JPH0426960B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an extruder, and particularly to a die of an extruder used when a continuous structured molded product is extruded using protein-based food raw materials. .

[Prior art]

Food processing using extruders has a long history, appearing in literature as early as the late 1800s. Initially, it was used for dehydration and juice extraction, but gradually it came to be used for processing and molding purposes as well. That is, the material is fed into the screw through the supply port, kneaded, heated, and sent forward, and extruded through the die to give the product its specific shape.

Extruders are broadly classified into single-screw extruders, which have one screw, and twin-screw extruders, which have two screws. Further, twin-screw extruders are classified into various types depending on the degree of engagement between the two screws and the direction of rotation. In the past, extruders were thought of as machines that simply had the functions of compression, kneading, and swelling, but recently, extruders have been viewed as machines with the functions of compression, kneading, and swelling, but recently they have been treated with a wide variety of phenomena, including compression, mixing, kneading, shearing, melting, sterilization, chemical reactions, swelling, etc. Active use of molding, etc. is attracting attention.

A schematic diagram of a conventionally used extruder is shown in FIG. This is the simplest extruder and 3 is a hopper, from which raw materials are supplied. 1 is a cylindrical cylinder barrel, 2 is a screw rotating within the barrel 1, and the screw 2 is rotated by a drive device. The raw material is compressed and kneaded by the rotation of the screw 2, conveyed, and extruded through a die hole of a die 4 provided at the outlet of the barrel 1. The screw tip 2' has a conical shape.

The barrel 2 may be heated from the outside by an electric heater or the like, or the temperature may be controlled by flowing a temperature medium through a gap formed inside the barrel. Further, the principle is fundamentally the same even in a type having a forced feed hopper or a twin screw type extruder having two screws.

Since the purpose of such an extruder was mainly compression, kneading, and molding, the tip of the screw was conical, spherical, or flat, as shown in Figures 5 to 7. It is designed to smoothly transport raw materials from the section to the die. However, when an extruder is used as a chemical reaction machine, especially when used for the purpose of assembling plant proteins, it is necessary to generate an appropriate reaction (for example, an assembling reaction in which proteins join together) after mixing and kneading. It is necessary to do so.

For this purpose, if the screw tip has such a shape, the reaction may not be carried out sufficiently because the mixture is extruded from the die with insufficient kneading. Alternatively, the raw material is not stirred until it reaches the die, and a temperature difference occurs between the raw material moving near the barrel wall and the raw material moving in the center far from the wall.
Non-uniform reaction and overcooking of raw materials near the wall may occur.

[Purpose of the invention]

An object of the present invention is to eliminate the above-mentioned drawbacks and provide an extruder that is optimal for use in obtaining meat-like structured proteins using defatted soybean flour as a raw material.

[Structure of the invention]

The present invention provides a cylinder barrel having a cylindrical shape, a screw having a thread and inserted into the barrel to compress and convey food ingredients between the inner surface of the barrel, and a screw attached to an end of the cylinder barrel. An extruder for extruding food materials, characterized in that a gear-shaped stirring member having a diameter smaller than the mountain diameter of the screw is attached to the barrel insertion end of the screw. It is.

〔Effect of the invention〕

The present invention has the above-mentioned configuration, and the food raw materials that have been compressed between the barrel and the screw and conveyed while being mixed, kneaded, and melted are stirred by a gear-shaped stirring member attached to the tip of the screw. extruded from the die. Therefore, the desired extruded product can be obtained by causing a texturing reaction or the like in the food raw material before it travels from the tip of the screw to the die. Moreover, since the stirring member is constructed as described above, there is no fear that the product produced by the reaction will be destroyed.

〔Example〕

The present invention will be described below based on embodiments shown in the drawings.

What is shown in FIGS. 1 and 2 is an example of a two-screw type insertion machine.

Two screws 9 are inserted in parallel into the cylinder barrel 8. Barrel 8 for Skrill 9
Screw thread 9A that compresses and conveys food raw materials between
A reverse thread 9B is formed at the insertion end into the barrel 8 in a reverse thread. A stirring member 10 is attached to the tip of the screw 9, and has a structure in which three stages of semicircular gears 10A are formed, respectively. In addition, 7 is a hopper for supplying raw materials, 11 is an adapter for attaching the die 12 to the barrel 8, 1
3 is a cooling jacket, and 14 is a heater.

Now, the food raw materials put into the hopper 7 are mixed, kneaded, and melted by compressive force while being sent toward the tip of the barrel 8 by the rotation of the screw 9. Reverse thread 9 formed at the tip of screw 9
The raw material conveyed to B is further intensively kneaded with the raw material that is subsequently conveyed while being returned. The food ingredients that have passed through the reverse thread 9B are
While being stirred by the stirring member 10, the raw material undergoes appropriate stirring, mixing, and reaction while being naturally extruded from the die 12, thereby increasing the uniformity of the structure and toughness of the raw material.

Note that it is natural to change the stirring member depending on the pressure, residence time, and degree of stirring during extrusion depending on the nature of the food raw material, the shape of the extrudate to be obtained, etc., and the shape shown in Figs. 3 and 4 is Conceivable. The one in Figure 3 has a semicircular recess 10'A with a lead angle in the feed direction of the raw material, and the one in Figure 4 has a recess 10''A without a lead angle. It is something that

The inventor of the present invention has obtained defatted soybean flour (nitrogen solubility index NSI
We tested each stirring member in an extruder that processes meat protein using ≒35) as raw material, and all of them yielded better results than conventional ones. In particular, it has been confirmed that the one having the three-stage gear 10A shown in FIGS. 1 and 2 is optimal.

By the way, the axis distance Ds of Screw 9 is 45mm.
When the inner diameter Db of the barrel 8 was 55 mm, the gap CLt between the stirring members 10 was 1 mm.

[Brief explanation of drawings]

FIG. 1 is a diagram of an extruder showing an embodiment of the present invention;
Figure 2 is a cross-sectional view of Figure 1, Figures 3 and 4.
The figure shows an example of a stirring member, FIG. 5 shows a conventional extruder, and FIGS. 6 and 7 show examples of the tip of a screw. 8... Cylinder barrel, 9... Skrill, 9
A...screw thread, 10...stirring member.

Claims (1)

[Claims] 1. A cylinder barrel having a cylindrical shape, a screw having a thread and inserted into the barrel to compress and convey food ingredients between the inner surface of the barrel, and a die attached to an end of the cylinder barrel. 1. An extruder for extruding food materials, characterized in that a gear-shaped stirring member having a diameter smaller than the thread diameter of the screw is attached to the barrel insertion end of the screw.