IE950974A1 - A method and apparatus for manufacturing intermediate¹products for preparation of foods. - Google Patents

Abstract

Raw granular materials are delivered from selected storage bins (17) to a toaster feed hopper (41). The raw granular materials are fed in a controlled manner from the toaster feed hopper (17) through an associated toaster (35). In passing through the toaster (35), the materials are conditioned by heating. Downstream of the toaster (35), the materials are cooled to form the intermediate products for preparation of animal feeds. <Fig. 1>

Description

This invention relates to a method and apparatus for manufacturing intermediate products for the preparation of foods, in particular animal feed and the like.

The invention particularly relates to the conditioning of raw granular materials such as maize, wheat, barley, soya, peas and the like for subsequent use in the production of foods such as animal feeds. The conditioning may include inactivating undesirable toxins, sterilising and/or gelatising the raw granular materials. It is an object of the invention to provide a method for efficiently conditioning raw granular materials to produce high quality intermediate food grade products which may be used for the preparation of animal feeds and the like.

According to the invention, there is provided a method for manufacturing intermediate products for preparation of foods, comprising the steps :delivering a raw granular material to a storage bin, conveying the raw granular material from the storage bin to a toaster feed hopper, discharging raw granular material from an outlet of the toaster feed hopper at a desired feed rate, delivering the raw granular material from the toaster feed hopper outlet through a toaster, controlling the rate of delivery of raw granular material through the toaster by maintaining a desired quantity of raw material in the toaster feed hopper - 2 to supply the toaster on demand with the desired feed rate of raw granular material, the desired quantity of raw granular material being maintained in the toaster feed hopper by sensing the level of raw granular material in the feed hopper and controlling the flow of raw granular material from the storage bin to the toaster feed hopper in response to said sensed raw granular material level in the toaster feed hopper, heating the raw granular material in the toaster to condition the raw granular material, discharging conditioned granular material from the toaster, and cooling the conditioned granular material.

In another embodiment, the method includes maintaining a desired quantity of raw granular material in the feed hopper by delivering raw granular material from the storage bin to the feed hopper by means of a filling conveyor, sensing a low level of material in the feed hopper associated with a minimum desired quantity of raw granular material in the feed hopper, sensing a high level of material in the feed hopper associated with a maximum desired quantity of raw granular material in the feed hopper, and controlling operation of the filling conveyor in response to the sensed raw granular material level for maintaining the amount of raw granular material in the feed hopper between the minimum and maximum desired values to provide the desired feed rate of raw granular material to the toaster. - 3 Preferably, the method includes discharging the raw granular material from the feed hopper by means of a screw conveyor extending between an outlet of the feed hopper and an inlet of the toaster, the screw conveyor having a material conveying screw rotatably mounted within an associated housing, the screw being driven by a variable speed motor, the motor being operable for delivery of the raw granular material from the feed hopper to the toaster at the desired feed rate.

In a further embodiment, the method includes controlling the moisture content of the raw granular material delivered to the toaster to a pre-desired value by adding water to the raw granular material upstream of the toaster feed hopper, mixing the water with the raw granular material and holding the raw granular material for a preset time period for absorbtion of the water by the raw granular material prior to delivery to the toaster.

Preferably, the method includes discharging raw granular material from the storage bin, conveying the raw granular material through a water sprayer, spraying water onto the raw granular material in the water sprayer, mixing the raw granular material for evenly distributing the water throughout the raw granular material, and delivering the wetted raw granular material to a storage bin upstream of the toaster feed hopper.

In another embodiment, the method includes delivering the raw granular material through the water sprayer in a number of passes for incrementally raising the water content of the raw granular material to a preset desired value. - 4 In a preferred embodiment, the method includes adding water to the raw granular material prior to delivering the raw granular material to the storage bin.

In a further embodiment, the method includes adding water to the raw granular material by passing the raw granular material through a trough, injecting a desired amount of water onto the raw granular material as it is moving through the trough, mixing the water with the raw granular material and advancing the raw granular material through the trough by means of a plurality of helically arranged paddles mounted on a rotatable shaft within the trough for vigorously mixing the material as it is moving through the trough between an inlet and an outlet of the trough.

