WO2003051162A1

WO2003051162A1 - Method of preparing fruit and vegetable products to be dehydrated, and apparatus for carrying out said method

Info

Publication number: WO2003051162A1
Application number: PCT/EP2002/014117
Authority: WO
Inventors: Carlo Rosso
Original assignee: Carlo Rosso
Priority date: 2001-12-18
Filing date: 2002-12-12
Publication date: 2003-06-26
Also published as: ITTO20011179A0; AU2002358684A1; ITTO20011179A1

Abstract

The present invention relates to an improved method of cutting tomatoes or other fruit and vegetable products into segments as a preliminary step to a dehydration process, more particularly a partial dehydration process. The method comprises making a longitudinal cut in the external skin and the outermost flesh portion in each segment, so as to assist in drying. The invention also discloses an apparatus for carrying out said method, in which the fruit and vegetable products, placed in suitable receptacles, are pushed against a set of blades comprising blades for the division into segments and blades for cutting the outermost portion.

Description

METHOD OF PREPARING FRUIT AND VEGETABLE PRODUCTS TO BE DEHYDRATED, AND APPARATUS FOR CARRYING OUT SAID METHOD

The present invention relates to a method of preparing fruit and vegetable products to be dehydrated, and to an apparatus for carrying out said method.

More particularly, the method of the invention can be advantageously employed for cutting tomatoes, to be partly dehydrated, into segments.

Moreover, the present invention concerns an apparatus capable of cutting the fruit and vegetable products into segments, according to the above method.

A method of preparing partly dehydrated or "semi-dried" tomatoes is already known, said method being disclosed for instance in French patent No. 2,757,020.

A partial dehydration of the tomatoes is to be effected, in such a manner that the final product retains a water content of about 30 to 35%. Indeed, the wholly dehydrated product loses its taste and the original colour: it is characterised by a brownish colour, it is saltier than the fresh product, and usually it is to be submitted to a readaptation process, e. g. a rehydration process, to recover the organoleptic characteristics of the fresh product. "Semi-dried" tomatoes have instead an accentuated red colour, not too salty a taste and a flesh retaining its original consistency, and in all respects they are a finished product, ready for use.

To prepare "semi-dried" tomatoes, it is first necessary to choose calibrated tomatoes (65 to 85 mm in diameter), with a high ripening degree, a consistency as high as possible, a sugar content corresponding to a Brix degree of 5.5 to 6.5%.

The selected tomatoes are cut into segments and laid on grids with the skin in contact with the grid and the flesh up. Said grids are then stacked one above the other and, at the end of the working cycle, the grids are introduced into a heating chamber, where they are left until the water content of the tomatoes decreases down to 30 to 35%.

Subsequently, the tomatoes are dressed with oil and herbs and put into containers. Thus, a long-life product is obtained, ready for use without need for any other preparation.

The main problem related with the process of partly dehydrating tomatoes, or possibly other fruit and vegetable products, concerns the drying phase, during which all main organoleptic properties of the fresh product are to be retained.

The method of the invention and the apparatus carrying out the method allow attaining a perfect drying of the product.

Moreover, to obtain a high quality product, it is essential that the tomato segments be laid with the skin down, in contact with the grid, and the flesh up.

The above and other objects of the invention are achieved by a method of cutting tomatoes into segments and by an apparatus carrying out said method, as claimed in the appended claims.

The method according to the invention comprises making a longitudinal cut of the external skin in each segment, the cut being sufficiently deep to favour water exit and product drying during the subsequent dehydration step.

To carry out said method, the apparatus according to the invention uses a set of blades against which the product to be cut is pressed, said blade set comprising two different kinds of blades: on the one hand, slicing blades, allowing dividing the product into segments; on the other hand, incision blades, allowing cutting the skin and the outermost flesh portion of the fruit or vegetable product. Advantageously, the apparatus according to the invention is characterised by the provision, below the blade set, of a suitably shaped grid, arranged to receive the divided and cut segments. Thus, the segments fall, immediately upon cutting, onto the grid already in the proper position, that is with the skin in contact with the grid and the flesh up. The grid can be removed and put into the heating chamber without requiring a step of manual positioning of the segments. An exemplary embodiment of the present invention will be better disclosed with reference to the accompanying drawings, in which:

- Fig. 1 is a perspective view of the tomato cutting apparatus according to the invention; - Fig. 2 is a top view of the tomato positioning plate shown in Fig.

