JPS6347429B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for cooling and turning boiled rice or its processed product into single grains, and the resulting cooked rice can be turned into single grains even after freezing, and can maintain the quality at the time of manufacture for a long period of time. It is.

BACKGROUND ART Many types of frozen rice, mainly rice such as pilaf and fried rice, have been known. Normally, when producing frozen cooked rice, cooked or steamed rice is cooked as is or with ingredients added to it, placed in a container and frozen into a plate shape, and then crushed after freezing. Methods have been taken, such as forming the agglomerates into granules, or deagglomerating and cooling the agglomerates in advance, partially freezing the surface of the agglomerates, and then bringing the agglomerates into contact with a refrigerant such as liquid nitrogen or liquefied carbon dioxide to freeze the entire body.

However, the former method involves the destruction of rice grains during crushing, which reduces commercial value, while the latter involves two-stage freezing, which causes ice particles to become denser and denser within the rice grains, resulting in lower quality and requiring a large amount of refrigerant. Therefore, it is not an advantageous method as it increases the manufacturing cost.

The present inventors solved the drawbacks of conventional frozen rice,
As a result of our research to create a pre-processing device for frozen cooked rice that is inexpensive and does not deteriorate in quality even after long-term storage, we deagglomerate rice that has been cooked or cooked using a conventional method using a deagglomeration machine, making each grain one by one. The rice grains separated into grains are cooled with chilled circulating air while being stirred with a deagglomeration rod in a layer thickness of approximately 5 mm, and the temperature of the cooked rice is controlled to be 0 to 5°C to remove as much free moisture as possible, and then cooled. It was discovered that it was necessary to freeze cooked rice after dehydration, and as a device suitable for this method, for example, a net conveyor was installed in the lower open part of a hopper with a stirring rod and rotated. The cooked rice is taken out from the side feeding part in a layer thickness of about 5 mm, and placed on the running path of the net conveyor.
A stirring rod is provided to stir the removed cooked rice, and an air circulation chamber is provided to surround the stirring rod and the portion of the net conveyor opposite thereto;
a first loosening cooler that circulates the cooled air through the net conveyor; and a second loosening cooler comprising a ribbon screw conveyor with a jacket and having an air inlet on the outside for discharging the cooked rice cooled by the first loosening cooler.
Supply it to a loosening cooler, remove free moisture, and reduce the temperature to 0~
They completed a device that feeds cooked rice cooled to 5°C to a freezing device.

An example of the present invention will be described with reference to the accompanying drawings. Reference numeral 1 indicates a machine frame of a first loosening cooler, 2 a driving pulley driven by a motor (not shown), and 2' a driven pulley. A net conveyor 3 is stretched between the pulleys 2 and 2' and is rotated in the direction of the arrow.The net conveyor 3 is preferably made of stainless steel, and is usually made of 10 to 20 meshes. Further, guide plates 4, 4 are provided on both sides of the lower side of the feed side of the net conveyor 3, and auxiliary guide plates 5, 5 are provided between the guide plates 4, 4.
It helps the rotation of the net conveyor 3. Side plates 6, 6 are raised above the guide plates 4, 4 and fixed to the machine frames 1, 1, so as to cover both sides of the net conveyor 3. A hopper 7 is arranged above the net conveyor 3 on the side of the driven pulley 2' to store the cooked cooked rice 8. The hopper 7 has its lower part open and faces the net conveyor 3, and the side portion of the hopper 7 stores the cooked rice 8. The feeding side is open and the partition plate 9 is fixed so that the mounting position can be freely adjusted. Furthermore, a pair of rotating shafts 10, 10' are provided on both side walls of the hopper 7.
The gears 11 and 11' fixed to the ends of the shafts 10 and 10' are meshed and rotated in the same direction, and the shaft 10 is directly connected to the shaft of an electric motor (not shown) and rotated as necessary. . Therefore, when rice 8 is put into the hopper 7 and the shaft 10 is rotated, the shaft 1
A large number of deagglomeration rods 12 fixed at 0,10' rotate,
The cooked rice 8 is loosened and delivered from the partition plate 9 by the rotation of the net conveyor 3. At this time, the gap between the partition plates 9 is set to about 5 mm, so the layer thickness of the cooked rice is as thin as about 5 mm. When the net conveyor 3 rotates further, it is leveled by a layer thickness adjustment leveling blade 13 provided above it, but the leveling blade 13 usually has a length of 50 mm, and its shaft 14 is directly connected to an electric motor (not shown). , rotates at a speed of approximately 100 rpm so as to counter the movement of the fed cooked rice 8, and the distance between the end of the blade 13 and the net conveyor 3 is approximately 5 rpm.
It is in mm. Therefore, the surface of the cooked rice 8 is leveled to a layer thickness of approximately 5 mm, and both sides of the cooked rice 8 come into contact with the side walls 6. When the net conveyor 3 rotates further, the cooked rice also moves further, and the air circulation chamber 1
5, the air circulation chamber 15 is located between the layer thickness adjusting leveling blade 13 and the pulley 2, and surrounds a part of the feed side of the net conveyor 3 in the left, right, front and rear. A partition 16 is provided on the upper front side and both left and right sides, and air circulation paths 18, 18 are opened between the outer walls 17, 17. The air is directed toward the inside of the partition 16. Also, inside the partition 16, the fan 19
An air cooler 20 is provided below the air cooler 2.
0 has a brine inflow pipe 21 and a brine outflow pipe 22.
brine is introduced from the outside to cool it to a desired temperature, and it also comes in contact with the circulating air from the fan 19 to cool it and make it saturated cooling air. Further, a crusher 23 is located below the air cooler 20 and above the net conveyor 3.
A large number of pulverizers 23 are arranged horizontally, but the pulverizer 23
4, a crushing rod 25 installed on the shaft 24, and the shaft 24
The tip of the crushing rod 25 is close to the surface of the net conveyor 3 and rotates in the feeding direction of the net conveyor 3. Therefore, the stirring rod 25 stirs the cooked rice 8 that has been leveled by the leveling blade 13 while sending it in the feeding direction, and uniformly cools each rice grain one by one by receiving the cold air from the cooler 20. That's what I do. At this time, if the layer thickness of the cooked rice significantly exceeds 5 mm, it will be difficult to cool the rice uniformly even if the rotation of the net conveyor 3 is slowed down, and there will be uneven drying, which will impair the appearance of the product. On the other hand, if the layer thickness is significantly thinner than 5 mm, there is a drawback that the performance of the device decreases.

