Ultrasonic barrel reconditioning process

Abstract

METHOD FOR RECONDITIONING BARRELS BY ULTRASONIC MACHINERY A method (500) for reconditioning a used barrel (100) comprising staves (10) and two heads (30), the assembled staves forming a shell (50), said method comprising: a step (510) of dismantling the heads to isolate the shell; a step (520) of planing the inner faces (11) of the shell to remove a layer penetrated by substances previously stored in the barrel; a step (540) of heating the shell; and a step (550) of cleaning the inner faces of the barrel by ultrasound, followed by an optional step (560) of vaporizing tannins onto the inner faces of the barrel when the latter is intended for aging wine. Figure for the abstract: Figure 2

Description

Title of the invention: Method for reconditioning barrels using ultrasound Technical field

[0001] The present invention belongs to the field of barrels, in particular barrel-type barrels used for raising and transporting alcoholic beverages such as wine, and sometimes for preserving other liquid or solid food products. The present invention relates more particularly to a method for reconditioning barrels by ultrasound.

[0002] The present invention applies mainly, but not exclusively, to wine aging barrels. State of the art

[0003] Barrels have been known since ancient times, with the bending of hot wood. This very practical container was used and continues to be used today for the conservation or aging as well as the transport of various food products, especially liquids, including wine mainly.

[0004] Despite significant advances in food technology, and more specifically in winemaking, replacing the traditional wooden barrel seems difficult to imagine. Indeed, in addition to its crucial role in wine aging, this container remains emblematic and rich in a history that recalls great epics of commerce, and even of science when, for example, it was used to name the famous "barrel burst" experiment that gave rise to Pascal's principle in hydrostatics.

[0005] To be reused in good conditions, the barrels must be reconditioned after a certain number of uses. Indeed, in the case of wine aging, the aromatic contribution of the barrels decreases with consecutive vinifications.

[0006] There are many reconditioning processes to make used barrels reusable. Most of these processes use water jet cleaning followed by chemical treatments which can sometimes cause the dissolution of additives in the wine, with the risk of altering the quality of the wine.

[0007] Other processes use steaming by injecting pressurized steam. The steam condenses on the internal walls of the barrel, which both raises their temperature, to the point of destroying the ferments, and rinses them. However, steam has the disadvantage of degrading the aromatic compounds in the wood and therefore compromising the aging of the wine.

[0008] Other processes using sandblasting, planing, microwave treatment are known, but can dry out the barrels without eliminating the bacteria that colonize the pores of the wood deep down.

[0009] Most often, the various aforementioned techniques are combined to obtain a reconditioning process adapted to the specificities of each type of barrel.

[0010] For example, WO2008054707 describes methods for reconditioning a barrel previously used to store a given substance, comprising the steps of determining barrel material-specific cutting parameters for controlled cutting of the barrel material; removing a desired depth of the barrel material using an automated high-pressure water jet cutting device; testing for residue of the substance using a detection device; optionally spraying a dissolving agent; and repeating the removal and testing steps if the presence of the substance in or on the barrel is detected.

[0011] The use of ultrasound for cleaning barrels is also known. However, ultrasound alone is not very effective for descaling and requires extensive prior cleaning by mechanical action.

[0012] Document FR2975312 describes a method for cleaning, descaling and disinfecting barrels, comprising drilling a bottom of the barrel, internal cleaning by high-pressure hot water jet, finishing the cleaning by ultrasound and type C germicidal ultraviolet rays, rinsing followed by draining, and wicking with sulfur dioxide (SO2).

[0013] This solution corresponds to a very thorough physical and chemical cleaning of the walls, but does not guarantee a deep cleaning when the walls are well penetrated by the wine, because it does not propose any removal of material on said walls. Presentation of the invention

[0014] The present invention aims to overcome the drawbacks of the prior art, set out above, by proposing an innovative solution for reconditioning without the slightest chemical treatment, which is economical and particularly eco-responsible.

[0015] To this end, the present invention relates to a method for reconditioning a used barrel, in particular for aging wine, comprising staves and two bottoms, the assembled staves forming a shell, said method comprising: • a step of dismantling the bottoms to isolate the shell; and • a step of planing the internal faces of the hull to remove a layer penetrated by substances previously stored in the barrel.