1;

- Fig. 3 is a side view of one of the grids used in the apparatus shown in Fig. 1;

- Fig. 4 is a top view of the blade set used in the apparatus shown in Fig. 1 ;

- Fig. 5 is a cross-sectional view, taken along line A-A, of the blade set shown in Fig. 4;

- Fig. 6 is a side view of one of the cylinders used in the apparatus shown in Fig. 1 to push the tomatoes against the blades; - Fig. 7 is a plan view of the cylinder shown in Fig. 6;

- Fig. 8 shows a tomato cut by the apparatus according to the invention.

Referring to Figs. 1 and 2, there is shown an apparatus, generally denoted by reference numeral 1, capable of cutting the tomatoes in accordance with the method of the invention. Apparatus 1 comprises a substantially rectangular lower frame 5 resting on four legs 7. Four vertical uprights 9, parallel to each other and perpendicular to said frame 5, project from frame 5 and bear an upper frame 11, parallel to and having substantially the same shape and size as lower frame 5.

Frame 5 has mounted thereon a plate 15 made of polypropylene, in which a plurality of cylindrical receptacles 17 are provided to receive the tomatoes to be cut. In the embodiment shown, a matrix of 7x8 receptacles, i.e. fifty-six receptacles 17, has been provided, but such number can be varied depending on the needs.

A set of stationary blades, including both slicing blades and incision blades, is provided in each receptacle 17. The receptacles will be disclosed in more detail hereinbelow.

A moving plate is mounted between upper frame 11 and lower frame 5 and it is slidable along side guides 21 between a raised position corresponding to the level of upper frame 1 1 and a lowered position, in contact with plate 15.

Parallel, downwards extending solid cylinders 23, the function of which will be disclosed in detail hereinbelow, are secured to moving plate 19, said cylinders being as many as receptacles 17 below and being axially aligned therewith. Thanks to the provision of a central pneumatic piston, not shown in the drawing and arranged above upper frame 11 , plate 19 can be lowered along guides 21 until it rests onto plate 15 below. Thus, solid cylinders 23 push the tomatoes present in receptacles 17 against the blade sets below, causing the division into segments and the cutting of the external skin of each segment.

To prevent possible accidents to the operators, moving plate 19 can be lowered along guides 21 only when apparatus 1 is wholly closed. To this aim, four walls 27, 29 made of transparent material, e. g. plexiglas, are provided between lower frame 5 and upper frame 11. Side walls 27 are fixedly mounted onto uprights 9, between frames 5, 11. On the contrary, front walls 29 are slidable along uprights 9, between upper frame 11 and lower frame 5, so as to allow the operators to place the tomatoes into receptacles 17. When all of the tomatoes have been placed into respective receptacles 17, front walls 29 are lowered until they actuate sensors 30 on lower frame 5. When sensors 30 indicate that walls 29 have been wholly lowered and apparatus 1 is wholly closed, moving plate 19 may be lowered by operating control pushbuttons 31a, 31b. As a further safety provision, the pneumatic piston causing lowering of plate 19 is operated only if both pushbuttons 31a, 31b are simultaneously pressed at both sides of the apparatus. Advantageously, walls 27, 29 are made of plexiglas, so as to allow the operators to watch at the cutting operation and to stop the apparatus in case of malfunctioning.

A pair of rails 26 parallel to frame 5 is provided beneath frame

5, and a shaped grid 25 slides like a drawer on said rails. Tomato segments, divided and cut, fall down along the walls of receptacles

17 and become deposited on grid 25 due to the lowering of plate 19 and of the respective solid cylinders 23.

As better shown in Fig. 3, grid 25 is shaped so that to form, in correspondence with receptacles 17 of plate 15, a set of tapered portions 39 for receiving the tomato segments.

Thus, the segments are naturally arranged in tapered portions 39, with the skin in contact with grid 25 and the flesh up, thereby forming a sort of "flower".

Turning back to Fig. 1 , grid 25 can be made to slide along rails 26 until it is completely drawn out from below frame 5. The, grid 25 can be removed and, with the tomato segments divided, cut and properly positioned, it can be directly stacked with other similar grids into a suitable refrigerator, before being brought into the heating chamber. Figs. 4 and 5 depict receptacles 17 and the blade sets located therein in greater detail.

