FR3078691A1 - POCKET OF STORAGE OF NUTRITIONAL LIQUID EXTRACTS, PACKAGING AND PACKAGING METHOD - Google Patents

Abstract

The invention proposes a pocket (100) for storing liquid nutritional extracts, which is waterproof and sterilizable, comprising: a compartment (101) for storing nutritional liquid extracts; An inlet manifold (110) provided with a tamper-evident clamp (111); and an outlet pipe (120) provided with: a first unidirectional valve (121), called "upstream", and a second unidirectional valve (122), called "downstream"; and - a withdrawal device (123) arranged between the two unidirectional valves.

Description

POCKET FOR STORING NUTRITIONAL LIQUID EXTRACTS, PACKAGING AND PACKAGING METHOD.

The present invention relates to a method for packaging nutritional liquid extracts, as well as a packaging for nutritional liquid extracts guaranteeing the conservation and quality of the bioactive molecules.

Nutritional liquid extracts are understood (denoted ELN "below) extracts of plants, cyanobacteria, fungi, yeasts, microalgae, macroalgae, mother liquors and its variants containing active molecules from the living world such as vitamins, trace elements, proteins , sugars, etc.

These ELNs are used in dietetics, nutraceuticals, seasonal cures, food supplements, parapharmaceuticals, pharmaceuticals, veterinarians, and in sports drinks.

ELN have the common characteristic of being very fragile, and sensitive to the conditions in which they are handled and stored.

Conventionally, these ELNs are sterile packaged in single doses such as: glass ampoules, plastic single doses, small bottles in individual glass ampoules.

To guarantee axenia, the industrial processes implemented are very expensive, because they require complex high-tech infrastructures, competent personnel and very large investments. Their profitability therefore requires industrial production in very large quantities, preventing local economic players from marketing ELNs.

A first objective of the invention is therefore to propose a packaging process and packaging allowing versatile and economical packaging, allowing production on a small scale, on a medium scale or on an industrial scale.

Another object of the invention is to provide a packaging method and packaging allowing multidose packaging, preferably a large number of doses, as opposed to the individual doses conventionally sold.

Indeed, individual doses generate a very large amount of waste rarely recycled, which is unfortunate for products that are part of an ecological movement of human well-being and nature.

The objective of the present invention is therefore to propose a method and a packaging making it possible to reduce the quantity of waste at an equal number of doses.

In addition, known industrial processes require heating of the product to limit the development of microbiological contamination: bacteria, yeasts, fungi or others.

However, this heating is incompatible with most ELNs, so that the products sold often have poor nutritional qualities.

It has already been proposed to replace the heating of products by the addition of preservatives, alcohol, or glycerin, but these additives distort the products and go against the will of consumers to buy natural products and healthy.

The present invention therefore aims to propose a conditioning process and packaging guaranteeing preservation and intrinsic natural qualities of the bioactive molecules throughout its use (withdrawal of doses), while avoiding the heating of the products and the addition of preservatives.

Flexible sterilizable plastic bags are known from the state of the art for storing blood, for example. The outlet has an orifice to which a catheter is connected to allow intravenous administration of blood.

This structure is not suitable for the packaging and distribution of ELNs, because it does not allow withdrawal per dose, but a simple continuous flow by gravity.

There are also flexible storage bags used in the field of biotechnology to store and transport vaccines, culture media or protein solutions.

In addition to their prohibitive price (several tens of euros for a 1 liter bag), their use is reserved for laboratories and racking can only be done under drastic sterility conditions, very far from the racking conditions of the present invention.

Finally, the packaging of liquid, such as wine, is known in flexible bags enclosed in a cardboard container, conventionally called cubitainer or "Bag-in-box" in English.

This type of packaging is also not suitable for ELNs, because they do not allow the axenicity necessary for the conservation of ELNs to be respected throughout the racking. In addition, they do not allow withdrawal by a limited, precise and constant dose. Indeed, when the bag is full, a determined pressure on the tap delivers a large amount of wine, while when the bag is almost empty, the same pressure on the tap allows only a small amount of wine to be obtained.

