WO2016116695A1

WO2016116695A1 - Device for carrying out fermentation tests with a small volume of must

Info

Publication number: WO2016116695A1
Application number: PCT/FR2016/050101
Authority: WO
Inventors: Christian POUPOT
Original assignee: Universite de Bordeaux; Institut Polytechnique De Bordeaux
Priority date: 2015-01-20
Filing date: 2016-01-20
Publication date: 2016-07-28
Also published as: FR3031752A1

Abstract

The invention relates to a device for carrying out fermentation tests, said device comprising a first chamber (12) configured to receive the must, characterised in that the device comprises a second chamber (14) positioned above the first chamber (14) and an automatic return system which comprises a first pipe (44) configured to return a liquid from the first chamber (12) to the second chamber (14) and a second pipe (50) configured to operate as a flush in such a way as to transfer a liquid present in the second chamber (14) to the lower first chamber (12) when the liquid reaches a given height in the second chamber (14), the second pipe (50) having the shape of an inverted U with an elbow section (56), a first end (52) which opens into the second chamber (14) close to the bottom (24) thereof, and a second end which opens into the first chamber (12).

Description

DEVICE FOR REALIZING FERMENTATION TESTS WITH A SMALL VOLUME OF

MUST

The present invention relates to a device for carrying out fermentation tests with a small volume of must. This device is particularly suitable for the vinification of a small volume of must called nano-vinification.

A winemaking process aims to transform the must of black grapes (mixture of berries and juice) introduced into a vat of red wine. This process comprises different phases, including alcoholic fermentation and various operations, such as winding.

During the alcoholic fermentation, yeasts progressively transform the sugar contained in the berries into alcohol. During this phase, solid particles such as grape skins tend to rise to the surface of the must and form a pomace cap that isolates the wort from the gaseous phase present in the vat above the cap. Therefore, it is necessary to carry out reassembly operations during the vinification. This winding operation aims to extract the must in the lower part of the tank and then pour it on the cap of marc. This operation, realized thanks to a pump, aims to homogenize the tank, to optimize the extraction of certain elements of the berries (tannins, precursors of aroma, odorous molecules) which are present mainly in the skins of the grapes, to humidify the hat of marc to prevent oxidation and contamination by microorganisms. Under certain circumstances, this operation can be coupled with an introduction of oxygen (reassembly with oxygenation).

During the vinification in red, which usually includes the alcoholic fermentation phase and the malolactic fermentation phase, are associated various operations: reassembling, pressing, draining, etc. Another operation called pigeage consists of pressing the marc hat into must during fermentation or wine to promote the extraction of film components (phenolic compounds, flavorings).

At the end of the vinification process, the properties of the wine, and more particularly its organoleptic characteristics, will thus vary depending in particular on initial characteristics of the grapes (stage of maturity, richness in various compounds such as sugars, acids, phenolic compounds, aromas and aroma precursors ...), as well as depending on the conditions (temperature, hygrometry, duration, ...) in which the different operations and phases are operated.

According to another point, the winemaker has many oenological products and winemaking equipment that offer him the opportunity to infinitely vary the methods of winemaking. In order to improve the quality of the wines obtained and / or to evaluate the contribution of these new oenological products and winemaking materials, tests are conducted to optimize the winemaking process.

These tests carried out in tanks of small capacities, called micro-vinifications, must make it possible to simulate vinification carried out in large tanks, from several tens to several hundreds of hectoliters.

The tanks used for micro-vinification each comprise a container closed by a lid and have a capacity of the order of 25 to 100 L, which represents about 50 to 160 kg of grapes. Below this capacity, the results obtained during winemaking tests are generally not representative, fluctuations being observed in the sensory characteristics of the wines and their compositions, particularly their phenolic and aromatic compositions. According to another point, the punching operations are necessary to promote the extraction of the film compounds during the vinification.

