Method for preparing frothed milk or café crème

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Office for Industrial Property The Netherlands © 1007167 © C OCTROOI²⁰ © Patent application: 1007167 © Int.CI.⁶

A47J31 / 44 © Submitted: 30.09.97

<td>© Registered:</td><td>© Patent holder (s):</td>

<td> 31.03.99</td><td>Sara Lee / DE NV in Utrecht.</td>

<td>© Date:</td><td>© Inventor (s):</td>

<td> 31.03.99</td><td>Adrianus Petrus Matthijs van Straten in Linschoten</td>

<td>© Published:</td><td>Willem Nanko Mels in Utrecht</td>

<td>01.06.99 IE 99/06</td><td>Jan Anne Mouse in Odijk © Authorized representative: Mr. Drs. SU Ottevangers cs in 2508 DH The Hague.</td>

§4) Process for preparing frothed milk or café crème.

© According to the method of preparing frothed milk or café crème, milk concentrate or coffee concentrate is mixed with water using a venturi chamber. The venturi chamber includes a water inlet, a concentrate inlet and an outlet. Furthermore, use is made of a vortex chamber located downstream of the venturi chamber which is in fluid communication with the outlet. The water is supplied under pressure via the water inlet to the venturi chamber, so that a negative pressure is created in the venturi chamber. The concentrate inlet is brought into fluid communication with a supply of milk or coffee concentrate so that, as a result of the underpressure in the venturi chamber, suction is made via the concentrate inlet, milk or coffee concentrate in the venturi chamber. The milk or coffee concentrate and the water then flow together, through the outlet, into the whirl chamber, beating the milk or coffee concentrate in the whirl chamber into frothed milk or café crème.

NL C1007167

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The contents of this patent correspond to the original filed description with claim (s) and any drawings.

VO 1111

Title: Method for preparing frothed milk or café crème.

The invention relates to a method for preparing foamed milk or café crème, respectively.

The frothed milk is often used to prepare cappuccino and similar drinks. The frothed milk contains many small air bubbles.

Cafe-cream is understood to mean black coffee with a fine-bubble, slightly light brown colored foam layer when it is in a container such as a cup.

It is known to prepare frothed milk by mixing milk with steam. For example, mixing of the milk and steam can be done by hand. The milk is placed in a container. Steam is then blown into the milk using a steam pipe. When the container is moved up and down by hand relative to the steam pipe, the steam and air are beaten in the milk. Frothed milk will form after some time.

Furthermore, it is known, for example, from European patent application 0 243 326 to prepare frothed milk by means of an emulsifier. With the aid of the emulsifying device, steam, air and milk are mixed together in such a way that frothed milk is obtained. To this end, the emulsifier is provided with a first steam inlet, an air inlet, a first milk inlet, a suction chamber and a swirl chamber. The first steam inlet, the air inlet and the first milk inlet open into the first suction chamber. Furthermore, the first suction chamber is in fluid communication with the whirl chamber. The milk is contained in a storage vessel which is in fluid communication with the milk inlet via a conduit. In use, steam is supplied to the suction chamber via the steam inlet. The result is that milk is sucked from the container to the suction chamber via the milk inlet. Air is also drawn in via the air inlet. The mixture of steam, air and milk flows at such a speed to the whirl chamber that frothed milk is created in the whirl chamber as a result of swirls. The frothed milk can then leave the device via an opening in the whirl chamber. In order to prevent spoilage of the milk, it is also known to cool the container in which the milk is located. The container of this milk often consists of a small refrigerator in which a carton of milk with a content of, for example, 1 liter is stored.

A drawback of the first described method for preparing frothed milk is that it is quite laborious and takes a relatively long time. In the catering industry, in particular, the time required to prepare the frothed milk is unacceptable.

A drawback of the second described method for preparing frothed milk, in which use is made of the emulsifying device, is that when used in the catering industry the milk carton is often empty quickly. The carton will then have to be replaced by another carton of milk, which again takes an undesirable amount of time.

