for sending the rice bran that has been conveyed by gas as a certain amount of rice bran. As long as rice bran can be supplied to the downstream side in a constant amount with substantially no pulsation, it is not particularly limited to its form, etc., and is a load cell type that weighs and supplies, and a screw type that uses a helical screw to scoop Any known type such as a rotary type that drops a work into a mass partitioned by blades may be used.

  In addition, a certain amount of rice bran here is automatically adjusted automatically or via a prescribed program according to the situation so that the pressing process in the pressing machine 110 described later proceeds stably. can do. That is, in general, squeezing by a squeezer tends to be in a high load state at the initial stage of starting the squeezer, and the load is reduced to a steady state after a certain period of time. For this reason, the amount of rice bran sent to the press is monitored at a relatively small amount while monitoring the load on the press, and is supplied in a larger amount when the load on the press reaches a steady state. It is possible to adjust appropriately.

  A certain amount of rice bran fed by the metering feeder is then sent to the warming / watering machine 90 via the metered rice bran feeding line 80. The fixed quantity rice bran supply line is not particularly limited as a form thereof, and may be of an air flow conveying type similarly to the rice bran supply line 50, but other screw type or conveyor type may be adopted. Is possible. Even in the air flow conveyance system, since a certain amount of rice bran is derived from the metering feeder side, it can be quantitatively fed to the downstream heating / hydrolyzer 90.

  In addition, it is possible to arrange a foreign substance removing device such as a rotary shifter (not shown) in front of or behind the fixed amount feeder 70 as necessary. The rotary shifter can screen powdery rice bran and unnecessary foreign matter (for example, stone, broken rice, etc.) with high accuracy by horizontal circular movement of the sieves stacked in multiple stages.

  In the warming / watering machine 90, the rice bran is subjected to (1) heating and (2) hydration as a pretreatment step for pressing. The heating / watering machine 90 is a device for adding heat and moisture to rice bran. The purpose of adding heat and moisture to the rice bran is to sterilize the rice bran and deactivate the enzyme, and to improve the subsequent pressing efficiency.

  The rice bran that has been sent in a certain amount is first sterilized and heated in a relatively short time in the heating / watering machine 90. It is preferable to adjust the temperature of the rice bran by the heating / hydrolyzing machine 90 so that the temperature of the rice bran becomes 100 ° C. or higher and 130 ° C. or lower. This is because when the temperature of the rice bran is higher than 130 ° C., the protein and starch in the rice bran are deteriorated, which is not preferable from the viewpoint of maintaining the quality.

  In addition, after (1) heating and (2) hydration treatment of rice bran by the heating / watering machine 90, the rice bran is subjected to (3) pressurization (4) by a granulator (not shown), for example, as necessary. ) Granulation, (5) Voltage application is also possible. For example, the granulator applies pressure and voltage to the charged rice bran to granulate the rice bran.

  The purpose of pressurizing the rice bran is not only for granulating the rice bran but also for the purpose of facilitating the flow of electricity to the rice bran. Rice bran is difficult to conduct electricity as a basic property. In the granulator, by applying heat, moisture, and pressure to the rice bran, it is possible to efficiently pass an electric current through the rice bran.

  The purpose of applying voltage to the rice bran is to destroy the oil body in the cells of the rice bran so that the oil in the rice bran can easily flow out. Oil in rice bran is present in rice bran in a state of being wrapped in a phospholipid called an oil body. Therefore, when extracting oil from rice bran, it is necessary to destroy this oil body. The granulator destroys the oil body in the rice bran by applying a voltage to the rice bran while applying heat, moisture, and pressure. Thereby, when the rice bran granulated by the granulator is squeezed with the downstream press 110, the oil extraction rate of the rice bran is improved. The voltage applied to the rice bran is, for example, a voltage around DC 100V.

  The purpose of granulating rice bran is to efficiently squeeze the rice bran with a downstream press. In order to squeeze the rice oil out of the rice bran by pressing, it is preferable to secure a flow path through which the rice oil flows. Therefore, before the rice bran is squeezed, the granulator performs granulation processing so that a flow path through which rice oil flows between the rice brans is ensured even during the squeezing process in the squeezing machine 110. In addition, it is preferable that a granulator is equipped with a heat retention mechanism so that the rice bran heated with the heating / hydrolyzer 90 may not cool.

