WO2008026926A1

WO2008026926A1 - Method for decorating cheese

Info

Publication number: WO2008026926A1
Application number: PCT/NL2007/050428
Authority: WO
Inventors: Corstiaan Hooft; Philip Schippers
Original assignee: Friesland Brands B.V.
Priority date: 2006-08-30
Filing date: 2007-08-29
Publication date: 2008-03-06
Also published as: NL1032392C2

Abstract

A method for decorating cheese (1), comprising the successive steps of - heating a flexible tampon ot balloon(5); - transferring an image (3), comprising adhesive and ink, from a carrier (2) to the heated flexible tampon or balloon; - contacting the tampon ot balloon provided with the image, under pressure, with the cheese, whereby the tampon or baloon deforms; and - removing the tampon or balloon, whereby the image remains behind on the cheese.

Description

Method for decorating cheese.

The invention relates to a method for decorating cheese. As soon as cheeses, and in particular natural cheeses of the hard and semi-hard type, specifically those cheeses in which, during the ripening stage, formation of gas will occur, leave the brine bath, they are typically provided with a so-called support banderol. As a rule, this banderol is provided around the cheese together with a first layer of cheese plastic, and gives support to the still soft cheese. This support is in particular necessary for holding the cheese in shape when gas formation occurs in the ripening stage. Then, the cheese is stored for the ripening process. During this ripening, which, depending on the type of cheese and the desired age, lasts a specific period of time, maintenance on the cheese takes place. During this maintenance, the cheese surface is provided a number of times with a so-called cheese plastic. This cheese plastic typically consists of a plastic dispersion; for instance a polyvinyl acetate copolymer, such as a copolymer of polyvinyl acetate and the dibutyl ester of maleic acid.

It is often also desirable to decorate the cheese. One manner of providing whole semi-hard and hard cheeses with a decoration is providing a silk tissue label. The label of silk tissue paper is printed for the purpose of decoration, and is applied during the treatment with cheese plastic and adheres with the cheese plastic to the cheese. For cheese types wherein formation of gas occurs, such as cheeses of the Maasdam or Emmertaler type, it is of importance that the label is provided before the cheese begins to bulge. The fact is that when the label is provided on a convex surface, this leads to the formation of creases. This is undesired, not only from an aesthetic point of view, but also, air can be entrapped so that, for instance, mould can develop. If the label is provided together with the cheese plastic on a flat cheese, the label becomes, as it were, one with the flexible cheese plastic and forms the decoration while the cheese bulges. It is also possible to provide a printed banderol during one of the times the cheese maintenanced. This banderol is typically made of silk tissue paper and is wound around the cheese from the roll. By carrying out this operation during maintenance with cheese plastic, a good adhesion of the banderol to the cheese plastic and the cheese is obtained.

In particular cases, the cheese can also be provided with a printed banderol directly after the brining bath. This is applied instead of the earlier mentioned support banderol.

In a number of cases, the cheese is provided with a paraffin layer just before delivery. This paraffin layer seals the cheese from the environment (atmosphere) and prevents further dehydration and/or bulging of the cheese.

A drawback of the above-mentioned known processes is that the cheese is provided with a decoration well before delivery and therefore already obtains a client specific destination in an early stage. This limits the flexibility in the production process. A delay during the fermentation process, or a storage effect during ripening can lead to a particular delivery not being satisfied, or that high costs must be made to have the respective delivery be carried out.

An additional drawback of the processes known from the state of the art is that through the application of the paraffin layer, the image of the decoration becomes faint. As a result, the color strength decreases. Also the application of a decoration with only the cheese plastic (therefore without paraffin layer) can compromise the color strength of the image of the decoration. Another manner of decorating comprises the application of an adhesive label on the outside of the cheese as known from EP-A-O 945 354. In this case too, the surface of the cheese should be flat as otherwise formation of creases would occur. In addition, the emotional value, at least the appreciation of the customer for such a glued-on label appears not as great as that for a more integrated decoration. Prom WO-A-83/01051, a method is known for melting labels into the paraffin layer of a cheese. This method can, however, only be utilized if a paraffin layer is present. Furthermore, when applying the described labels on a convex surface, creases will be formed. These creases lead to a carelessly finished product.

