BE1027385B1 - ESTABLISHMENT AND METHOD FOR PROCESSING LEAF VEGETABLES - Google Patents

Abstract

The present invention relates to a method for processing leafy vegetables, comprising in a first stage the homogeneous lay out of leaf vegetables, said first stage comprising the steps of: (a) supplying an amount of leafy vegetables, comprising a plurality of individual leaves; (b) blowing the supplied quantity of leaf vegetable into the air by means of one or more air currents through the leaf vegetable, whereby the individual leaves of the leaf vegetable whirl up; and (c) collecting whirled individual leaves of the leaf vegetable on a collecting surface, the collecting surface being a moving surface on which the individual leaves whirl down and thus form a homogeneously spread layer. A second aspect relates to a device for processing leafy vegetables, comprising a supply device, one or more blowing devices and a movable collecting surface, wherein substantially perpendicular to the movable collecting surface, one or more walls extend defining a space suitable for delimiting a container. whirling scroll volume.

Description

t BE2019 / 5396

ESTABLISHMENT AND METHOD FOR PROCESSING LEAF VEGETABLES

TECHNICAL FIELD The invention relates to the laying out and cleaning of leafy vegetables. More specifically, the invention is in the technical field of spinach and chard processing.

STATE OF THE ART In the vegetable processing industry, and particularly in the processing of leafy vegetables, the bulk vegetable material consists essentially of a wide variety of leaf material, including valuable and less valuable material, as well as some amount of contaminants. Classification and purification of the individual components is therefore necessary for the further processing of leafy vegetables. However, with this classification and purification of leaf material, the problem arises that the impurities contained in this leaf material are only difficult to remove. This is due to the natural phenomenon that individual leaves tend to stick or stick together, so that contaminants are trapped in the leaf mass, as it were. This makes the cleaning and sorting process a very difficult and intensive task, which still involves a great deal of manual work, and whereby the purity and quality finally obtained leaves something to be desired. In addition, new problems with regard to purity in leafy vegetables arise today, in particular the presence of plastic or metal particles in the crops. A number of ways are already known from the current state of the art in which this process is partially automated. However, the cleaning and sorting of leafy vegetables remains subject to some difficulties. For example, DE 10 2008 058 998 describes a method for the screening or classification of cut vegetable and herb material, in which a vertical air flow allows to separate different types of plant material on the basis of specific weight. However, here the separated plant material is recollected as a bulk stream and the individual leaves are not explained. In addition,

? BE2019 / 5396 The removal of contaminants of unknown specific gravity is difficult to achieve.

Furthermore, DE 4427 418 describes a separation system comprising a swirl chamber. The device is suitable for detaching individual leaves from bulk plant material and allows the separation of different types of plant material based on specific weight. However, similar to DE ‘998, the separated material is recollected and impurities are removed only to a limited extent.

US 2 666 711 describes an apparatus suitable for washing and drying spinach. Contaminants are only partially removed, with the focus on removing soil remnants.

Accordingly, there is a need for a method of processing leafy vegetables in which the leafy vegetable is thoroughly cleaned and where the leafy vegetable is not treated as bulk material, but in which individual leaves are considered. In particular, a higher purity is hereby obtained, whereby the individual leaves are evenly spread, and whereby sorting, classification, freezing and / or other processing steps are further simplified and optimized.

The present invention aims to solve at least some of the above-mentioned problems or drawbacks.

SUMMARY OF THE INVENTION To this aim, the invention provides in a first aspect a method according to claim 1, comprising the steps of: (a) supplying an amount of leafy vegetable comprising a plurality of individual leaves; (b) blowing the supplied quantity of leaf vegetable into the air by means of one or more air currents through the leaf vegetable, whereby the individual leaves of the leaf vegetable whirl up; and (c) collecting whirled up individual leaves of the leaf vegetable on a collecting surface. The method is characterized by the collecting surface, which surface is a moving surface on which the individual leaves thus whirl down and form a homogeneously spread layer.