Preferably, the method includes rolling the granular material downstream of the toaster.

Most preferably, the method includes passing the conditioned granular material between a pair of rollers for further processing the conditioned granular material prior to cooling and adjusting the relative spacing between the rollers while running the rollers and passing conditioned granular material therebetween for controlling the flattening of the conditioned granular material by the rollers .

In a further embodiment, the method includes feeding conditioned granular material to the rollers by delivering conditioned granular material to a supply hopper above the rollers, gravity feeding the conditioned granular material from an outlet at a bottom of the supply hopper to a vibrator, discharging the conditioned granular material from the vibrator between the rollers, controlling the vibrator for regulating the rate of delivery of - 5 conditioned granular material from the outlet of the supply hopper to the rollers.

Preferably, the method includes delivering conditioned granular material from the toaster to a holding bin and controlling discharge of material from an outlet of the holding bin for delivery to the cooler and retaining the conditioned granular material in the holding bin for a preselected dwell time.

In another aspect the invention provides a method for manufacturing an animal feed comprising the step:delivering ingredient materials to a plurality of storage silos, discharging preset amounts of selected ingredient materials from chosen storage silos to a weigher, weighing measured amounts of the selected ingredient materials in a preset desired ratio, discharging the weighed batch of ingredient materials to a holding bin, forming a charge of selected additive material associated with the batch of ingredient materials, collecting the additives in a charge hopper, combining the charge of additive materials with the batch of ingredient materials, discharging the batch of ingredient materials and additive materials from the holding bin to a mixer, - 6 mixing the materials in the mixer for a preset time period to from an homogenous feed mix, delivering the feed mix from the mixer to a collecting bin, discharging the feed mix from the collecting bin by means of a screw conveyor, adding liquid molasses to the feed mix as it is being delivered to the screw conveyor and mixing the molasses with the feed mix for coating the materials of the feed mix with molasses as the feed mix moves between an inlet and an outlet of the screw conveyor for forming an animal feed which is discharged from the outlet of the screw conveyor.

In a preferred embodiment of the invention the ingredient materials include intermediate products as previously described.

In a further embodiment of the invention the method includes adding the molasses to the feed mix adjacent an inlet of the screw conveyor for through passage of the batch of feed mix and the molasses in the screw conveyor for evenly distributing a preset desired amount of molasses throughout the batch of feed mix, coating the materials of the feed mix with molasses.

The invention will be more clearly understood by the following description of some embodiments thereof, given by way of example only, with reference to the accompanying drawings, in which:Fig. 1 is a schematic diagram illustrating a method and apparatus for carrying out the invention; - 7 Fig. 2 is a diagrammatic sectional elevational view of a spraying apparatus used in the method; Fig. 3 is a detail partially sectioned end elevational view of a mixing paddle of the spraying apparatus; Fig. 4 is a detail schematic illustration of a toasting station forming portion of the apparatus; Fig. 5 is a detail schematic illustration of a rolling station forming portion of the apparatus; and Fig. 6 is a schematic diagram illustrating a method and apparatus for manufacturing animal feed according to the invention.

Referring to the drawings and initially to Figs. 1 to 5 thereof, a method and apparatus for manufacturing intermediate products for the preparation of foods according to the invention will be described.

Granular material such as barley, maize, peas, soya beans and the like, delivered to an intake 10 is conveyed to a holding bin 11. From the holding bin 11, the granular material is fed through a vibrating sieve 12 which removes foreign matter, the granular material passing through the sieve 12 to an elevator 14. Granular material discharged from an outlet 15 of the elevator 14 is delivered by a screw conveyor 16 to one of a number of storage bins 17. A water sprayer 18 is mounted between the outlet end 15 of the elevator 14 and the storage bins 17 and the granular material may optionally be delivered through the sprayer 18 prior to discharge into the storage bins 17. - 8 The sprayer 18 comprises a trough within which a ribbon screw is rotatably mounted for carrying material through the trough. Overhead spray nozzles are operable to inject water onto the granular material as it is delivered through the trough, the ribbon screw mixing the water through the granular material.

