WO2016005625A1

WO2016005625A1 - System and method for packaging dairy products

Info

Publication number: WO2016005625A1
Application number: PCT/ES2015/070331
Authority: WO
Inventors: Antonio Vera Prieto; Jorge Isern Jara
Original assignee: Antonio Vera Prieto
Priority date: 2014-07-10
Filing date: 2015-04-22
Publication date: 2016-01-14
Also published as: ES2523025A1; ES2523025B1

Abstract

The invention relates to a system and method for packaging dairy products, involving the effective substitution of the oxygen present in the dairy product by nitrogen, guaranteeing an optimal preservation. The system comprises: a pasteurisation unit connected to at least one homogeniser; first oxygen-nitrogen gas exchange means connected to the outlet of the homogeniser; and flow stabilising means between the first oxygen-nitrogen gas exchange means and at least one packaging unit linked to the outlet of the flow stablising means, said packaging unit comprising a leak-tight space that houses container-filling means and combustion means.

Description

DESCRIPTION

SYSTEM AND PROCEDURE FOR PACKAGING OF DAIRY PRODUCTS OBJECT OF THE INVENTION

The purpose of this application is to register a system and a procedure for packaging dairy products that incorporate notable innovations. More specifically, the invention proposes the development of a system and a method of packaging dairy products that includes the effective replacement of the oxygen present in the dairy product with nitrogen, which ensures optimum conservation.

BACKGROUND OF THE INVENTION

We are at a time when there is a high demand for food, growing day by day, of the greatest possible variety, in which the customer becomes more demanding in both quality and service. A food in growing demand is pasteurized milk, whose nutritional properties and health benefits are arousing great interest, resulting in increased demand in the dairy food sector. However, pasteurized milk as it is served by producers and wholesalers presents an important conservation problem, its short shelf life even in refreshments at relatively low storage temperatures, which complicates and increases the entire supply chain from packaging to points of sale. In a relatively short time the proliferation of microorganisms leads to a process of degradation of pasteurized milk that is no longer edible. Until now, given the characteristics of current packaging and its processes, the durability of fresh pasteurized milk is determined between 8 and 25 days. In addition, the presence of oxygen in pasteurized milk during packaging triggers a set of oxidation reactions which lead to the rapid deterioration of the milk, resulting in a messy product and with important changes in pH that make it unfit for consumption. . To extend the shelf life of milk, a thermal process known as "uperization" (UHT) is used, in which the milk is subjected to higher temperatures than traditional pasteurization, although for a shorter period of time. Thanks to "uperization," the number of microorganisms present in milk is greatly reduced and can be stored at room temperature for a period longer than simply pasteurized milk; However, this thermal process modifies the flavor and nutritional properties against pasteurized milk.

On the other hand, the use of inert gases in general and in particular of gaseous nitrogen in the food industry for food preservation is known. However, in the known preservation methods for dairy products such as milk, such as in EP2162021, the use of gaseous nitrogen does not allow an effective replacement of oxygen by nitrogen, whereby the remaining oxygen present during packaging contributes to the mess of milk. In this European application, a preservation method is mentioned that, in addition to not developing procedures and packaging systems applicable to dairy products, does not show that, for example, pasteurized milk significantly exceeds the conventional date of preferential consumption of conventional methods. DESCRIPTION OF THE INVENTION

The present invention has been developed in order to provide a dairy product packaging system and the procedure followed by it to solve the aforementioned drawbacks, also providing other additional advantages that will be apparent from the accompanying description. then.

It is therefore a first object of the invention to provide a dairy product packaging system comprising a pasteurization unit linked to at least one homogenizer, and additionally comprising first oxygen-nitrogen gas exchange means linked to the outlet of the homogenizer, presenting flow stabilization means between the first oxygen-nitrogen gas exchange means and at least one packaging unit associated with the output of the flow stabilization means, the packaging unit comprising a sealed space that houses means for the filling of containers and combustion means. Thanks to these characteristics, a dairy product packaging system is achieved in which the introduction of nitrogen into the dairy product occurs after pasteurization and homogenization, which prevents the return of more oxygen during the handling of the dairy product. On the other hand, the presence of combustion means at the point of packaging guarantees that any residual oxygen contained in the dairy product after the first oxygen-nitrogen gas exchange means is effectively removed from the dairy product. According to a further aspect of the present invention, the first oxygen-nitrogen gas exchange means preferably comprise at least one pressurized nitrogen injector in the dairy product, an outlet valve for oxygen from the dairy product and at least one stirrer. of the dairy product. Advantageously, the present packaging system may additionally comprise a second oxygen-nitrogen gas exchange means between the flow stabilization means and the packaging unit. The presence of a second oxygen-nitrogen gas exchange means ensures, if necessary, practically the non-presence of oxygen from the dairy product that reaches the packaging unit.