[0016] This method is remarkable in that it comprises, after the aforementioned steps: • a hull heating step; and • a step of cleaning the internal faces of the barrel using ultrasound.

[0017] The reconditioning process according to the invention thus makes it possible to increase the lifespan of the treated barrels while preserving their organoleptic potential.

[0018] Advantageously, the internal faces of the bottoms of the barrel can also be planed.

[0019] According to one embodiment, the method further comprises a step of reassembling the bottoms just before the ultrasonic cleaning step.

[0020] More particularly, the ultrasonic cleaning step can be carried out in the reassembled barrel, through a bung hole in said barrel.

[0021] According to a particular embodiment, the planing step is automated and consists of rotating the shell around its axis of revolution and coming into contact with the internal faces of said shell with a planing head movable along at least two axes.

[0022] Advantageously, the ultrasonic cleaning step is carried out with high-power ultrasound with a frequency of 20 kHz for example.

[0023] According to one embodiment, the method further comprises a final step of vaporizing tannins on the internal faces of the barrel, for health reasons, especially when the reconditioned barrel is intended to be transported for long periods before being filled.

[0024] Advantageously, the heating step and the ultrasonic cleaning step are carried out in this order to avoid additional disassembly and reassembly.

[0025] The fundamental concepts of the invention having just been set out in their most elementary form, other details and characteristics will emerge more clearly on reading the description which follows and with reference to the appended drawings, giving by way of non-limiting example an embodiment of a method for reconditioning a barrel by ultrasound in accordance with the principles of the invention. Presentation of the drawings

[0026] The figures are given purely for illustrative purposes for a better understanding of the invention without limiting its scope. The various elements are represented schematically. Throughout the figures, identical or equivalent elements bear the same numerical reference.

[0027] It is thus illustrated in:

[0028] [Fig-1]: a perspective view of a barrel for implementing the invention;

[0029] [Fig.2]: a synopsis of the main stages of a reconditioning process of ultrasonic barrel according to one embodiment of the invention;

[0030] [Fig.3]: the step of dismantling the funds;

[0031] [Fig.4]: the automatic planing step of the hull;

[0032] [Fig.5]: the barrel heating stage;

[0033] [Fig.6]: the step of cleaning the barrel by ultrasound;

[0034] [Fig.7]: the optional step of vaporizing tannins. Detailed description of embodiments

[0035] In the embodiment described below, reference is made to a method for reconditioning barrels by ultrasound, intended mainly for wine aging barrels. This non-limiting example is given for a better understanding of the invention and does not exclude the use of such a reconditioning method on other wooden containers, in particular various wooden barrels.

[0036] In the present description, the term "barrel" designates a wooden container with symmetry of revolution, swollen in its middle, made up of curved staves assembled and held by generally metal circles, closed by two flat bottoms, and used to store / raise and transport liquids for consumption, in particular alcoholic drinks such as wine.

[0037] [Fig.l] represents a “traditional” barrel 100, suitable for implementing the invention, comprising a plurality of staves 10 assembled by riveted circles 20 and two bottoms 30, of which only the upper bottom is visible in the figure. The barrel 100 can be filled and emptied through a bung hole 15 provided in its main stave.

[0038] The barrel 100, when emptied of its contents (wine for example), must be cleaned in order to avoid the appearance of mold on its internal faces, in particular acetic bacteria. In addition, after a certain number of vinifications, it is necessary to completely recondition the barrel 100 to make it reusable. Indeed, in the case of wine aging, repeated vinifications in the same barrel greatly reduce, or even eliminate, the exchanges between the wood and the wine, which are very important in the winemaking process.

[0039] For this purpose, the barrel 100 can be reconditioned by implementing an ultrasonic reconditioning method according to the invention.

[0040] [Fig.2] represents the main steps of a method of reconditioning 500 a barrel, said method comprising: • an initial step 510 of dismantling the bottoms to isolate the hull; • a step 521 of planing the internal faces of the hull; • an optional step 522 of sanding the bottoms for a better finish; • a step 530 of heating the barrel; • a step 540 of reassembling the bottoms to reconstitute the barrel; • a step 550 of cleaning the barrel by ultrasound; and • an optional step 560 of vaporization of tannins inside the barrel.

