JPH08112085A - Method for feeding and conveying food and apparatus therefor - Google Patents

Abstract

PURPOSE: To provide both a method for feeding and conveying a food at a low cost by which response to physical properties can be mad even when various changes are caused in the physical properties over a wide temperature range of about -20 to about +20 deg.C in a plastic oil and fat food, especially butter and preventing effects on contamination with microorganisms are manifested and an apparatus used therefor. CONSTITUTION: This method for feeding and conveying a food is to take in the food from an intake port of an apparatus for feeding and conveying comprising two-axle nearly complete meshing type screws 2 both having the cross sections in the axle direction of thread ridges comprising a trapezoidal shape and a barrel 4 surrounding the screws 2, rotate the screws in the mutual different directions, form a nearly hermetically sealed space between parts where the thread ridges and roots of the screws 2 are not directly meshed and the barrel 4 and quantitatively convey and discharge the food utilizing a conveying chamber formed in the space.

Description

Detailed Description of the Invention

[0001]

The present invention relates to the quantitative supply of foods.
The present invention relates to a transportation method and its apparatus. This feeding / transporting method and device is for feeding / transporting plastic oil and fat foods such as butter, margarine or spread, cheese (hereinafter referred to as plastic oil and fat food including cheese) and gel food without shearing or kneading. Is what you can do.

[0002]

2. Description of the Related Art When food is processed, it is taken out from a tank or a primary processing machine during the manufacturing process and then transferred to the next tank or a secondary processing machine. Is used. The devices used to supply and convey these foods are roughly classified into a pump type, a screw type, a compressed air type and a conveyor type. Supply again
The physical properties and shapes of the conveyed food products are various, and for example, they have plasticity properties, gel-like, highly viscous liquid-like, powdery, particle-like, lump-like and the like. The configuration of the equipment used for feeding / conveying these foods is adjusted so as to match the physical properties and form of the food and the feeding / conveying conditions, and there are various sizes and shapes. -The transport device has a mechanism in which relatively strong kneading and shearing are applied to food. Most foods are composites composed of various components, and the physical properties of the foods easily change depending on environmental conditions such as temperature, pressure, and humidity. Moreover, most of such changes are irreversible changes, and often result in deterioration of quality. Therefore, when relatively strong kneading or shearing is applied to such food in the supply / conveyance device, there is a problem that the quality deterioration is likely to occur due to temperature rise or tissue destruction.

Among the above-mentioned foods, butter is one of the foods that is apt to change depending on such feeding / conveying conditions. Its main components consist of 80% or more milk fat content and 18% or less water content, the solidification temperature of milk fat is about 10-35 ℃, and the solidification temperature of water is about 0 ℃, although it varies slightly depending on the salt content.
Is. Therefore, a differential scan calorimeter
ing calorimetry, DSC) etc., a clear phase transition is observed in these temperature zones. However, various rheological properties such as hardness and adhesiveness of butter, or viscosity, change continuously with temperature,
It usually does not have a clear transition point. For example, -20
The butter at ℃ is fairly hard and crushes with a strong impact, but it is -10
Butter at ℃ does not shatter even when shock is applied, but only deforms. That is, the temperature changes from solid to plastic. In this case, it is not clear at what temperature or less the crushing will start depending on how the shock is applied. When the temperature is further increased, the temperature gradually softens and at the same time the adhesiveness increases. This tendency continues up to around 10 ° C and gradually takes on physical properties as a fluid. When the temperature exceeds about 15 ° C, the structure becomes unstable, and scraps are easily formed when kneading, and when further kneading, the structure changes into a laminated state. In this way, the physical properties of butter vary greatly depending on the temperature, so handling is complicated, but what makes it more difficult to handle is that mechanical energy applied from the outside is easily converted into thermal energy, and this thermal energy It has the physical property of being plasticized by. That is, when supplying and transferring butter, the mechanical energy of the supply and transfer device driven by the power of the motor easily changes the temperature of the butter, and as a result, the physical properties of the butter change one after another as described above. There is a problem that it ends up.

