GB2240493A - Electrostatic flavouring apparatus - Google Patents

Abstract

An applicator for applying powdered flavouring to foodstuffs includes a fluidised bed for providing a supply of powdered flavouring, a particle accelerator and an electrostatic charging head (1) arranged to disperse an airborne flow of powdered flavouring within a body of foodstuffs. <IMAGE>

Description

FLAVOURING APPARATUS This invention relates to apparatus for application of flavouring compounds for foodstuffs, particularly but not exclusively to snack foods such as biscuits, corn chips, crisps, breakfast cereals and other products in the form of discrete pieces.

Flavouring compounds are ,usually provided in an extremely concentrated form and require homogeneous dilute application to avoid adverse consumer reaction.

Concentrated flavourings are usually very intense and even occasional agglomerations within a food product can result in complaint. Conventional foodstuff manufacturing operations have involved application of powdered flavouring using a screw conveyor or vibrating doctor, blade or aperture. Such arrangements do not achieve homogeneous distribution of the flavouring. It is often necessary to dilute the flavouring with a carrier such as flour to reduce the incidence of agglomerations. Adherence of the powdered flour to the foodstuff, especially corn products such as tortilla chips, is often poor. The powdered flavouring, especially when diluted with an inert carrier is often dispersed in oil to enhance adhesion to the foodstuff. This has several disadvantages. In addition to the cost of the oil, agglomerations of flavoured oil are common.Furthermore deposits of oil may build up in the apparatus, making regular cleaning and maintenance a necessity. Uniform distribution of the oily mixture throughout the foodstuff is difficult to achieve. Moreover the oils add unnecessarily to the calorific value of the product.

According to the present invention a foodstuffs flavouring applicator includes means for providing an airborne flow of powdered flavouring said means including at least one outlet arranged to be disposed in use in the proximity of a quantity of said foodstuff, an electrostatic charging head disposed adjacent said outlet and arranged in use to induce an electrostatic charge in the flow of said flavouring.

Although air may be generally used for propelling the powdered flavouring, nitrogen, carbon dioxide or mixtures of these and other gases may be used as convenient.

Use of the apparatus in accordance with this invention confers several advantages. Concentrated flavourings may be employed with a significantly decreased occurence of agglomerations. Adherence of the flavouring to the foodstuff is considerably enhanced due to electrostatic attraction. Less of the flavouring need be employed, affording a considerable saving in material costs. Savings of 356 are commonplace and savings of up to 70% have been observed. In addition the line speed of the production apparatus may be increased. The increased adherence of the flavouring to the product enhances the shelf time of the latter. The necessity for dilution of the flavouring with an inert carrier or use of an oil are both obviated.

Preferred apparatus in accordance with this invention incorporates a plurality of outlets adjacent the or each charging head.

The charging head may comprise an electrode disposed in equidistant spaced relation to a plurality outlets. The charging head may be located at the end of an elongate support or probe, the latter being adapted to be inserted into a body of foodstuff agitated within a container, for example a rotary mixing drum.

The means for providing an airborne flow of powdered flavouring may comprise a fluidised bed arranged to provide a supply of powdered flavouring suspended in the flow of air. The fluidised bed may be agitated in use.

A powder accelerator manufactured in accordance with the disclosure of UK Patents 1498424 or 1333091 may be provided at the outlet from the fluidised bed. The powder accelerator comprises an inlet for an airborne flow of powdered flavouring , and a second inlet for incorporating compressed air into the flow to accelerate the latter.

According to a preferred aspect of the present invention, the applicator includes a receptacle for storing powdered flavouring and a powder accelerator disposed between the receptacle and the outlet, the powder accelerator comprising an inlet for an airborne flow of powdered flavouring from the receptacle and a second inlet for supply of compressed gas, the second inlet surrounding the first inlet and being arranged so that gas flow from the second inlet causes acceleration of the particle flow from the first inlet.