The cheese surface can further be directly printed with, for instance, an inkjet or tampon printing technique. With tampon printing, one color (ink), or a simple combination of several colors (crude screen) which is indirectly transferred by a tampon on the product to be decorated is utilized. As the tampon is flexible, double-curved surfaces (convex or concave) can be printed. The drawback of tampon printing and inkjet printing is that the number of colors to be used is limited in view of food safety and that the resulting image is not high-grade.

An object of the present invention is to provide a method for decorating cheese that offers a solution for one or more of the above-mentioned drawbacks from the state of the art.

It has been found that this object can be realized with the method according to the present invention, wherein an image is transferred from a carrier to a cheese by means of a tampon or balloon. Therefore, the present invention relates to a method for printing a cheese, comprising the successive steps of:

- heating a flexible tampon or balloon;

• transferring an image that comprises adhesive, binders and ink, from a carrier to the heated flexible tampon or balloon; - contacting the tampon or balloon provided with the image, under pressure, with the cheese, whereby the tampon or balloon deforms;

- removing the tampon or balloon, whereby the image remains behind on the cheese.

An important advantage of the method according to the invention is that a ready printed image, a so-called transfer, is transferred to the product, while with the inkjet and tampon printing techniques, ink is transferred to the product.

Another great advantage of this method is that the cheese can be provided with an image at an advanced stage in the production process, thereby increasing the flexibility in the production process and limiting failure costs for preventing short deliveries.

The image is flexible because it is provided without a carrier. The image is a complex comprising inks and adhesive and binder and can be stretched to a factor 2 — 3. As a result, cheese having or not having a convex surface, such as convex cheese, can be decorated without creases being formed in the decoration.

A method wherein an image is provided on an object without carrier, such as ceramic crockery, for that matter, is already known from EP-A-O 251 780. In this publication, the printing of cheeses is not suggested. As further background for the existence per se of techniques for transferring an image to an object, reference is made to US 4,392,905 and US 4,511,425. like EP-A-O 251 780, these documents do not relate to printing cheese.

In fact, much of the method described in EP-A-O 251 780 can be used for decorating cheese, for which reason this publication is included in the present description for the description of the technique. It is however noted that cheese is an entirely different substrate from what is described in EP A-0251 780: here, a foodstuff is decorated.

Cheese is a foodstuff so that for printing, specific requirements are set with respect to food safety. Another specific element of the invention is that with the manner of decoration according to the invention, a flexible decor can be provided. This has as an advantage that as a result, the image can be provided without creases on a convex surface. A multicoloured image can thus be provided without creases on a convex cheese surface. Each cheese is different as to shape and surface and precisely therefore the method according to the invention is so powerful: the flexibility of the transfer, combined with the flexibility of the tampon or balloon, allow for the provision of an image without creases on any cheese. Further, it is of importance that cheese is a living" product; after the image has been provided, the cheese can change shape. With this, another advantage according to the invention is obtained: the image (the complex of inks and binder) is flexible and can grow and shrink along with the cheese.

The use of a transfer which is transferred through heat to the tampon or balloon to non-heated cheese is not suggested in EP-A-0251 780. The image is provided on the cheese in that, in the process of decoration, the image is taken over from a carrier by a flexible and heated tampon or balloon. This tampon or balloon carries the image to a surface of the cheese and, under pressure, the image is adhered to the cheese surface. Preferably, the image is provided on the top or bottom of the cheese, i.e. a flattened side of the whole cheese. An optional bulge or small irregularities are compensated by the flexibility of the image-carrying tampon or balloon. In addition, the flexibility of the tampon or balloon also ensures the decoration to be provided on the cheese in a neat manner and without air inclusions.

It is preferred that the tampon or balloon be made from a rubber, such as, for instance and preferably, a silicon rubber. A tampon is solid and finds its flexibility in the density of the rubber that is denser towards the core. Hence, the outside is softer than the inside. The balloon should be conceived as a thick slice of rubber which is stretched on a metal holder while, during the process, the space between the holder and the rubber slice can be filled with heated or non-heated air. In the process of applying, the balloon can be controlled as to hardness and shape by filling the cavity with heated or non- heated compressed air.

