Ethylene adsorption for the control of ripening of fruit and vegetables

0001The present invention relates to a method for Inhibition of the ripening process of fruits, an arrangement for Inhibition of the ripening process and a process for Manufacture of the device.

0002Today's consumer society is accustomed possible year-round all kinds of beverages, or edibles, as in particular fresh products such as fruit, vegetables, etc., enjoy and be able to consume.

0003Especially fruit, which in our latitudes summer and autumn is harvested, it must be stored in accordance be so even in the winter or spring of the last year Harvested fruit perfectly ripe or Essreife having. On the one hand this can be achieved by harvesting the fruit at not yet reached full maturity, but more crucially the correct storage, at wherein the maturation is inhibited as possible. It is on the one hand a bearing atmosphere enriched selected nitrogen / carbon dioxide content in the air, and If the storage at low temperatures in the range of about 0 - 5 ° C.

0004was further recognized that ethene is the cause of the Fruit ripening and the fruit ripening process by in whose presence the ripening and shrinkage strongly is affected. According to recently Warehouses with vents fitted to the the Fruit delivered ethene to constantly remove.

0005Well, the mentioned ventilation in accordance furnished warehouses possible but difficult for example during transport and during storage in Stock cellars and the like. In addition, all outlined above Measures very energy-intensive and expensive.

0006Because ethene causally linked to the fruit ripening is modern warehouse and transport processes on a need extensive exclusion of ethene from the storage atmosphere by aiming to suppress the Ethenwirkung. Thus, the fruit ripening can be delayed and the durability the fruit and the fruit be extended. correspondingly the 134,022 proposed in EP 1, a using hydrophobic zeolite as an adsorbent to ethene exclude from the storage atmosphere or to the suppress Etheneinwirkung to the fruit maturity delay. It is proposed an adsorbent to use consisting of a hydrophobic zeolite and at least one binder. However, the EP 1 remains 134 022 a proposal guilty in any form of hydrophobic zeolite can be used, which ultimately well, is also the reason why hydrophobic zeolite to today for the inhibition of the ripening process does not use have found.

0007It is therefore an object of the present invention propose practical measures to the ripening process, especially of fruits, effective to inhibit or delay.

0008According to the invention the object is by means of a Method according to the wording of claim 1 and by means of an arrangement according to the wording dissolved claim 3.

0009It is proposed that the inhibition of the ripening process, in particular of fruit, an arrangement as in particular a film, a strip of paper or the like. containing zeolite is disposed in the vicinity of the fruit which, in the Is able to adsorb ethene.

0010In the arrangement may be a film based on a polymer, a paper sheet, a cardboard or a box or a box-like container etc. act which is capable of ethene or ethylene to absorb to the ripening process and the shrinkage of to prevent fruit.

0011responsible for Ethenadsorption is a hydrophobic ethenaufnahmefähiges molecular sieve or zeolite, at which it is a highly porous aluminosilicate concerns such as in EP 1134022 proposed with a network of well-defined Pores. In this case, the molecular sieve in either the film or be incorporated in the paper or the foil or the paper has a coating with the Ethenaufnahmefähigen Molecular sieve.

0012For the production of the inventive arrangement or for the foil or the paper, the zeolite or the Aluminosilicate having defined pores in a Polymer melt in the sense of a filler or additive be admixed, whereupon Subsequently, the film is extruded. It must be ensured that the ready-made film for ethene is permeable. Or however, the zeolite or the aluminum silicate is in the Production of paper the aqueous pulp, in turn, in the sense of an additive added in order then the Pulp according to conventional paper making process further process.

0013However, it is also possible for the hydrophobic zeolite in The meaning of a coating on a polymeric film or apply or aufzuwalzen paper aufzupressen, etc. This may for example in the form of an aqueous dispersion done.

0014As binders for this purpose are, for example silanes or siloxanes, which in this case, the evaporation of Water can be avoided, which lower Coating temperatures allowed.

0015The coating of a polymer film can be similar to Method of producing a siliconized foil done.

0016As long as the special paper or film, containing the Molecular sieve or coated with the molecular sieve, in Contact or is disposed in the vicinity of fruit, fruit can also be stored at room temperature in good quality. The foil or paper, for example, for laying of storage racks, storage drawers, for lining Transport boxes, etc. can be used. For the inhibition of It is further advantageous process when the inventively proposed arrangement or films or Papers to be stored in the vicinity of the fruit or of the to transporting fruits are arranged. correspondingly it may also be advantageous if one side of the Film or of the paper or of the coating opposite side of the film or of the paper Adhesive is applied, which before disuse of the film covered with a siliconized paper or the foil is to ensure that the glue does not dry until use. In use, the siliconized film was removed and the the ethene receptive molecular sieve-containing film or the paper may, for example, on a wall, similar to a wallpaper, in a transport container, on a Storage grid, are arranged, etc., through the exposed glue the foil or paper can be arranged without slipping. By arranging the inventively proposed arrangement considerably cooling energy can be saved, and possibly dispense with the use of inert gas will.

0017As already mentioned above, it is the zeolite highly porous crystalline aluminosilicate having a high specific surface area. The ratio of SiO₂ to Al₂O₃may be from about 10 - vary 1000th The greater this Ratio, the more hydrophobic is the surface of the Zeolite. The self-adjusting pore systems Pore ​​openings can be one, two or three dimensional be, with pore openings of about 0.3 x 0.3 to 0.8 x 0.8 nm.

