GB2095538A

GB2095538A - Method and apparatus for peeling vegetables such as potatoes

Info

Publication number: GB2095538A
Application number: GB8109741A
Authority: GB
Original assignee: BRINKMAN ROBERTUS HERMANUS NICOLAAS
Current assignee: BRINKMAN ROBERTUS HERMANUS NICOLAAS
Priority date: 1981-03-27
Filing date: 1981-03-27
Publication date: 1982-10-06

Abstract

An apparatus for removing the skin or peel of fruit or vegetables, particularly potatoes, comprises a nozzle 4 from which a gas flow having ice particles entrained therein is discharged against the skin etc of the vegetable etc. During the skinning process the vegetables or fruit may be supported, rotated and transported by a plurality of rotatable, longitudinally extending rollers 2 forming a trough- like arrangement, the rollers all being driven in the same direction. After peeling the vegetables are washed with water from a nozzle 5. <IMAGE>

Description

SPECIFICATION Method and apparatus for removing the skin of vegetables and fruit, particularly of potatoes.

The present invention relates to a method and apparatus for removing the skin of vegetables and fruit, particularly potatoes.

Several methods of peeling large volumes of potatoes suitable for use on a commercial scale are known.

In one such known process, the potatoes are introduced into a container having an inner wall surface made of an abrasive material the potatoes being rotated or tumbled so as to contact the abrasive material which removes the peel. This method causes a relative large wastage of edible potato and necessitates a relatively large water consumption.

Moreover, utilising such a process, the eyes of the potatoes are not removed.

In other known methods, the potato peel is removed utilising steam or a heated lye bath.

These processes also suffer from the disadvantage of a relative large wastage of edible potato and a relative high water consumption.

A further drawback of all of these known methods is the unattractive appearance of the peeled potatoes.

The present invention seeks to provide a method and apparatus for removing the skin of fruit or vegetables, particularly potatoes, whereby little of the edible portion of the fruit or vegetabie is wasted.

Moreover, the present invention seeks to provide a method and apparatus necessitating the use of considerably less water and energy compared with known methods.

According to the present invention, there is provided a method of removing the skin or peel of fruit or vegetables such as potatoes wherein a gas flow having particles of ice entrained therein is directed against the fruit or vegetable.

The gas stream, usually an air stream, having particles of ice entrained therein is used to skin or peel the fruit or vegetables.

This means that no pollution of surface water occurs, while the water and energy consumption required by the method are much lower than in known methods.

The ice particles may be obtained in various ways.

Thus, in a preferred embodiment, the ice is produced by wetting a rotating, refrigerated cylinder, the ice thus formed being scraped from the cylinder and being mixed with the gas flow, whereupon it is blown or blasted onto the vegetables or fruit to be peeled.

It is also desirable if the ice scraped from the cylinder prior to being mixed with the gas flow, is ground to reduce the size of the ice particles.

The water from which the ice is to be produced may have additives admixed therewith.

In a preferred embodiment, the water has 0,1 % of a salt, desirably sodium chloride, admixed therewith.

The addition of the salt promotes the formation of small ice particles which may easily be entrained in the gas flow. During the skinning or peeling, the fruit or vegetables are advantageously rotated so as to expose substantially all of their surface portions to the gas flow.

Such rotation, particularly in the region where the fruit or vegetables are subjected to the gas flow, may be effected by means of a plurality of longitudinally extending rollers forming a trough-like arrangement which supports the vegetables or fruit.

The rollers are spaced apart and are rotated in the same direction.

If desired, the rollers may be provided with protuding or roughened portions on their curved surfaces which promote the rotation of the fruit or vegetables by the rollers. In a preferred embodiment, at least a portion of the curved surfaces of the rollers are provided with one or more grooves or screw-threads, by means of which an axial movement in the longitudinal direction of the rollers is given to the vegetables or fruit.

By so doing, the vegetables or fruit to be peeled are continually rotating whilst passing through the skinning or peeling region.

The skin or peel is blown or blasted from the vegetables or fruit by the gas flow having the ice particles entrained therein.

In a advantageous embodiment, the water form which the ice particles are prepared, is cooled to below 0 C at an elevated pressure.

This is then sprayed through a nozzle into the gas flow, the supercooled water crystallising in the gas flow to form ice particles.

The elevated pressure and the temperature to which the water is supercooled may be varied as desired.

The gas flow itself may also be supercooled to below 0 C. The temperature of below 0 C.

for the gas flow desirably exists at the location at which either the ice particles or the water to be crystallised enter the gas flow. Desirably, however, the temperature is so selected that the gas has attained a temperature not less than 0 C. when it strikes the vegetables or fruit so that the skinned vegetables do not become frozen.