The powder accelerator may further include a third inlet for supply of compressed gas, the third inlet surrounding the second inlet and being arranged so that gas flow from the third inlet causes further acceleration of the particle flow from the second inlet.

Provision of two inlets for compressed gas allows the rate of delivery of powdered flavouring to be controlled over a wide range. This serves to accomodate variations in application rates, for example in the event that the production rate is to be increased. Flavouring materials having different particle sizes and densities may also be efficiently applied.

The invention is further described by means of example but not in any limitative sense with reference to the accompanying drawings of which: Figure 1 is a cross-sectional view of a charging head in accordance with this invention; Figure 2 illustrates the receptacle for powdered flavouring; Figure 3 illustrates use of the charging head; Figure 4 illustrates an alternative receptacle for powdered flavouring; Figure 4 illustrates a plan view of the baffle of the receptacle shown in Figure 2; Figure 6 illustrates a velocity reducer for use in apparatus in accordance with this invention; Figure 7 illustrates an exploded view of the components of the reducer shown in Figure 6; and Figure 8 illustrates a powder accelerator in accordance with this invention.

Like reference numerals are used in each Figure to denote like parts.

Electrostatic charging arrangement shown in Figure 1 comprises a rod-like electrode 1 having insulation 2 connected to an HT supply 7. Two tubes 3 are disposed equidistantly adjacent the end the electrode so that an airborne flow of powder 6 passing from the outlet 4 of the tubes 3 is charged by induction. Conical deflectors 5 disposed downstream from the outlets 4 further distribute the particulate flow 6. Alternative deflectors may be pyramidal or differently shaped.

The supply for flavouring is shown in Figure 2 and comprises a receptacle forming a fluidised bed 10 having an inlet for compressed air 11 and a vibrator 12. A sieve 13 may be disposed above the upper opening of the fluidised bed to break up any aggregations of the flavouring material and to remove any foreign bodies. The outlet 15 to the charging head located near the bottom of the receptacle is connected to the fluidised bed via a particle accelerator 14 to which compressed air 17 is delivered to accelerate the particle stream.

A plurality of aperture plates 16 extends across the width of the receptacle between the opening inlet 13 and the outlet 15. The plates may be supported upon an axial rod 17. Apertures in the baffles as shown in Figure 5 may be arranged so that the apertures 20 of adjacent baffles 16 are non-coincident, preventing powdered flavouring from falling directly through them. The baffles may be arranged to extend horizontally or may be inclined to enhance homogenisation of the powdered material.

Figure 3 illustrates use of the charging head as shown in Figure 1 disposed parallel to the axis of a cylindrical rotating drum or otherwise as convenient. Tortilla chips or other foodstuff is agitated within the drum and maintained generally at earth potential by contact with it.

The powdered foodstuff, charged by induction from the electrode 1 adheres strongly to the foodstuff and coats all surfaces of it. Moreover electrostatic repulsion between the particles of flavouring material reduces the formation of agglomerations.

Figure 4 illustrates an alternative receptacle having a helical lifting screw 30 supported upon a shaft 31 and arranged to be driven in use by a motor 32. Powdered material within the receptacle 33 coming into contact with the screw 30 is raised within the receptacle 33 causing mixing and maintaining a homogenous fluidised bed.

Figures 6 and 7 illustrate a velocity reducer for reducing the rate of powder flow immediately prior to entering the charging head. A supply of powdered material entrained in an air flow from the receptacle (not shown) passes via pipe 43 to a tubular feed insert 42. A connector 41 having a bore 45 through which the powdered material can pass is arranged to receive the insert 42 into the end of a barrel 40. The outlet 45 of the connector extends downstream of apertures 46 in the barrel 40. The apertures allow air to enter at atmospheric pressure into the barrel behind the exit of the connector 45. The apertures 46 are equidistantly spaced around the diameter of the barrel 40 to provide an even air flow. Aperture of a larger size may be located upstream of smaller sized apertures to compensate for the reduced suction on them in use.The velocity reducer may be fitted to the inlet to the charging head, reducing the velocity of the powder supplied to the head by the powder accelerator as described below. The barrel 40 may be integral with the tubes 3 shown in Figure 1. Alternatively the velocity reducer may be provided upstream of the charging head for example in the hose to which it is connected. Reduction in the powder velocity enhances the electrostatic charge applied to it, avoiding the need for a low velocity in the hose or other conduit from the fluidised bed receptacle.