[0041] Of course, the reconditioning process 500 is implemented after rinsing, draining and drying the barrel, to prepare the working steps of the wood, namely planing and sanding.

[0042] Step 510 of dismantling the bottoms consists of removing the bottoms to isolate the hull, the hull being made up of the assembled staves, and can be carried out by a usual method known to those skilled in the art, in particular coopers. This separation then makes it possible to treat the hull and each bottom individually during steps 521 of planing the internal faces of the hull and 522 of sanding the bottoms.

[0043] [Fig. 3] shows schematically the step 510 of dismantling the bottoms 30 to isolate the hull 50.

[0044] Then, the step 521 of planing the internal faces of the hull consists of planing the internal face of each stave in order to remove a layer penetrated by the wine. This makes it possible to eliminate the ethanol present in the wood before ultrasonic cleaning.

[0045] Planing can be done manually or automatically by means of any suitable tool or system.

[0046] [Fig. 4] represents an embodiment in which the step 521 of planing the hull 50 is carried out automatically by positioning said hull on rotation means 211 actuated by motors and by introducing a movable arm 212 provided with a planing head 213 inside the hull to come into contact with the internal faces 11 of the staves. The planing head 213 is preferably oriented downwards to benefit from the effect of gravity during planing. This automated planing system can be controlled by a programmable controller making it possible to adjust the rotation speed of the hulls, the position of the arm and other functional parameters. According to this example, the hull 50 is rotated around its axis of revolution, parallel to a horizontal axis Y of the system of axes (X, Y, Z) represented. The planing arm 212 is movable in translation along the horizontal axis Y and the vertical axis Z.Thus, these two translational movements of the planing head 213 make it possible to cover the entire length of the shell 50 and to match the bulge thereof respectively.

[0047] The planing is then done by successive circumferential strips over the entire length of the shell 50.

[0048] Of course, the planing of the internal faces of the staves can be done differently, for example by dismantling the staves and planing them individually using a traditional plane.

[0049] The planing can also concern the internal faces of the bottoms 30 in certain cases, in particular when the reconditioned barrels will be intended for white wine after they have been used to age red wine.

[0050] However, not planing the bottoms 30 is preferred to preserve a tartaric film and avoid the wine coming into contact with virgin wood.

[0051] Step 522 of sanding the bottoms 30 is optional and consists of sanding the external face of each bottom 30 to eliminate traces of wear and obtain a better finishing the reconditioned barrel. This step can be carried out at any time during the process.

[0052] The planing can concern both staves 10 and bottoms 30 due to the penetration of the wine into almost all the internal walls of the barrel. Depending on the storage position of the barrel, vertical or horizontal, the penetration of the wine into the wood can be greater either in the staves or in the lower bottom of said barrel.

[0053] The planing step 521 thus constitutes a first cleaning (stripping) of the barrel by removing material, which makes it possible to remove residual deposits but also the layers of wood penetrated by the ethanol.

[0054] However, mold may remain deep in the pores of planed wood.

[0055] The following steps therefore allow the barrel to be thoroughly disinfected.

[0056] Before reassembling the barrel for ultrasonic cleaning, it is more advisable to heat the hull to avoid having to disassemble the bottoms and reassemble them once more. Therefore, it is preferable to carry out steps 530 of heating, 540 of reassembling the bottoms and 550 of ultrasonic cleaning in this order.

[0057] [Fig. 5] shows schematically the step 530 of heating the hull 50 which allows the internal faces of the staves to be “leathered” using a flame or embers F in order to soften the wood fiber and regenerate its organoleptic potential. Indeed, the heating step is important insofar as the step 510 of dismantling the bottoms and the step 521 of planing the hull have the consequence of annihilating the effects of the initial heating which accompanied the manufacture of the barrel.

[0058] Step 540 of reassembling the bottoms consists of replacing the bottoms 30 on the heated shell 50 to allow the reconstituted barrel to be cleaned by ultrasound.

[0059] [Fig.6] shows schematically the step 550 of ultrasonic cleaning which consists firstly in completely filling the barrel 100 with hot water and, secondly, in generating ultrasonic waves in the water to create a cavitation phenomenon.

