GB2351896A

GB2351896A - Washing root vegetables

Info

Publication number: GB2351896A
Application number: GB0013364A
Authority: GB
Inventors: Bo Jonsson
Original assignee: Limas AB
Current assignee: Limas AB
Priority date: 1999-06-02
Filing date: 2000-06-01
Publication date: 2001-01-17
Anticipated expiration: 2020-06-01
Also published as: SE9902039D0; GB0013364D0; NL1015152A1; NL1015152C2; DE10027056B4; GB2351896B; SE9902039L; SE518555C2; DE10027056A1

Abstract

A machine for washing root vegetables comprises a bath of washing liquid in which the vegetables can be placed, and a driving element for subjecting the washing liquid to a power flow. The driving element is preferably a paddle. The vegetables may be supplied to a first container 4 in the washing liquid and subsequently moved to successive containers 4, and discharged from a last container 6. The washing liquid is preferably supplied in the opposite direction to the movement of the vegetables in a counterflow manner. The containers may have an intermediate bottoms above the bottom of the containers, with the driving element placed below the intermediate bottoms. The intermediate bottoms are displaceable for moving the root vegetables from one container to the next. The vegetables are preferably washed subsequent to peeling to aid their preservation. Sodium bisulphite may be added to the washing liquid to improve the keeping qualities, and reduce discolouration of peeled vegetables such as potatoes.

Description

2351896 A METHOD AND A MACHINE FOR WASHING ROOT VEGETABLES The present

invention relates to a method and a machine for washing root vegetables, especially potatoes, preferably 5 subsequently to the peeling of the root vegetables.

When potatoes are peeled the cells of the potatoes are damaged and the substances present in the cells provide for a discolouration of the potatoes and also to the potatoes having restricted keeping qualities. In order to rectify these drawbacks the potatoes are subsequently to the peeling washed in for example a washing liquid containing sodium bisulphite in order to remove from the surface of the potatoes the substances which have forced out from the cells damaged at the peeling. Previously known methods and machines for such washing have restricted efficiency and do not provide that the potatoes obtain the necessary keeping qualities.

The object of the invention is to provide a method and a machine for washing root vegetables, especially potatoes, so that the root vegetables are provided with improved keeping qualities.

In order to comply with this object the root vegetables are positioned in a washing liquid bath and the method according to the invention is characterized in that the washing liquid is in the course of the washing action subjected to a powerful flow movement. It is thereby preferred that the root vegetables are arranged in containers provided with openings, that the containers are positioned in the washing liquid and that the washing liquid is subjected to its flow movement by means of driving elements positioned outside the containers.

The powerful flow movement provides that the substances which have forced out from the damaged cells are efficiently removed at the same time as the root vegetables are not contacted by any mechanical devices which could lead to further cells being damaged and the substances present in the cells being forced out therefrom.

2 In a preferred embodiment of the method according to the invention the root vegetables are during the washing operation supplied to a first container, whereupon the root vegetables are after parts of the washing operation successively moved to subsequent containers and are finally discharged from a last container. It is also preferred that the washing liquid is supplied to the last container and flows through the containers to the first container from which the washing liquid is discharged, so that the root vegetables and the washing liquid move in opposite directions.

The invention comprises also a machine for washing root vegetables, the machine comprising a container for washing liquid in which the root vegetables are placed. The machine is characterized by a driving element for providing the washing liquid with a powerful flow movement. It is thereby suitable that the container has an intermediate bottom which is provided with openings and is positioned at a distance above the bottom of the container, the root vegetables being supported by the intermediate bottom, and that the driving element is positioned below the intermediate bottom. It is suitable that the driving element is constituted by a revolving paddle which is adapted at its revolving movement to force the washing liquid through the intermediate bottom into and out from the part of the container in which the root vegetables are positioned.

