HRP20010207A2 - Device and method for cold thickening of must - Google Patents

Description

The field to which the invention relates

This invention relates to winemaking and cellaring, and therefore can be classified according to the International Classification of Patents in "Preparation of must from grapes" under C 12 G 11/02.

Technical problem

In previous practice, when due to weather problems for winegrowers there is not enough malt in the squeezed grape must, which is why it is necessary to sweeten the must additionally, or when one wants to prepare dessert wines, the problem was solved by adding a malting agent - sucrose, which is allowed by our existing law. However, in the European Community, to which we want to export our wine products, this will not be acceptable! The reason for this is their regulations, according to which the addition of sucrose to quality wines is already not allowed. However, in order to improve the malt content, it is only allowed to increase the malt by adding concentrated must, which should be produced exclusively from the same must from which the wine is planned to be produced. It is also possible to make predicate wines similar to, for example, wines from the so-called "ice harvest" or "ice wines" for short.

The technical problem that needs to be solved is a new device and procedure for cold condensation of must without adding sucrose.

State of the art

The technique of thickening the must by boiling it at atmospheric pressure and a temperature of 100°C is well known. The disadvantage of this process is the change in the organoleptic characteristics of the wines produced in this way, such as the smell of caramel and the like. Another method that is used is cooking under reduced pressure, where the steam is vacuumed by vacuum pumps, but I am not aware that this is also applied in the Republic of Croatia.

Presentation of the essence of the invention

The essence of the invention is the continuous thickening of must at low temperatures. On this equipment, it is possible to thicken the must, if desired, even at temperatures below 15°C. The optimal operating mode is in the range from 20°C to 50°C. With an already made and tested device, which occupies a volume of less than 100 dm3 (0.1 m3) and a rated electric motor drive power of less than 3 kw, it is possible to extract 250 liters of water from the treated must in 24 hours, without human supervision. With the concentrated must thus obtained, the base malt content can be improved by 2% (eg from 17% to 19%) for 2100 liters of the same must. A significant additional characteristic of the device as a whole is also its relatively low price considering the possibility of installing serially produced machines and fittings that are built into the device.

Brief description of the drawing

Figure 1. Schematic view of the device

Figure 2. Vacuum column (axial section)

Figure 3. The bottom of the vacuum column (cross section)

Figure 1 shows how fresh must (1) will be sucked into the vacuum column (5) through the suction pipe (2), filter (3) and level regulator (4). At the bottom of the column there is an outlet pipe through which the must is poured into the circulation pump (13), and then it is pushed towards the distribution armature with an overflow valve (14), where the main flow of the flow goes over the must heater (15) and the tangentially placed nozzle jet (16). into the vacuum column (5), while a smaller part (approx. 5%) is separated via the overflow valve (14), depending on the density of the must, into the container (17). At the top of the column (5), the air and water vapor are removed via the water precooler (7), the water vapor condenser (8) and the small condensate collector (9) in the vacuum pump (11), and then it is removed through the discharge tube (12). . The compressor (18) presses the cooling medium into the exchanger (15) where it transfers the heat of condensation to the must, then it expands through the muffler (19) in the steam condenser (8), where it takes away the heat from the condensed steam, from where it is sucked in by the compressor (18). Both thermal circuits can work continuously, that is, the pump (13) and the compressor (18) work continuously if necessary. The vacuum pump (11) is switched on periodically, depending on the collected condensate (19) and the increase in pressure in the vacuum system.

Figures 2 and 3 show a vacuum column (5) that sucks in circulating must through a nozzle (16), which at high speed through a directed narrow and flat slot (25) with a tangential flow slightly downwards covers the inner cylindrical wall of the column so that the must in a thin layer moves spirally towards the bottom of the column, releasing water vapor and partially retaining its kinetic energy, which it partially converts at the bottom via the spiral ribs (21) into potential energy to more easily flow towards the circulation pump (13) and to reduce cavitation on the pump rotor . The level regulator (4) shakes the fresh must (1) into the pot (20) and doses it through the side openings (26) into the circulation system. The top of the column (22) is detachable and sealing is done via the circular ring (24). In the dome of the top of the column (22) there are labyrinth rings (23) to prevent the exit of circulating must drops.