It will be noted that an outlet of each storage bin 17 is connected through a stop valve with a recirculating conveyor 20 for delivery of granular material from a storage bin 17 to an inlet of the elevator 14 for recirculation of material from a storage bin 17 through the water sprayer 18 and back to the storage bin 17. In this way, granular material such as barley, may be circulated through the sprayer 18 in a number of passes to incrementally increase the water content of the granular material to a preset desired value. The moistened raw granular material is held in the storage bin 17 for a preset time period before use to allow even absorbtion of water throughout the raw granular material.

In some cases, it is necessary to add water to the raw granular material prior to delivery to the storage bins 17 due to the expansion of the granular material when water is added. In this case, the water is added and the raw granular material is allowed swell in a holding bay prior to delivery of the raw granular material to the intake 10.

Suitable apparatus for wetting the raw granular material is shown in Figs. 2 and 3. The apparatus comprises an intake hopper 22 for feeding granular material into a trough 23 containing a paddle mixer 24 rotatable within the trough 23 by means of an adjustable speed drive motor 25 for delivery of granular material between an inlet 26 and an outlet 27 of the trough 23. A spray bar 28 95θ974 - 9 supplies water to a number of nozzles 29 at a top of the trough 23 for spraying water onto granular material as it is delivered through the trough 23. Preferably, the trough 23 is inclined upwardly between the inlet 26 and outlet 27 as shown in Fig. 2. Referring to Fig. 3, the paddle mixer 24 comprises a rotatable shaft 30 on which are arranged a plurality of paddles 31 arranged in a generally helical array on the shaft 30. It will be noted that adjacent paddles 31 are offset at an angle to each other and this advantageously ensures good mixing and agitation of the granular material as it is progressed by the paddles 31 between the inlet 26 and outlet 27 of the trough 23. Each paddle 31 is fixed on the shaft 30 by a mounting bolt 32 attached at an inner end of the paddle 31 which passes through the shaft 30 to which it is secured by means of a nut 33.

In use, the speed of the drive motor 25 is set appropriate to the nature of the raw granular material passing through the trough. It has been found that advantageously the inclined trough configuration gives improved control of water addition. This method of water addition advantageously promotes an even water absorbtion through the particles. Also advantageously, the subsequent handling of the raw granular material is easier.

It will be appreciated that the lay up times allowed after wetting and prior to delivery of the raw granular material to the storage bins will vary with different granular materials such as maize, wheat and barley for example. The lay up time will depend on the nature of the material and the quantity of moisture being added to the material.

Granular material is delivered from a selected storage bin by delivery means 34 to a toaster 35. The toaster 35 has a rotating drum 36 through which the granular material - 10 is delivered. A furnace 37 at an inlet end of the drum 36 generates hot gases which are passed through the drum 36 with the raw granular material for heating the raw granular material to condition the raw granular material.

Referring to Fig. 4, the operation of the toaster is optimised by controlling the flow of raw granular material through the toaster 35. The delivery means 34 has a supply conveyor 40 operable to deliver raw granular material from a selected storage bin 17 to a toaster feed hopper 41. A high level sensor 42 and a low level sensor 43 in the toaster feed hopper 41 are connected to a controller for a motor driving the conveyor 40, the motor switching on when the low level sensor 43 is uncovered and switching off when the high level sensor 42 is covered. A screw feeder 45 extends between an outlet of the feed hopper 41 and an inlet 46 of the drum 36. The screw feeder 45 has a material conveying screw 47 driven by a variable speed motor 48 for controlling the rate of delivery of material from the feed hopper 41 to the drum 36 appropriately for the type of raw granular material being delivered through the toaster 35.

The raw granular material is delivered through the toaster 35, the temperature within the toaster 35 being controlled to condition the raw granular material as required.