The second oxygen-nitrogen gas exchange means comprise an upright coil, the coil having at least one exhaust valve which is advantageously located in the upper or higher part of the coil. Thanks to this valve disposed in the upper part of the coil, the oxygen still present in the dairy product that is displaced by the nitrogen during the circulation of the dairy product from the flow stabilization means, can pass through said valve without any leakage of Dairy product through it.

According to a feature of the present packaging system, the flow stabilization means may have a flow pool.

As for the means for filling containers, they can comprise at least one supply outlet of the dairy product to the containers and additionally a nitrogen supply outlet for the same containers, which are gradually filled. The combustion means housed in the sealed space of the packaging unit, can present a Bunsen burner that can be combusted with the remaining oxygen of the entire process followed by the dairy product in accordance with the present invention. On the other hand, the packaging unit can additionally house UV radiation emitting means, which guarantee the sterilization of the packaging point to optimize the sterilization of the final packaged product to be distributed, and also the closest environment surrounding the container.

In addition, a second object of the present invention is a process for packaging dairy products using a packaging system described above, comprising the steps of pasteurization of the dairy product and subsequent homogenization, and further comprising the steps of:

- replacement of the oxygen in the dairy product with nitrogen in the first oxygen-nitrogen gas exchange means, in which the nitrogen that displaces the oxygen present in the dairy product is injected;

- passage of the dairy product through the flow stabilization means; which helps the presence of nitrogen in the dairy product to be distributed progressively while replacing oxygen; Y

- packaging of the dairy product, while combustion occurs with the oxygen present in the sealed space of the packaging unit.

Thanks to these characteristics, a dairy product packaging process is achieved in which the presence of oxygen in the dairy product is effectively replaced by nitrogen after pasteurization and homogenization, which avoids the introduction of oxygen after gas exchange. The effective replacement of oxygen is achieved to prevent oxidation and rancidity of the dairy product.

It is possible to improve the logistics for the arrival and durability of the product to the final customer, thus ensuring an increase in its consumption for the healthy improvement of the population. The elaboration maintains the characteristics, both legislative, normatively speaking, and potentially healthy of dairy products such as fresh pasteurized milk and packed for 60 days; as a consequence it is possible to ensure a preferred consumption date of a period such as that mentioned. Optionally between the passage of the milk product through the flow stabilization means and the packaging, the milk product passes through the second gas exchange means. This is achieved when an even more thorough removal of residual oxygen present in the dairy product is necessary.

Additionally, during packaging, UV radiation can be applied to the tight space and particularly to the packages containing the dairy product.

Advantageously, the pasteurization is carried out at between 75 ^e C and 83 ^e C and the packaging is carried out at a temperature below 8 ^e C. Thanks to this pasteurization temperature, it is possible to maintain an optimal taste of the dairy product at the same time as the presence of microorganisms in it is significantly reduced.

The process of the present invention has proven useful whether the dairy product is bovine or goat milk, which is not known in the state of the art.

Other features and advantages of the dairy product packaging system and the process followed by the same objects of the present invention will be apparent from the description of a preferred but not exclusive embodiment, which is illustrated by way of non-limiting example in the accompanying drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 .- It is a schematic view of a packaging system for dairy products according to the present invention;

Figure 2.- It is a schematic view of the first oxygen-nitrogen gas exchange means of the packaging system of Figure 1;

Figure 3.- It is a schematic view of a second oxygen-nitrogen gas exchange means of the packaging system of Figure 1; Y

Figure 4.- It is a schematic view of a packaging unit of the packaging system of Figure 1.