As shown in Fig. 4, receptacle 17 is a hollow cylinder 33 of stainless steel, such that an outer surface 33e and an inner surface 33i of such cylinder can be defined. The set of radial blades, comprising two or more slicing blades 35 and two or more incision blades 37, is located inside cylinder 33.

Slicing blades 35 begin at inner surface 33i of hollow cylinder 33 and radially extend up to the centre of said cylinder 33. On the contrary, incision blades 37 radially project from inner surface 33i of cylinder 33, but they end before the centre of said cylinder 33 and extend towards the centre of cylinder 33 by a length strictly shorter than the cylinder radius. Thus, said blades 37 cut the skin and the outer portion of the flesh of the tomato, without completely cutting the tomato.

As highlighted in Fig. 5, slicing blades 35 advantageously have the shape of rectangular trapeziums with their major bases adjacent to surface 33i and the oblique side up: thus, the whole of blades 35 form a receptacle where the tomato is kept stationary while awaiting to be sliced. Moreover, the slicing progress from the external surface until the centre of the tomato while the tomato falls down through cylinders 33 ensures a sharp cut, and the tomato is not squeezed. Still with reference to Fig. 5, also incision blades 37 have the shape of rectangular trapeziums, yet with their major bases down and the oblique side up, so that cutting starts at the tomato skin and gradually proceeds inside the flesh.

Incision blades 37 are secured to inner wall 33i of cylinder 33 at such a level that skin cutting starts when the tomato has been already divided into segments, that is, at a depth along cylinder 33 corresponding to a location where trapezoidal blades 35 already have reached the centre of cylinder 33.

In the embodiment shown, the blade set comprises eight slicing blades 35 and as many incision blades 37. The number of blades can be varied depending on the needs.

Inner surface 33i of cylinder 33 may be provided with a set of vertical slots, where slicing blades 35 and incision blades 37, the number of which varies depending on the needs, may be inserted. In order to obtain a high quality product, the tomato is preferably divided into six or eight segments, by employing therefore six slicing blades 35 and six incision blades 37 or eight slicing blades 35 and eight incision blades 37. Figs. 6 and 7 show one of cylinders 23 mounted on the upper plate 19, which cylinders, when being lowered, push the tomatoes against blades 35, 37.

Said solid cylinders 23 have slots 39, 41 in correspondence with blades 35, 37 of respective receptacles 17 below. Clearly, slots 39 corresponding to slicing blades 35 begin at the external surface of solid cylinder 23 and extend up to the centre of said cylinder 23. Slots 41 corresponding to incision blades 37 also begin at the external surface of a cylinder 23, but they do not extend up to the centre of said cylinder 23. Instead, they have a somewhat longer length than the corresponding incision blades 37.

If it is desired to vary, depending on the needs, the number of blades 35, 37 provided inside cylinder 33, cylinders 23 will be advantageously removably mounted onto plate 19 which in turn will have as many circular holes. Thus, the cylinders could be chosen every time with a number of slots 39, 41 corresponding with the number of blades 35, 37 below.

Fig. 8 shows a tomato 43 cut according to the method of the invention and by using apparatus 1 shown in the previous Figures. - Tomato 43 is cut into eight identical and separate segments 43a. Each segment 43a has one cut 43b in the skin and the outermost flesh portion and, preferably, the cut depth is not lower than 10 mm.

Thanks to the peculiar shape of grid 25, segments 43a are located into tapered portion 39 in a flower-like arrangement, with the skin in contact with the grid and the flesh up. The segments are therefore already in the proper position to be submitted to the dehydration process.

Claims

Patent claims

1. A method of cutting fruit and vegetable products, in particular tomatoes (43), into segments (43a) to be submitted to a dehydration process, characterised in that at least one longitudinal cut (43b) is made on the side of the skin for each segment (43a) , to increase the water evaporation surface during the subsequent dehydration step.

2. A method as claimed in claim 1 , characterised in that said cut (43b) has a depth not lower than 10 mm.

3. A method as claimed in claim 2, characterised in that a single cut is made for each segment.

4. A method as claimed in claim 3, characterised in that each tomato is cut into six or eight segments, each having one cut.