Unlike large volumes that can easily control operating parameters due to inertia and latency, for small volumes, changes can be fast, uncontrolled and significantly impacting. Thus, winding operations that are carried out in the open air can generate due to a large supply of oxygen uncontrolled effects that necessarily have an impact on the experimental results. It is the same for all operations that require opening the tank, for example to take a sample or place a probe inside the tank. In addition, extraction by pigeage having an impact on the extraction of phenolic compounds (anthocyanins, tannins), the phenolic composition of wines thus elaborated is different from that of wines elaborated on a large scale in winemaking cellars. Because of the non-repeatability of certain operations, such as manual reassembly or punching operations, which are therefore not performed in a reproducible manner, each experiment is duplicated three times for the experimental results to be validated.

Given the existing methods and tools, carrying out winemaking tests requires a large volume of harvest, of the order of several hundred kilograms to be able to vary many experimental variables and perform each experiment in triplicate. This solution is not satisfactory because it leads to use a large volume of lost grapes that will not be marketed.

In practice, winemaking trials are usually done with a small volume of grapes to avoid losing too much of the harvest. Therefore, it is necessary to make concessions on the number of experimental variables, the number of repetitions and / or the number and frequency of measurements. In view of these concessions, the reliability of vinification tests carried out with small volumes is therefore debatable.

The problems encountered for winemaking tests are recurrent to other fermentations.

Also, the present invention aims to overcome the drawbacks of the prior art by providing a device for carrying out fermentation tests with a small volume of must which improves the reliability and repeatability of the tests, while reducing the amount of material. necessary to achieve them.

For this purpose, the subject of the invention is a device for carrying out fermentation tests, said device comprising a first chamber configured to receive wort and being characterized in that it comprises a second chamber positioned above the first chamber. and an automatic winding system which comprises a first conduit configured to raise a liquid from the first chamber to the second chamber and a second conduit configured to perform the flushing function so as to transfer a liquid in the second chamber to the first chamber when the liquid reaches a given height in the second chamber, the second conduit having an inverted U shape with a bent portion, a first end that opens into the second chamber near its bottom and a second end that opens into the second chamber; the first room. This solution allows for reassembly operations without the need to open one of the two rooms. In addition, it is no longer necessary to perform punching operations to obtain the extraction of the film compounds. By limiting the risk of contamination of the must, this solution makes it possible to obtain representative results of a large-scale fermentation.

Preferably, the bottom of the second chamber preferably comprises a recess in which opens the second end of the second conduit, said second end opening at a lower level than the bottom. Thus, almost all the liquid contained in the second chamber is transferred to the first chamber during its emptying. Only a very small volume of liquid remains in the second chamber after emptying.

Advantageously, the bent portion of the second conduit is separated from the bottom of the second chamber by a distance equal to the given height of the liquid in said second chamber to automatically trigger its emptying.

Preferably, the second conduit comprises a check valve which allows the flow of fluid from the second chamber to the first chamber and prevents the flow of fluid from the first chamber to the second chamber. This configuration allows the pressure in the first chamber to increase to cause the refilling of the liquid from the first chamber to the second chamber.

According to another configuration of the invention, the first and second chambers each have a capacity of less than or equal to 10 L. Thanks to the device of the invention, it is possible to obtain convincing results with a small volume of must. Therefore, it is possible, at constant volume of must, to perform a greater number of experiments.

Advantageously, the device comprises a means for dispersing the liquid leaving the second conduit, configured to break the jet of the liquid and distribute it over a large area. According to one embodiment, the device comprises:

a first container with a bottom and at least one side wall,

a second container with a bottom and at least one side wall, the second container being configured to cooperate with the side wall of the first container so as to define the first chamber,

- A cover configured to cooperate with the side wall of the second container so as to define the second chamber. Advantageously, each chamber comprises an orifice which makes it possible to communicate said chamber with the outside and which is positioned so as to open at the bottom of said chamber. These orifices allow in particular a flow of the liquid to the outside of the device.

Preferably, the device comprises an orifice which makes it possible to communicate the inside of the first chamber with the outside and which opens at the top of said first chamber. This orifice makes it possible in particular to inject a gas into the first chamber in order to inert it or cause the liquid to be reassembled towards the second chamber.

The invention also relates to an installation for carrying out fermentation tests, which is characterized in that it comprises at least one device according to the invention, an inert gas tank and a control station configured to control the injection of inert gas into the first chamber of said device. This solution automates the triggering of winding operations.