Detailed description of one way of realizing the invention

The must thickening procedure according to the invention is carried out in the following order:

a) immediately after harvesting and pressing the grapes, a selected amount (e.g. 5%) of the same fresh must (1) should be strained into a special container, so that there are no mechanical impurities in it, and then the suction pipe (2) should be immersed in the same container;

b) turn on the vacuum pump drive (11) so that the created negative pressure starts sucking fresh must through the suction pipe (2) into the vacuum column (5) via the filter (3);

c) turn on the cooling medium compressor drive (18) to heat up the thermal circular flow of the cooling medium and wait until the temperature of the cooling medium on the return to the compressor rises above 0°C. This can be seen from the outer surface of the return pipe, where frost is caught immediately after the start, and when it melts, we know that the temperature has been reached above 0°C;

d) turn on the drive of the circulation pump (13) for must circulation;

e) the discharge pipe from the overflow valve (14) should be immersed in the container for condensed must (17). When the vacuum pump (11) sucks the must into the column (5), and then the air up to the negative pressure that is selected according to the desired water evaporation temperature (this is determined by selecting the necessary negative pressure, e.g. 80 millibars), the vacuum pump is automatically turned off, and the non-return valve (10) closes the air return back to the vacuum system;

f) when part of the condensate collects in the manifold and reduces the pressure (increases the negative pressure), the vacuum pump (11) is automatically switched on again via the pressure switch (as on a domestic hydrophore);

g) after a certain time of operation of the compressor (18), when the cooling medium reaches the desired temperature depending on the evaporation temperature, the electromagnetic valve for dosing the cooling water for precooling the water vapor is automatically opened to balance the excess heat generated by the compressor power, i.e. to keep both stable thermal cycle process:

1. the process includes heating the must for boiling with vacuuming at low temperatures,

2. the process includes compression and expansion of the cooling medium;

h) after a certain time, when the must thickens, i.e. when its specific density increases, i.e. when its graininess (viscosity) decreases, the resistance to circulation, i.e. the pressure in the pressure pipeline, increases, which is why the overflow valve (14) opens and part the circular flow of the already condensed must goes out into the container (17).

With this process, a continuous concentration of must was achieved, which can last as long as there is must, electricity and water. In the event of interruption of operation for any reason, the concentrated must produced by this process can, after restarting, reach the original required quality as soon as the same adjusted parameters of temperature and pressure are reached in both circular processes.

Method of application of the invention

For the production of the device according to this invention, it is necessary and sufficient to have the average knowledge and skill of an expert in mechanical engineering, and for its use it is sufficient to follow the instruction manual.

The device does not have any harmful effects on the environment during production and use, because it does not pollute the environment with harmful waste substances, nor are harmful substances introduced into it. Therefore, this device can be considered environmentally friendly.

The device is intended to be portable when it has a total weight of approximately only 100 kg. Such a portable device should be sufficient for the processing of grape must in the amount of 1 wagon/day (equivalent to approximately 6000 l/day). For the purposes of processing larger quantities of must, it is necessary and possible to construct a device of a stable type with larger dimensions on the basis of essentially the same technical solution according to the invention, and therefore, if necessary, determine assemblies and fittings of a larger capacity.

An important characteristic of the method of application of this device according to the presented invention is its continuous operation.

This device can be applied not only to grape must but also to other similar products: the invention enables the condensation of various other fruit juices in the cold without the use of preservatives, but also other liquid drinks such as milk and the like.

The device is designed in such a way that its serial production is possible at a relatively low price for the case of a portable version, so that such a device would be available to most of our winegrowers and cellarmen.

Claims (4)

1. The device for cold condensation of must in order to increase the content of malt in the must without adding sucrose, is indicated by the fact that it consists of: must container (1), suction pipe (2), filter (3), level regulator (4), vacuum column (5), steam line (6), water precooler (7), water vapor condenser (8), condensate container (9), non-return valve (10), vacuum pump (11), condensate outlet pipe (12), circulation pump (13), overflow valve (14), container for condensed must (17), must heater (15), injector (16), cooling medium compressor (18), expander (19) and fittings and pipelines for interconnection. 2. The device according to claim 1, characterized in that the vacuum column consists of a cylindrical container (5), the top of the column (22), labyrinth plates (23), a circular ring (24), a nozzle (16) with a narrow slit (25) ), level regulator (4), pot for fresh must (20), side openings on the pot (26) and spiral ribs (21) for directing the flow of concentrated must towards the lower outlet of the column. 3. The procedure for cold condensation of must in the device according to requirements 1 and 2, is indicated by the fact that the cleaned must is poured from the container (1) through the suction pipe (2) through the mechanical filter (3) and the level regulator (4) into the vacuum chamber ( 5) from where the circulation pump (13) pushes it through the overflow valve (14) with a smaller part into the container for condensed must (17) and the larger part into the must heater (15), and through the nozzle (16) it returns to the vacuum column ( 5), while the water vapor released from the warm must under low pressure goes between the labyrinth plates (23) through the top of the column (22) into the water precooler (7) and the condenser (8), where it condenses into water, and the water and remaining traces of steam they go over the condensate container (9) through the non-return valve (10) using the vacuum pump (11) into the condensate outlet (12). 4. The device and procedure for cold thickening of must according to requirements 1-3, it is indicated that it can be used except for thickening grape must and for thickening all other fruit juices and milk drinks, as well as other liquid food products.