The present invention therefore aims to provide packaging and a packaging method which does not have the above drawbacks.

To this end, the invention provides a flexible storage pocket provided with an inlet tubing designed to allow simple, safe and hygienic filling, as well as an outlet tubing designed to allow delivery of restricted, precise and constant, also guaranteeing axenia throughout the rackings.

The invention also proposes to use a two-part packaging, a first part consisting of the previous flexible bag and a second part consisting of a rigid container capable of holding the flexible bag at a determined angle, preferably vertically.

Thus, the present invention provides a bag for storing nutritional liquid extracts, waterproof and sterilizable, comprising:

• a compartment for storing nutritional liquid extracts;

• an inlet tube fitted with a tamper-proof clamp; and • an outlet pipe fitted with:

- a first unidirectional valve, called "upstream", and a second unidirectional valve, called "downstream";

- a withdrawal device arranged between the two unidirectional valves.

According to other embodiments, which can be combined with one another:

• the storage bag can include a first opening connected to the inlet tubing and a second opening connected to the outlet tubing;

The storage bag can comprise a single opening connected by a tubular T-shaped portion on the one hand to the inlet tubing and on the other hand to an outlet tubing, the tubular T-shaped portion further comprising a means closing to temporarily close the outlet tubing;

• the inlet tubing can be connected to an absolute grade filter between 0.1 pm and 0.2 pm;

• the withdrawal device can be removably mounted between the two one-way valves;

• the withdrawal device may include a sampling chamber equipped with a piston;

• the sampling chamber may include a means of abutment of the piston;

• the racking device can include:

- a sampling chamber provided with an end intended to be arranged between the two unidirectional valves of the outlet tube, and a shoulder surrounded by a collar;

- a piston connected to a push button; and

- A helical spring arranged in abutment against the shoulder and against the push button, the latter being guided in translation by the flange of the sampling chamber;

• the stop means can be adjustable in position to allow an adjustable stroke of the piston;

• the upstream valve can be a non-return valve and the downstream valve is an anti-siphon valve;

• the upstream and downstream valves can be anti-siphon valves; and / or • the storage compartment may have two non-parallel edges, converging with respect to each other, the outlet tube being arranged at one end of these edges, so that when the pocket is in the position of use, the liquid is guided in the direction of the outlet tubing.

A subject of the invention is also a packaging for withdrawing nutritional liquid extracts for a previous bag, the packaging comprising, with reference to the position of use, an upper compartment intended to receive the bag, and a lower compartment communicating with the upper compartment by an opening through which the outlet pipe ό

is intended to pass, the lower compartment further comprising an opening towards the outside of the packaging and intended to allow at least one free end of the outlet pipe to pass.

According to other embodiments, which can be combined with one another:

• the lower compartment may include a second opening to the outside intended to allow the withdrawal device to pass;

• the upper compartment may include a means of hanging the pocket;

• the upper compartment and the lower compartment can be separated by a partition inclined relative to the horizontal, with reference to the position of use, the pocket being intended to rest on the inclined partition so that the outlet pipe is lower than the pocket; and / or • the packaging may include a third compartment provided with a reclosable opening for the storage of a removable withdrawal device intended to be fluidly connected to the outlet pipe between the two valves.

The invention also relates to a method for filling a previous bag, the method comprising the following steps:

(a) connecting the inlet tubing of several previous bags to a filling pipe having one end provided with an absolute grade filter between 0.1 pm and 0.2 pm intended to be connected to an extract tank nutritional liquid, and one end provided with a vent equipped with a non-return valve, in order to constitute a chain of pockets;

(b) sterilizing the chain of pockets thus formed;

(c) connect the string of sterilized bags to a reservoir of nutritional liquid extract and circulate the liquid nutritional extract in the filling line from the reservoir to the bags until each bag is filled;

(e) activating each tamper-evident clamp to hermetically and definitively seal the inlet tubing of each pocket;

(f) separate each pocket thus sealed from the filling pipe.

According to other embodiments, which can be combined with one another:

• the method may further comprise, before step (e), a step (d) of filling the bag with a gas under pressure; and / or • the gas can be chosen from nitrogen and carbon dioxide.