DESCRIPTION OF A PREFERRED EMBODIMENT As shown in the attached figures, a preferred but not exclusive embodiment of a system according to the present invention is shown. It should be mentioned that in the attached figures arrows have been used to indicate the direction of flow of the dairy product and dashed lines to schematically represent some elements.

In Figure 1 it can be seen that the packaging system 1 of dairy products advantageously comprises a receiving point 2 of a dairy product, which in the present preferred embodiment may be fresh milk of bovine or caprine origin. This dairy product is conducted to a pasteurization unit 3 linked to at least one homogenizer 4; The pasteurization unit 3 and the homogenizer 4 will not go into more detail since they will be any available in the market.

The packaging system 1 additionally comprises first oxygen-nitrogen gas exchange means 5 linked to the outlet of the homogenizer 4. The first oxygen-nitrogen gas exchange means 5 advantageously comprise at least one pressurized nitrogen injector 51 in the product Dairy, as shown in Figure 2. Pressurized nitrogen gas by dynamics and difference in gas density, will displace the oxygen present in the dairy product. This oxygen will leave the first oxygen-nitrogen gas exchange means 5 through an outlet valve 53 for the oxygen and thanks to the presence of at least one agitator 52 of the dairy product.

Continuing with Figure 1, it can be seen that flow stabilization means 6 are present between the first oxygen-nitrogen gas exchange means 5 and preferably second oxygen-nitrogen gas exchange means 7. In the present preferred embodiment the means Flow stabilization 6 has a flow pool that stabilizes the flow of milk product after receiving the nitrogen supply and in which nitrogen continues to replace oxygen; This flow pool may be any available to the person skilled in the art, although it will be guaranteed that the dairy product is kept in a tight condition against ambient air.

With respect to the second oxygen-nitrogen gas exchange means 7, it is shown in Figure 3 that preferably comprise an upright coil 71, such that in a condition of use a flow of milk product is capable of ascending, the coil 71 being present minus an exhaust valve 72 advantageously located in the part upper or higher of the coil in a condition of use. When the dairy product rises following the arrows shown in Figure 3, the oxygen that remains in the dairy product after passing through the flow pool also rises by the coil 71 and by gas transfer leaves the dairy product and is positioned in the upper part of the coil 71 where the exhaust valve 72 is located.

As can be seen in Figure 4, the packaging system 1 has at least one packaging unit 8 associated with the output of the second oxygen-nitrogen gas exchange means 7, the packaging unit 8 comprising a sealed space that houses means for filling containers 81, 84 and combustion means 83. The means for filling containers 81, 84 comprise at least one supply outlet of the dairy product 81 and advantageously a nitrogen supply outlet 84 to the containers 9; This configuration allows the supply of dairy and nitrogen products within the containers 9 to be carried out in a coordinated manner, being able to choose the optimum moment in which said supplies are carried out; In addition the configuration allows to optimize the space. The nitrogen supply outlet 84 allows to fill the hollow space present in the containers 9 filled with milk product to prevent the entry of other gases. The supply outlet of the dairy product 81 and the nitrogen supply outlet 84 are in fluid communication with a drive equipment for the dairy product as well as nitrogen; These drive teams are coordinated with each other. It will be possible that during the filling of the containers 9, they can be agitated with a stirring device (not shown) or that the means for filling containers 81, 84 can remove the dairy product, to help the correct diffusion of nitrogen in said container. product.

Subsequent to the supply of dairy and nitrogen products, the containers 9 are properly sealed for sale. As for the combustion means 83, they preferably have a Bunsen burner that allows combustion of the possible remaining oxygen in the flow of milk product to be packaged. It will be obvious to the person skilled in the art that the lighter of the Bunsen type or plurality of the lighter of the Bunsen type may be replaced by any other prior art system in which the possible remaining oxygen has just been combusted. The containers used may preferably be made of polyethylene terephthalate or PET, although it will be obvious to the person skilled in the art to use any other material available in the state of the art with similar properties. Advantageously, the packaging unit 8 additionally houses UV emitting means 82, which can be emitted in any wavelength such that it allows the sterilization of germs in the sealed space of the packaging unit 8 and particularly in the containers 9 to be filled. The above-mentioned packaging system 1 will be executed following a dairy product packaging process comprising the steps of pasteurization of the dairy product received from the milking point in the pasteurization unit 3. The reception, for example, of raw milk can be carried out in a stainless steel tank or similar preferably with a maximum of two days of milking. Before downloading, we proceed to analyze: fat, protein, inhibitors, somatic cells and also its water content if it exists. This ensures the quality of the dairy product as well as compliance with the scales established by current regulations. Pasteurization will preferably be carried out at a temperature between 75 ^and C and 83 ^and C for about three minutes, which allows the organoleptic properties to be maintained at an optimum level as well as the nutrients, for example, of fresh milk.