The object of the invention is to provide a method for preparing foamed milk that offers a solution to each of the above-mentioned drawbacks.

It is known per se to produce café crème by spraying coffee at a high speed into a chamber surrounded by walls, which chamber is provided with an outlet opening at its bottom. The chamber with outlet opening is often designed as a piston, which can also comprise a filter holder filled with ground coffee. A drawback of the known system is that a cafe cream is dispensed with an inhomogeneous foam layer. Another object of the invention is to provide a solution to the latter drawback.

According to the invention, the method for preparing a foamed milk or café crème, respectively, is characterized in that milk concentrate or coffee concentrate, respectively, is mixed with water using a venturi chamber which has at least one water inlet, includes a concentrate inlet and an outlet and a vortex chamber located downstream of the venturi chamber which is in fluid communication with the πθΊ 67 outlet with the pressurized water being supplied to the venturi chamber through the water inlet to create a negative pressure in the venturi chamber, the concentrate inlet is brought into fluid communication with a supply of milk or coffee concentrate, respectively, so that, as a result of the underpressure in the venturi chamber, suction is made via the concentrate inlet, respectively milk or coffee concentrate, into the venturi chamber, respectively, the milk or coffee concentrate and the water flow together via the outlet to the whirl chamber, whereby the milk or coffee concentrate and the water are beaten in the whirl chamber, respectively, into foamed milk or café crème.

Surprisingly, it has been found possible to prepare frothed milk of very high quality using a venturi chamber in fluid communication with a downstream swirl chamber. The preparation of an amount of frothed milk takes relatively little time. Moreover, because a stock of concentrated milk is used as the starting product, this means that it takes a relatively long time before this entire stock is consumed. Especially when used in the catering industry, this has the advantage that a carton of concentrated milk will be empty much less quickly than a carton of regular milk.

It is noted that, as stated in European patent application 0 243 326, it is also known to use a venturi chamber for preparing frothed milk. However, the starting products here are milk and steam instead of concentrated milk and water.

Furthermore, it surprisingly appears that according to the invention a perfect café crème can be prepared with the aid of a venturi chamber and a swirl chamber from concentrated coffee and water. It turns out that the café crème has a very homogeneous fine-bubble foam layer.

Preferably, air is also drawn in through the venturi chamber. This further enhances the fine-bubble character of the beverage to be prepared for consumption. With others

1007¹67 words, more foam of a homogeneous quality is formed.

In particular, respectively, the stock of milk or coffee concentrate is cooled, with the result that a very large amount of foamed milk or café crème can be prepared, respectively, without the amount of milk or coffee concentrate having to be replaced.

In particular, heated water is supplied to the first inlet to obtain heated or hot frothed milk or hot café crème.

Furthermore, in particular, the ratio between the amount of milk or coffee concentrate and the water supplied to the venturi chamber, and the temperature of the milk or coffee concentrate and the water, are coordinated such that the frothed milk or the café crème, respectively, which fluid chamber is hot. The stock of milk or coffee extract is then preferably cooled, so that the temperature of the milk or coffee extract which is supplied to the venturi chamber is relatively low. For example, a temperature lower than 10 ° C can be considered. It is also possible that the ratio between the amount of milk or coffee concentrate and the water supplied to the venturi chamber, respectively, as well as the temperature of the milk or coffee concentrate and the water, respectively, are coordinated to predetermine the temperature of the frothed milk or café crème that leaves the whirl chamber.

It is known from European patent application 0 241 687 to mix concentrates with water using a venturi chamber. In particular, this concerns fruit concentrates. A mixing chamber is used for mixing the water and the fruit concentrate. However, there is no foaming of the finished product. Feeding concentrated milk or concentrated coffee and heated water to a swirl chamber using a venturi chamber to obtain

007167 frothed milk or café crème, respectively, is therefore not known from European patent application 0 241 687.