Generally, an initial quantity of the raw granular material passed through the toaster 35 will not be correctly conditioned and material discharged from the toaster 35 can be recirculated back to the feed hopper 41 for passage through the toaster 35 a second time for proper conditioning of the material.

Conditioned granular material discharged from the toaster 35 is delivered to a screw conveyor 50 having a first •E 950974 - 11 outlet 51 which feeds directly to a cooler 52 and additional outlets which lead to either a first rolling station 54 or a second rolling station 55. At the first rolling station 54, material passes between a pair of plain rollers 56. At the second rolling station 55, material is passed between a pair of fluted rollers 58. One of the rollers 58 is fixed and the other roller 58 is slidably movable towards and away from the fixed roller 58. In this way, advantageously, it is possible to adjust the relative spacing of the rollers 58 while running the rollers 58 and passing conditioned granular material therebetween for controlling the flattening of the conditioned granular material by the rollers 58.

Feed of conditioned granular material through the rollers 56, 58 is controlled by delivering the conditioned granular material from the feed screw 50 into a supply hopper 60, 61 mounted above each pair of rollers 56, 58. Each supply hopper 60, 61 has a low level sensor 62, 63 and a high level sensor 64, 65. Conditioned granular material is gravity fed from an outlet 66, 67 at a bottom of the supply hopper 60, 61 to a vibrator 68, 69 which feeds the material evenly between the associated pair of rollers 56, 58. The shaking of the vibrator 68 is controlled for regulating the rate of delivery of conditioned granular material from the outlet 66, 67 of the supply hopper 60, 61 to the rollers 56, 58. The vibrator 68, 69 and the probes 62, 63, 64, 65 are connected to a controller. The vibrator 68 is run at a set speed selected appropriate to the material being processed. When conditioned granular material fills the supply hopper 60, 61 and reaches the high level probe 64, 65, the speed of the vibrator 68, 69 is increased by between 5-25% (depending on the percentage speed increase selected) thus lowering the level in the supply hopper 60, 61. Should the level within the supply hopper 60, 61 - 12 reach the low level probe 62, 63, the vibrator is switched back by the controller to its normal running speed.

Rolled material is delivered from an outlet 70, 71 of the rollers to the cooler 52. Downstream of the cooler 52, the cooled conditioned granular material is delivered to a holding bin 75. The conditioned granular material may be delivered from the holding bin 75 for use or further processing.

The material delivered from the screw conveyor 50 to the first outlet 51 may be delivered to a holding bin 59 (Fig. 1) and discharge of material from the holding bin 59 controlled for retaining the material in the holding bin 59 for a preselected dwell time prior to delivery to the cooler 52.

Upstream of the intake 10, raw granular material may be initially prepared by passing the raw granular material through a beater and then through a cleaner to remove impurities. A filter associated with the cleaner removes fine dust from the raw granular material which advantageously prevents fouling of machinery downstream of the cleaner and prevents escape of the dust into the atmosphere thus providing an improved working environment.

It will be appreciated that the invention provides a method for manufacturing high quality intermediate products for the preparation of foods, in particular animal feed and the like. It is envisaged that the method may also be applied to the preparation of intermediate products for foods intended for human consumption.

Referring now to Fig. 6, a method for manufacturing animal feed according to the invention will be described.

Ingredient materials are delivered to a plurality of - 13 storage silos 80. The storage silos 80 each contain materials such as wheat, barley, oats and the like, some of which may have already been conditioned in the toaster as previously described.

To produce a particular animal feed, preset amounts of selected ingredient materials are discharged from chosen storage silos 80 into a weigher 81. Measured amounts of the selected ingredient materials in a preset desired ratio are collected in the weigher 81.

The weighed batch of ingredient materials is then discharged from the weigher 81 into a holding bin 82.

A charge of selected additive materials, such as minerals and vitamins, are weighed out in desired portions relative to the batch of ingredient materials and collected in a charge hopper 83. The additive materials are then discharged from the charge hopper 83 into the holding bin 82 for combination with the batch ingredient materials in the holding bin 82.

