JPH11346746A - Production of foamed rice molded product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a foamed rice molded product, capable of producing the extremely dense and lightweight foamed rice molded product having an excellent crispy texture by plasticizing and melting rice and subsequently jetting the plasticized rice. SOLUTION: This method for producing a foamed rice molded product comprises feeding a prescribed amount of rice having a controlled water content of 7-16% from a material feeder 8 into a cylinder barrel 2, plasticizing and melting the fed rice at 120-180 deg.C due to frictional heat or shear heat generated by the rotation of a screw 10 on the basis of a plasticization motor 11, due to the heat of a heater 3, etc., sequentially transferring and accumulating the plasticized rice in an accumulation chamber 4, measuring the amount of the plasticized rice in the accumulation chamber 4 with a higher pressure than the saturated vapor pressure of water, and subsequently forward driving the screw 10 by the use of a jetting motor to jet the plasticized rice from the hole of a nozzle 5 into the atmosphere. The plasticized rice is thus jetted and simultaneously foamed by the pressure of steam to give the foamed rice molded product (snack food) which is extremely dense and lightweight and has a specific crispy texture.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a foamed rice product, and more particularly, to a method for producing a rice foam molded product having various shapes which are dense and highly foamable. It is about.

[0002]

2. Description of the Related Art As a method for producing a foamed rice product, a method of processing using an extruder is conventionally known. In this conventional production method, rice and water are supplied into an extruder. The rice is plasticized (gelatinized) by heating and pressurizing in the extruder, and the plasticized (gelatinized) rice is extruded into the atmosphere from a die attached to the tip of the extruder, so that the hole diameter of the die is increased. A foam that has been foamed several times as large as the above is manufactured.

For example, when producing a rice foam using a twin-screw extruder having a screw outer diameter of 52 mm, when the supply amount of rice is 150 kg / h and the hole diameter of the die is 3 mm, the diameter of one hole is about 18 mm. Rice foam (snack food) with good quality is produced. The extrusion speed at the die hole at this time is about 5 (when the specific gravity of the plastic is 1 g / cm ³ ).
It was 89 cm / sec.

[0004] Foamed rice food produced using an extruder as described above has a crisp texture, although a slight difference in texture and the like appears depending on the type of rice to be treated. Also, the more the plasticized (gelatinized) rice is extruded from the die hole at high speed and high pressure in the extruder,
It foams densely and becomes a foam with increased crispness.

[0005]

However, the above-described conventional manufacturing method has the following unsolved problems. That is, in a manufacturing method using an extruder, there is a limit to the material that can be processed depending on the size of the extruder. Therefore, in the production conditions of a certain product, in order to further increase the extrusion speed, the extrusion hole of the die must be reduced,
This makes it impossible to obtain a product of the desired size. Also, in order to obtain a foam having large dimensions, it is necessary to enlarge the extrusion hole of the die.However, if the extrusion hole of the die is enlarged, the material pressure at the die part becomes lower because the opening area of the hole becomes larger. Further, since the extrusion speed is slowed down, the extruded product is insufficiently foamed, so that only a heavy, crispy and extremely poorly textured product can be obtained. As described above, it is difficult to produce a densely foamed rice foam with a certain size by a conventional production method using an extruder.

Accordingly, the present invention has been made in view of the above-mentioned unsolved problems of the prior art, and is extremely dense and compact by injecting a plasticized melt obtained by plasticizing and melting rice. It is an object of the present invention to provide a method for producing a rice foam molded article which is capable of producing a light and crisp rice foam molded article excellent in texture.

[0007]

In order to achieve the above object, a method for producing a foamed rice product of the present invention comprises supplying rice to an injection device, heating the rice to a temperature of 120 to 180 ° C., and plasticizing and melting the rice. Injecting this plasticized product to produce a foamed molded article.

In the method for producing a foamed rice product of the present invention, rice is supplied into a cylinder barrel of an injection device, and frictional heat, shearing heat and heat applied from a heating heater by rotation of a screw in the cylinder barrel are supplied. The rice is heated to 120 to 180 ° C. to be plasticized and melted, etc., and the plasticized rice is accumulated and measured in the accumulation chamber in the cylinder barrel at a pressure higher than the saturated vapor pressure of water, and then the screw is screwed. The plasticized rice is injected into the atmosphere through a nozzle hole by the forward drive of the nozzle to produce a foamed molded product.

In the method for producing a foamed rice product of the present invention, it is preferable that the moisture of the rice is adjusted to 7 to 16%.