Other characteristics of the invention will be set out in the detailed description below, made with reference to the accompanying drawings, which respectively represent:

Figure 1, a schematic plan view of a first embodiment of a pocket for storing nutritional liquid extracts according to the invention comprising an inlet manifold and an outlet manifold independent;

Figure 2, a schematic plan view of a second embodiment of a pocket for storing nutritional liquid extracts according to the invention comprising a single opening connected on the one hand to an inlet pipe and on the other leaves to an outlet pipe;

FIG. 3, a schematic plan view of an exemplary assembly for filling a plurality of bags for storing nutritional liquid extracts according to the invention;

Figures 4 to 8, schematic plan views of five different embodiments of a racking package for nutritional liquid extracts according to the invention;

Figure 9, a schematic sectional view of an automatic withdrawal device provided with a push button, and intended to equip a pocket for storing nutritional liquid extracts according to the invention; and Figure 10, a schematic sectional view of a variant of the drawing device of Figure 9, provided with a means for adjusting the dose.

FIG. 1 illustrates a first embodiment of a bag 100 for storing nutritional liquid extracts according to the invention.

The bag is preferably made up of two sheets of food-grade polymer, waterproof and sterilizable, sealed against each other to delimit a compartment for storing nutritional liquid extracts. In FIGS. 1 and 2, this structure is illustrated by a dotted line which materializes the weld lines 101 between the two sheets and delimits the storage compartment 102.

Advantageously, the polymer is chosen from EVA (ethylene vinyl acetate), EVOH (ethylene vinyl alcohol), PVC (polyvinyl chloride) or PE (polyethylene).

According to the invention, the pocket 100 comprises:

• an inlet tube 1 10 provided with a tamper-proof clamp 1 1 1 which is activated only when the bag is filled; and • an outlet pipe 120 provided, by reference to the direction of circulation of the fluid at the outlet:

- A first unidirectional valve 121 called "upstream" and a second unidirectional valve 1 22 called "downstream"; and

- a withdrawal device 123 arranged between the two unidirectional valves 121 and 122. In the example illustrated, the withdrawal device 123 comprises a sampling chamber 125 equipped with a piston 1 26.

In the preferred embodiment illustrated in FIG. 1, the bag 100 comprises a first opening 103 connected to the inlet pipe 1 1 0 and a second opening 104 connected to the outlet pipe 1 20.

When filling the bag (described in more detail with reference to Figure 3), the solution of nutritional liquid extracts flows through the inlet tube 1 1 0 in the direction of the arrow Fl. This solution passes through d '' a filter 1 1 2 of absolute grade between 0.1 pm or 0.2 pm.

This filter can be integrated into the inlet tubing, but it is preferably simply connected upstream of this inlet tubing 1 1 0 during sterilization and kept during filling and then recovered after filling the or each bag.

When a user wants to take a dose of solution, he pulls the piston in the direction of arrow F2, which pumps the liquid from the storage compartment 101 through the first one-way valve 121 upstream, in the direction of the arrow F3. The second unidirectional valve swallows 1 22 is blocked and remains closed since the suction caused by the recoil of the piston tends to circulate the liquid or the air located downstream of the second unidirectional valve 122 towards the piston, therefore against the direction of flow of said second one-way valve 122.

Then the user pushes the piston 126 in the direction of arrow F4. In this case, the liquid flows through the second one-way downstream valve 1 22, while the first upstream one-way valve is blocked to prevent the return of the liquid to the pocket.

Thus, a small volume of liquid is ejected from the bag without risk of contamination of the liquid contained in the storage compartment.

The volume of liquid ejected depends on the volume of the sampling chamber 125 and on the distance over which the piston has been moved back into the chamber.

Advantageously, the chamber is transparent and graduated, so that the user can know and choose the volume of liquid that he pumps.

In an alternative embodiment, the sampling chamber comprises a means of abutment of the piston, so that the user only has to pull the piston up to the stop to pump a dose of predetermined constant volume.