Advantageously, this installation comprises at least one device for carrying out fermentation tests which is equipped with at least one sensor connected to a control station in order to acquire data continuously and automatically.

Finally, the invention also relates to a method of operating a device according to the invention which is characterized in that it comprises the steps of:

- filling the first chamber with must,

- closing the first chamber,

- reassembly of the liquid present in the first chamber to the second chamber through an increase in pressure in said first chamber,

- Draining the second chamber to the first chamber when the liquid reaches a given height in the second chamber.

According to one procedure, an inert gas is injected into the first chamber to cause the pressure increase in said first chamber.

Other features and advantages will become apparent from the following description of the invention, a description given by way of example only, with reference to the appended drawings in which:

FIG. 1 is a perspective view of a winemaking device which illustrates one embodiment of the invention,

FIG. 2 is a side view of a winemaking device which illustrates the invention, FIG. 3 is a diagrammatic section of a winemaking device which illustrates the invention,

FIG. 4 is a perspective view illustrating a first container of the vinification device of FIG.

FIG. 5 is a perspective view illustrating a second container of the vinification device of FIG. 1,

FIG. 6 is a perspective view illustrating in detail a valve,

FIGS. 7A to 7E are diagrams that illustrate the operation of the vinification device visible in FIG. 1,

FIG. 8 is a diagram which shows the repeatability of the tests on several tanks.

In Figures 1 to 5, there is shown in 10 a device for performing winemaking tests. This device 10 comprises two chambers, a lower chamber 12 and an upper chamber 14 superimposed on one another.

Advantageously, the device 10 comprises:

a first container 16 (visible in FIG. 4) with a bottom 18 and at least one side wall 20,

a second container 22 (visible in FIG. 5) with a bottom 24 and at least one side wall 26, the bottom 24 of the second container 22 being configured to close the first container 16,

a cover 28 configured to close the second container 22.

Thus, the first container 16 and the bottom 24 of the second container 22 delimit the lower chamber 12, the second container 22 and the lid 28 define the upper chamber 14. The bottom 24 of the second container 22 forms a wall separating the two lower chambers. 12 and above 14. For the remainder of the description, the bottom 24 is also called partition wall 24.

A first locking / unlocking system 30 (visible in FIG. 2), like several flanges, for example, is provided for securing the second container 22 to the first container 16. This locking / unlocking system 30 is configured to occupy a locked state in which the second container 22 is secured to the first container 16 so as to obtain a lower sealed chamber 12 despite a possible overpressure in said lower chamber 12 and an unlocked state in which it is possible to detach the second container 22 of the first container 16 to access the lower chamber 12 to fill or empty for example.

In the same manner, a second locking / unlocking system 32 (visible in FIG. 2) is provided for securing the lid 28 to the second container 22. This locking / unlocking system 32 is configured to occupy a locked state in which the lid 28 is secured to the second container 22 so as to obtain a sealed upper chamber 14 and an unlocked state in which it is possible to separate the lid 28 of the second container 22 in order to access the upper chamber 14.

The first and second locking / unlocking systems 30 and 32 may be identical.

Preferably, the device 10 comprises sealing means interposed between the first container 16 and the second container 22 to enhance the sealing of the lower chamber 12 and / or sealing means interposed between the second container 22 and the lid 28 to enhance the sealing of the upper chamber 14. According to one embodiment, the sealing means are annular seals, for example flat or O-rings. In one configuration, the containers 16 and 22 have a circular section. As a result, the sidewalls 20 and 26 are each in the form of a cylinder. Of course, the invention is not limited to this section for containers.

The side wall 20 of the first container 16 has an upper edge with shapes that cooperate with the second container 22. According to one embodiment, the upper edge of the side wall 20 of the first container 16 comprises a flange 34 (visible in FIG.

4). In addition, the second container 22 comprises a flange 36 (visible in FIG.

5) configured to be pressed against the collar 34 of the first container 16. In order to obtain a sealed lower chamber 12, sealing means (such as for example an annular seal) are interposed between the two collars 34 and 36 and the first locking / unlocking system 30 is positioned to maintain the two flanges 34 and 36 pressed against each other.