As mentioned above, the air that has exchanged heat with the cooked rice grains 8 escapes downward and rises through the circulation path 18, and the above operation is repeated again. In addition, 27 in the figure indicates a damper, which takes in outside air and circulates the air as necessary. The net conveyor 3 rotates further, and the cooked rice 8 is cooled and transferred to the air circulation chamber 15.
When it is unloaded, it is unloaded via a chute 28 provided at the end of the pulley 2.

The cooked rice grains carried out from the chute 28 are transferred to a second loosening cooler, which is composed of a ribbon screw conveyor and has a cylinder 30 below the inlet 29. A jacket 31 is fixed on the outside, and one end of the jacket 31 has a refrigerant inlet 32 and a refrigerant outlet 33. When the refrigerant is brine, the refrigerant inlet 32 is provided on the lower side as shown in the figure, but when the refrigerant is liquid nitrogen, it is preferably provided on the upper side. A shaft 34 is passed through the center of the cylinder 30, one end of which is directly connected to a drive motor 35, and the other end supported by a bearing 36. Crushing rods 37, 37 are installed at regular intervals on the circumferential surface of the shaft 34, and are brought into contact with the inner wall of the cylinder 30, and the ribbon screw 38 is rotated in the direction of the arrow. vinegar. cylinder 3
A discharge port 39 is provided on the opposite side of the inlet 29 of 0, an opening/closing door 40 is provided below the discharge port 39, and further,
A ventilation port 41 is opened on the side and communicated with a blower (not shown). Therefore, the cooked rice grains 8 from the inlet 29 are sent toward the discharge port 39 by the ribbon screw, during which time they come into contact with the inner wall of the cylinder 30 and are cooled. It comes into contact with air from 41, is maintained at a temperature between 0 and 5°C, and is discharged from an outlet 39. At this time, it is better to avoid strong cooling below 0°C, as this will cause the particles to freeze and solidify. Furthermore, the air in the ventilation opening 41 escapes through the inlet 29.

The cooked rice grains 8 that have been crushed and cooled in the manner described above are frozen using conventional methods such as leaving them in a freezer or mixing them with liquid nitrogen, dry ice powder, etc. There is no problem in adopting it.