[0010]

According to the method for producing a foamed rice product of the present invention, a predetermined amount of rice having a moisture content adjusted to 7 to 16% is supplied into a cylinder barrel, and the screw is rotated by a plasticizing motor. Then, the rice is heated to 120 to 180 ° C. by friction heat, shear heat, heat applied from a heater or the like to plasticize and melt the rice, and is sequentially sent to a storage chamber for storage. In the accumulation chamber, the plasticized rice is metered at a pressure higher than the saturated vapor pressure of water. Thereafter, the plasticized rice is injected into the atmosphere from the nozzle hole of the nozzle by advancing a screw by an injection motor, and foaming is caused by steam pressure simultaneously with the injection. As a result, an extremely dense and lightweight rice foam molded article (snack food) excellent in crisp texture can be produced. In addition, by changing the shape of the nozzle, rice foam molded products of various shapes can be produced, and even in a rice foam molded product having a large size, the rice foam molded product is also extremely dense, lightweight, and excellent in crispness. Good things can be obtained.

[0011]

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram schematically showing an example of an apparatus for producing a rice foam molded article suitable for the method for producing a rice foam molded article according to the present invention.

In FIG. 1, an injection device 1 as a device for producing a foamed rice product has a cylinder barrel 2 in which a screw 10 is rotatably disposed so as to be able to advance and retreat in the axial direction. , A plurality of heaters of which the temperature is individually controlled, are provided. The heater 3 near the material supply port 2a provided at the rear of the cylinder barrel 2 further includes water. A jacket 9 is provided so that the temperature can be controlled by controlling the circulation.

A storage chamber 4 is secured at the front of the cylinder barrel 2 as a position in front of a screw 10, and a nozzle 5 is attached to the tip of the cylinder 5 in a conventionally well-known manner. As an opening and closing mechanism for opening and closing the hole, a valve 6 driven to be opened and closed by a valve driving device 7
Is provided. The valve 6 closes the nozzle hole of the nozzle 5 so that the plasticized material can be accumulated and measured in the accumulation chamber 4 at a pressure higher than the saturated vapor pressure of water. It acts to interrupt the flow of material in the state.

A material supply feeder 8 is provided above a material supply port 2a provided at a rear portion of the cylinder barrel 2 so as to supply a predetermined amount of material.

A plasticizing motor 11 for rotating the screw 10 and an injection motor 12 for driving the screw 10 back and forth in the axial direction are provided at the rear of the cylinder barrel 2. 12 is
The ball screw 14 is rotated via the timing belt 13, and is converted into a linear motion of the screw 10.

Next, a method of manufacturing a foamed rice product using the above-described injection device 1 will be described.

First, the position where the screw 10 is retracted, that is, the metering completion position, is set by a controller (not shown) based on the size and capacity of the molded product to be manufactured, and the amount of supply from the material supply feeder 8 is calculated. Is set so that rice, which is an injection material suitable for the above, is supplied through the material supply port 2a.

After these various settings are completed, the measuring process by the injection device 1 is started. In response to a signal from the controller, the valve driving device 7 is driven to operate the valve 6 and close the nozzle 5. Next, the plasticizing motor 1
1 is started, and the screw 10 is driven to rotate at a predetermined speed. At the same time, a predetermined amount of rice as an injection material is supplied from the material supply feeder 8 into the cylinder barrel 2 via the material supply port 2a. Here, the water contained in the rice has a function as a foaming agent. The supplied rice is screw 1
120-180 ° C. due to frictional heat, shearing heat due to rotation of 0, and heat applied from the heaters 3, 3,...
, And is plasticized (gelatinized), gradually transferred to the accumulation chamber 4 according to the rotation of the screw 10, and accumulated and measured in the accumulation chamber 4. When the measurement proceeds and the screw 10 is retracted to the measurement completion position, the plasticizing motor 11 is stopped, and the measurement ends. In this metering process, the plasticized rice is accumulated at a pressure higher than the saturated vapor pressure of water in the accumulation chamber 4.
Is weighed.

Subsequently, the valve driving device 7 is driven to operate the valve 6 to open the nozzle 5 and the injection motor 1
2 is driven. The rotational movement of the injection motor 12 rotates the ball screw 14 via the timing belt 13,
This is converted into a linear motion of the screw 10, and the screw 10 is driven forward in the injection direction. By the forward movement of the screw 10, the plasticized rice weighed in the accumulation chamber 4 is ejected from the nozzle hole of the nozzle 5. The plasticized rice injected into the atmosphere is foamed simultaneously with the injection by the steam pressure. As a result, a foam foamed several times the diameter of the nozzle hole is produced. After the injection of a predetermined amount of rice in the plastic state is completed, the nozzle hole of the nozzle 5 is closed by the operation of the valve 6 by the driving device 7. Then, by repeating weighing and injection in the same procedure,
A foamed rice product (snack food) can be manufactured.