Figure 8 is a cross-sectional view of a powder accelerator which may be used connected to the wall 50 of the receptacle or alternatively may be disposed separately within a line from the receptacle to the electrostatic powder applicator. Location adjacent the receptacle is preferred to facilitate transmission of the airborne powder from the receptacle to the applicator. An inlet 51 includes a cylindrical bore 54 having an outlet 55 from which an airborne flow of powdered flavouring passes from the fluidised bed. A supply of compressed air is delivered via inlet 52 to an annular chamber 59. A tubular bore 61 having a diameter slightly greater than the exterior diameter of the inlet 54 defines a cylindrical second inlet 58 surrounding the primary inlet 55.

Compressed air delivered through the connector 52 acceleratres the powder flow emerging from the opening 55.

A second inlet 53 for compressed air communicates with a respective cylindrical annular ball 57 surrounding the outlet 56 from which the accelerated flow emerges.

Application of compressed air to the third outlet 57 further accelerates the powder flow ensuring efficient transmission to the electrostatic charging head and distribution upon the food product. The supplies of compressed air to the connectors 52 53 may be altered as desired in accordance with particular requirements, including the distance of the accelerator from the electrostatic head, the size and rate of delivery of powdered material and other factors.

The powder accelerator of this invention may be used independently of the fluidised bed and or electrostatic charging head for application of flavourings to foodstuffs.

It will be obvious to those having ordinary skill in the art that many changes can be made in the above described preferred embodiments of the present invention.

Therefore the scope of the present invention should be determined by the following claims.

Claims (9)

1. A foodstuffs flavouring applicator including means for providing an airborne flow of powdered flavouring, said means including at least one outlet arranged to be disposed in use in proximity to a quantity of said foodstuffs, an electrostatic charging head disposed adjacent to said outlet and arranged in use to induce an electrostatic charge in said flow of flavouring.

2. An applicator as claimed in claim 1, including a receptacle for storing powdered flavouring and a powder accelerator disposed between the receptacle and the outlet, the powder accelerator comprising a first inlet for an airborne flow of powdered flavouring from the receptacle and a second inlet for a supply of gas, the second inlet surrounding the first inlet and being arranged so that gas flow from the second inlet causes acceleration of the particle flow from the first inlet

3. An applicator as claimed in claim 2, wherein the powder accelerator includes a third inlet for a supply of compressed gas, the third inlet surrounding the second inlet and being arranged so that the gas flow from the third inlet causes acceleration of the particle flow from the second inlet.

4. An applicator as claimed in claim 3 wherein the first, second and third inlets are concentric, the second inlet extending axially beyond the first inlet and the third inlet extending axially beyond the second inlet.

5. An applicator as claimed in claim 1, wherein the receptacle includes a fluidised bed.

6. An applicator as claimed in claim 5 wherein the receptacle includes an opening for introduction of powdered flavouring and an outlet or an airborne flow of powder, the outlet being located below the opening, one or more baffles located within the receptacle between the opening and outlet thereof.

7. An applicator as claimed in claim 6 wherein the baffles comprise a plurality of apertured plates each extending across the receptacle, apertures in adjacent plates being non-coincident.

8. An applicator as claimed in claim 7 wherein the plates are inclined to the horizontal.

9. An applicator as claimed in claim 6, wherein said one or more baffles comprises a helical lifting screw.