Preferably, as illustrated in Figure 5, the second container 22 comprises an extension 38, under the bottom 24 and in the continuity of the side wall 26, the lower edge is configured to cooperate with the upper edge of the side wall 20 of the first container 16. According to one embodiment, the lower edge of the extension 38 (visible on Figure 5) comprises a flange 36 which cooperates with the flange 34 of the first container 16 to ensure the junction between the containers 16 and 22.

The side wall 26 of the second container 22 has an upper edge with shapes that cooperate with the lid 28. According to one embodiment, the upper edge of the side wall 26 of the second container 22 comprises a flange 40 (visible in FIG. ). In addition, the cover 28 comprises a flange 42 configured to be pressed against the collar 40 of the second container 22. In order to obtain a sealed upper chamber 14, sealing means (such as for example an annular seal) are interposed between the two flanges 40 and 42 and the second locking / unlocking system 32 is positioned to maintain the two flanges 40 and 42 pressed against each other. In terms of size, the lower chamber 12 and upper 14 have substantially the same capacity.

According to a feature of the invention, each chamber 12 or 14 has a capacity of less than or equal to 10 L. Preferably, each chamber 12 or 14 has a capacity of about 3 to 5 L which corresponds to about 7 to 10 Kg of grapes to carry out a vinification test with the device according to the invention. Due to the small volume of must necessary, this device allows to perform nano-vinification.

To give an order of magnitude, each chamber has a diameter of about 20 cm and a height of about 20 cm.

According to another characteristic of the invention, the device 10 comprises an automatic winding mechanism.

This winding mechanism comprises a first conduit 44 which passes through the partition wall 24 and which makes it possible to communicate the two lower chambers 12 and upper 14. This first conduit 44 is configured to raise a liquid from the lower chamber 12 to the upper chamber 14 For this purpose, the first conduit 44 comprises a lower end 46 which opens near the bottom 18 of the lower chamber 12 and an upper end 48 which opens into the upper part of the upper chamber 14 near the cover 28. Advantageously, the lower end 46 is slightly flared downward as illustrated in Figure 5 to promote the admission of the liquid present in the lower chamber 12. Preferably, this lower end 46 comprises a grid to prevent the introduction of solid elements in the first conduit 44. Thus, this lower end 46 performs the function of strainer. According to one embodiment, the first conduit 44 is rectilinear. It is connected to the bottom 24 of the second container 22.

In addition to the first conduit 44, the winding mechanism comprises a second conduit 50 which passes through the partition wall 24 and which makes it possible to communicate the two lower chambers 12 and upper 14. This second conduit 50 is configured to perform the hunting function 'water. Thus, it automatically empties the upper chamber 14 and the transfer of the liquid present in said upper chamber 14 to the lower chamber 12. For this purpose, the second conduit 50 has an inverted U-shape with a first end 52 which opens into the upper chamber 14 near the bottom 24 of the upper chamber 14 and a second end 54 which opens into the lower chamber 12 just below the bottom 24.

According to one embodiment, the second duct 50 comprises two parallel rectilinear portions, connected by a bent portion 56. This second duct 50 is connected to the bottom 24 of the second container 22.

The distance between the bent portion 56 of the second conduit 50 and the bottom 24 is adjusted to define the necessary liquid height in the upper chamber 14 to automatically trigger the emptying of the upper chamber 14. Thus, as soon as the height of liquid in the upper chamber 14 reaches the bent portion 56, the emptying of the upper chamber 14 is automatically triggered.

Advantageously, the bottom 24 of the second container 22 comprises a recess 58 (visible in Figures 1 and 7E) in which the second end 54 opens, said second end opening at a lower level than the bottom 24 as shown in Figure 7E. To give an order of magnitude, this hollow has a depth of about one centimeter and a diameter of about 4 cm. This configuration makes it possible to keep only a very small volume of liquid in the upper chamber 14 after emptying. Thus, almost all the liquid present in the upper chamber 14 is transferred to the lower chamber 12 after emptying.