  Further, if necessary, a pulverizer can be disposed on the downstream side of the granulator. The granulated rice bran is pulverized to a particle size of about 1 mm by a pulverizer and weighed to a certain amount.

  Furthermore, it is desirable to arrange a roasting machine (kettle) 100 for heating, drying and roasting rice bran, as shown in FIG. The roasting machine is an apparatus for heating, drying and roasting rice bran. The temperature of the heat drying roasting is preferably 100 ° C. or higher and 130 ° C. or lower. The water content of the rice bran that has been heat-dried and roasted is preferably 2% to 8%.

  Next, the rice bran is put into the pressing machine 110 and pressed. Preferably the squeezing is cold squeezed. Here, it is preferable that the temperature of the rice bran used for low-temperature pressing is 100 ° C. or higher and 130 ° C. or lower in order to increase the oil extraction efficiency.

  Particularly preferably, the press 110 receives and squeezes rice bran heated to 100 ° C. or higher and 115 ° C. or lower, more preferably 105 ° C. or higher and 110 ° C. or lower.

  In a general pressing machine, a raw material such as rice bran is squeezed by applying a high pressure of several tens of atmospheres or more. A large amount of heat is generated by the pressure and friction at this time. The pressing machine 110 is configured to efficiently exhaust heat generated during the pressing so that the rice oil crude oil and the defatted rice bran are maintained at 110 ° C. or lower.

  The rice bran squeezed at low temperature by the press 110 is separated into rice oil crude oil and defatted rice bran and output from the press 110, and transported to the rice oil storage can 120 and the defatted rice bran storage bag 130, respectively. In addition, about the structure of the storage tank for collection | recovery of rice oil crude oil, and the storage tank for collection | recovery of defatted rice bran, it does not specifically limit and may be arbitrary. For example, a regular metal or synthetic resin metering tank is used for rice oil crude oil, and a flexible container bag or a metal or synthetic resin storage tank is used for defatted rice bran. obtain.

  In addition, the amount of rice oil crude oil collected in the rice oil storage can 120 and the amount of defatted rice bran collected in the defatted rice bran storage bag 130 are, for example, a liquid level sensor using infrared rays, a weight sensor, etc. Monitoring system using an automatic computing device such as a microcomputer can be used, and a monitoring system that issues a notification signal (for example, sound or lighting of a lamp, etc.) can be provided if necessary when the specified amount is reached. It is.

  Next, the rice oil manufacturing method using the rice oil manufacturing plant which concerns on this invention as mentioned above is demonstrated.

  In the rice oil production method according to the present invention, the rice bran derived from the rice bran separation part of the rice milling process is continuously conveyed to the oil extraction process by airflow conveyance through the pipeline, It is characterized by squeezing rice bran after heating and water addition (more preferably, roasting).

  The general flow, conditions, etc. of the rice oil production method according to the present invention are as described together with the description of the embodiment of the rice oil production plant according to the present invention described above. An embodiment in which the rice bran is squeezed within 20 hours from the rice milling process, and further within 4 to 5 hours may be included as a preferable one.

  That is, in the present invention, the rice bran derived from the rice bran separating part of the rice milling process is conveyed directly and continuously to the oil extraction process by airflow conveyance through the pipe line, and thus the rice milling process in such a short time. It is possible to use the rice bran obtained in squeezing treatment, suppress the deterioration of the quality of the rice bran that is oxidized and denatured immediately after the rice milling process, keep the low acid value, and in terms of quality, flavor and nutritional characteristics An excellent rice oil can be produced stably.

  In the above rice oil production method, the amount of rice bran that is air-flowed through the pipeline from the rice milling process, the amount of feed from the metering feeder in the oil extraction process, etc., is the scale of each device in the rice milling process and oil extraction process. The rice bran can be adjusted accordingly, and is not particularly limited. For example, when the rice bran is conveyed by air flow through a pipe line from the rice milling process, the rice bran is conveyed by a conveyance amount of about 500 to 600 kg / h. If the delivery rate with the metering feeder is about 200 to 300 kg / h, good continuous processing can be achieved.