Subsequent to pasteurization a subsequent homogenization of the dairy product will be carried out in the homogenizer 4, for example of the shear type; This process is done to avoid the separation of the components of the milk and to keep them together. No further details will be entered into with these stages as they will be carried out following prior art techniques. The following steps are continued:

- replacement of oxygen present in the dairy product with nitrogen in the first oxygen-nitrogen gas exchange media 5. At this stage, nitrogen is injected as an inert gas and the latent oxygen is eliminated from the dairy product. At the same time, and preferably the stirrer 52 will be removing the milk product in the stage and turning between the surface and the interior thereof to remove particles of dissolved air in the dairy product;

- passage of the milk product through the flow stabilization means 6, where it is cooled to 8 ^e C; Y

- packaging. The packaging can be carried out at a temperature below 8 ^e C and during it UV radiation is applied to the containers 9 and combustion takes place with the oxygen present in the sealed space of the packaging unit 8.

In the present preferred embodiment, between the passage of the dairy product through the flow stabilization means 6 and the packaging, the passage of the dairy product occurs through the second gas exchange means 7. Thanks to this stage the output can be achieved of the possible residual oxygen of the dairy product, which in the state of the art remains in the dairy product. As already mentioned, the present packaging procedure is designed to be applied whether the dairy product is bovine or goat milk.

From the aforementioned procedure, a laboratory test with milk product samples has been carried out. Specifically, some samples of fresh cow and goat milk were used. This trial has shown the behavior of milk over the weeks in a packaging such as marketing.

The following regulations were applied to carry out the test: For food in general: R.D. 3484 / 2,000; BOE 12 / 2.001. Reg. 2,073 / 2,005 mod.

1,444 / 2,007 mod. RD135 / 2010 of February 12; BOE February 25, 2010; and for pasteurized milk: Regulation EC 2073/2005 of the European Commission section 2.2.1. Only referred to enterobacteria (N = 5, c = 2, m: <1, M = 5 cfu / ml). First respectively 1 liter of cow milk and 1 liter of goat milk were provided fresh pasteurized at 75 ^e C. Fractions Aliquots of both types of milk were subjected to the treatment described below performed inside an LAF laminate, with irradiation of ultraviolet light, and in the presence of the flame of a bunsen burner to ensure a sterile atmosphere during operation. 80 mL of pasteurized milk was poured into a 100 mL glass jar. The cannula connected to the pressure reducer of the nitrogen bottle was immersed in the bottle and the gas in the milk contained in the bottle was bubbled at a flow of 2.0 ± 0.2 L / min of nitrogen for 2 minutes, moving gently the cannula in a circular motion along the entire inner base of the bottle ensuring complete mixing and homogenization of the milk for the replacement of dissolved air in the milk with nitrogen. After the set time, the cannula was placed above the level of the milk in the bottle, the nitrogen flow was increased to a value of 8.0 ± 1.0 L / min, and the air was expelled from the neck of the bottle and the cap for 30 seconds, after which the bottle was capped while continuing to dispense nitrogen until closing. This operation was repeated for a total of five bottles of cow's milk and five bottles of goat's milk.

The ten bottles obtained were labeled to identify the type of milk and stored in a laboratory refrigerator at a temperature of 4.8 ± 0.2 ^e C.

The remainder of the pasteurized milk was left covered in their respective original containers and stored in a refrigerator at the same temperature.

The microbiological analysis was performed 8 weeks after the process of removing air from the milk by displacement with nitrogen. It investigated the following variables:

-Organoleptics: Appearance and smell.

-Microbiological. The determination of the microorganisms provided for in the legislation was carried out plus quality counselors. Specifically they include: Mesophiles,

In tero bacteria, E. Coli, Staphylococci Coagulase +, Salmonella and Listeria monocytogenes.