The invention will now be further elucidated with reference to the drawing. Herein shows:

Figure 1a is a top view of a device for performing a method according to the invention;

figure 1b shows a top view of the device according to figure 1a;

figure 2a is a perspective view of a partly disassembled emulsifying assembly of the device according to figure 1;

Figure 2b is a three-dimensional view of the emulsifying assembly of Figure 2a with a front wall removed;

figure 2c shows a front view of the emulsifying assembly according to figure 2b;

figure 2d shows a side view in the direction of the arrow P of figure 2c;

figure 2e shows a top view of the emulsifying assembly according to figure 2a;

figure 3a shows a side view of a possible embodiment of an emulsifying device of the emulsifying assembly according to figure 2a;

figure 3b shows a partly cut-away front view of the emulsifying device according to figure 3a;

Figure 3c is a cross-section of the emulsifier taken on the line 3c-3c in Figure 3b;

figure 3d shows a top view of the emulsifying device according to figure 3a;

figure 3e shows in perspective the emulsifier of figure figure 3f three-dimensional view of a partly disassembled emulsifier according to figure 3a;

figure 3g shows a first longitudinal section of the emulsifier 35 according to the line 3g-3g in figure 3d;

figure 3h shows a second longitudinal section of the emulsifier taken on the line 3h-3h in figure 3d;

'&gt;! (Figure 3i is a third longitudinal section of the emulsifier taken on the line 3i-3i in Figure 3d; and Figure 3j is a fourth longitudinal section of the emulsifying machine taken on the line 3j-3j in Figure 3d;

In Figure 1, reference numeral 1 denotes an apparatus for preparing frothed milk. This frothed milk can be used to prepare cappuccino and similar drinks. The device is provided with an emulsifying assembly 4 for optionally preparing heated frothed milk and heated non-frothed milk.

The emulsifying assembly 4 is provided with a device 12 suitable for mixing the water and concentrated milk according to the method according to the invention to obtain heated milk. In this example, the device 12 is additionally provided with an air inlet for adding air to the concentrated milk for obtaining heated frothed milk. In this example, the device 12 consists of an emulsifying device and will therefore also be referred to as an emulsifying device 12.

The emulsifying assembly 4 further comprises a cooling device 14 in which a container filled with concentrated milk can be received for dispensing cooled concentrated milk from the stock of concentrated milk present in the container. For example, the stock of concentrated milk has a temperature below 10 ° C. This cooled concentrated milk is supplied via a first or second concentrate supply line 15a, 15b to be discussed later to a first or second concentrate inlet of the emulsifier 12.

The emulsifying assembly further comprises a hot water generator 16 which delivers hot water to a selection means 20 via a water line 18. The selection means 20 optionally adjustably delivers the hot water supplied by the hot water generator 16 via the water line 18 to a first subsequent line. 22 or a second follow-up line 24.

The first concentrate supply line 15a is further provided with an aeration valve 26a while the second concentrate supply line 15b is provided with an aeration valve 26b. The aeration valves 26a and 26b in this example are placed on top of the cooling device 14. In this example, the cooling device 14 consists of a cooling unit 28, which is provided with a cooled chamber-enclosed space in which the said container with concentrated milk can be placed. This stock of concentrated milk is, for example, a carton of concentrated milk 30, as shown in hatched in Figure 1a. The concentrate supply lines 15a and 15b include a second open end 32a, 32b which is in fluid contact with the concentrated milk contained in the carton of concentrated milk 30. In this example, the two open ends 32a and 32b are almost at the bottom of the carton of concentrated milk.

Finally, the emulsifying assembly is further provided with a control unit 34 which generates control signals S and thereby controls the hot water generator 16, the selection means 20 and the aeration valves 26a and 26b.

In this example, the walls of the cooling unit 28 are mainly made of a metal. The emulsifying assembly is further provided with a cooling element 36 known per se with which the walls of the cooling unit 28 can be cooled. A further elaboration of the cooling device 14 will now be discussed with reference to Figure 2. The cooling unit 28 is provided with a bottom wall 38, upright side walls 40a, 40b, 40c and 40d and a top wall 42. The side wall 40d is detachably connected to the rest of the cooling unit 28 and can be removed, for example, in the space 44 surrounded by the chamber walls 40a, 40b, 40c, 40d, 38 and 42, a container filled with milk in the form of a pack of concentrated 30 milk.