Therefore, when supplying and transporting butter, a special constant volume type pump called a butter pump and a non-meshing type biaxial different direction rotating type screw such as an auger screw have been conventionally used. . Butter pumps are widely used as rotary pumps designed to take in a certain amount of butter and discharge it without kneading as much as possible, but it has pulsation and it is possible to widen the intake part structurally. It has the drawback of being difficult. Also,
The auger screw has a mechanism in which two relatively large non-meshing type screws are rotated in different directions to supply as little shear as possible, but this device can have a wide opening. On the other hand, it is difficult to increase the discharge force, and it is often used in combination with the above-mentioned butter pump. These butter pumps, auger screws, and other feeding / conveying devices are designed with the intention of supplying / conveying relatively soft butter at a temperature of approximately 5 ° C or higher, and are compatible with butter in the negative range of 0 ° C or lower. It is not a feeding / conveying device that can. In fact, the present inventors supplied and conveyed the butter in the negative region with a supply / conveying device such as a butter pump or an auger screw, but it was difficult to insert the butter pump due to the adhesion of butter at the inlet, and the auger. In the case of a screw, it was confirmed that butter adhered to the screw and was laminated, making operation difficult. In addition to butter, there are many foods such as margarine, cheese, or gel-like foods that easily change depending on the environment or operating conditions, and the same problems as in the case of butter occur in the supply and transportation thereof. To do.

[0005]

As described above, in the case of a device for supplying and conveying a plastic fat food such as butter,
Relatively soft butter of about 5 ° C. or higher must be supplied and transported under various constraint conditions, and quality deterioration is inevitable due to kneading and shearing. In addition, although foods have various physical properties, methods and devices for supplying and transporting foods have been developed that can cope with these physical properties, prevent deterioration due to kneading and shearing, and obtain high discharge force. Absent. Therefore, the present invention, plastic oil and fat food, especially in the supply and transportation of butter from about -20 ℃ to a wide temperature range of about 20 ℃ even if the physical properties are variously changed over a wide temperature range, and at low cost, It is an object of the present invention to provide a food supply / transport method and a device used therefor which are highly stable in preventing microbial contamination.

[0006]

The present invention adopts the following means in order to solve the above problems. That is, the axial cross section of the crest is formed in a trapezoidal shape, and the biaxial meshing type screw in which the mutual crests and troughs are almost completely meshed with each other, and from the food intake port of the feeding / conveying device consisting of the barrel surrounding the screw. Taking in food, rotating the screw in different directions to form a substantially sealed space between the valley and the barrel of the screw where the peaks and valleys do not directly mesh with each other, and quantitatively through that space It is a food supply / transport method characterized by transporting and discharging. Further, the device used for the method of supplying and conveying the above food is configured such that the axial cross section of the mountain has a trapezoidal shape, and a biaxial meshing type screw in which mutual ridges and valleys are almost completely meshed with each other,
A barrel that surrounds the screw, and the screws rotate in different directions, and a substantially sealed space is formed between the valley and the barrel of the screw where the peaks and valleys do not directly mesh with each other. A food supply / conveyance device characterized in that, in such a device, the pitch of the twin screw portion located at the food intake port is made wider than that of the conveyance unit to enhance the intake property of the food to be supplied. It is characterized by that.

[0007] When a conventional feeding / conveying device is used to feed / convey foods that are easily changed depending on temperature conditions, a problem is that the physical properties change due to heat generation of the food due to kneading or shearing in the device. In many cases. Therefore, in the present invention, a feeding / conveying method and a device were studied in which kneading and shearing in the feeding / conveying device were suppressed as much as possible and the temperature of the food was not raised. As a result, the axial cross-sectional shape of the crest is formed in a trapezoidal shape, and in a biaxial meshing type screw in which the mutual crests and troughs almost completely mesh with each other, the troughs of the screw portion where the crests and troughs do not directly mesh with each other. A space of constant volume is formed between the barrel and the barrel, and the method of supplying and conveying food in the space of constant volume is adopted. That is, when the biaxial screw is rotated in different directions, a surface in which the ridges and valleys of the screw do not directly mesh with each other and a substantially sealed space is formed between the barrels (hereinafter referred to as a transfer chamber). By taking in food from the food intake port, it became possible to convey food forward without changing the volume and shape of the conveying chamber. According to this supply / transport method, there is no kneading or shearing, so that the food does not generate heat, and there is an advantage that the physical properties of the food do not change. Further, in this supply / transport method, since the transport chamber has a high constant capacity, there is no pulsation, and the higher the driving force of the screw, the stronger the ejection force can be obtained. That is, according to the supply / transport method and apparatus of the present invention, it is possible to suppress the heat generation by suppressing the kneading and shearing that cause the deterioration of food quality as much as possible, and to obtain a high discharge force without pulsation. Is.

As the screw, a meshing type screw having a trapezoidal shape is used, but the volume of the transfer chamber can be increased as the trapezoidal shape is closer to a rectangle.
That is, since the transport amount can be increased and the edge of the screw crest is vertical, the uptake property can be further enhanced particularly when the screw food is used for feeding and transporting the lump food. Further, when such a rectangular screw is used, since the speed in the circumferential direction is greatly different in the transfer chamber due to the difference in the radius of gyration, slippage occurs, and the slippage does not easily cause the food to be bitten. And reduce shear.
Further, the smaller the gap between the screws or the screw and the barrel, the more closed the space can be formed. However, if it is too small, interference occurs between the screws or between the screw and the barrel. Therefore, it is preferable to set this gap as wide as possible within the allowable range of leakage according to the physical properties of the food.

