Method for reconditioning barrels by ultrasonic sound and barrels produced by such a method

Description

Technical field

[0001] The present invention relates to a method for reconditioning a used barrel according to the preamble of claim 1. Such a method and the corresponding barrel are known from document US 2006 / 191424 A1. State of the art

[0002] Barrels have been known since ancient times, thanks to the hot bending of wood. This very practical container was used and continues to be used today for the preservation or aging as well as the transport of various food products, especially liquids, including wine.

[0003] Despite significant advances in food technology, and more specifically in winemaking, replacing the traditional wooden barrel seems difficult to imagine. Indeed, beyond 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.

[0004] To be reused in good conditions, barrels must be reconditioned after a certain number of uses. Indeed, in the case of wine aging, the aromatic contribution of the barrels diminishes with consecutive vinifications.

[0005] There are many reconditioning processes to make used barrels reusable. Most of these processes involve water jet cleaning followed by chemical treatments that can sometimes cause additives to dissolve in the wine, potentially affecting its quality.

[0006] Other processes use steaming by injecting pressurized steam. The steam condenses on the inner 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.

[0007] 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.

[0008] Most often, the different techniques mentioned above are combined to obtain a reconditioning process adapted to the specificities of each type of barrel.

[0009] WO2008054707 describes, for example, methods for reconditioning a barrel previously used to store a given substance, comprising the steps of determining barrel material-specific cutting parameters to controllably cut the barrel material; removing a desired depth of 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 removing and testing steps if the presence of the substance is detected in or on the barrel.

[0010] The use of ultrasound is also known for cleaning barrels. However, ultrasound alone is not very effective for descaling and requires extensive prior cleaning by mechanical action.

[0011] Document FR2975312 describes a process for cleaning, descaling and disinfecting barrels, comprising drilling the bottom of the barrel, cleaning the inside with a high-pressure hot water jet, finishing the cleaning with ultrasound and type C germicidal ultraviolet rays, rinsing followed by draining, and wicking with sulfur dioxide (SO 2 ). This solution corresponds to a very thorough physical and chemical cleaning of the walls, but does not guarantee deep cleaning when the walls are well penetrated by the wine, as it does not offer any removal of material from said walls. Presentation of the invention

[0012] 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, economical and particularly eco-responsible.

[0013] 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 hull; and a step of planing the internal faces of the hull to remove a layer penetrated by substances previously stored in the barrel.

[0014] This process is remarkable in that it includes, after the aforementioned steps: a step of heating the hull; and a step of cleaning the internal faces of the barrel by ultrasound.

[0015] The reconditioning process according to the invention thus makes it possible to increase the lifespan of the treated barrels while preserving their organoleptic potential.

[0016] Advantageously, the internal faces of the barrel bottoms can also be planed.

[0017] According to one embodiment, the method further comprises a step of reassembling the bottoms just before the ultrasonic cleaning step.

[0018] More particularly, the ultrasonic cleaning step can be carried out in the reassembled barrel, through a bung hole in said barrel.

[0019] 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.

[0020] Advantageously, the ultrasonic cleaning step is carried out with high-power ultrasound with a frequency of 20 kHz, for example. According to the invention, the method further comprises a final step of vaporizing tannins on the internal faces of the barrel, for sanitary reasons, especially when the reconditioned barrel is intended to be transported for long periods before being filled. Advantageously, the heating step and the ultrasonic cleaning step are carried out in this order to avoid additional disassembly and reassembly.

[0021] 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

[0022] The figures are provided for purely illustrative purposes to provide 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.

[0023] It is thus illustrated in: •[ Fig. 1 ]: a perspective view of a barrel for implementing the invention; • [ Fig. 2]: a synopsis of the main steps of a barrel reconditioning process using ultrasound according to one embodiment of the invention; • [ Fig. 3 ]: the stage of dismantling the funds; • [ Fig. 4 ]: the automatic hull planing step; • [ Fig. 5 ]: the barrel heating stage; • [ Fig. 6 ]: the stage of cleaning the barrel by ultrasound; • [ Fig. 7 ]: the tannin vaporization stage. Detailed description of embodiments

[0024] In the embodiment described below, reference is made to a method for reconditioning barrels using ultrasound, intended primarily 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.

[0025] In this description, the term "barrel" designates a wooden container with symmetry of revolution, swollen in the 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.

[0026] There figure 1 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 made in its main stave.

[0027] Barrel 100, when emptied of its contents (wine for example), must be cleaned to prevent 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 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.

[0028] For this purpose, the barrel 100 can be reconditioned by implementing an ultrasonic reconditioning method according to the invention.

[0029] There figure 2 represents the main steps of a process for reconditioning 500 a barrel, said process 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 a step 560 of vaporizing tannins inside the barrel.

[0030] Of course, the 500 reconditioning process is carried out after rinsing, draining and drying the barrel, to prepare for the woodworking stages, namely planing and sanding.

[0031] 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.

[0032] There figure 3 schematizes step 510 of dismantling the bottoms 30 to isolate the hull 50.