Preferred forms of the method are given in sub-claims 2 to

11. The method of the present invention allows the simultaneous spreading of leaves, and the separation of both large and small impurities. This is particularly relevant since leaf vegetables are processed in large quantities and it is currently very difficult to remove coarse dirt particles such as soil, sand, small pieces of waste material, for example plastics, insects or other small animals, from the leaf vegetable. The present method allows the leaves to be spread quickly and efficiently, such dirt particles being spread next to the leaves in a simple and effective manner, whereby they can be easily distinguished from said leaves, and subsequently removed, for instance by optical sorting.

A second aspect of the present invention relates to a device according to claim 12, comprising a supply device, one or more blowing devices and a movable collecting surface, wherein extending substantially perpendicular to the movable collecting surface, one or more walls defining a space suitable for bounding. of a whirling volume of scrolling.

Preferred forms of the device are given in sub-claims 13 to 13

17.

DESCRIPTION OF THE FIGURES Figure 1 shows a schematic representation of an embodiment of the method for processing leafy vegetable, wherein the amount of leafy vegetable is blown into the air by one air stream.

Figure 2 shows a schematic representation of a further or different embodiment of the method for processing leafy vegetables, in which the amount of leafy vegetables is blown into the air by means of one air flow and one counter-air flow.

Figure 3 shows a schematic representation of an embodiment of the apparatus for processing leafy vegetables according to the present invention.

DETAILED DESCRIPTION The present invention relates to a method for processing leafy vegetables.

Unless defined otherwise, all terms used in the description of the invention, including technical and scientific terms, have the meaning as commonly understood by those skilled in the art of the invention. For a better assessment of the description of the invention, the following terms are explicitly explained.

“A”, “the” and “the” in this document refer to both singular and plural unless the context clearly suggests otherwise. For example, “a segment” means one or more than one segment.

When “about” or “around” is used in this document for a measurable quantity, parameter, time or moment, and the like, it means variations of +/- 20% or less, preferably +/- 10% or less, more preferably +/- 5% or less, even more preferably +/- 1% or less, and even more preferably +/- 0.1% or less than and of the quoted value, to the extent that such variations of are applicable in the described invention. However, this should be understood to mean that the value of the quantity using the term “approximately” or “round” is itself specifically disclosed.

The terms “comprise”, “comprising”, “consist of”, “consisting of”, “incorporating”, “containing”, “containing”, “containing”, “containing” are synonyms and are inclusive or open terms that define the indicate the presence of what follows, and which do not exclude or prevent the presence of other components, features, elements, members, steps known from or described in the prior art.

Quoting numeric intervals through the endpoints includes all integers, fractions, and / or real numbers between the endpoints, including these endpoints.

In a first aspect, the present invention relates to a method for processing leafy vegetables, wherein the processing in a first phase comprises laying out leafy vegetables homogeneously. The method comprises the steps of: (a) supplying a quantity of leaf vegetable comprising a plurality of individual leaves; (b) blowing the supplied quantity of leafy vegetable into the air by means of one or

> BE2019 / 5396 multiple air currents through the leafy vegetable, whereby the individual leaves of the leafy vegetable whirl up; and (c) collecting whirled individual leaves of the leaf vegetable on a collecting surface, said collecting surface being a moving surface on which the individual leaves whirl down and thus form a homogeneously spread layer. The term "lay out" in the context of the present invention refers to evenly spreading, spacing and / or scattering leaves. Laying out leaves leads to a final state in which the individual leaves confine, preferably do not touch, and are not matted or stuck together. A clear distinction can be made here between the leaves and any impurities present, since these impurities are located on and / or next to the spread leaves.

The term “leaf vegetable” or “leaf vegetable” designates any vegetable from, but is not limited to, the group of endive, radicchio, cardoon, parsley, purslane, leek, vegetable celery, lettuce, iceberg lettuce, curly lettuce, romaine lettuce, romaine lettuce, lamb's lettuce , Swiss chard, spinach, garden cress, garden cress, watercress, winter purslane, or combinations thereof. The present invention primarily wishes to focus on explaining spinach and / or Swiss chard.

The "whirling" of individual leaves, in the context of the present invention, refers to the state of the leaves in which they are in a floating state under the influence of an air flow. The term "whirl up" refers to the transition from a supported state to a floating state, while the term "whirl down" refers to the transition from a floating state to a supported state.

A "collection surface" in the context of the present invention is any surface suitable for supporting leaves, preferably as they swirl down.