[0060] According to the illustrated embodiment, the filling of the barrel 100 is done by a suitable filling means 220, such as a lance or a pipe connected to a hot water tank, introduced into the bung hole.

[0061] The filling water may, for example, be at a temperature of approximately 60°C and under pressure to promote its penetration into the pores of the wood.

[0062] Hot filling water can have a preliminary cleaning effect, particularly on fatty substances which emulsify and disintegrate more easily under the effect of heat.

[0063] After filling the barrel 100, ultrasonic cleaning is carried out using of a suitable system comprising a generator (not shown) and a transducer 230.

[0064] Preferably, the ultrasonic waves generated are of high power. These waves propagate in the water filling the barrel and create microscopic bubbles, the diameters of which are of the order of a micrometer. These bubbles are then excited by the same progressive US ultrasonic waves and burst, generating turbulence which makes it possible to decompose by mechanical action the undesirable bodies located nearby.

[0065] This cavitation phenomenon makes it possible, for example, to break tartar crystals, to burst the cell walls of micro-organisms and to remove residual traces of wine contained in the depths of the pores of the wood.

[0066] The higher the power of the ultrasonic waves, the more effective the mechanical cleaning action.

[0067] Thus, the ultrasonic cleaning step 550 provides a descaling, disinfection and sanitization action on the internal faces of the barrel.

[0068] Alternatively, heating can be carried out after cleaning, especially to regenerate the organoleptic potential provided by the barrel and therefore to preserve the quality of the wine which will be aged in the reconditioned barrel.

[0069] Nevertheless, the effect of ultrasonic cleaning on the organoleptic potential remains negligible and does not justify reversing the heating and ultrasonic cleaning steps, especially since this reversal requires additional disassembly and reassembly of the bases.

[0070] Indeed, the order of the steps shown in [Fig.2] corresponds to an optimal solution obtained by the inventors after different tests in which different orders were tested. Other combinations remain possible, however, and are covered by the present invention, the main object of which is the combination of planing and ultrasonic cleaning.

[0071] Finally, step 560 of vaporizing tannins is not obligatory and its implementation depends on health considerations. Indeed, this step is recommended when the reconditioned barrel is intended to be transported for long periods, in particular when it is intended for export.

[0072] [Fig.7] shows schematically the step 560 of vaporization of tannins which consists of spraying unheated liquid tannins T onto the internal walls of the barrel 100 by means of a suitable device such as an atomizer (spray).

[0073] Of course, the taste tests can be carried out only on a sample of reconditioned barrels to decide whether or not to carry out step 560 of vaporizing tannins on the other barrels.

[0074] It is readily apparent from the present description that certain steps of the re method packaging may be slightly modified and / or reversed without departing from the scope of the invention.

Claims

Claims

1. Method (500) for reconditioning a used barrel (100) comprising staves (10) and two bottoms (30), the assembled staves forming a shell (50), said method comprising: a step (510) of dismantling the bottoms to isolate the shell (50); a step (521) of planing the internal faces (11) of the shell to remove a layer penetrated by substances previously stored in the barrel; and characterized in that it comprises, after steps (510) and (521): a step (540) of heating the shell; and a step (550) of cleaning the internal faces of the barrel by ultrasound, and in that the internal faces of the bottoms (30) are also planed.

2. Method according to claim 1, further comprising a step (530) of reassembling the bottoms (30) just before the step (550) of ultrasonic cleaning.

3. Method according to claim 2, in which the step (550) of ultrasonic cleaning is carried out in the reassembled barrel (100), through a bung hole (15) of said barrel.

4. Method according to any one of the preceding claims, in which the planing step (521) is automated and consists of rotating the shell (50) around its axis of revolution and coming into contact with the internal faces of said shell with a planing head (213) movable along at least two axes.

5. A method according to any preceding claim, wherein the ultrasonic cleaning step (550) is performed with high power ultrasound of a frequency of 20kHz.

6. Method according to any one of the preceding claims, further comprising a final step (560) of vaporizing tannins on the internal faces of the barrel (100) until the desired organoleptic properties are obtained.

7. A method according to any preceding claim, wherein the heating step (540) and the ultrasonic cleaning step (550) are performed in that order.

8. Reconditioned barrel, obtained by a reconditioning method (500) according to one of the preceding claims.

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