When a balloon is used for transferring the image from carrier to the cheese surface, use is made of the flexibility of the surface of the balloon and the possibility of varying the form retaining property in different stages of pressing-on through internal pressure differences.

According to the method of the invention, the tampon or balloon is heated before the image is transferred from the carrier to the tampon or balloon. The tampon or balloon is heated for, for instance, 15 — 30 s to a temperature or 60 - 150⁰C, preferably 115 - 125⁰C. The core temperature is approximately 100 - 110⁰C; the temperature of the surface is preferably approximately 120 ⁰C. The effect of the heating is twofold. On the one side, the outside is heated, so that the transfer adheres better to the tampon or balloon than to the carrier material and is therefore taken over by the surface of the tampon or balloon. On the other side, the rubber is made flexible to thus ensure that when bringing together the tampon or balloon with the transfer adhering thereto, owing to its flexibility, the transfer can be unwound onto the (convex) surface of the cheese. As the tampon or balloon is heated, the surface is flexible and an equal pressure can be applied to the entire contact surface of cheese and tampon or balloon, while, as the cheese has a low temperature, the transfer melts together with the surface of the cheese. The temperatures can simply be determined by experiment by the skilled person. As a rule, a temperature of less than 60 - 7O⁰C is not desirable, because then, the tampon cannot break the adhesion between transfer and carrier and furthermore obtains an insufficiently sticky surface so that the transfer does not adhere to the tampon or balloon. As a rule, a temperature of over 150⁰C is not desirable either, because then, the rubber, such as silicon rubber, begins to show signs of melting and burning. The tampon or balloon can be heated by means of, for instance, infrared radiation. This has as an advantage that the heating step proceeds rapidly and that energy loss is minimal, because the energy is only used at the moment of heating and not in other stages of the process.

The image is transferred under pressure from the carrier to the tampon or balloon and from the tampon or balloon to the cheese. The pressure at which the tampon or balloon is pressed on the carrier or the cheese is greater than atmospheric pressure and is, preferably, 1.2 — 3 bara, and more preferably 1.5 - 2 bara. An increased pressure contributes to uniform pressing on of the entire surface of the image on the cheese and, hence, to a strongest possible adherence of the transfer to the cheese. Here, it once more applies, for that matter, that the pressures, depending on the cheese to be decorated, can simply be determined by experiment by the skilled person.

The image is built up from a multilayer structure, wherein, on a wax-coated paper (carrier) successively, a so-called release layer, a layer with different colors and a cover layer are pressed. The release layer is suitably a wax-based varnish. Through heat, the connection to the wax-coated carrier is broken and upon solidification on the cheese, adherence to the surface takes place through cross-linking with the cheese coating present on the cheese, or melting with the paraffin present on the cheese. The inks used are diluted on the basis of solvents and through supply of temperature and destratification of air, the inks cure, while all solvents volatilize. The inks are solvent-based because of the necessary flexibility of the image. The cover layer is a type of varnish layer (a material derived from polyvinyl alcohol) which reacts under the influence of heat and becomes sticky through temperature increase. At a low temperature (< 60⁰C) the cover layer has a smooth, non-sticky surface. Without wishing to be bound to any theory, it is assumed that transferring the image according to the invention is based on differences in adhesive strength. Firstly, the adhesive strength between the carrier and the image is smaller than the adhesive strength between the image and the tampon or balloon. Secondly, the adhesive strength between the tampon or balloon and the image is smaller than the adhesive strength between the image and the cheese.

It is supposed that as the tampon or balloon is heated, the surface becomes slightly sticky and, upon contact, the transfer adheres to the tampon or balloon. The heated tampon or balloon melts the adhesive layer, as it were, which has a wax-like composition and ensures adhesion of transfer and carrier material in non-activated condition. Utilizing the wax layer activated by heat and the increased adhesive strength to tampon or balloon, the transfer with adhesive is removed from the carrier and thereupon applied to the cold surface of the cheese. Here, the adhesive power of the adhesive layer is used and, in that stage, under pressure of the cooling tampon or balloon, the transfer adheres better to the cheese surface than to the tampon or balloon, so that a decorated cheese is the end result. The specific composition of the substrate determines the composition of the transfer.

