PROCESS FOR WINE-MAKING FROM CLARIFIED JUICE

Abstract

A winemaking method comprising in the following order: A step of harvesting the grapes; A step of stripping; A step of pressing; A step of separating the must and the pomace; A step of setting aside the pomace under inert atmosphere in a first container; A step of clarifying the must into a second container; A step of recombining the pomace and the clarified must in a single container; A step of fermenting.

Claims

1. A winemaking method characterized in that it comprises in the following order: E1—A step of harvesting the grapes; E2—A step of stripping; E3—A step of pressing; E4—A step of separating the must and the pomace; E5—A step of setting aside the pomace under inert atmosphere in a first container; E6—A step of clarifying the must into a second container; E7—A step of recombining the pomace and the clarified must in a single container; E8—A step of fermenting.

2. The method according to claim 1 comprising a step of sulfiting and sowing of clarification enzymes during steps E1 and/or E2.

3. The method according to claim 1 wherein the first and second containers are tanks.

4. The method according to claim 1 wherein the container for step E7 can be the first or second tank (C1, C2) or a third tank different from the first two.

5. The method according to claim 3 wherein in step E5 the pomace is inerted in a first tank and wherein step E7 is done by adding the must into the first tank.

6. The method according to claim 3 wherein the tanks are each provided with a tight closing cover.

7. The method according to claim 1 wherein the pomace and the must are respectively put in the first and second tanks (C1, C2) directly after separation thereof and the air in the tanks is replaced by an inert gas.

8. The method according to claim 1 wherein the step of setting aside the pomace is done under an atmosphere inerted using a mixture of 80% argon and 20% carbon dioxide.

9. The method according to claim 1 wherein the steps E3 to E6 are done at a temperature included between 0 and 10° C.

10. The method according to claim 1 comprising a step of assembling various grape varieties between step E7 and E8.

11. The method according to claim 1 further comprising an additional step E9 of maturing on the lees.

Description

[0037] Other aspects, goals and advantages of the invention will appear upon reading the following description of an embodiment of the invention, given as a nonlimiting example. The invention will also be better understood in light of the attached drawings in which:

[0038] FIG. 1 shows the first part of a method according to the invention (steps E1 to E5).

[0039] FIG. 2 shows the second part of a method according to the invention (steps E6 and E7).

[0040] FIG. 3 shows the various steps of a method according to the present invention.

[0041] In the following, a specific embodiment of the present invention is described in detail.

[0042] The winemaking method from the present example comprises several successive steps.

[0043] First, a step of harvesting the grapes E1. This step is followed by a step of sulfiting and sowing of clarification enzymes. The grape, yeast or microbial flora are not naturally completely without these enzymes. Supplying exogenous enzymes is in general justified by the weak activity levels naturally encountered in grapes or yeasts. The natural winemaking phenomena can be accelerated and optimized with this addition.

[0044] It is next necessary to detach the grape berries from the stalks. The stripping E2 or destemming, consists, during or right after the harvest, of removing the stalks or peduncles from the bunch of grapes for retaining only the grape berries. In fact the presence of stalks could contribute herbaceous, vegetable, astringent and bitter tastes to the wine.

[0045] The stripping is done mechanically by using a stalk separator. It is done at a slow rate in order to avoid crushing the bunches of grapes or breaking the stalks which could release sap with the berries. A more selective sorting can then be considered in order to eliminate the remainder of the foreign matter, such as vegetable debris. Traditionally the sorting is done by means of a sorting table.

[0046] Next, a pressing step E3 occurs which allows the separation of the must and the pomace. The berries are crushed and the juice that they contain is separated from the solid parts (skin and seeds). In the example shown, a continuous pressing device is used composed of an upper conveyor belt and a lower rolling perforated belt, the working space which separates them decreases on moving in the forward direction, which causes the intended pressing and the passage of the juice through openings in the perforated belt.

[0047] At the end of this pressing step, the pomace (solid part) and the must (liquid part) are separated E4. The pomace spills into a first-tank C1 whereas the must is routed to a second tank C2.

[0048] The two tanks have a capacity suited to receive the juice (must) and the pomace. They comprise a bottom in their lower part, extended by a circular wall and end in their upper part with a bottleneck provided with a tight cover. In the example shown, cylindrical tanks are illustrated having for example a diameter D1 included between 1 m and 4 m and a height H1 included between 2 m and 5 m.

[0049] These tanks may however have various shapes and be made in any other type serial typically used in winemaking methods such as for example: concrete tanks, barrels, hogsheads, vats, muids or half-muid.