In a preferred embodiment of the machine according to the invention the machine comprises several successively after each other positioned containers and a device for successively moving the root vegetables from a first to a last container during the washing operation. It is thereby suitable that the intermediate bottoms of the containers are displaceable up from the containers to the lower part of spaces separated from each other by means of intermediate walls, the spaces corresponding to the number of containers, the intermediate walls being displaceable for moving the root vegetables of the different containers to a position 3 above the next container, the intermediate bottoms being adapted to be lowered down into the containers, so that the root vegetables are successively moved from the first to the last container.

It is also suitable that the machine according to the invention works according to the counter-flow principle, i.e. so that the washing liquid in the machine flows in the opposite direction in relation to the movement of the root vegetables from the first to the last container. In accordance therewith a connection for the supply of washing liquid is connected with the last container and an outlet for washing liquid is provided at the first container. openings provided with check valves are positioned between the containers so as to allow the washing liquid to flow through the containers from the last to the first container.

The method and the machine according to the invention provide for an efficient washing of peeled potatoes so that the potatoes are subsequently to the peeling provided with very good keeping qualities.

A method, and a machine, in accordance with the present invention will now be described in more detail, by way of example only, with reference to the accompanying drawings in which:

Fig. 1 is a side view of a machine according to the invention; Figs 2. and 3 show the machine from opposite ends; Fig. 4 is a plan view of the machine; Fig. 5 is a section through the machine taken along the line A-A in Fig. 4; and Fig. 6 is a section through the machine taken along the line B-B in Fig. 4.

A machine according to the invention is adapted for washing knife-peeled potatoes and has the object of removing the substances present in the cells of the potatoes, damaged by means of the peeling, said substances causing discolouration and shortened keeping qualities of the peeled potatoes.

4 The machine comprises a feeding section 2, four containers 4 for washing liquid and washing of the potatoes and a discharging section 6. From the discharging section 6 the potatoes are supplied to a system for weighing up and 5 packeting the potatoes.

The containers 4 for washing liquid and potatoes each has (see Fig. 5) a lower part 8 having a half-circular section and an upper part 10 for containing the potatoes. In each container there is an intermediate bottom 12 which is movable in a vertical direction and is provided with openings, the intermediate bottoms being in all drawings shown in an upper position. The intermediate bottoms 12 are displaceable from the upper position shown in the drawings to a lower position just above the lower parts 8 of the containers. The vertical movement of the intermediate bottoms 12 takes place by means of a bar 14 which is driven by means of a motor through a gear-wheel 16.

In the lower part 8 of each container 4 there is a paddle 18 supported by one shaft 20 each. The shafts 20 are connected with one arm 22 each (see Fig. 1) which arms 22 are in turn connected with a beam 24 which is driven forward and back by means of an arm 28 connected with a rotatable wheel 26. When the wheel 26 rotates and the beam 24 is displaced forward and back by means of the arm 28, the shafts 20 are rotated which in turn provides that the paddles 18 are rotated forward and back in the lower parts 8 of the containers 4 between substantially horizontal positions, the rotation movement preferably comprising 1500. The rotational movements of the paddles 18 provide that the washing liquid in the containers 4 is at one side of the containers forced up through the openings in the intermediate bottoms 12 and is at the other side sucked through these openings from the upper parts 10 of the containers to the lower parts 8 of the containers and vice versa. This provides for a powerful flow of the washing liquid through the upper parts 10 of the containers 4 which in turn provides for an efficient washing of the potatoes positioned therein.