As described above, by using the apparatus of the present invention, cooked rice is cooled while being made into single grains by moderate stirring, cooling, and removal of water while removing surface water under ventilation cooling, and after cooling, the conventional method is used. It can be frozen and made into frozen cooked rice. Now, to explain an example of the present invention using an experimental example in which cooked rice with rice and ingredients was stirred and cooled, the moisture content immediately after cooking was 51%, the product temperature was 90℃, and this was set as an average residence time of 10 to 15 minutes for cooling. machine 2
0 and the refrigerant temperature at the refrigerant inlet 32 were adjusted so that the temperature of the discharged product from the discharge 39 was 0°C to 4.0°C. At this time, immediately after cooking, shoot 2
8, and 5g of each sample from the outlet 39 into a 2.5cm
Store in a container with a diameter of 5 cm and compress it to a thickness of 1 cm.
After making the same volume, it was frozen at -20°C and measured with a texture meter (manufactured by General Foods), and the hardness at that time was taken as the binding strength. Comparing the binding force immediately after cooking and the binding force at the chute 28 and outlet 39, the binding force decreases due to cooling.
It has been found that this is due to the loosening temperature in each process having an important influence, especially at temperatures below 10°C, the binding strength suddenly decreases, and at 0-5°C there is little change, compared to the product temperature at 0-5°C. It turns out that it is important to manage Furthermore, the results of moisture change showed that when cooled samples with moisture removal rates of 0%, 2%, and 4% were prepared and a sieving test was conducted using a rotary sieving device with 1-mesh and 3-mesh sieves stacked on top of each other, The amount of water that passes through the 3 mesh is almost 0%, while at 2% it is about 42%, and at 4% it is about 73%.
%, and it has been found that removing as much water as possible is more advantageous in making cooked rice into single grains, and when such rice grains are frozen by a conventional method, frozen rice of extremely high quality can be obtained.

The cooked rice obtained by the present invention is in pieces and has a
It is cooled to 5℃, which allows freezing to occur extremely quickly when transported into the freezer as a thin layer, and does not require the use of large amounts of expensive refrigerant or large-scale equipment as in the past. In addition to being economical, frozen cooked rice can be re-frozen and filled into containers as it is, and frozen cooked rice can be produced at a high yield without deteriorating quality.

This will be explained below using examples.

Example 1 For cooked rice, 5 kg of rice, 5.5 kg of water, 0.5 kg of oil, and 1.5 kg of ingredients were placed in a pot and cooked over direct heat at room temperature for 30 minutes. At this time, the moisture content was approximately 50%. Using the device shown in the figure, transfer the cooked rice to hopper 7 (at this time, the product temperature is 80°C) and move the net conveyor at a speed of 0.5 to 1 per minute.
Rotate at a speed of m, and the thickness of the cooked rice on the partition plate 9 is 10 to 15 mm.
It was paid out as mm. In addition, brine is sent to the cooler 20, the outlet temperature of the cooler 20 is 5°C, the blade length of the crusher 23 is 50 mm, the rotation is 100 rpm, and the average residence time in the air circulation room is 2 minutes. The product was cooled in seconds and controlled so that the product temperature on the chute 28 was 5°C and the moisture content was 48%. Also, the rotation of the ribbon screw on the ribbon screw conveyor that receives this is 40 rpm.
brine at -30 to -35℃ is supplied from the refrigerant inlet 32, and air at 0 to 5℃ is supplied from the ventilation port at a rate of 5 degrees per minute.
Supplied at a rate of ~ ^10m3 . As a result, 10 kg of cooked rice was obtained which had been cooled to a temperature of 1°C. Next, this was placed in a shallow dish and frozen in a -40°C freezer for 24 hours. As a result of re-fragmenting the obtained frozen cooked rice, it was easily made into single grains. Pack this in a 100g package and store it for 7 days.
When the product was stored at ℃, thawed, and cooked, the quality was extremely good, with no lumps or lumps, and no loss of commercial value.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of the apparatus of the present invention, FIG. 2 is a sectional view taken along line AA in FIG. 1, FIG. 3 is a longitudinal sectional view of the ribbon screw conveyor, and FIG. 4 is taken along line BB in FIG. FIG. 1... Machine frame, 2, 2'... Pulley, 3... Net conveyor, 7... Hopper, 9... Partition plate,
12... Deagglomeration rod, 13... Leveling blade, 15...
Air circulation chamber, 19... fan, 20... air cooler, 23... agitator, 30... cylinder, 32... refrigerant inlet, 39... discharge port, 41... ventilation port.

Claims (1)

[Claims] 1. A hopper with loosening blades for adding cooked rice,
A net conveyor that rotates below the lower opening of the hopper and pulls out cooked rice grains to a uniform thickness, a stirring blade provided on the running path of the net conveyor, and a portion surrounding the net conveyor that opposes the stirring blade. A single grain of cooked rice consisting of a first loosening cooler consisting of a cold air circulation chamber that cools and circulates air, and a second loosening cooler comprising an air inlet on the discharge side of a ribbon conveyor with a refrigerant jacket. conversion device.