Next, the batch of ingredient materials and additive materials are discharged from the holding bin 82 into a mixer 85. Within the mixer 85 the materials are mixed for a preset time period to form an homogenous feed mix.

When mixing has been completed the feed mix is delivered into a collecting bin 86 and an outlet of the mixer 85 is closed to prepare the mixer 85 for reception of a fresh batch of ingredient materials from the holding bin 82, said fresh batch having been prepared while the mixing of the first batch was taking place in the mixer 85.

The feed mix is discharged in a controlled manner from the collecting bin 86 by means of a screw conveyor 88. The Έ 950974 - 14 screw conveyor 88 has a trough 89 within which is rotatably mounted a screw 90 driven by an external motor 91 for advancing material between an inlet 92 and an outlet 93 of the screw conveyor 88. Liquid molasses is added into the feed mix as it drops from the collecting bin into an inlet of the screw conveyor 89. The liquid molasses is delivered at a desired pressure by a pump 97 from a molasses supply tank 98. By controlling the pressure of the molasses spray and the rate of delivery of the feed mix through the screw conveyor 89 advantageously the molasses is evenly distributed throughout the batch of feed mix discharged from the collecting bin 86 to form a high quality homogenous animal feed which is discharged from the outlet 93. The animal feed may be collected from the outlet 93 for transport in bulk or maybe bagged prior to transport.

It will be noted that the controlled mixing of the molasses with the feed mix gives a high quality animal feed binding the ingredient materials and thus preventing or at least minimising separation of the ingredient materials within the feed. The molasses also gives the animal feed a distinct aroma and flavouring which makes the feed attractive to animals. A further advantage of the manner in which the molasses is added is that it acts as a dust suppressant promoting a more comfortable working environment.

The invention is not limited to the embodiments hereinbefore described which may be varied in construction and detail.

Claims (19)

1. A method for manufacturing intermediate products for preparation of foods, comprising the steps :delivering a raw granular material to a storage bin, conveying the raw granular material from the storage bin to a toaster feed hopper, discharging raw granular material from an outlet of the toaster feed hopper at a desired feed rate, delivering the raw granular material from the toaster feed hopper outlet through a toaster, controlling the rate of delivery of raw granular material through the toaster by maintaining a desired quantity of raw material in the toaster feed hopper to supply the toaster on demand with the desired feed rate of raw granular material, the desired quantity of raw granular material being maintained in the toaster feed hopper by sensing the level of raw granular material in the toaster feed hopper and controlling the flow of raw granular material from the storage bin to the toaster feed hopper in response to said sensed raw granular material level in the toaster feed hopper, heating the raw granular material in the toaster to condition the raw granular material, - 16 discharging conditioned granular material from the toaster, and cooling the conditioned granular material.

2. A method as claimed in claim 1 which includes maintaining a desired quantity of raw granular material in the feed hopper by delivering raw granular material from the storage bin to the feed hopper by means of a filling conveyor, sensing a low level of material in the feed hopper associated with a minimum desired quantity of raw granular material in the feed hopper, sensing a high level of material in the feed hopper associated with a maximum desired quantity of raw granular material in the feed hopper, and controlling operation of the filling conveyor in response to the sensed raw granular material level for maintaining the amount of raw granular material in the feed hopper between the minimum and maximum desired values to provide the desired feed rate of raw granular material to the toaster.

3. A method as claimed in claim 1 or 2 which includes discharging the raw granular material from the feed hopper by means of a screw conveyor extending between an outlet of the feed hopper and an inlet of the toaster, the screw conveyor having a material conveying screw rotatably mounted within an associated housing, the screw being driven by a variable speed motor, the motor being operable for delivery of the raw granular material from the feed hopper to the toaster at the desired feed rate.

4. A method as claimed in any preceding claim which includes controlling the moisture content of the raw granular material delivered to the toaster to a preIE 950974 - 17 desired value by adding water to the raw granular material upstream of the toaster feed hopper, mixing the water with the raw granular material and holding the raw granular material for a preset time period for absorbtion of the water by the raw granular material prior to delivery to the toaster.