  Furthermore, in one embodiment of the present invention, the rice bran used can be obtained from a single variety of raw rice. As described above, in the present invention, the rice bran derived from the rice bran separation part of the rice milling process is directly led to the oil extraction process by airflow conveyance through the pipe line, and thus recovered from the rice milling plant as in the past. Unlike the case where rice bran is transported and transported to a refinery, it is easy to specify the raw rice from which the rice bran to be used is derived, and it does not fall into the situation where other varieties are mixed or the variety is unknown. By identifying the raw rice varieties from which rice bran originates, it becomes possible to stabilize the quality and ingredients of the obtained rice oil, and it is possible to separate the quality and ingredients of rice oil by the raw material varieties, Higher value-added products can be obtained.

  Rice bran generally has a moisture content of 13 to 15%, an oil content of 18 to 20%, a solid content of 65 to 70%, a wax content of 0.9 to 1.6%, and a phospholipid of 0.3 to 0.00. In the present invention, the rice bran introduced from the milled rice section to the fixed quantity feeder 70 in the oil milling section is the conventional oil refinery. Compared to rice bran that was transported to the factory and used as a raw material, although there is not much difference in these points, there is a difference in that the amount of free fatty acid hydrolyzed triglyceride, which is the main component of fats and oils, is small, It seems to contribute to the improvement of the quality of the rice oil obtained.

  The pressed rice oil according to the present invention is a rice oil obtained by the above-described method for producing rice oil, and the acid value of the crude oil after pressing is 15 or less, preferably 10 or less, more preferably 5 or less. It is characterized by this.

  As described above, the rice bran derived from the rice bran separation part of the rice milling process is continuously transferred to the oil extraction process by airflow conveyance through the pipeline, and the use of fresh rice bran makes it possible to influence the alteration of the rice bran used as a raw material. High quality rice oil can be prepared without receiving it. In the conventional refinery plant, even if it is the best case, the effect of improving the quality of rice oil according to the present invention is remarkable as compared with the acid value of about 20.

  Moreover, in one Embodiment of the press rice oil which concerns on this invention, as above-mentioned, it shall be obtained from a single kind of raw material rice. By specifying the varieties of raw rice from which rice bran is derived, the quality, ingredients, and the like are stabilized, resulting in a product with high added value.

  The pressed rice oil thus obtained is then physically purified, if necessary, usually using degumming, dewaxing, bleaching and steam distillation. Although not particularly limited, for example, degumming can be carried out by two addition steps of stirring with 1-5% by weight of water and then stirring with 0.02-1% by weight of phosphoric acid. The temperature is held at about 82 ° C. to 88 ° C. for 10 minutes. The sludge containing gum is then removed by centrifugation. The degummed oil is cooled to 5-8 ° C. and held for 24 hours. The dewaxed oil forms a layer on the decantable wax using a vacuum pump. Bleaching is performed, for example, according to official AOCS method 6c8a-52. Physical purification is performed by steam distillation at about 250 ° C. and around 3 mmHg for about 2 hours.

  Hereinafter, the present invention will be described more specifically based on examples.

Example 1
Rice oil was produced using a rice oil production plant as shown in FIG.
As rice used as a raw material, Akitakomachi produced in Akita is used, and the rice bran obtained from the rice bran separation section is refined in the rice milling section at a rate of about 500 to 600 kg / h from the rice bran supply line 50a. Sent out. The rice bran once stored in the rice bran storage tank 60 is sent to the metering feeder 70 at a rate of about 200 to 300 kg / h through the rice bran supply line 50b and further added in a stable amount of 240 kg / h. It is supplied to the temperature / water machine 90 and the heat-drying roasting machine 100 where the water content of the rice bran is heated to about 6% and the temperature is 105 ° C., sent to the pressing machine 110, and squeezed at 10 MPa. Crude oil was extracted. As temperature conditions at the time of pressing, the temperature was adjusted to 20 ° C. at the start of pressing and to be about 120 ° C. which is the final temperature 60 minutes after the start of pressing.
In addition, the pressing process was performed within 4 to 5 hours immediately after the rice milling process.