Advantageously, the stop means is adjustable in position to allow an adjustable stroke of the piston and therefore to allow an adjustable sampling volume. Once the sampling volume has been chosen and adjusted, the user will only have to pull the plunger up to the stop to withdraw a dose of constant volume.

The sampling chamber can take the form of a syringe. Preferably, the latter is removably mounted between the two unidirectional valves 121 and 122.

To this end, the outlet tubing comprises a reversible fixing end piece of the sampling chamber arranged between the two valves 121 and 1 22. For example, it may be a luer sampling connector making it possible to connect a dosing syringe . This luer tip allows you to safely adjust and place the tip of the syringe and thus choose the volume of liquid withdrawn from the bag and constituting the dose of product used.

Unidirectional valves are non-return valves or anti-siphon valves. For example, the upstream valve 121 can be a non-return valve and the downstream valve 122 can be an anti-siphon valve.

1

The best results are obtained when the two upstream 121 and downstream 122 valves are anti-siphon valves: there is a total absence of gravity leakage and no risk of air entering between the two valves 121 and 122 nor in the storage compartment 101, thus ensuring perfect axenicity throughout the use of the pocket.

A second embodiment is illustrated in FIG. 2, in which the bag 200 only comprises a single opening 203 connected by a tubular T-shaped portion 205 on the one hand to the inlet manifold 210 and on the other hand to a outlet pipe 220.

The T-shaped tubular portion 205 further comprises a closing means 206 for temporarily closing the outlet tubing when the bag is filled by the inlet tubing 210.

The outlet tubing 220 is similar to the outlet tubing 1 in Figure 1.

The fittings, the pipes 110-210-120-220, the one-way valves 121-122 and the filter 112 are chosen to withstand the conditions and constraints associated with sterilization.

For example, the filter 1 1 2 is a Lifeassure PDA 020 brand filter from the company 3M which can be sterilized by ionization. Alternatively, filters of the “Sartobran” brands from Sartorius can be sterilized by autoclave.

The bags are sterilized when the assembly of FIG. 3 is carried out.

This figure illustrates an example of a packaging method according to the invention of the bags of FIG. 1.

Firstly, the inlet tubing 1 1 0 and the outlet tubing 120 of several empty bags 100 are connected to a filling pipe 300 having an end 301 provided with an absolute grade filter

302 between 0.1 pm and 0.2 pm intended to be connected to a reservoir of nutritional liquid extract (not illustrated).

The bags can thus be filled with a perfectly axenic filtered liquid. This axenic filtration is obtained by filtering with an absolute grade filter of 0.2 pm or 0.1 pm. Suitably, this filter is placed upstream of the connections of the line 300 joining the pockets.

Thus with a single 0.2pm filtration cartridge, it is possible to fill a few tens or hundreds of interconnected bags and to divide the cost of filtration over all of the bags.

For example, with a 5 inch lifeassure PDA 020 cartridge you can fill between 500 and 1,000 1 liter bags. Thus, the size of the absolute filter is adjusted from 0.2 and 0.1 μm to the number of interconnected bags, according to the productions, samples, pilot or industrial envisaged and according to the nature of the product to be packaged. Indeed the liquid extracts do not all filter so easily. Clogging with protein solutions can reduce the number of bags compared to an aqueous solution of vitamins and trace elements.

The other end 303 of the pipe 300 is provided with a vent equipped with a non-return valve, to allow the air present in the string of pockets thus constituted to be evacuated. Thus before any filling, it is advisable to purge the air contained in the supply line 300 from the bags to then fill them under vacuum and to avoid oxidation of sensitive molecules.

Once the assembly has been carried out, the rosary is sterilized, for example by ionization or autoclave.

The string of sterilized bags is then connected to a reservoir of nutritional liquid extract, preferably by means of a single filter 112 of absolute grade between 0.1 μm or 0.2 μm, and one circulates the nutritional liquid extract in the filling line 300 from the reservoir to the bags until each bag is filled.

Thanks to the unidirectional valves, the pockets are filled in the direction of the arrows F6 then, when they are full, let the liquid flow to the following pockets in the direction of the arrows F7.