[0033] Next, step 521 of planing the inner faces of the hull consists of planing the inner face of each stave in order to remove a layer penetrated by the wine. This allows the ethanol present in the wood to be removed before ultrasonic cleaning.

[0034] Planing can be done manually or automatically using any suitable tool or system.

[0035] There figure 4represents 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.

[0036] The planing is then done in successive circumferential strips along the entire length of the hull 50.

[0037] Of course, planing the inner faces of the staves can be done differently, for example by dismantling the staves and planing them individually using a traditional plane.

[0038] 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.

[0039] However, not planing the bottoms 30 is preferred to preserve a tartaric film and avoid the wine coming into contact with virgin wood.

[0040] 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 finish of the reconditioned barrel. This step can be carried out at any time during the process.

[0041] 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 staves or in the lower bottom of said barrel.

[0042] Planing step 521 thus constitutes an initial cleaning (stripping) of the barrel by removing material, which allows the removal of residual deposits but also the layers of wood penetrated by the ethanol.

[0043] However, mold may remain deep in the pores of planed wood.

[0044] The following steps therefore allow you to thoroughly disinfect the barrel.

[0045] Before reassembling the barrel for ultrasonic cleaning, it is best to heat the hull to avoid having to disassemble and reassemble the bottoms again. Therefore, it is best to perform steps 530 (heating), 540 (reassembling the bottoms), and 550 (ultrasonic cleaning) in that order.

[0046] There Figure 5 schematizes the step 530 of heating the hull 50 which allows the internal faces of the staves to be “leathered” using a flame or ember 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.

[0047] Step 540 of reassembling the bottoms consists of replacing the bottoms 30 on the heated shell 50 to allow the cleaning of the reconstituted barrel by ultrasound.

[0048] There figure 6 schematizes step 550 of ultrasonic cleaning which consists firstly of completely filling the barrel 100 with hot water and, secondly, of generating ultrasonic waves in the water to create a cavitation phenomenon.

[0049] According to the illustrated embodiment, the barrel 100 is filled by a suitable filling means 220, such as a lance or a pipe connected to a hot water tank, introduced into the bung hole.

[0050] The filling water can, for example, be at a temperature of around 60°C and under pressure to encourage its penetration into the pores of the wood.

[0051] Hot filling water can have a preliminary cleaning effect, especially on fatty substances that emulsify and disintegrate more easily under the effect of heat.

[0052] After filling the barrel 100, ultrasonic cleaning is carried out using a suitable system comprising a generator (not shown) and a transducer 230.

[0053] Preferably, the ultrasonic waves generated are of high power. These waves propagate in the water filling the barrel and create microscopic bubbles, whose diameters 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 unwanted bodies in the vicinity.

[0054] This cavitation phenomenon can, for example, break up tartar crystals, burst the cell walls of microorganisms, and remove residual traces of wine contained deep within the pores of the wood. The higher the power of the ultrasonic waves, the more effective the mechanical cleaning action.

[0055] Thus, step 550 of ultrasonic cleaning provides a descaling, disinfection and sanitization action on the internal faces of the barrel.

[0056] Alternatively, heating can be carried out after cleaning, mainly to regenerate the organoleptic potential provided by the barrel and therefore preserve the quality of the wine which will be aged in the reconditioned barrel.

[0057] However, 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.

[0058] In fact, the order of the steps represented in figure 2 corresponds to an optimal solution obtained by the inventors after various tests in which different orders were tested. Other combinations remain possible and covered by the present invention, the main object of which is the combination of planing and ultrasonic cleaning.

[0059] There figure 7 schematizes step 560 of vaporization of tannins, according to the invention 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).

[0060] Of course, taste tests can only be carried out on a sample of reconditioned barrels to decide whether or not to carry out step 560 of vaporization of tannins on the other barrels.

Claims

1. A method (500) for reconditioning a used cask (100) comprising staves (10) and two heads (30), the assembled staves forming a shell (50), said method comprising: a step (510) of disassembling the heads to isolate the shell (50); a step (521) of planing the inner faces (11) of the shell to remove a layer penetrated by substances previously preserved in the cask; and such that it comprises, after the steps (510) of disassembling the heads and (521) of planing the inner faces: a step (540) of heating the shell; and a step (550) of ultrasonically cleaning the inner faces of the cask, in that the inner faces of the heads (30) are also planed, characterized in that said method further comprises a final step (560) of vaporizing tannins on the inner faces of the cask (100) until the desired organoleptic properties are achieved.

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

3. The method according to claim 2, wherein the ultrasonic cleaning step (550) is carried out in the cask (100) reassembled, by a bung hole (15) of said cask.

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

5. The method according to any one of the preceding claims, wherein the ultrasonic cleaning step (550) is performed with high-power ultrasound having a frequency of 20kHz.

6. The method according to any one of the preceding claims, wherein the heating step (540) and the ultrasonic cleaning step (550) are performed in this order.

7. A reconditioned cask, obtained by a reconditioning method (500) according to one of the preceding claims.