5. A method as claimed in claim 4 which includes discharging raw granular material from the storage bin, conveying the raw granular material through a water sprayer, spraying water onto the raw granular material in the water sprayer, mixing the raw granular material for evenly distributing the water throughout the raw granular material, and delivering the wetted raw granular material to a storage bin upstream of the toaster feed hopper.

6. A method as claimed in claim 5 which includes delivering the raw granular material through the water sprayer in a number of passes for incrementally raising the water content of the raw granular material to a preset desired value.

7. A method as claimed in any of claims 1 to 4 which includes adding water to the raw granular material prior to delivering the raw granular material to the storage bin.

8. A method as claimed in claim 7 which includes adding water to the raw granular material by passing the raw granular material through a trough, injecting a desired amount of water onto the raw granular material as it is moving through the trough, mixing the water with the raw granular material and advancing the raw granular material through the trough by means of a plurality of helically arranged - 18 paddles mounted on a rotatable shaft within the trough for vigorously mixing the material as it is moving through the trough between an inlet and an outlet of the trough.

9. A method as claimed in any preceding claim which includes rolling the granular material downstream of the toaster.

10. A method as claimed in claim 9 which includes passing the conditioned granular material between a pair of rollers for further processing the conditioned granular material prior to cooling and adjusting the relative spacing between the rollers while running the rollers and passing conditioned granular material therebetween for controlling the flattening of the conditioned granular material by the rollers.

11. A method as claimed in claim 9 or 10 which includes feeding conditioned granular material to the rollers by delivering conditioned granular material to a supply hopper above the rollers, gravity feeding the conditioned granular material from an outlet at a bottom of the supply hopper to a vibrator, discharging the conditioned granular material from the vibrator between the rollers, controlling the vibrator for regulating the rate of delivery of conditioned granular material from the outlet of the supply hopper to the rollers.

12. A method as claimed in any of claims 1 to 8 which includes delivering conditioned granular material from the toaster to a holding bin and controlling discharge of material from an outlet of the holding bin for delivery to the cooler and retaining the - 19 conditioned granular material in the holding bin for a preselected dwell time.

13. A method for manufacturing intermediate products for preparation of foods substantially as hereinbefore described with reference to the accompanying drawings .

14. Intermediate products for the preparation of foods whenever manufactured by the method as claimed in any preceding claim.

15. Animal feed including intermediate products as claimed in claim 14.

16. A method for manufacturing an animal feed incorporating intermediate products as claimed in claim 14 comprising the steps: delivering ingredient materials including the intermediate products to a plurality of storage silos, discharging preset amounts of selected ingredient materials from chosen storage silos to a weigher, weighing measured amounts of the selected ingredient materials in a present desired ratio, discharging the weighed batch of ingredient materials to a holding bin, forming a charge of selected additive materials associated with the batch of ingredient materials, 9 S097 4 collecting the additive materials in a charge hopper, combining the charge of additive materials with the batch of ingredient materials, discharging the batch of ingredient materials and additive materials from the holding bin to a mixer, mixing the materials in the mixer for a preset time period to form an homogenous feed mix, delivering the feed mix from the mixer to a collecting bin, discharging the feed mix in a controlled manner from the collecting bin by means of a screw conveyor, adding liquid molasses to the feed mix as it is being delivered to the screw conveyor and mixing the molasses with the feed mix for coating the materials of the feed mix with molasses as the feed mix moves between an inlet and an outlet of the screw conveyor for forming an animal feed which is discharged from the outlet of the screw conveyor.

17. A method as claimed in claim 16 which includes adding the molasses to the feed mix adjacent an inlet of the screw conveyor for through passage of the batch of feed mix and the molasses in the screw conveyor for evenly distributing a preset desired amount of - 21 molasses through the batch of feed mix, coating the materials of the feed mix with molasses.

18.

19. A method for manufacturing animal feed substantially as hereinbefore described as reference to the accompanying drawings . Animal feed whenever manufactured according to the method as claimed in any of claims 16 to 18.