Once the bags are filled, each tamper-evident clamp 1 1 1 is activated to hermetically and definitively seal the inlet tubing of each pocket, then each pocket thus sealed is separated from the filling pipe.

Another less practical solution is to heat weld the inlet pipe after filling. The weld thus produced with a suitable machine must be perfectly carried out to be waterproof and hold within the life of the product. After this operation the pocket can be detached from the assembly.

In the case of bags according to the embodiment of FIG. 2, the filtered liquid is conveyed bag by bag, by means of temporary closures of the supply pipes and outlet pipes 220, so that it does not There is only one pocket at a time that is filled with the correct volume.

Temporary closures are carried out using mohr forceps, clamps, or any system allowing the pipes to be crushed and preventing the passage of liquid. Another solution is to install a valve before the bag. By these sets of valves or temporary closure, it is possible to fill one by one the pockets thus arranged.

The use of a metering pump, for example a peristaltic pump, ensures the filling of the bag with a chosen volume. The pocket to be filled can also be placed on a scale, and by measuring the mass, as a function of the density, the volume present in the pocket is then known.

In an advantageous embodiment, the packaging method comprises, before the step of activating the tamper-evident clamps, a step of filling the bag with a pressurized gas, preferably nitrogen or carbon dioxide. This pressurized gas promotes emptying of the bag and ensures that all the liquid is used when the bags are in the use position, that is to say outlet pipe down in the direction of gravity.

To ensure proper use of the bag and good preservation of the product, the invention provides for combining it with rigid packaging, such as a cardboard box.

A first example of racking packaging according to the invention is illustrated in FIG. 4. In this figure as in FIGS. 5 to 8, only the outlet pipe has been illustrated for the sake of clarity. The inlet tubing is, in practice, reduced to the shortest possible.

The packaging 400 comprises, with reference to the position of use, an upper compartment 41 0 intended to receive the bag 1 00, and a lower compartment 420 communicating with the upper compartment 41 0 by an opening 430 through which the tubing of exit is intended to pass.

The lower compartment 420 further comprising an opening 440 towards the outside of the package 400 and intended to allow at least one free end 127 of the outlet pipe to pass.

In FIG. 4, the free end 127 as well as the sampling chamber are arranged outside the packaging 400.

The packaging 400 of FIG. 4 also includes a third compartment 460 provided with a reclosable opening (not shown) for the storage of the sampling chamber 125 (and of the piston 126) when these are not used.

In this case, of course, the sampling chamber is removably mounted to be fluidly connected to the outlet tubing between the two valves.

FIG. 5 illustrates an alternative in which only the end 127 passes through the orifice 440, the sampling chamber 125, and more particularly the piston 126 being accessible via a second opening 450 towards the outside.

FIG. 6 illustrates another variant of packaging according to the invention, in which the upper compartment 410 and the lower compartment 420 are separated by a partition inclined 470 relative to the horizontal, with reference to the position of use. In this package, the pocket 100 is intended to rest on the inclined partition 470 so that the outlet pipe 1 20 is lower than the pocket.

This arrangement makes it possible to ensure that all of the liquid can leave the pocket 1 00.

The latter can be fixed to the packaging or the partition can include a stop to prevent the pocket from slipping.

Figures 7 and 8 illustrate embodiments of a package 500 according to the invention in which the bag 100 is suspended so that the outlet pipe 1 20 is located downwards.

In this case, the upper compartment 510 comprises a hanging means 511 of the pocket 100, the latter also comprising a hanging means 1 15. In FIGS. 7 and 8, these hanging means are a hook 511 (seen in section) and a lug 1 1 5 provided with a hole for the hook 511.

Advantageously, the pocket 100 consists of two sheets welded against each other along weld lines 101 delimiting the storage compartment 102 such that the storage compartment has

Ιό two lower edges (with reference to the position of use in which the bag is suspended) 101a and 101b not parallel and convergent with respect to each other.

The outlet tube 120 is arranged at one end of these lower edges 1 01 a and 1 01 b, so that when the bag is suspended, all the liquid is guided in the direction of the outlet tube 1 20.

This arrangement limits the dead volumes and therefore the losses of unused liquid.