  As a result, about 10% by mass of crude rice oil was obtained by pressing with respect to the mass of the rice bran raw material, and when the acid value of the crude rice oil was measured by the standard oil analysis test method, the acid value was 6 It was found that the acid value was very low.

Example 2
Rice oil was produced in the same manner as in Example 1 except that the retention time of the rice bran in the plant from the rice milling process to the pressing treatment was changed to 18 hours.
As a result, the same crude rice oil as in Example 1 was obtained by pressing, and when the acid value of the crude crude oil was measured by the same method as in Example 1, the acid value was 12.88. .

Comparative Example 1
For comparison, as a conventional example, for rice bran that has been transported by truck from a rice mill (elapsed time from polished rice is about 48 to 96 hours), the same transport amount, heating, Rice oil crude oil was produced under humidification, roasting conditions and pressing conditions. About 10% by mass of crude rice oil was obtained by pressing with respect to the mass of the rice bran raw material, and when the fatty acid oxidation degree of the crude rice oil was measured by the same method as in Example 1, the acid value was 33.6 and over 20.

Example 3
In Example 1, crude rice oil was produced in the same manner as in Example 1, except that the rice varieties that had been polished were replaced with Hokkaido Natsutoshi.

  As a result, as in Example 1, about 10% by mass of crude rice oil was obtained by pressing with respect to the mass of the rice bran raw material, and the acid value was 5.43. The acid value was very low.

  As described above, the present invention has been described based on the embodiments. However, the present invention is not limited to the embodiments exemplified above, and does not depart from the configuration and concept of the present invention described in the claims. It is easily understood by those skilled in the art that various modifications and changes can be made therein, and these aspects are also included in the present invention.

DESCRIPTION OF SYMBOLS 1 Rice oil production plant 10 Brown rice storage part 20 Rice polishing part 30 Rice bran separation part 40 White rice storage part 50 Rice bran supply line 51a, 51b Air blow pump 60 Rice bran storage tank 70 Metering feeder 80 Metered rice bran supply line 90 Heating and adding machine 100 Roasting Roasting machine (kettle)
110 Press

Claims (7)

A rice oil production plant,
A rice mill section comprising at least a brown rice storage section for storing brown rice, a rice milling section for milling brown rice, a rice bran separating section for removing rice bran from milled rice to white rice, and a white rice storage section for storing the obtained white rice;
A rice bran supply line that is directly connected to the rice bran separating unit of the rice milling section and that conveys the rice bran derived from the rice bran separating unit by airflow conveyance, and a certain amount of rice bran conveyed by the rice bran supply line is introduced. A fixed quantity feeder for sending rice bran, a fixed quantity rice bran supply line having a pipe for conveying a certain amount of rice bran sent by the fixed quantity feeder, and heating for heating and adding water to the rice bran supplied from the quantitative rice bran supply line A rice oil production plant comprising a water mill and an oil extraction section having at least a pressing machine for pressing rice bran supplied from the heating / water machine.   A rice bran storage tank is provided in the middle of the rice bran supply line. The rice bran storage tank is divided into a system for conveying rice bran from the upstream side to the rice bran storage tank and a system for conveying rice bran from the rice bran storage tank to the downstream side. The rice oil production plant according to claim 1, wherein   The rice oil production plant according to claim 1 or 2, wherein a roasting machine for heating, drying and roasting rice bran is further provided between the heating / watering machine and the press.   The rice bran derived from the rice bran separation part of the rice milling process is continuously conveyed to the oil pressing process by air flow through the pipe, the amount of rice bran supplied is quantified, the rice bran is heated and hydrated, and then the rice bran is compressed A method for producing rice oil, comprising:   The rice oil production method according to claim 4, wherein the rice bran is squeezed within 4 to 5 hours from the milling process.   A rice oil obtained by the method according to claim 4 or 5, wherein the acid value of the crude oil after pressing is 10 or less.   The compressed rice oil according to claim 6, wherein the raw rice is of a single variety.