5. An apparatus (1) for cutting fruit and vegetable products (43) into segments (43a), comprising:

- a lower horizontal frame (5) supported by a plurality of legs (7) ;

- a stationary plate (15) mounted on said lower frame (5) and provided with a plurality of cylindrical bored receptacles ( 17) for said products (43); - a plurality of parallel, upwards projecting uprights (9), secured to said lower frame (5b) ;

- a horizontal upper frame (11), carried by said uprights (9);

- a first plurality of blades radially arranged within said cylindrical receptacles (17), for dividing the products into segments; - a second plurality of blades radially arranged within said cylindrical receptacles (17), for making at least one cut into each said segment;

- a plate (19), slidable between said lower and upper frames and parallel to said lower (5) and upper (11) frames, which plate is equipped with a set of parallel and downwards directed solid cylinders (23) having longitudinal slots (39, 41), said cylinders being as many as said receptacles (17) and being axiaHy aligned therewith so that, when the slidable plate (19) is lowered against the stationary plate (15), said solid cylinders penetrate into said receptacles (17) and said first and second blades penetrate into said slots; - a plurality of guides (21) parallel to said uprights (9), along which guides the slidable plate (19) may slide until contacting either the lower plate (15) or the upper frame (1 1).

6. An apparatus (1) as claimed in claim 5, characterised in that four walls (27, 29) are provided on the uprights (9) between the lower frame (5) and the upper frame (11), at least one wall (29) being vertically slidable along the uprights (9) between the lower and upper frames (5, 11) to allow access to the area between said two frames.

7. An apparatus (1) as claimed in claim 6, characterised in that one or more sensors (30) are provided on the lower frame (5) for each slidable wall (29), to signal whether said wall (29) is blocked against said frame (5) and to enable means for lowering the slidable plate (19).

8. An apparatus (1) as claimed in claim 6, characterised in that said walls (27, 29) are made of transparent material, in particular plexiglas.

9. An apparatus (1) as claimed in claim 5, characterised in that a grid (25) is located below the lower frame (5), which grid can be drawn out by making it slide on a pair of rails (26).

10. An apparatus (1) as claimed in claim 9, characterised in that said grid (25) has a set of tapered portions (39), of which the number is the same as that of the receptacles (17) provided in said stationary plate (15), said tapered portions being arranged so as to be axially aligned with said receptacles (17) when the grid (25) is completely retracted below said stationary plate (15).

11. An apparatus (1) as claimed in claim 5, characterised in that each receptacle (17) for the fruit and vegetable products (43) comprises a hollow cylinder (33) where a set of radial blades (35, 37) is provided.

12. An apparatus (1) as claimed in claim 11 , characterised in that said blade set comprises at least two slicing blades (35) that start from the inner surface (33i) of the cylinder (33) and meet at the centre of said cylinder (33), and at least two incision blades (37) that start from the inner surface (33i) of the cylinder (33) and extend towards the centre of said cylinder (33) over a length strictly shorter than the cylinder radius.

13. An apparatus (1) as claimed in claim 12, characterised in that the slicing blades (35) have the shape of rectangular trapeziums and are arranged with their major bases against the inner surface (33i) of the cylinder (33) and their oblique sides up.

14. An apparatus (1) as claimed in claim 12, characterised in that the incision blades (37) have the-ϊ shape of rectangular trapeziums and are arranged with their major bases down and their oblique sides (33) facing up.

15. An apparatus (1) as claimed in claim 12, characterised in that the incision blades (37) are secured to the inner surface (33i) of said hollow cylinder (33) at such a level that skin cutting of the product to be cut starts when the product has been already divided into segments by the slicing blades (35).

16. An apparatus (1) as claimed in claim 12, characterised in that said blade set comprises six or eight slicing blades (35) and six or eight incision blades (37).

17. An apparatus (1) as claimed in claim 12, characterised in that the inner surface (33i) of the hollow cylinder (33) has a plurality of slots into which the slicing blades (35) and the incision blades (37) may be inserted, according to the needs.

18. An apparatus (1) as claimed in claim 17, characterised in that said solid cylinders (23) mounted onto the slidable upper plate (19) are removable and can be replaced, as the case may be, by other cylinders (33) having as many slots (39, 41) as are the blades (35, 37) mounted in the corresponding slots of the hollow cylinders' (33) below.