Preferably, the second conduit 50 comprises a non-return valve 60 (visible in FIGS. 1 and 7A) positioned just upstream of the second end 54. This non-return valve 60 allows the flow of a fluid from the upper chamber 14 towards the lower chamber 12 and prevents the flow of fluid from the lower chamber 12 to the upper chamber 14. This configuration provides a pressure in the lower chamber 12 sufficient to cause the flow of wort present in the lower chamber 12 to the upper chamber 14 via the first conduit 44.

Advantageously, the device 10 comprises a valve 62 which passes through the bottom 24 and makes it possible to make the two chambers 12 and 14 communicate. This valve 62, illustrated in detail in FIG. 6, is configured to allow the flow of the lower chamber 12 to the upper chamber 14 when the pressure in the lower chamber 12 exceeds a given threshold. This valve 62 provides a safety function and is triggered in case of excessive pressure in the lower chamber 12.

According to another characteristic, the device 10 comprises a means 64 for dispersing the liquid leaving the second conduit 50, as illustrated in FIG. 5. This dispersion means 64 is positioned just after the second end 54 of the second conduit 50. breaking the jet of the liquid and distributing the liquid over a large surface, especially over the entire surface of the cap present in the lower chamber 12.

According to one embodiment, this dispersion means 64 has a conical shape with a vertex oriented towards the upper chamber 14. Preferably, the conical shape has a peripheral edge with a plurality of radially extending branches, long limbs and branches. short, which are arranged alternately. Of course, the invention is not limited to this embodiment to promote the dispersion of the liquid leaving the second conduit 50 over the entire surface of the cap.

Advantageously, the device 10 comprises a first orifice 66 which makes it possible to communicate the interior of the lower chamber 12 with the outside of the device 10. This first orifice 66 comprises a valve 68 to allow or not the passage of a fluid to through the first orifice 66. The first orifice 66 is positioned so as to open in the upper part of the lower chamber 12. This first orifice 66 makes it possible to introduce or extract a gas inside the lower chamber 12, in particular to provoke the reassembly of the wort of the lower chamber 12 towards the upper chamber 14 or to inert the contents of the lower chamber 12.

The device 10 comprises a second orifice 70 which makes it possible to communicate the interior of the lower chamber 12 with the outside of the device 10. This second orifice 70 comprises a valve 72 to allow or not the passage of a fluid through the second orifice 70. The second orifice 70 is positioned so as to open at the bottom of the chamber lower 12. This second orifice 70 allows in particular a flow of the liquid present in the lower chamber 12 to the outside.

The device 10 comprises a third orifice 74 which makes it possible to communicate the interior of the upper chamber 14 with the outside of the device 10. This third orifice 74 comprises a valve 76 to allow or not the passage of a fluid through the third orifice 74. The third orifice 74 is positioned to open in the lower part of the upper chamber 14. This third orifice 74 allows in particular a flow of the liquid present in the upper chamber 14 to the outside.

These orifices 66, 70 and 74 can also be used to take samples inside the two chambers without having to open them.

Advantageously, the lid 28 comprises an aseptic bung 78 used to take samples in the upper chamber 14.

The device 10 may comprise other elements for taking samples in the chambers 12 and 14 without having to open them. Thus, for at least one of the two chambers 12, 14, the side wall 20 and / or 26 comprises a sampling septum.

Preferably, for at least one of the two chambers 12, 14, the side wall 20 and / or 26 comprises at least part of a transparent material to visualize the interior of the chambers 12 and 14. Thus, at least one of the sidewalls 20, 26 comprises a porthole. According to another characteristic, the device 10 comprises a stirrer 80 for breaking the cap present in the lower chamber 12. According to one embodiment, this stirrer 80 comprises blades 82 supported by an axis of rotation 84, approximately horizontal which passes through apart from the lower chamber 12. A crank 86 is provided at one end of the axis of rotation 84 to drive it in rotation manually.

According to another embodiment, the stirrer 80 comprises blades supported by an approximately vertical axis of rotation which passes through the bottom 24. According to one configuration, this vertical axis of rotation is movable in translation in a vertical direction.

The operating mode of the device 10 is described with reference to FIGS. 7A to 7E.