The method of the present invention allows the simultaneous spreading of leaves and the separation of impurities. This is particularly relevant since leaf vegetables are processed in large quantities and it is currently very difficult to remove dirt particles such as soil, sand, small pieces of waste material, for example plastics, insects or other small animals, from the leaf vegetable. The present method allows the leaves to be spread quickly and efficiently, removing such dirt particles in a simple and effective manner. Here coarse dirt particles are separated from leaves and smaller dirt particles, as the leaves and smaller dirt particles are blown away while the coarse dirt particles are not blown away and / or fall down. The moving collection surface ensures that the collected individual leaves and small dirt particles are spread homogeneously, preferably separately from each other. This makes it easy to distinguish residual dirt particles from the homogeneously spread leaves, enabling efficient removal thereof. This allows an efficient follow-up of the quality control of the process, and simplifies optional processing steps that follow the laying out of the leaves. In particular, processing steps such as optical sorting are exceptionally efficient due to the homogeneous distribution of the leaves and residual dirt particles. The cleaning and laying out process, which usually involves a great deal of intensive manual labor, is automated in its integrality thanks to the present invention.

Preferably, the direction of the one or more air flows is substantially parallel to the collecting surface. Due to this orientation, the whirling up of the leaves extends mainly in the length and / or width of the collecting surface, and to a lesser extent in the height. As a result, a more efficient and wider distribution of the leaves and impurities and / or foreign objects on the collecting surface is obtained, resulting in an optimal separation of impurities.

A movement, and especially when it concerns a rectilinear movement, is by definition defined by its “direction of movement” and “sense of movement”, or shortened “direction” and “sense”. The direction indicates the orientation of the linear motion relative to a reference point. In the context of the present invention, the collection surface is considered a reference point. A direction parallel to the collecting surface therefore implies that the line along which the rectilinear movement occurs is parallel to the collecting surface. On the other hand, the sentence determines whether it is a positive or negative movement that occurs along this line. Concretely, the same sense and same direction implies that two objects move together along the same line, whether or not at a different speed, while objects with the same direction but opposite sense, just move away from each other along this line.

The one or more air streams deviate in some embodiments from said substantially parallel orientation. Preferably, this deviation is no more than 90 ° with respect to the collecting surface. Air currents exhibiting greater deviations will either give rise to the leaves whirling up too high, with the result that an impractically large space has to be provided to contain the whirling leaves. On the other hand, too great a deviation can hinder the careful whirling of the leaves, as a result of which an undersized spread is ultimately obtained and / or whereby impurities cannot be sufficiently distinguished from the leaves. More preferably, the deviation is no more than 60 °, even more preferably no more than 30 °, most preferably no more than 10 °, with respect to the collecting surface.

According to a further or different embodiment, the sense of the one or more air flows is substantially the same as the sense of movement of the collecting surface. The present relationship between the sense of the one or more air flows and the sense of movement of the collecting surface makes it possible to supply the leafy vegetable only on one side of the collecting surface. As a result, the method can be regarded as a linear, fully continuous process, in which the leafy vegetable moves from the supply side, is whirled up under the influence of the one or more air currents, then whirls down onto, and is evenly spread over, the collecting surface. The surface further ensures the transport of the spread leaves in the same direction and sense of movement, until the discharge side is reached.

In some embodiments, at least one counter-air flow is additionally provided which has a substantially opposite sense to the sense of the one or more air flows. A counter-flow of air ensures a faster and more efficient swirling of the leaves. The spreading over the collecting surface is achieved in a shorter time, whereby optimum spacing between the individual leaves is obtained. This ensures a general efficiency increase of the method.

According to a further or different embodiment, the one or more air flows have a flow velocity which is comprised between 20.0 and 40.0 m / s. The speeds used have been optimally chosen in function of the whirling up and laying out of leafy vegetables, in particular spinach and chard. Speeds in the range mentioned are particularly suitable for leafy vegetables such as spinach and Swiss chard. The collecting surface in some embodiments moves in substantially the same direction as the one or more air currents, at a speed comprised between 0.25 and 10.00 m / s. In some embodiments, the moving collecting surface is a conveyor belt, where the direction of roll is substantially parallel to the one or more air streams, and the sense of roll is the same as the direction of these air streams.