Pasteurized milk preserved under a nitrogen atmosphere according to the object of the present invention, at 5 ^e C for 8 weeks retained its characteristic odor unlike milk stored at the same temperature in the presence of air. The microbiological analysis revealed that the bottles treated strictly with this procedure comply with the most restrictive regulations, which is specific for pasteurized milk, Regulation EC 2073/2005 of the European Commission section 2.2.1. Regarding the results obtained in a general organoleptic assessment, carried out during the test, it was found that the packed samples of cow's and goat's milk following the characteristics of the present invention had a normal odor and color for cow's milk at eight weeks or goat

As for the milk samples not packaged following the present invention, it was found that at 28 days they had a strong sour smell in the case of cow's milk or very strong and unpleasant in the case of goat's milk. These results indicate that the application of this packaging procedure that includes the effective removal of air from cow's or goat's milk by nitrogen and its storage in this atmosphere protects it from the development of undesirable microorganisms while maintaining in principle the nutritional properties of pasteurized milk .

The details, shapes, dimensions and other accessory elements, as well as the materials used in the manufacture of the dairy product packaging system and the procedure followed by it of the invention may be conveniently replaced by others that do not depart from the scope defined by the claims included below.

Claims

one . Packaging system for dairy products (1) comprising a pasteurization unit (3) linked to at least one homogenizer (4), characterized in that it additionally comprises first linked oxygen-nitrogen gas exchange means (5) at the outlet of the homogenizer (4), presenting flow stabilization means (6) between the first oxygen-nitrogen gas exchange means (5) and at least one packaging unit (8) associated with the outlet of the means of flow stabilization (6), the packaging unit (8) comprising a sealed space that houses means for filling containers (81, 84) and combustion means (83), in which between the stabilization means of flow (6) and the packaging unit (8), second oxygen-nitrogen gas exchange means (7) are present.

2. Dairy packaging system (1) according to claim 1, wherein the second oxygen-nitrogen gas exchange means (7) comprises an upright coil (71), such that in a condition of use a product flow Dairy is likely to rise, with the coil (71) presenting at least one exhaust valve (72).

3. Dairy packaging system (1) any one of the preceding claims, wherein the first oxygen-nitrogen gas exchange means (5) comprises at least one pressurized nitrogen injector (51) in the dairy product, a outlet valve (53) for oxygen and at least one agitator (52) of the dairy product.

4. Dairy packaging system (1) according to any of the preceding claims, wherein the flow stabilization means (6) have a flow pool.

5. Dairy product packaging system (1) according to any of the preceding claims, wherein the means for filling containers comprises at least one supply outlet of the dairy product (81) to packages (9).

6. A dairy product packaging system (1) according to claim 5 wherein the means for filling containers additionally comprises a nitrogen supply outlet (84).

7. Dairy packaging system (1) according to any of the preceding claims, wherein the combustion means (83) have a Bunsen burner.

8. Packaging system for dairy products (1) according to any of the preceding claims, wherein the packaging unit (8) additionally houses UV emitting means (82).

9. Method of packaging dairy products using a packaging system according to any of the preceding claims, comprising the steps of pasteurization of the dairy product and subsequent homogenization, characterized in that it further comprises the steps of:

- replacement of oxygen in the dairy product with nitrogen in the first oxygen-nitrogen gas exchange means (5);

- passage of the dairy product through the flow stabilization means (6); Y

- packaging of the dairy product while combustion occurs with the oxygen present in the sealed space of the packaging unit (8);

in which between the passage of the milk product through the flow stabilization means (6) and the packaging, the milk product passes through the second oxygen-nitrogen gas exchange means (7).

10. Method of packaging dairy products according to claim 9 wherein the pasteurization is carried out between 75 ^e C and 83 ^e C.

eleven . Method of packaging dairy products according to any of claims 9-10 wherein the packaging is carried out at a temperature below 8 ^e C.

12. Method of packaging dairy products according to any of claims 9-1 1, during which UV radiation is applied to the sealed space and particularly to the containers during packaging.

13. Method of packaging dairy products according to any of claims 9-12 wherein the dairy product is bovine or goat milk.