The decoration of the banderol at the circumference of the cheese can be maintained or be replaced by a decoration comparable to the one on the top surface of the cheese. The decoration is then taken over from the carrier material and transferred to the circumference of the cheese.

The image can be provided directly on the cheese but one can also choose to provide the transfer on the paraffin layer. Through the use of the properties of the paraffin layer which is provided over the cheese, the difference in adhesive strength can be optimally used. This means that the properties of the adhesion of the wax layer between transfer and carrier are utilized for, in the following stage, increasing the adhesion between transfer and paraffin (wax-like): the transfer and the paraffin melt together, as it were. Suitable inks for the method of the invention are solvent-based because of the necessary flexibility of the image. The inks are also known and suited for, inter alia, use on the skin.

Depending on the used inks, the image can obtain a mat character and hence contribute to a sense of authenticity. Conversely, through the use of different inks, also, additional color strength can be given to the image. With respect to the state of the art with the silk tissue labels, with this, more options for marketing are given.

The method of ^fhe invention will now be further elucidated by means of the non-limitative embodiment of Fig. 1. In operation, a ready cheese (1) provided or not provided with paraffin, is supplied on a track (9). The carrier material (2) is supplied in the form of, for instance, sheets and placed on a stack (4) in a stockroom.

The carrier material is provided with a print (3) which forms the actual image. Due to its composition, this print is flexible and has a good adhesion to the cheese plastic and/or to the paraffin.

The tampon or balloon (5) is suspended from a movable arm (8), such as a robot arm. With it, the tampon or balloon can be placed, in its position of rest, in the holder or pocket (6). This holder is provided with reflector heaters (7) with which the tampon or balloon can be heated for instance by infrared heating.

After heating, the process is continued by bringing the tampon or balloon above the transfer position (15). By pressing the tampon or balloon on the image, the image is taken over from the carrier material by the heated tampon or balloon. At that moment, the adhesive strength of the image with the tampon or balloon is greater than the adhesive strength of the image with the carrier material. As the tampon or balloon is flexibly deformable, it completely takes over the image and, as next step, the tampon or balloon can be positioned with the image above a prepared cheese. By moving the tampon or balloon downwards, owing to the defoπnability of the tampon or balloon, the image is unwound as it were on the surface of the cheese. Here, the adhesive strength of the image with the cheese is stronger than the adhesive strength of the image with the tampon or balloon. As soon as the image is pressed sufficiently fixedly on the cheese, the tampon or balloon is brought to its position of rest, and the conveyor belt advances one position, so that the printed cheese (11) can leave the machine. As an alternative for the images supplied on sheets, the images can also be supplied on a roll. The images (3) are then printed on a roll of carrier material (14). This roll is stretched in the machine on axle (12) and brought, via a guiding mark (16), to the proper position in the transfer position (15). At that position, the image as described hereinabove is taken over by the tampon or balloon. The roll of carrier material is wound up on axle (13).

Claims

1. Δ method for printing a cheese, comprising the successive steps of

- heating a flexible tampon or balloon;

- transferring an image, comprising adhesive and ink, from a carrier to the heated flexible tampon or balloon; - contacting the tampon or balloon provided with the image, under pressure, with the cheese, whereby the tampon or balloon deforms;

2. A method according to claim 1, wherein the image comprises an adhesive, binder and ink.

3. A method according to claim 2, wherein the adhesive is selected from wax-based varnish.

4. A method according to any one of the preceding claims, wherein the cheese is a gas forming cheese and has a convex surface upon decoration.

5. A method according to any one of the preceding claims, wherein the cheese is provided with a paraffin layer.

6. A method according to any one of the preceding claims, wherein the tampon or balloon is heated to 60 - 150⁰C and preferably to 115 - 125^βC

(preferably for 15 - 30 s).

7. A method according to any one of the preceding claims, wherein the tampon or balloon is heated by means of infrared radiation.

8. A method according to any one of the preceding claims, wherein the tampon or balloon is contacted with the carrier or the cheese under a pressure of 1.2 - 3, and preferably 1.5 - 2 bara.

9. A cheese decorated according to any one of the preceding claims.