In some embodiments, the capture surface includes two or more sub-surfaces, each of which travels at a different speed. Depending on the desired degree of spreading of the leaves on the collecting surface, the speed of the different sub-surfaces can be changed, so that the spread can be increased fractionally over the different sub-surfaces.

In some embodiments, the capture surface includes two or more conveyor belts, each moving at a different roller speed. The use of two or more conveyor belts has the advantage that they can be closely connected to each other, while a large difference in speed is realized. The "spread" of the leaves on the collecting surface is expressed in the context of the present invention as a percentage describing the ratio between the covered and uncovered surface of the collecting surface. In concrete terms, a degree of spread of, for example, 50% indicates that the collection surface is half covered, half uncovered with leaves. According to a further or different embodiment, the intended degree of spreading is between 50 and 100%, more preferably between 70 and 100%, most preferably between 80 and 95%. For this purpose, the collecting surface comprises at least three sub-surfaces, which travel at a respective speed comprised between 0.25 and 2.00 m / s, between 0.50 and 4.00 m / s and between 2.00 and 6.00 m / s m / s. With the current configuration, optimal spread is obtained for both spinach and chard, with visual quality control being exceptionally efficient. Preferably, the at least three sub-surfaces travel at a respective speed comprised between 0.75 and 1.25 m / s, between 2.75 and 3.25 m / s and between 3.75 and 4.25 m / s.

In a further or different embodiment, the individual leaves of the supplied leaf vegetable were previously released by vibration on one or more shakers. The term "vibration" or "oscillation" in the context of the present invention refers to a periodically repeated reversal of the direction of motion. A vibration is often caused by the disturbance of a stable equilibrium situation. In view of the invention, the vibration is caused by one or more "shakers", which are mechanical devices for purposefully generating a specific vibration. The prior vibration of the individual leaves ensures that any matted leaves loosen, so that whirling up is not impeded. Since the speed of the air currents is specifically chosen in function of the type of leafy vegetable to be laid out, leaves must also be effectively introduced into the air stream as separate units if they are to whirl up in a predictable manner. In some embodiments, the conveyor belt supplying the leaf volume also acts as a shaker.

In some embodiments, leaf vegetable processing includes one or more process steps selected from the group of washing, drying, optical sorting, packaging, freezing, or combinations thereof.

The term “optical sorting” refers to sorting based on visual properties. It may be sorted and / or classified based on size, color, consistency, or other appearance characteristics. Preferably, the optical sorting is automated, this maximizes the yield while less waste is generated. Moreover, throughout the production process of vegetables, for example, a reduction in energy consumption can be obtained and the use of chemicals is minimized. Automated optical sorting also allows high productivity and throughput, and is an important link in ensuring consistent food security and food quality.

According to a further or different embodiment, the processing of leaf vegetable comprises at least sorting, washing and freezing the leaf vegetable. The first phase, comprising explaining individual leaves, allows for a more efficient sorting as leaves are easier to distinguish individually and therefore defects are more quickly noticed. Sorting of a homogeneously spread layer of leaves also takes place with a smaller risk of errors. Washing and freezing is also more efficient starting from a homogeneously spread layer of leaves, as a larger surface area is exposed to the washing liquid and / or cooling of the leaves is faster due to a larger exposed cooling surface.

A second aspect of the present invention relates to an apparatus for processing leafy vegetables, comprising a supply device, one or more blowing devices and a movable collecting surface, wherein extending substantially perpendicular to the movable collecting surface, one or more walls defining a space suitable for limiting a whirling leaf volume.

The space defined by said walls is further suitable for delimiting a swirling leaf volume.

The defined space is also described in the following by the term “bladder cage”. In the context of the present invention, the bladder cage comprises one or more contiguous or non-contiguous walls, which stop, guide and / or define the whirling leaves in one or more directions and / or dimensions.

The whirling of the leaves may take place in such a turbulent manner that there is a risk that the leaves will move outside the establishment, the business environment, or the area to be controlled by the employee (s).

The blowing cage thus ensures that a controllable process is obtained, in which the operating environment remains clean, the processing of the leafy vegetables is efficient and hygienic and possible product loss is minimized.

According to one embodiment, the blowing cage limits a volume which is comprised between 20 and 200 m3. The bladder cage allows the leaves to whirl smoothly, resulting in an optimal spread.