The two screws are rotated in different directions from each other. When they are rotated in the same direction, the food products circulate around the two screws alternately, and between the two screws or between the screw and the barrel. This is because strong kneading and shearing are added. Further, in this case, the above-mentioned transfer chamber for accommodating the food cannot be formed. When two screws are installed side by side horizontally and rotated in different directions, the method of rotating inward from both sides in the direction of rotation (counterclockwise on the right side and clockwise on the left side in the transport direction, hereinafter referred to as inward) ), And both are rotated outwards (the right side in the transport direction is clockwise and the left side is counterclockwise or less, which is referred to as outer rotation). A transfer chamber for storing food is formed between the upper part of the screw and the barrel in the case of inner rotation, and between the lower part of the screw and the barrel in the case of outer rotation, so the rotation direction can be set according to the physical properties of the conveyed product. it can. For example, supply bulk food
It is supplied by feeding it from the food intake port of the carrier.
When the screw is set to the inner side during transportation, the ridges and valleys of the two screws alternately pass under the food, so that the food oscillates and the uptake property is enhanced. No such effect can be obtained on the outside. In addition, if the pitch of the biaxial screw located at the food intake port is made wider than that of the conveying section according to the physical properties and shape of the food, the food intake can be further enhanced. Furthermore, when deaerating food with a deaerator during transportation, it is preferable that there is no material to be conveyed above the screw to prevent venting up.Therefore, the screw is set to the outside and the conveying chamber that stores food below the screw. Should be formed.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments shown in the drawings will be described below.
1 and 2 show an overall view of a feeding / conveying device designed for feeding / conveying food. This feeding / conveying device mainly comprises a food intake port (1), two meshing type screws (2) arranged in a horizontal direction, and a drive unit (3) for rotating these two screws in mutually different directions. ), A barrel (4) surrounding the screw, a food conveying section (5) and a discharging section (6). A jacket (7) is installed on the barrel when temperature control is required during supply / transport. The food is introduced from the introduction port, taken in between the biaxial screws rotating in different directions, transferred by the transfer chamber formed by the screw and the barrel, and discharged from the discharge part at a constant flow rate. This supply / conveyance device can be applied to bulk foods, powder foods, particulate foods, viscous liquid foods, gel foods or plastic fat foods. In this configuration, the pitch of the screw located in the intake part is set wider than that of the transport part in order to enhance the intake property of the food intake part, but it is not necessary if the food to be supplied / transported has high fluidity. There is no.

FIG. 3 shows an example of a screw used in the present feeding / conveying device. All of them are trapezoidal almost perfect meshing type screws, and can be used according to the purpose. (A) is a case where the cross-sectional shape is rectangular,
The volume of the transfer chamber is maximized, and as described above, the action of taking in lumpy, powdery, particulate or plastic food at the charging port is strongest. In (b) and (c), the pressure fluctuation in the discharge part becomes smaller as the slope of the trapezoidal slope becomes gentler.
The kneading and shearing action of conveyed foods tend to be high. Note that (b) shows the screw when the slope of the trapezoidal slope becomes gentle, and (c) shows the screw when the slope of the trapezoidal slope becomes gentler.

As shown in FIG. 4, the transfer chamber includes a screw trough portion (A), a barrel portion (B), a screw crest portion (C), and a biaxial single-sided screw crest portion (D). ) (A), (B), (C), and (D).