As is clearly seen in Figures 2a, 2b and 2c, the first and second aeration valves 26a and 26b are mounted on the top wall 42 on the outside. From the first aeration valve 26a, a portion 46a of the concentrate supply line 15a extends in the space 44 vertically downwards. The portion 46a of the concentrate supply line is flexible so that it can be easily manipulated in a carton of concentrated milk. Furthermore, from the first aeration valve 26a, a second portion 48a of the concentrate supply line 15a extends into a hollow space of the top wall 42 and the upright side wall 40a. The upright side wall 40a is provided on its outside with an outlet opening 50 through which the second part 48a of the conduit 15a projects partly outwards. The portion of the conduit 15a protruding outwards terminates in a first open end 50a. The open end 50a is contained in a holder 52 attached to the upright side wall 40a.

Thus, the first concentrate supply line 15a includes a first open end extending in this example beyond the cooling unit 28 and a second open end located in the interior 44 of the cooling unit 28. Since the first part of the concentrate supply line 15a extends substantially within the space 44, while the second part 48a of the line 15a extends substantially through a hollow space in the chamber walls, the first concentrate supply line 15a extends substantially within the cooling unit extends.

The second concentrate supply line 15b is mounted in the cooling unit 28 together with the second aeration valve 26b in an entirely analogous manner, as discussed in relation to the concentrate supply line 15a.

The emulsifier 12 includes a first concentrate inlet 54a, a second concentrate inlet 54b, a first water inlet 56a and a second water inlet 56b. The emulsifying device 12 comprises a housing which is detachably connected to the cooling unit 28, in this case in particular detachably to the holder 52. In Figure 2a, the emulsifying device 12 is shown when it is detached from the cooling unit 28. In the remaining figures 2, the emulsifying device 12 is shown when it is connected to the holder 52 of the cooling unit 28. In the latter state, the first open end 50a of the concentrate supply line 15a is connected to the first concentrate inlet 54a. Also, the first open end 50b of the second concentrate supply line 15b is connected to the second concentrate inlet 54b. The first water inlet 56a and the second water inlet 56b are, in use, connected to the first follow-up line 22 and the second follow-up line 24, respectively. See also figure 1.

It is noted that the first and second concentrate inlet 54a, 54b of the emulsifying device 12 are located near the cooling unit 28, so that the concentrate supply line extends at least almost completely within the cooling unit (see also Figures 2b and 2c).

The first and second open ends 50a and 50b of the concentrate supply lines 15a and 15b are in this example in which a snap connection known per se is connected to the first and second concentrate inlet 54a and 54b, respectively. The emulsifier 12 can therefore be removed from the cooling unit for cleaning, for example, and can then be replaced.

Figure 2a shows the emulsifying assembly in a partially disassembled state. Here, the hollow space extending in the top wall 42 and the side wall 40a is designated by reference numeral 58. The top wall 42 is provided on the inside with an opening 60 through which the concentrate supply pipes 15a, 15b extend from the hollow space 58 in the wall 42 into the cooled space 44. In this example, the aeration valves 26a and 26b are assumed to be part of the concentrate supply lines 15a and 15b. The opening 60 in this example extends from the inside of the cooling unit to the outside of the cooling unit (see Figure 2a). These openings are closed again by the aeration valves when they are mounted (see figure 2b). Each aeration valve is provided with an inlet opening 62 and an outlet opening 64. The inlet openings 62 are respectively connected to the flexible parts 46a and 46b of the pipes

Π

15a and 15b. The outlet openings 64 are connected to the parts 48a and 48b of the conduits 15a and 15b.