The second container 22 being disconnected from the first container 16, the lower chamber 12 is filled with berries and grape juice. Following, the cover 28 is secured to the second container 22 through the second locking / unlocking system 32 and the second container 22 is secured to the first container 16 through the first system of In this configuration, as illustrated in FIG. 7A, the two lower chambers 12 and upper 14 are closed in a substantially watertight manner. The grape must is surmounted by a gaseous phase 88 called sky at a pressure P1 which is equal to the atmospheric pressure just after the closing of the chambers. The upper chamber 14 contains only a gaseous phase 90 at a pressure P2 which is equal to the atmospheric pressure.

During the vinification, the transformation of the sugar into alcohol generates a release of carbon dioxide which accumulates in the sky 88. During this phase, solid elements accumulate in the upper part of the must 92 and form a pomace hat 94 .

All the valves 68, 72, 76 being in the closed position, the pressure in the sky 88 increases. Since the sky pressure P1 'is greater than the pressure P2 of the gas phase 90 of the upper chamber 14, the wort 92 rises the first pipe 44 to be discharged into the upper chamber 14, as illustrated in FIG. 7B. The upper chamber 14 comprises a liquid phase 96, the upper level 98 rises gradually as the winding operation. After a while, almost all of the liquid in the lower chamber 12 has been transferred to the upper chamber 14. As shown in FIG. 7C, only the coffee cap 94 remains in the lower chamber 12 In the upper chamber 14, the level 98 of the liquid phase 96 reaches the top of the elbow 56 of the second duct 50. As a result of a flushing effect, as shown in FIG. 7D, the upper chamber 14 is empty. and the liquid phase 96 is transferred to the lower chamber 12. The liquid is then poured over the coffee cap 94. The optimized shape of the liquid dispersion means 64 makes it possible to obtain a homogeneous watering of the coffee cap 94. At the end of this phase of flow to the lower chamber 12, all the must is contained in the lower chamber 12 and the upper chamber 14 is again empty. Only a very small volume of liquid remains at the level of the depression 58, as illustrated in FIG. 7E.

To obtain the reassembly of the must from the lower chamber 12 to the upper chamber 14, it is possible to use the release of carbon dioxide produced during the alcoholic fermentation, as previously described.

Alternatively, it is possible to inject into the sky 88 an inert gas via the first orifice 66.

According to an embodiment illustrated in FIG. 2, an installation for carrying out winemaking tests comprises at least one vinification device 10 according to the invention, a an inert gas tank 100 connected via a conduit 102 to the first orifice 66, a valve 104 which controls the flow of the inert gas injected into the lower chamber 12 and a control station 106, such as a computer or an automaton for example, used to control the valve 104 and control the triggering of the reassembly operation. This configuration makes it possible to automate winding operations.

Preferably, the same tank of inert gas 100 is connected to several winemaking devices 10 and the same control station 106 is used to control the winding operations in the various winemaking devices.

According to another characteristic, a device 10 according to the invention can be equipped with a thermoregulation system, with one or more sensors (density, dissolved gas). The different sensors are preferably connected to a control station, such as a computer for example, to acquire data continuously and automatically. In addition, the thermoregulation system can be controlled by the same control station as the winding operation.

According to the invention, the reassembly and measurement operations are performed in an automated manner without the need to open the nano-vinification device. Consequently, the results obtained with a small volume of must are representative of a large-scale vinification.

As illustrated in FIG. 8, the repeatability between the tests is very good. The monitoring of the density Mv over time in tanks C1 to C9 shows that the values are identical for all the tanks over time.

Although described applied to winemaking, the device according to the invention can be used to carry out tests for other types of fermentation.

The advantages provided by the invention are as follows:

Insofar as it is not necessary to open one of the two chambers 12 and 14 to perform the pumping or sampling, the risk of contamination (by an uncontrolled supply of oxygen, by microorganisms ) is very limited. Consequently, the results obtained are representative of those obtained during a large-scale vinification.

The winemaking device makes it possible to carry out vinification tests with a small volume of material. Therefore, it is possible to multiply the experimental conditions (number of experimental variables, number of repetitions, number and frequency of measurements) from a much lower quantity of grapes than for the prior art.