As in the previous embodiments, the upper compartment 510 communicates with a lower compartment 520 through an orifice 530.

The lower compartment 520 also includes an orifice 540 towards the outside of the packaging to allow at least the free end 12 27 of the outlet tube 120 to pass.

In a similar manner to FIG. 5, FIG. 8 illustrates a package comprising a second orifice 550 towards the outside to allow the sampling chamber 125 and the piston 126 to pass.

Figures 9 and 10 illustrate two embodiments of withdrawal devices provided with a push button particularly suitable for the embodiments of Figures 5 and 8 and advantageously replace the sampling chamber provided with a manual syringe-type piston.

Thus the packaging offers a qualitative presentation in which only a push button and the liquid outlet 127 are visible.

As illustrated in FIG. 9, the withdrawal device 600 comprises a sampling chamber 601 provided with an end 602 intended to be arranged between the two unidirectional valves of the outlet pipe of the bag according to the invention.

The sampling chamber 601 also includes a shoulder 603 surrounded by a collar 604.

The withdrawal device 600 further comprises a piston 61 0 connected to a push button 61 1 by a rod 61 2.

The withdrawal device 600 also comprises a helical spring 620 arranged in abutment against the shoulder 603 and against the push button 61 1, the latter being guided in translation by the flange 604.

Advantageously, the push-button 61 1 comprises a rib 614 intended to be in abutment against an end-of-travel stop 605 of the flange 604 at rest. To this end, in this position the spring 620 is in slight compression.

Thus, in use, when the user presses the button, it drives out the liquid contained in the sampling chamber, which can flow towards the outlet 127 thanks to the anti-siphon valves 121 and 122 of the outlet pipe 1 20 .

By releasing the push button 611, the spring 620 relaxes and pulls on the piston 61 0 which automatically pumps the liquid into the sampling chamber 601 for a next drawing off.

The automatic withdrawal device illustrated in FIG. 10 differs from that illustrated in FIG. 9 by the presence of a means 705 for adjusting the dose.

This adjustment means 705 comprises a screw pitch 705a secured to the flange 604 and an end of travel stop 705b provided with a thread engaged with the screw pitch 705a.

The push button 61 1 also includes a rib 614 intended to come into contact with the end of travel stop 705b when the spring 620 relaxes.

Depending on the screwing of the end stop 705b, the stroke of the push button and therefore of the piston 610 is more or less long. The volume of liquid withdrawn is therefore more or less significant.

The invention therefore allows versatile and economical packaging, since the pouch and packaging according to the invention are inexpensive and make it possible to condition a large number of different liquids, since they can be very easily sterilized before filling, independently of the liquid. to contain.

The conditioning process and packaging according to the invention therefore guarantee preservation and intrinsic natural qualities of the bioactive molecules throughout its use (withdrawal of doses), while avoiding the heating of the products and the addition of preservatives.

In addition, they allow production on a small, medium or industrial scale.

Finally, they allow a very economical multidose packaging which can be easily recycled or sent back to the manufacturer in order to reduce the amount of waste.

Claims (20)