Fig. 1 is a longitudinal sectional view of an apparatus in accordance with the present invention corresponding to a view taken along the line a-a of Fig. 2.

Figure 2 is a sectional view taken, along the line b-b of Fig. 1.

Figure 3 is a diagrammatic view of an apparatus for producing an airstream having particles of ice entrained therein Figure 4 is a diagrammatic view of another embodiment of such apparatus.

As shown in Fig. 1 and Fig. 2, the apparatus comprises a housing a having an inlet 6 and an outlet 7.

In the housing 1, a plurality of rotating longitudinally extending rollers 2 are mounted so as to define a trough through which potatoes 3 pass during their passage from the inlet 6 to the outlet 7.

During such movement along the trough, the potatoes are rotated by the rotating rollers 2.

This causes various surface portions of the potatoes to pass under a nozzle 4, from which an air stream having particles of ice entrained therein emanates.

The effect of the ice-containing air stream on the potatoes is to cause the peel thereof to be removed.

After the peel has been removed, the potatoes pass beneath a second nozzle 5 from which water emanates so as to clean the potatoes.

The washing water, after cleaning the potatoes, flows downwardly between the rollers 2 into a lower portion of the housing and is then drained off or recirculated.

As is shown in Fig. 3, there is provided a rotating refrigerated cylinder 8, onto which water from a conduit 9 is directed. The ice formed is scraped from the cylinder by a member 10 and is ground to smaller particles by a grinder 11. The ice particles then are introduced into the air stream flowing through the conduit 1 2 to be blown through the nozzle 5 against the potatoes to be peeled.

As is shown in the embodiment according to Fig. 4, the air stream and the water stream from which the ice particles are to be obtained, pass through the refrigerating means 13, by which the air and the pressurized water are cooled down below 0 C. to be directed then through the nozzle 5 onto the potatoes to be peeled.

By its pressure drop, the supercooled water, when leaving the nozzle 5, will crystallize to small ice particles, which are entrained by the air stream emanating from the nozzle 5.

Claims

1. A method of removing the skin or peel of fruit or vegetables such as potatoes wherein a gas flow having particles of ice entrained therein is directed against the fruit or vegetables.

2. A method as claimed in claim 1, wherein the ice particles are formed by directing water onto a rotating refrigerated cylinder, the ice thus formed being scraped from the cylinder and being mixed with the gas flow and thereafter being blown or blasted onto the vegetables or fruit to be skinned or peeled.

3. A method as claimed in claim 2, wherein the dimensions of the particles of ice scraped from the cylinder are reduced by grinding before the particles are mixed with the gas flow.

4. A method as claimed in claim 2 or 3, wherein the water used for producing the ice contains about 0,1% of a salt.

5. A method as claimed in claim 4, wherein the salt is sodium chloride.

6. A method as claimed in any preceding claim, wherein the vegetables or fruit are rotated whilst being subjected to the force of the gas flow.

7. A method as claimed in claim 1, wherein the water used for forming the particles of ice is under an elevated pressure and is supercooled to below 0 C., the supercooled water being sprayed through a nozzle into the gas flow so as to crystallize in the gas flow to form particles of ice.

8. A method as claimed in any preceding claim, wherein the gas flow, at least in the region of the introduction of the ice particles therein or of the introduction of the water from which the ice particles are produced, is supercooled to a temperature of below 0 C.

9. A method as claimed in any preceding claim, wherein the temperature of the gas flow in the region of the fruit or vegetables to be peeled is not lower than 0 C.

10. An apparatus for removing the skin or peel of vegetables or fruit comprising at least one nozzle for directing a gas flow onto the vegetables or fruit to be skinned or peeled, the nozzle including means for introducing ice particles into the gas flow and/or means for forming such ice particles in the gas flow, means being provided for supporting and transporting the vegetables or fruit in and through the path of the gas flow from said nozzle.

11. An apparatus as claimed in claim 10 additionally comprising means for rotating the vegetables or fruit, at least whilst said vegetables or fruit are located in the path of said gas flow.

1 2. An apparatus as claimed in claim 11, wherein said means for rotating the vegetables or fruit also form said support and transportation means, said means for rotating said vegetables or fruit comprising a plurality of rotatable, longitudinally extending rollers, all being driven in the same direction.

1 3. An apparatus as claimed in claim 13, wherein the rollers over at least a portion of their curved surfaces are provided with one or more grooves or screw threads for providing an axial movement transversely to the longitudinal direction of the rollers to the vegetables or fruit whereby the vegetables or fruit are continuously transported and rotated through the path of the gas flow.

14. A method of removing the skin or peel of vegetables or fruit substantially as hereinbefore described.

1 5. An apparatus for removing the skin or peel from vegetables or fruit constructed and arranged to operate substantially as hereinbe fore described with reference to and as illustrated in the accompanying drawings.