Since the hollow space 48 is open for the purpose of mounting the pipes at the front of the cooling unit, the cooling unit is furthermore provided with a first insulating edge part 66 with which the said hollow space 58 can be closed. Because of the symmetry, the cooling unit is furthermore provided with a second insulating edge part 68 which, in mounted condition, forms a closed ring together with the first edge part. The concentrate supply lines 15a and 15b are detachably connected to the rest of the assembly. By removing the first edge part 66, the concentrate supply lines can be removed for cleaning or replacing, for example. The upright side wall 40d is provided with means known per se which it can detachably connect to the first and second edge parts 66 and 68 in order to close the cooling unit 28. The edge part 40d thus forms a kind of door which can be opened to place a milk carton in the space 28 and which can then be closed.

The cooling element 36 is also detachably connected to the cooling unit 28. At the bottom of the cooling element there is a fan that has the function to cool the cooling element.

The walls of the cooling unit 28 are mainly made of a metal. The cooling element is mounted on the wall 20b (see figure 2b-2e). The cooling element therefore directly cools the upright side wall 40b. Because all walls are made of metal and can therefore conduct heat well, all walls will be cooled by the cooling element 36. The hollow space 58 will also be cooled, with the result that the sub-pipes 48a and 48b are also cooled. The sub-pipes 46a, 46b are of course cooled because they are located in the space 44. In this example, the holder 52 is also made of metal, so that it is also cooled. This implies that both concentrate supply lines 15a and 15b are cooled in this example.

As shown in Figure 2, the second ends 32a and 32b of the concentrate supply lines 15a and 15b are at a height lower than the highest point of the respective concentrate supply lines. The highest point of the concentrate supply lines in this example is the aeration valves 26a and 26b. Since the second ends 32a and 32b are below the said highest points, the carton of concentrated milk 30 cannot drain by itself when the aeration valves are opened. In this example, both concentrate supply lines are substantially U-shaped and oriented such that each milk supply line extends in an upward direction from the first and second ends, respectively. In this example, the aeration valves 26a and 26b are located at the highest point of the concentrate supply lines 15a and 15b, respectively.

If milk is sucked in by means of emulsifying device 12 via the concentrate supply line 15a or via the concentrate supply line 15b, the supply line 15a, 15b will be completely filled with concentrated milk. When the suction is subsequently stopped, the liquid flow in the milk supply line 15a, 15b comes to a standstill and therefore liquid residues will remain in this line. The important objective of the aeration valve now is to prevent this. By opening the aeration valve 26a, 26b, the pipe 15a, 15b is aerated and residual liquid can flow back to the carton of concentrated milk 30 or flow to the emulsifier 12. It is noted that for this function of the aeration valve it is irrelevant where exactly is provided in the milk supply line 15a, 15b. In other words, the aeration valve can in principle be arranged for any function of the milk supply line 15a, 15b for the purpose of this function.

In some embodiments, however, it is also desirable to prevent siphoning. When, as described above, an attempt is made to stop the concentrated milk flow through a concentrate supply line 15a, 15b by terminating the suction of concentrated milk using the emulsifier 12, the concentrated milk flow may not be stopped even after the suction due to siphoning action will be ended. Siphon action may occur in particular when the first end 50a, 50b in vertical direction is lower than the height of the liquid level in the carton of concentrated milk 30. Opening the aeration valve 26a, 26b will cause the milk supply line

15a, 15b are aerated and the siphon operation is ended.

It is noted that for the purpose of this function not any position of the aeration valve 15a, 15b is allowed. When the aeration valve 15a, 15b is located in the portion 48a, 48b of the conduit 15a, 15b, the aeration valve should be at a height, in use, above the level of the liquid surface in the carton of concentrated milk. If this were not the case, the concentrated milk would flow out via the aeration valve itself. If, on the other hand, the aeration valve is arranged in the flexible part of 46a, 46b of the pipe 15a, 15b, it must be arranged above the level of the liquid surface for the same reason. In order to be able to properly perform both functions, the aeration valve will preferably be arranged at least at a height which is above the second end of the relevant milk supply line.

Ideally, however, as shown in Figure 2, the aeration valve is located at the highest point of the respective concentrate supply pipe, since it can then always function properly regardless of the liquid level in the milk carton.