Example 1 Using a crusher, the size is 350L x 315W x 200H (mm)
-20 ℃ frozen block butter is crushed to a particle size of about 0.1
A crushed butter was obtained having a temperature of about 30 mm and a temperature of about 0 ° C. When this crushing butter is rotated inward using the meshing trapezoidal screw according to the present invention shown in FIG. 3 (a), the crushed butter introduced is taken in without being retained at the charging port, and is also transferred to the transfer chamber. Due to the action of, it was conveyed without being subjected to kneading or shearing action. According to this conveyance, the butter was compressed and discharged as a continuous body, which was good without deterioration. In addition, in the feeding part, the oscillating action of the crushing butter peculiar to the inner circumference on the screw as described above was observed, which promoted the uptake property. With this method, the size is about 1 mm.
The following powdery pulverized butter was also contained in a large amount, but the incorporation, conveyance, and discharge were also good. Operating conditions in this method, the screw rotation speed 90 rpm, feed rate of butter is about 0.99 kg / hr, the discharge pressure of 6 kgf / cm ² on average was 12 kgf / cm ² at maximum. The temperature of the discharged butter was about 2 ° C., and when the amount of the crushed butter was constant, almost no pulsation of the discharged butter was observed. Example 2 Temperature is about −20 ° C. and size is about 50 L × 30 W × 20 H (mm)
The brick-shaped butter of No. 1 was used for the butter supply / conveyance device of the present invention of FIG. 1 in which the screw rotation speed was set to 90 rpm,
The uptake property, the transport property, and the ejection property were evaluated. As a result, there is no stagnation at the inlet and good uptake is achieved,
The transport and discharge were also good. The discharged butter was compressed into a continuous body, but the supplied brick-like butter was crushed and contained a large number of massive butters. The butter supply at this time was about 120 kg / Hr, and the discharge pressure was 8 k on average.
The gf / cm ² was 15 kgf / cm ² at the maximum, and the temperature of the discharged butter was about -17 ° C. In addition, Example 1
It was possible to supply quantitatively with almost no pulsation as in the case of. This method was also carried out on margarine and cheese frozen at about -20 ° C, and it was confirmed that the feedability and transportability were as good as those for butter.

EXAMPLE 3 In order to test the feedability of a highly viscous fluid food product, a soft atypical lumpy butter having a temperature of about 8 ° C. and a butter according to the present invention shown in FIG. It was supplied to the supply / transport device. As a result, the same good uptake as in Examples 1 and 2 was performed, and the transport and discharge were also good. The butter supply at this time is about 80 kg / hr.
In the discharge pressure is significantly lower than that since the occurrence of back pressure is small because the feed is soft in Examples 1 and 2, on average 3 kgf / cm ^2, was 5 kgf / cm ² at maximum, discharged The butter temperature was about 10 ° C. Also,
As in the case of Example 1, it was possible to quantitatively supply with almost no pulsation. As a highly viscous food, yogurt, melted cheese, jam, and the like were also subjected to a transportation test, and in each case, the transportation was possible without deteriorating the quality. Comparative Example 1 When the biaxial non-meshing type flat plate screw shown in FIG. 5 was attached to the feeding / conveying device and rotated inward and the same crushing butter as in Example 1 was charged, butter adhered to the intake part. It stayed and was kneaded and changed into a laminated state.
Once such a state occurs, the subsequent charging butter adheres to the staying butter and is kneaded one after another, so that discharge is impossible.

[0015]

The feeding / conveying method and apparatus of the present invention are
It can be applied to supply and transport of almost all foods such as lump foods, plastic oil and fat foods, highly viscous liquid foods, powdered foods and particulate foods. Since it does not generate heat due to kneading or shearing during supply and transportation, it is suitable for foods whose physical properties are likely to change when kneading or shearing is added. In addition, a great effect can be obtained when it is desired to enhance the uptake property or when a strong ejection force is required. Further, not only can it be supplied and transported at a low cost, but since it is transported in a sealed state, it has the effect of preventing contamination of microorganisms.

[Brief description of drawings]

FIG. 1 is an overall front sectional view of a food supply / conveyance device of the present invention.

FIG. 2 is a plan view of a food supply / conveyance device of the present invention.

3A, 3B and 3C are explanatory views of a screw used in the feeding / conveying device of the present invention.

FIG. 4 is an explanatory diagram of a transfer chamber.

FIG. 5 is an explanatory diagram of a conventional auger screw.

[Explanation of symbols]

 1 Intake port 2 Screw 3 Drive part 4 Barrel 5 Conveying part 6 Discharging part 7 Temperature control jacket

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display B65G 33/26

Claims (3)

[Claims] 1. A supply comprising a biaxial meshing type screw having a trapezoidal axial cross-section, in which the mutual peaks and valleys are almost completely meshed with each other, and a barrel surrounding the screw.
Food is taken in from the food intake port of the conveyor, and the screws are rotated in different directions to form a nearly sealed space between the valley and the barrel of the screw where the peaks and valleys do not directly mesh with each other. A method of supplying / transporting food, characterized in that it is quantitatively transported through the space and then discharged. 2. A biaxial intermeshing screw having a trapezoidal axial cross-section, in which the ridges and valleys are almost completely meshed with each other, and a barrel surrounding the screw, and the screws are different from each other. A food supply / conveyance device characterized in that a substantially sealed space is formed between a barrel and a barrel of a screw portion that rotates in a direction and mutual peaks and troughs do not directly mesh with each other. 3. The food supply according to claim 2, wherein the pitch of the twin screw portion located at the food intake is made wider than that of the conveying section to enhance the intake of the food to be supplied. Transport device.