The dimensions of the blowing cage are also suitable for smooth, regular cleaning and maintenance.

The limited volume is preferably comprised between 40 and 120 m3, more preferably between 60 and 100 m3. Most preferably, the blowing cage limits a volume comprised between 80 and 90 m3. In order to limit only the whirling leaf volume within the defined space, but to allow the one or more air flows to move freely, according to one embodiment the one or more walls are at least partially air-permeable.

According to one embodiment, the one or more walls are an air-permeable mesh, grid and / or grille.

The one or more blowers are preferably configured substantially parallel to the collection surface.

By this is meant that the direction of an air flow generated by the one or more blowing devices is substantially parallel to the collecting surface.

Preferably, the one or more blowers are configured so that the generated air flows do not deviate more than 30 ° from the collecting surface.

Air currents which show larger deviations will either give rise to a whirling up too high

+ BE2019 / 5396 the leaves, with the result that an impractically large bladder cage must be provided to confine the whirling leaves.On the other hand, too large a deviation can hinder the careful whirling of the leaves, resulting in an undersized spread and / or whereby impurities are insufficiently removed from the leafy vegetable. More preferably, the deviation is no more than 20 °, even more preferably no more than 10 °, most preferably no more than 5 ° with respect to the collecting surface.

According to a further or different embodiment, the collecting surface comprises two or more partial surfaces. This makes it possible to advance the different partial surfaces at a different speed, so that the desired spread of the homogeneously distributed layer of leaves can be accurately selected and / or adjusted. Such a choice and / or adjustment takes place, inter alia, in function of the type of leaf crop, or, for instance, in function of the growth stage in which said leaf crop is located.

The collecting surface and / or the partial surfaces of the collecting surface comprise, according to one embodiment, one or more conveyor belts. Conveyor belts have the advantage that they fit closely together and can be easily adjusted to different speeds. Leaves that move from one conveyor belt to another at different speeds are not damaged.

According to a further or different embodiment, the device further comprises one or more components selected from the group of a washing device, a drying device, an optical sorting device, a packaging device, a freezer, or combinations thereof. Incorporating different process steps in the same device ensures increased efficiency and allows continuous processing from harvest to packaging.

According to one embodiment, the device comprises at least one device for optical sorting, a washing device and a freezer. Sorting by means of the present device is extremely efficient as leaves are easier to distinguish individually and defects are therefore more readily noticed when they are laid out homogeneously on a surface. Sorting of a homogeneously spread layer of leaves also takes place with a smaller risk of errors. Washing and freezing is also more efficient starting from a homogeneously spread layer of leaves, as a larger surface area is exposed to the washing liquid and / or cooling of the leaves is faster due to a larger exposed cooling surface.

In what follows, the invention is described by means of non-limiting figures illustrating the invention, and which are not intended or should not be construed to limit the scope of the invention.

DETAILED DESCRIPTION OF THE FIGURE The method for processing leafy vegetable (1) schematically shown in Figure 1 shows an amount of leafy vegetable (1) to be laid out, which is brought into a blowing cage (12) by means of a conveyor belt and / or shaker (15). In the bladder cage (12), the leafy vegetable (1) is exposed to an air flow (3), causing the leafy vegetable (1) to whirl up in the bladder cage (12) as individual leaves (2). The bladder cage (12), or the space containing the whirling leaves (2), extends so that the leaves (2) initially move upward (4) in the bladder cage (12), after which they whirl down again (5). The individual leaves (2) here whirl down (5) on a collecting surface (6) that moves (8) away from the blowing cage (12). The leaves (2) are spread under the influence of the air flow (3) in such a way that they are discharged as a homogeneously laid out layer (7) by means of the collecting surface (6). Here, any foreign objects and / or dirt particles are open, and clearly visible, spread on the collecting surface, which simplifies their removal in subsequent steps. Figure 2 shows a similar method, in which the amount of leafy vegetable (1) is blown into the air by one air stream (3), and is deposited accelerated on the collecting surface by one counter-air stream (9). The collecting surface according to the embodiment shown in Figure 2 comprises a first (6), second (6 ”) and third (6” ”) sub-surface, each of which is located with a respective first (8 '), second (8”) and third ( 8 ””) moving forward speed. The different movement speeds promote a homogeneous spreading of the leaves (2) into a homogeneously laid out layer (7), whereby any foreign objects and / or dirt particles can be easily distinguished and removed. Figure 3 shows a schematic representation of an embodiment of the apparatus for processing leafy vegetables according to the present invention. The device comprises a blowing cage (12) provided with a blowing device (13), suitable for homogeneously laying out an amount of leafy vegetables. Behind the bladder cage a collecting surface is provided, comprising a first (6), second (6 ") and third (6" ") sub-surface.