The emulsifying device 12 will now be explained in more detail with reference to Figure 3. As already mentioned, the emulsifier is provided with the first and second water inlet 56a and 56b and a first and second concentrate inlet

54a and 54b. The emulsifier further includes an air inlet 72 which in this example is in direct communication with the first concentrate inlet 54a. This air inlet 72 is further provided with an adjustable valve 74 for controlling the magnitude of the air flow through the air inlet 72.

The emulsifier further includes a first venturi chamber 76a and a second venturi chamber 76b. The first and second venturi chambers 76a and 76b are spatially separated. The first water inlet 56a opens into the first venturi chamber 76a. The second water inlet 56b opens into the second venturi chamber 76b. The first concentrate inlet 54a and thus also the air inlet 72 also open into the first venturi chamber 76a. The second concentrate inlet 54b opens into the second venturi chamber 76b. The first and second venturi chambers 76a, 76b are further in fluid contact with a vortex chamber 78 through outlet 77a and 77b of the venturi chambers 76a and 76b, respectively. The whirl chamber 78 comprises a bottom 80 which is provided with an outlet in the form of an opening 82. Via this outlet 82, the whirl chamber 78 opens into a distribution chamber 84 situated below the whirl chamber. Distribution chamber 84 includes a bottom with a first and second outlet channel 86a and 86b with a first and second outlet opening 88a, 88b, respectively.

As can be seen in Figure 3f, the first and second concentrate inlet, the first and second water inlet, the whirl chamber 78, the distribution chamber 84 and the bottom 80 together with the other components of the emulsifier can be assembled from separate parts. However, this is not essential to the invention and is only intended to illustrate a possible embodiment.

The operation of the device for carrying out the method according to the invention is as follows. It should be noted in advance that in this example the first and second outlet openings 88a and 88b of the emulsifying device 12 are placed in close proximity to each other that these two outlet openings can directly deliver liquid in one cup. If it is now a user's wish to prepare frothed milk for a cup of cappuccino, the control unit 34 will activate the water generator 16 to prepare hot water. The heated water is supplied via the

0071 67 water line 18 is supplied to the selection means 20. The control unit 34 controls the selection means 20 such that the water is supplied only to the first follow-up line 22. No water is therefore supplied to the follow-up line 24. As a result, the first water inlet 56a of the emulsifier 12 is supplied with water. The water will enter the first venturi chamber 76a. This will create an underpressure in this venturi chamber since the venturi chamber 76a will function as a venturi system. As a result, the first venturi chamber 76a will draw in concentrated milk and air through the concentrate inlet 54a and the air inlet 72, respectively. The combination of concentrated milk, air and warm water will then flow at a high velocity to the whirl chamber 78 where the respective ingredients are well mixed together and whipped into foam. Turbulent vortices occur in the whirl chamber. The bottom 80 with the opening 82 of the swirl chamber functions here as a hold-up which ensures that the residence time of the mixture in the swirl chamber 78 is long enough for the concentrated milk to be properly heated under the influence of the water and under the influence of the air. will form foam. The end result is that frothed milk is supplied to the distribution chamber 84. This frothed milk will leave the distribution chamber through the outlet openings 88a and 88b and fill a cup placed under these outlet openings. To control the nature of the frothed milk, the air flow through the controllable valve 74 can be further adjusted if desired. This can still be done manually.

According to the method carried out with the device 1, milk concentrate and water are therefore combined in this example with the aid of a venturi chamber. In this example, air is also drawn in through the venturi chamber. The venturi chamber, which is in fluid communication with the whirl chamber, delivers the concentrated milk, warm water and air to the whirl chamber at high speed. In the whirl chamber, the milk concentrate and water are whipped into foamed milk as a result of eddy currents in the whirl chamber. The ratio between the amount of milk concentrate and the amount of water supplied to the venturi chamber 76a, as well as the temperature of the milk concentrate and the water, are coordinated such that the frothed milk leaving the swirl chamber is warm. For example, the foamed milk leaving the swirl chamber can have a temperature of at least 50 ° C, while the concentrated milk supplied to the venturi chamber has a temperature of, for example, 10 ° C. The ratio between the amount of milk concentrate and the amount of water supplied to the venturi chamber 76a is predetermined. This can be adjusted, for example, by choosing the diameter of the said supply lines. However, it is also possible to provide controllable valves in one or more of the pipes 22, 24, 15a or 15b to adjust the said ratio. It is also possible that the ratio between the amount of milk or coffee concentrate and the water supplied to the venturi chamber, respectively, as well as the temperature of the milk or coffee concentrate and the water, respectively, are coordinated to predetermine the temperature of the frothed milk or café crème that leaves the whirl chamber.