[0050] The oxygen in them can then be replaced by a mixture of 80% argon and 20% carbon dioxide; this mixture is heavier than air. This handling is known as such in the winemaking field and therefore it is not described in detail here. Thus, the pomace is inerted and preserved from oxidation (step E5), just like the must. Other gases or mixtures of gases can be considered in order to deprive the tanks of oxygen and prevent the oxidation of their content. The inert gas, heavier than air, is going to fill the tank starting from the bottom whereas at the same time, the lighter air is displaced from the top of the tank. Advantageously, tanks equipped with a tight closing cover which can then be reclosed are used here. Advantageously, this cover will be provided with a safety valve.

[0051] In particular, the inert gas coming from other tanks in fermentation can be recovered by a bridging system.

[0052] Two tanks in hermetically closed position are shown in FIG. 2.

[0053] The step of clarifying the must E6 can then commence. The clarifying is done by floating, preferably while sending a pressurized gas (generally CO2) and a binder (ideally gelatin) in the must. This gas can be added by an opening with selective closure arranged in the lower part of the tank. The gas can also be sent through a tube inserted by the top of the tank and opening out in the bottom of the tank. This mixture carries along the must solids and takes them to the surface. The liquid can also be clarified by cold settling, possibly with the help of enzymes. In this case, after extraction of the juice, pectins, coming from the grape berries and negatively charged, form a protective layer around positively charged solid particles, which keeps them in suspension. The action of breaking down these pectins by a specific enzyme, pectinase, serves to expose positive charges on these complexes which flocculate with the pectins to form larger size particles. When these particles reach a certain size, they settle and can be eliminated by racking.

[0054] Clarifying the liquid by filtration can also be considered. The step of recombining E7 the pomace and the clarified must in the first tank C1 occurs.

[0055] It is simpler to limit the handling of the pomace because it is fragile and breaks down very quickly. The clarified juice, also called clear juice, is gathered from the second tank C2 by racking in order to be returned to contact with the pomace. Alternatively, the pomace can be added into the second tank C2 or the juice and the pomace can both be gathered in a third tank.

[0056] It is preferably at this step that the assembly of the various grape varieties can be done.

[0057] Finally, a fermentation step E8 finishes off the winemaking method. Fermentation is the natural chemical process during which sugar from the great is transformed into alcohol under the action of the yeasts. Compounds that are higher alcohols, fatty acid esters, or even aldehydes are synthesized by the yeast in parallel to the transformation of the sugars into alcohol. Good progress of the winemaking involves an optimal development of the yeasts.

[0058] The fermentation can optionally be considered with a malolactic fermentation which corresponds to the transformation of malic acid into lactic acid via anaerobic bacteria called lactic bacteria. This step leads to a reduction in the acidity. It also allows a stabilization but even a softening of the wine. It can be done early, meaning at the same time as the alcoholic fermentation, or late in the months which follow, meaning during the maturing. It can be done in tank, or in a vat or keg.

[0059] The lees are composed of yeasts coming from the alcoholic fermentation and sometimes also bacteria if the wine undergoes malolactic fermentation. The maturing of the wine on fine lees can then be considered, preferably, before the malolactic fermentation because the yeast lees are finer than the bacterial lees. This is a practice which improves the quality and stability of the wine.

[0060] These microorganisms experience a breakdown by autolysis. This autolysis can be enhanced and accelerated by addition of enzymes such as beta-glucosidases. By breaking down, the lees release aromatic compounds and also molecules which improve the mouthfeel such as polysaccharides. Wines after maturing on lees have a more intense bouquet and also a more unctuous flavor.

[0061] Also, the natural stabilization at the chemical level is accentuated. The appearance of tartrate crystals (potassium bitartrate) in the bottom of the bottle also becomes rarer. The stability of the wines against tartrate precipitation is increased because of this maturing on the lees.

[0062] This maturing on fine lees is not, at present, possible in red wine except by using the present invention.

[0063] The steps E1 to E6 are particularly sensitive and will preferably be done at a temperature included between 0 and 10° C. As previously seen, this low temperature in particular provides protection from oxidation and blocks any unwanted spontaneous start of fermentation at this stage.

[0064] A thermovinification method can also be advantageously inserted at step E7 by heating the clarified juice at the time of the reincorporation of the juice in the pomace in the case of liquid phase thermovinification.

[0065] This technique consists of heating the grape varieties to 60-80° C. for a fairly short time of 6 to 18 hours and then quickly cooling to around 20° C. Thermovinification applied to this method gives even finer and fruitier wines than in a conventional method.