The device is particularly suitable for laying out individual leaves of a quantity of leafy vegetable homogeneously, whereby an unambiguous visual distinction can be made with potentially present foreign objects and / or dirt particles.

Smaller contaminants are removed during the blowing process and can be collected in a container (14) provided for this purpose. In front of the bladder cage (12), there are two shakers (11), which are adapted to separate the leaves from each other before laying out.

This is particularly advantageous if the leaves are previously washed and / or dried in a washing and / or drying device (10). The different parts of the device are mutually connected by means of different conveyor belts (15).

Claims (17)

CONCLUSIONS A method for processing leafy vegetables, wherein the processing comprises in a first phase laying leafy vegetables homogeneously, said first phase comprising the steps of: a. Supplying an amount of leafy vegetable, comprising a plurality of individual leaves; b. blowing the supplied quantity of leaf vegetable into the air by means of one or more air currents through the leaf vegetable, whereby the individual leaves of the leaf vegetable whirl up; c. collecting whirled individual leaves of the leaf vegetable on a collecting surface, said collecting surface being a moving surface on which the individual leaves whirl down and thus form a homogeneously spread layer. 2. A method according to claim 1, characterized in that the direction of the one or more air flows is substantially parallel to the collecting surface. A method according to claim 1 or 2, characterized in that the sense of the one or more air flows is substantially equal to the sense of movement of the collecting surface. A method according to any one of the preceding claims 1-3, characterized in that additionally at least one counter-air flow is provided which has a substantially opposite sense to the sense of the one or more air flows. A method according to any one of the preceding claims 1-4, characterized in that the one or more air streams have a flow velocity which is comprised between 20.0 and 40.0 m / s. 6. A method according to any one of the preceding claims 1 - 5, characterized in that the collecting surface moves in substantially the same direction as the one or more air streams, with a speed comprised between 0.25 and 10.00 m / s. A method according to any one of claims 1 to 6, characterized in that the collecting surface comprises two or more sub-surfaces, each of which moves at a different speed. Method according to claim 7, characterized in that the collecting surface comprises at least three sub-surfaces, which travel at a respective speed comprised between 0.25 and 2.00 m / s, between 0.50 and 4.00 m / s. s and between 2.00 and 6.00 m / s. A method according to any one of the preceding claims 1-8, characterized in that the individual leaves of the supplied leafy vegetable are loosened prior to laying out by means of vibration on one or more shakers. A method according to any one of the preceding claims 1-9, characterized in that the processing of leafy vegetables comprises one or more process steps selected from the group of washing, drying, optical sorting, packaging, freezing, or combinations thereof. A method according to any one of the preceding claims 1-10, characterized in that the processing of leaf vegetable comprises at least sorting, washing and freezing the leaf vegetable. 12. Device for processing leafy vegetables, comprising a feeding device, one or more blowing devices and a movable collecting surface, characterized in that substantially perpendicular to the movable collecting surface, one or more walls extend which define a space suitable for delimiting a whirling volume of scrolling. Apparatus according to claim 12, characterized in that the one or more blowing devices are configured substantially parallel to the collecting surface. Device as claimed in claim 12 or 13, characterized in that the collecting surface comprises two or more partial surfaces. A device according to any one of the preceding claims 12-14, characterized in that the collecting surface and / or the partial surfaces comprise one or more conveyor belts. A device according to any one of the preceding claims 12-15, characterized in that the device further comprises one or more components selected from the group of a washing device, a drying device, an optical sorting device, a packaging device, a freezer device, or combinations. of it. A device according to any one of the preceding claims 12-16, characterized in that the device comprises at least one device for optical sorting, a washing device and a freezer.