When the intention is to prepare hot milk that does not foam explicitly, the control unit 34 will again activate the hot water generator 16 as described above. However, the control unit 34 now controls the selection means 20 such that the water is supplied to the second follow-up line 24 while no water is supplied to the first follow-up line 22. As a result, water is supplied only to the second water inlet 56b of the emulsifier 12. This water will flow to the second venturi chamber 76b. Thus, in the second venturi chamber 76b, which again functions as a venturi system, an underpressure is generated through which concentrated milk is drawn in through the second concentrate inlet 54b. Because the second venturi chamber 76b is separated from the first venturi chamber 76a, no air will be drawn into the second venturi chamber 76b. Thus, a mixture of concentrated milk and hot water will flow from the second venturi chamber 76b to the swirl chamber 78. Also in the whirl chamber 78 no air will be drawn in via the air inlet 72. After all, an overpressure is created in the whirl chamber 78, so that it is not possible for liquid or air to flow from the first venturi chamber to the whirl chamber. In the swirl chamber 78, the milk is then mixed well with the hot water, the residence time of the concentrated milk in the swirl chamber being sufficient for a considerable heat transfer between the hot water and the concentrated milk. The bottom 80 with the opening 82 again functions as a hold up. The concentrated hot milk will then flow to the distribution chamber 84 and leave the distribution chamber distributed over the outlet openings 88a and 88b. Therefore, in the cup placed under the milk outlet openings 88a, 88b, it will be filled with hot milk that does not foam.

If it is desired with the above-described device to carry out a method according to the invention for preparing café crème, the carton of concentrated milk is replaced by a carton of concentrated coffee. For preparing café crème, the operation of the device is entirely analogous to the device as described for preparing frothed milk. This therefore means that the coffee concentrate and water are brought together using the venturi chamber 76a. Hot water is supplied under pressure via the first water inlet 56a to the venturi chamber 76a, so that a negative pressure is created in the venturi chamber 76a.

Because the first concentrate inlet 54a has been brought into fluid with the stock of coffee concentrate contained in the package 30, as a result of the underpressure in the first venturi chamber 76a, coffee concentrate is sucked into the first venturi chamber 76a via the first concentrate inlet 54a. The coffee concentrate and the hot water flow together via the outlet 77a to the whirl chamber 78. At the same time, air is also drawn in through the air inlet 72 through the venturi chamber 76a. This one

007167 air also flows to the whirl chamber. In the whirl chamber, the coffee concentrate, hot water and air are thus beaten into café crème.

Incidentally, it is also possible with the device as described above to prepare ordinary coffee. In that case, the coffee concentrate is supplied to the second venturi chamber 76b, as described above in relation to non-frothed milk. The method of preparation is also entirely analogous. It should be noted that the ratio between the amount of coffee concentrate and the water supplied to the venturi chamber, as well as the temperature of the coffee concentrate and the water, can again be coordinated such that the cafe cream leaving the swirl chamber has a predetermined temperature and for example, is warm.

Here, too, the temperature of the café crème can for instance be at least 50 ° C, while the temperature of the coffee concentrate which is supplied to the venturi chamber is, for example, 10 ° C.

The method according to the invention is in no way limited to the above-described embodiments. For example, it is also possible that instead of hot water, unheated water is supplied under pressure to the venturi chamber 76a or 76b. In that case, non-heated ready-to-drink beverages are prepared.

Such variants are each considered to fall within the scope of the invention.