During the washing operation the potatoes are intermittently displaced from the leftmost container 4 (see 5 Fig. 5) to the containers positioned to the right thereof. This displacement takes place by means of walls 30 which are connected to a driving system working by means of a plunger 32. When the intermediate bottoms 12 are positioned in their upper positions, the walls 30 are displaced to the right in correspondence to the width of one container 4, this movement providing that the potatoes positioned in the feeding section 2 are displaced to a position above the leftmost container 4, while the potatoes which have been lifted from the leftmost container 4 by means of the upward displacement of the intermediate bottom 12 are displaced to a position above the next container 4 to the right and so on, while the potatoes which have been lifted from the rightmost container 4 are discharged to a position above a drainage container 34. The potatoes which have been moved up from the drainage container 34 are by means of an intermediate wall 30 fed to the discharge portion 6. The intermediate bottoms 12 are thereupon lowered to the position above the container parts 8 whereupon the walls 30 return to their original left position and the washing of the potatoes in the containers 4 is continued by driving the paddles 18.

The washing liquid, which consists of water with the addition of sodium bisulphite in an amount of for example 0.5 - 1%, is fed to the rightmost container 4 and then flows to the left (see Fig. 5) to the following containers 4 through openings 36 provided with check valves in the walls between the upper parts 10 of the containers 4. The washing liquid then flows out from the leftmost container 4 through a spillway outlet. This reverse flow principle provides that the potatoes at each successive displacement from the leftmost container 4 to the right to the following 6 containers will be treated by means of a washing liquid which is successively cleaner.

For the washing of 1,000 kg potatoes there is in the normal case required 500 litres of water which at the machine described above takes about one hour. The amount of potatoes positioned in each container 4 amounts in the normal case to 10 - 15 kg.

The flow of washing liquid provided by means of the paddles 18 causes an extremely efficient removal of the substances which at the peeling have been uncovered by the damage of the cells of the potatoes. This efficient removal of said substances provides that the peeled potatoes can be stored for a much longer time than has previously been possible.

7

Claims

1. A method for washing root vegetables, preferably subsequently to the peeling of the root vegetables, comprising positioning the root vegetables in a bath of washing liquid and, during the washing operation, subjecting the washing liquid to a powerful flow movement.

2. A method according to claim 1, in which the root vegetables are positioned in containers which are provided with openings and which are positioned in the washing liquid.

3. A method according to claim 2, in which the washing liquid is provided with its flow movement by means of driving elements positioned outside the containers.

4. A method according to any preceding claim, in which the root vegetables are supplied to a first container, after parts of the washing operation are successively moved to subsequent containers and are at last discharged from a last container.

5. A method according to claim 4, in which the washing liquid is supplied to the last container and is conducted through the containers to the first container from which the washing liquid is discharged.

6. A machine for washing root vegetables, preferably subsequently to the peeling of the root vegetables, comprising a container for washing liquid in which the root vegetables are to be positioned, and a driving element for providing the washing liquid with a powerful flow movement.

7. A machine according to claim 6,in which the container is provided with an intermediate bottom supporting the root vegetables, the intermediate bottom is provided 8 with openings and is positioned at a distance above the bottom of the container, and the driving element is arranged below the intermediate bottom.

8. A machine according to claim 7, in which the driving element is constituted by a rotatable paddle which is adapted at its rotational movement to drive the washing liquid through the intermediate bottom into and out from the part of the container in which the root vegetables are positioned.

9. A machine according to any of claims 6 to 8, in which several of the containers are positioned following each other and a device is provided for successively displacing the root vegetables from a first to a last of the containers during the washing operation.

10. A machine according to claim 7 and claim 9, in which the intermediate bottoms of the containers are displaceable up from the containers to a position at the lower part of spaces separated from each other by means of intermediate walls and corresponding to the number of containers, the intermediate walls are displaceable for moving the root vegetables from above one of the containers to a position above the next container, and the intermediate bottoms are adapted to be lowered down into the containers whereby the root vegetables are successively moved from the first to the last container.

11. A machine according to claim 9 or claim 10, in which a connection for the supply of washing liquid is connected to the last container, openings provided with check valves are positioned between the containers allowing the washing liquid to flow through the containers from the last to the first container, and a spillway outlet for washing liquid is positioned at the first container.

9

12. A machine for washing root vegetables substantially as hereinbefore described with reference to the accompanying drawings.