Next, a preferred embodiment of the method for producing a foamed rice product according to the present invention will be described.

The rice used for molding was Sasanishiki, and the water content was adjusted (humidity control) to be 13.5%.

An electric injection molding machine (manufactured by Nippon Steel Works: J75EL) was used as a molding and manufacturing apparatus for the foamed rice product. The molding conditions were: injection rate: 176 cm ³ / sec, cylinder temperature: 40/120/170. ° C, nozzle temperature: 13
Molding was performed at 5 ° C. and a nozzle hole diameter of 3 mm. At this time, the screw outer diameter was 32 mm, and the injection speed at the nozzle hole was about 2489 cm / sec. The rice foam molded product (snack food) thus obtained was a light-weight, dense foam having small cell cells constituting the foam, and was excellent in crispness.

Further, the same injection molding machine was used to prepare a nozzle hole diameter: 6
When a foam molded article is manufactured by attaching a nozzle of
The injection speed at the nozzle hole was about 622 cm / sec. Similarly, a large-diameter rice foam molded product (snack food) having a large size in a foamed state excellent in crispness could be produced.

By the way, in the production method using a conventional extruder, when considering the extrusion conditions when producing a rice foam using a twin-screw extruder having a screw outer diameter of 52 mm, the supply amount of rice is 150 kg. / H, die hole diameter 3mm
In this case, a good rice foam (snack food) having a diameter of about 18 mm is produced in one hole, but the extrusion speed in the hole of the die in this case is (the specific gravity of the plastic material is 1 g).
/ Cm ³ ) was about 589 cm / sec.
That is, according to the method for producing a rice foam molded article of the present invention, it is possible to produce a rice foam molded article at about four times the speed when the pore diameter is the same as compared with the conventional method using an extruder. it can. In the conventional method using an extruder,
The extrusion speed was set to the injection molding machine described above (injection speed: about 2400
cm / sec), a treatment of about 600 kg / h is required, which is impossible with a twin-screw extruder having a screw outer diameter of 52 mm.

In the method for producing a foamed rice product according to the present invention, the same Sasanishiki was used as a raw material to adjust (humidify) various water contents, and molding was performed. For rice having a water content exceeding 16%, Shrinkage occurred after foaming, resulting in a foam with poor crispness. In addition, the water content is 7
%, The load on the drive motor of the apparatus was increased, and the resulting molded article was found to contain a large amount of burnt smell, which was not suitable for forming snack foods.

[0027]

As described above, according to the method for producing a foamed rice product of the present invention, the following remarkable effects can be obtained.

(1) A lightweight and extremely dense foam which cannot be obtained by extrusion molding can be obtained, and the wall itself for forming bubbles is thin, so that the rice foam having a very good crispy texture can be obtained. A molded article can be obtained.

(2) By changing the shape of the nozzle,
Foams of various shapes can be obtained, and a foamed rice foam having a very good crispy texture can be obtained even with a foam having a large diameter.

(3) By using an injection machine, unlike a conventional extruder, the operation is extremely simple, and a rice foam as a raw material is put into a hopper to automatically and rapidly produce a foamed rice product. be able to.

[Brief description of the drawings]

FIG. 1 is a configuration diagram schematically illustrating an example of an apparatus for producing a rice foam molded article suitable for the method for producing a rice foam molded article according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Injection apparatus 2 Cylinder barrel 2a Material supply port 3 Heater 4 Storage chamber 5 Nozzle 6 Valve 7 Valve drive device 8 Material supply feeder 9 Jacket 10 Screw 11 Plasticizing motor 12 Injection motor 13 Timing belt 14 Ball screw

Claims (3)

[Claims] 1. Rice is supplied to an injection device and is heated to 120 to 180 ° C.
A method for producing a foamed rice product, characterized in that the foamed product is produced by heating the plasticized product to a temperature of 1. 2. Rice is supplied into a cylinder barrel of an injection device, and the rice is heated to 120 to 180 ° C. by friction heat, shear heat, heat applied from a heater and the like due to rotation of a screw in the cylinder barrel. The plasticized molten rice is stored and measured in the storage chamber in the cylinder barrel at a pressure higher than the saturated vapor pressure of water, and then the plasticized rice is nozzle-opened by the forward drive of the screw. And producing the foamed molded product by injecting the foamed product into the atmosphere. 3. The method for producing a foamed rice product according to claim 1, wherein the moisture content of the rice is adjusted to 7 to 16%.