0018For a better understanding of the invention is hereinafter with reference to the attached figures, each one For example, a possible layer structure inventive arrangement described.

0019They show:<dl tsize="6"><dt>Fig. 1</dt><dd>an inventive arrangement in which the Ethenadsorber in the film or in paper is arranged integrated;</dd><dt>FIG. 2</dt><dd>schematically a layer structure of a inventive arrangement with the Ethenadsorber as a coating disposed on a foil or a paper.</dd></dl>

0020Figure 1 shows in section schematically illustrating the construction of a inventive arrangement comprising a film or a paper 1 containing the ethene receptive Molecular sieve. On one side of the film or of the paper 1 is arranged an adhesive third As such, any can conventional adhesive can be used which are suitable for bonding a film or paper on a flat surface, such as cardboard, wood, masonry, Gypsum, etc. One example would be a glue here Melamine resin. The adhesive is covered finally 5. by a siliconized cover Attaching the Adhesive is always optional.

0021For the production of the film or of the paper 1, a hydrophobic zeolite in the polymer or paper matrix built-in. In this case, the zeolite in a polymer melt, such as molten polyethylene, for Film-making polyester, polyamide, Polypropylene, etc. for the purposes of an additive or Filler or a reinforcing agent in the order of magnitude of about 5-30% by weight are incorporated, and. then the melt in accordance with the Plastics industry conventional processes into films are processed. In the case of using a Paper pulp is again analogous to the zeolite in the Magnitude 5 - 30 wt% in the pulp. incorporated, and then this according to common Papermaking used for further processing.

0022The production of the inventive arrangement, but also be achieved by a polymer film or a Paper is coated with the molecular sieve. A so produced arrangement is shown schematically in section in Figure 2 shown. On a polymer film or a paper 13 applied is a coating 11, including the ethenadsorbierende molecular sieve. The coating of Paper or the film can be obtained by applying an aqueous Dispersion containing the zeolite occur. The Coating, by spraying, pressing, rolling, done etc.. After application of the coating is then the water is removed. The coating may but the same methods are carried out analogously as the Siliconization of films, which has long been known.

0023After coating, the film is again optional optionally on the opposite, the coating Side provided with an adhesive 3, in which it is turn to an a eneral usual for bonding Foil or paper used adhesive can act. Finally, the adhesive is again before use of the film or the paper with a siliconized liner 5 provided.

0024For the use of the inventive arrangement will now be initially the siliconized cover 5 removed and the Foil or paper by the adhesive, for example, in the sense of wallpaper is mounted on a wall or but can be a wooden frame are lined, on or in which the fruit to be stored is placed. It is also possible transport boxes inside the undress inventive film or paper.

0025For the manufacture of the film or coating of the film or paper, for example, zeolite types with a SiO₂/ Al₂O₃Ratio are used by> 10 - ca. 1000. Examples include the ZSM-5 type, for example, to buy as Zeocat PZ-2/400 from Zeochem AG, Uetikon, Switzerland, which a SiO₂/ Al₂O₃comprising ratio of 400th This Zeolite belongs to the MFI structure type, and has a three-dimensional pore system with pore openings of about 050 x 0.55 and 0.55 x 0.55 nm.

0026Another example is the zeolite beta with a SiO₂/ Al₂O₃Ratio of 20, for example, available as Zeocat PB Zeochem AG, Uetikon, Switzerland. This zeolite part of the structure type BEA, and has a three-dimensional Pore ​​system with pore openings of approximately 0.65 x 0.75 and 0.55 x 0.55 nm.

0027Again another example is the zeolite of type Mordenite having a SiO₂/ Al₂O₃Ratio of 25, for example, available as Zeocat FM-8 / 25H Zeochem AG, Uetikon, Switzerland. This zeolite is part of the structure type MOR and has essentially a one-dimensional pore system with pore openings of approximately 0.65 x 0.70 nm.

0028Finally, as a further example, mention may be made of USY type zeolite with a SiO₂/ Al₂O₃Ratio of 60, eg available as AkZeo-765 from Akzo, Holland. This zeolite is part of the structural type FAU and has a three-dimensional pore system with pore openings of about 0.75 x 0.75 nm.

0029It goes without saying that it is in the specified SiO₂/ Al₂O₃Ratios only examples concerns, and that said all this zeolite Ratio can vary within wide limits. The enumeration the aforementioned zeolites has no final Character. It can basically zeolites with a SiO₂/ Al₂O₃Ratio that is greater than 10 is used, will. In addition, all zeolites mentioned above with Silver ions are impregnated.

0030The ion exchange for the impregnation is carried out in a known to those skilled type, usually in a aqueous suspension is worked. The introduced Silver ions displace the existing mobile cations the zeolite lattice. The ion-exchange factor can be in moving range of 5 to 100%. Such treated Zeolite has still the property of ethene to absorb. In addition, such a zeolite bactericidal properties. This not only the Aging process of the fruit slows, but also Decay processes are inhibited, which by Microorganisms are induced.

0031Finally, it should be mentioned in addition that obvious use other materials may be, which are capable of adsorbing ethene. In principle is essential for the present invention the use of an array of inhibiting a Ripening process of fruit in particular, which is capable of adsorb or surrounding the fruit from the ethene to withdraw atmosphere.