1. Pouch (100) for storing nutritional liquid extracts, waterproof and sterilizable, characterized in that it comprises: • a compartment (101) for storing nutritional liquid extracts; • an inlet pipe (1 1 0) fitted with a tamper-evident clamp (111); and • an outlet pipe (120) provided with: - A first unidirectional valve (121), called "upstream", and a second unidirectional valve (1222), called "downstream"; - a withdrawal device (123) arranged between the two one-way valves. 2. Pocket for storing nutritional liquid extracts according to claim 1, comprising a first opening (103) connected to the inlet tubing (1 1 0) and a second opening (1 04) connected to the outlet tubing (1 20). 3. Pocket (200) for storing nutritional liquid extracts according to claim 1, comprising a single opening (203) connected by a tubular T-shaped portion (205) on the one hand to the inlet tubing (210) and d on the other hand to an outlet pipe (220), the T-shaped tubular portion further comprising a closure means (206) for temporarily closing the outlet pipe. 4. Pocket for storing nutritional liquid extracts according to any one of claims 1 to 3, in which the inlet tubing is connected to an absolute grade filter (1 1 2-301) between 0.1 pm and 0.2 pm. 5. Pocket for storing nutritional liquid extracts according to any one of claims 1 to 4, in which the withdrawal device is removably mounted between the two unidirectional valves. 6. Pocket for storing nutritional liquid extracts according to any one of claims 1 to 5, in which the withdrawal device comprises a sampling chamber (125-601) equipped with a piston (126610). 7. Pocket for storing nutritional liquid extracts according to claim 6, in which the sampling chamber (125-601) comprises a stop means (605-705-614) of the piston (126-610). 8. Pocket for storing nutritional liquid extracts according to any one of claims 1 to 7, in which the withdrawal device comprises: • a sampling chamber (601) provided with an end (602) intended to be arranged between the two unidirectional valves (121, 122) of the outlet pipe (120), and a shoulder (603) surrounded by a collar (604). • a piston (61 0) connected to a push button (61 1); and • a helical spring (620) arranged in abutment against the shoulder (603) and against the push button (61 1), the latter being guided in translation by the flange (604) of the sampling chamber (601). 9. Pocket for storing nutritional liquid extracts according to claim 7 or 8, in which the stop means (705-614) is adjustable in position to allow an adjustable stroke of the piston. 1 0. Pocket for storing nutritional liquid extracts according to any one of claims 1 to 9, in which the upstream valve is a non-return valve and the downstream valve is an anti-siphon valve. 1 1. Pocket for storing nutritional liquid extracts according to any one of claims 1 to 9, in which the upstream and downstream valves are anti-siphon valves. 1 2. Pocket for storing nutritional liquid extracts according to any one of claims 1 to 11, in which the storage compartment has two edges (10la-10lb) which are not parallel, convergent with respect to each other, the outlet tubing being arranged at one end of these edges, so that when the bag is in the use position, the liquid is guided in the direction of the outlet tubing. 13. Packaging (400-500) for drawing off nutritional liquid extracts for a bag according to any one of claims 1 to 12, characterized in that it comprises, by reference to the position of use, an upper compartment ( 410-510) intended to receive the pocket, and a lower compartment (420-520) communicating with the upper compartment through an opening (430-530) through which the outlet pipe is intended to pass, the lower compartment comprising, in in addition, an opening (440540) towards the outside of the packaging and intended to allow at least one free end of the outlet tubing to pass. 14. Packaging according to claim 13, wherein the lower compartment comprises a second opening (450-550) to the outside intended to allow the withdrawal device to pass. 15. Packaging any one of claims 1 3 or 14, wherein the upper compartment comprises means for suspending (511) the pocket. 16. Packaging any one of claims 1 3 or 14, wherein the upper compartment and the lower compartment are separated by a partition inclined (470) relative to the horizontal, with reference to the position of use, the pocket being intended to rest on the inclined partition so that the outlet pipe is lower than the pocket. 17. Packaging any one of claims 13 to 16, wherein the packaging comprises a third compartment (460) provided with a reclosable opening for the storage of a removable withdrawal device intended to be fluidly connected to the outlet pipe between the two valves. 1 8. A method of filling a bag according to any one of claims 1 to 1 2, characterized in that it comprises the following steps: (A) connecting the inlet tubing of several bags according to any one of claims 1 to 12 to a filling pipe having an end provided with an absolute grade filter between 0.1 pm and 0.2 pm intended to be connected to a reservoir of nutritional liquid extract, and one end provided with a vent equipped with a non-return valve, in order to constitute a chain of pockets; (b) sterilizing the chain of pockets thus formed; (c) connecting the string of sterilized bags to a reservoir of nutritional liquid extract and circulating the nutritional liquid extract in the filling line from the reservoir to the bags until each bag is filled; (e) activating each tamper-evident clamp to hermetically and definitively seal the inlet tubing of each pocket; (f) separate each pocket thus sealed from the filling pipe. 19. The method of claim 18, further comprising, before step (e), a step (d) of filling the bag with a gas under pressure. 20. The method of claim 19, wherein the gas is selected from nitrogen and carbon dioxide.