According to another advantage, the winding operations and measurement taking being automated, the artifacts related to these manipulations are reduced. Consequently, the repeatability of the tests is greatly increased. Thanks to the repeatability of the tests, it is no longer necessary to perform each experiment in triplicate.

The automation of measurement and reassembly operations reduces the labor required to perform all these operations so that it is possible, in a short period of time (duration of the harvest), to multiply the conditions experimental. According to another advantage, the automation of sampling allows a more continuous monitoring (possible measurements on nights and weekends) on a larger number of winemaking devices.

Finally, the devices according to the invention being less bulky, it is possible to store a larger number in a room with a controlled temperature.

Claims

Apparatus for carrying out fermentation tests, said device comprising a first chamber (12) configured to receive wort, characterized in that it comprises a second chamber (14) positioned above the first chamber (14) and an automatic winding system that includes a first conduit (44) configured to raise a liquid from the first chamber (12) to the second chamber (14) and a second conduit (50) configured to perform the flush function of transferring a liquid present in the second chamber (14) to the first chamber (12) when the liquid reaches a given height in the second chamber (14), the second conduit (50) having an inverted U-shape with a portion angled (56), a first end (52) which opens into the second chamber (14) near its bottom (24) and a second end (54) which opens into the first chamber (12).

2. Device according to claim 1, characterized in that the bottom (24) of the second chamber (14) comprises a recess (58) in which opens the second end (54) of the second conduit (50), said second end ( 54) opening at a lower level than the bottom (24).

3. Device according to claim 1 or 2, characterized in that the bent portion (56) of the second conduit (50) is separated from the bottom (24) of the second chamber (14) by a distance equal to the given height of the liquid in said second chamber (14) to automatically trigger the emptying of the second chamber (14).

4. Device according to one of the preceding claims, characterized in that the second conduit (50) comprises a non-return valve (60) which allows the flow of a fluid from the second chamber (14) to the first chamber (12). and prevents the flow of fluid from the first chamber (12) to the second chamber (14).

5. Device according to one of the preceding claims, characterized in that the first and second chambers (12, 14) each have a capacity less than or equal to

10 L.

6. Device according to one of the preceding claims, characterized in that it comprises a means (64) for dispersing the liquid exiting the second conduit (50), configured to break the jet of the liquid and spread over a large area.

7. Device according to one of the preceding claims, characterized in that it comprises a stirrer (80) in the first chamber (12).

8. Device according to one of the preceding claims, characterized in that it comprises:

a first container (16) with a bottom (18) and at least one side wall (20), a second container (22) with a bottom (24) and at least one side wall (26), the second container (22) ) being configured to cooperate with the side wall (20) of the first container (16) so as to define the first chamber (12),

a cover (28) configured to cooperate with the side wall (26) of the second container (22) so as to define the second chamber (14).

9. Device according to one of the preceding claims, characterized in that each chamber (12, 14) comprises an orifice (70, 74) which makes it possible to communicate said chamber (12, 14) with the outside and which is positioned so as to open at the bottom of said chamber (12, 14).

10. Device according to one of the preceding claims, characterized in that it comprises an orifice (66) which allows to communicate the interior of the first chamber (12) with the outside and which opens in the upper part of said first room (12).

11. Installation for carrying out fermentation tests, characterized in that it comprises at least one device (10) according to one of the preceding claims, an inert gas tank (100) and a control station (106). configured to drive the injection of inert gas into the first chamber of said device.

12. Installation for carrying out fermentation tests, characterized in that it comprises at least one device (10) according to one of claims 1 to 11 equipped with at least one sensor connected to a control station in order to acquire data continuously and automatically.

13. The method of operation of a device according to one of claims 1 to 10, characterized in that it comprises the steps of:

filling the first chamber (12) with must,

closing the first chamber (12),

- reassembly of the liquid present in the first chamber (12) to the second chamber (14) by increasing pressure in said first chamber (12), draining the second chamber (14) to the first chamber (12) when the liquid reaches a given height in the second chamber (14).

14. The method of claim 13, characterized in that an inert gas is injected into the first chamber (12) to cause the pressure increase in said first chamber (12).