WO2022090866A1

WO2022090866A1 - Device and method for rehydrating a powder of a lyophilized solid food

Info

Publication number: WO2022090866A1
Application number: PCT/IB2021/059612
Authority: WO
Inventors: Milko ZANINI; Annamaria BAGNASCO; Gianluca CATANIA; Loredana SASSO; Giancarlo ICARDI; Stefania RIPAMONTI; Flavio BAUDIZZONE; Roberto BAUDIZZONE
Original assignee: Universita' Degli Studi Di Genova; Fa.Ba. Sas; Stefania RIPAMONTI
Priority date: 2020-10-27
Filing date: 2021-10-19
Publication date: 2022-05-05
Also published as: IT202000025501A1; EP4236696A1

Abstract

The invention consists of a device (1) and a method for rehydrating a powder of a lyophilized solid food, wherein said device (1) comprises a tank (11), into which water can be introduced, a loading duct (13,13'), into which said powder of said lyophilized solid food can be introduced, a mixing chamber (17) in communication with said tank and said loading duct (13,13'), memory means containing at least mixing data defining at least an amount of water and/or an amount of powder of said lyophilized solid food that has to be introduced into said mixing chamber over time, and control means (20) configured to control a supply of said water and/or of said powder of lyophilized solid food in the mixing chamber on the basis of said mixing data.

Description

TITLE: "DEVICE AND METHOD FOR REHYDRATING A POWDER OF A

LYOPHILIZED SOLID FOOD"

DESCRIPTION:

The present invention relates to a device and a method for rehydrating a food-grade lyophilized powder, i.e. a powder of a lyophilized solid food; in particular, a lyophilized powder of a lyophilized solid food used for the preparation of a portion of food that can be eaten by a patient affected by dysphagia, i.e. suffering from a disorder of the digestive system that causes difficult swallowing and does not allow the bolus to pass correctly through the upper digestive tracts.

As is known, protein-energy malnutrition (PEM) (also at the patient's home) is still a very important problem, both for the broadness of the phenomenon and for its clinical and welfare implications, as described in the article "ZANINI , Milko, et al. Returning to the sacred - the importance of careful attention to patients' nutritional needs in hospital settings . Journal of Advanced Nursing, 2017, 73.3: 523-526" .

People suffering from deglutition deficit are particularly subject to the risk of malnutrition. This population category includes persons of any age, particularly frail elderly individuals, but also neurological patients affected by dysphagia following surgery, patients under antiblastic therapy developing mucositis, and patients that are already sarcopenic (Bressan, V. , Bagnasco, A. , Aleo, G. , Catania, G. , Zanini, M. P. , Timmins, F. , & Sasso, L. (2017) . The life experience of nutrition impact symptoms during treatment for head and neck cancer patients: a systematic review and metasynthesis. Supportive Care in Cancer, 25(5) , 1699-1712) .

In addition to the risk of suffocation caused by inability to manage the alimentary bolus, each one of such individuals is at risk of developing ab-ingestis pneumonia caused by food particles that may be sucked into the respiratory system due to incomplete occlusion of the trachea while swallowing.

As a matter of fact, the presence in the meal of multiple textures that are poorly, or not at all, tolerated by persons suffering from the above-described disorder increases the probability of direct complications of dysphagia. This condition requires the adoption, either for a recovery period, if it follows surgery, or for life, of a diet based on modified texture foods (MTF) having viscosity, density and texture properties that are compatible with the individual's residual capabilities.

The diets of patients suffering from deglutition deficit can be divided into two main categories:

- diets consisting of autologous preparations, based on whipping or homogenizing foods prepared in traditional ways, mixed with diluents, such as water or broth, and chemical or natural thickeners, in order to obtain the desired texture, density and viscosity;

- industrial preparations in the form of semifinished foods or "ready meals" which are administered after having been brought to the density recommended by the producer by heat treatment or reconstitution, or ready for use.

The use of autonomously prepared products (autologous preparations) implies a number of problems related to the alimentary technology applied in order to modify the texture of the food; such problems are the following:

- dilution of the food by addition of liquids;

- increased volume of the preparation due to incorporation of air during food centrifugation, resulting in difficulty in maintaining the desired texture throughout the meal with no phase separation.

Since these preparations are created by a (human) operator who handles the food, it is very difficult to obtain a standardized final product (i.e. modified texture food) , i.e. a product that will maintain its chemical-physical characteristics (e.g. density) over time and, most importantly, when production is repeated; in fact, the intervention of the human operator who is preparing the food may, as is often the case, modify the food's viscosity, texture, density and particle size, thus modifying the very parameters that the product should comply with in order to meet the user's (i.e. the patient's) requirements .

Lyophilized or dehydrated products are currently available on the market, but standard preparation is only envisaged for large care facilities where a considerable number of people are involved because, although the machines employed therein for preparing modified texture foods are big and hence not very flexible, since they prepare dozens of food portions at the same time, they nevertheless permit the use of standard measurement instruments, such as densimeters, that make it possible to obtain a high-quality preparation; such machines cannot, therefore, be used for preparing meals for patients at home. Indeed, the homes of such patients may also be far away from these machines, so that it would be impossible to serve three hot meals every day.

It must be pointed out that such preparations, even those served at home, must comply with density characteristics specified by international and European standardization frameworks, i.e. such preparations must have a texture level "3" or "4" (see Figure 1 from article "CICHERO, Julie AY, et al. Release of updated International Dysphagia Diet Standardisation Initiative Framework (IDDSI 2.0) . Journal of texture studies, 2020, 51.1: 195") .

The present invention aims at solving these and other problems by providing a device for rehydrating a food-grade lyophilized powder .

Furthermore, the present invention aims at solving these and other problems by providing a method for rehydrating a foodgrade lyophilized powder.

The basic idea of the present invention is to control, via control means, a supply of said water and/or said lyophilized powder in a mixing chamber on the basis of mixing data defining how much water and/or how much lyophilized powder must be introduced into said mixing chamber over time.

It is thus possible to obtain a single portion of modified texture food having desired physical characteristics (such as viscosity, texture, density and particle size) regardless of the environmental conditions and the ability level of the operator preparing the portion. Modified texture foods can thus be prepared at home, without requiring the use of measurement instruments, e.g. densimeters or the like, like those typically employed in industrial environments, where foods are prepared in much larger quantities; it should be noted, in fact, that measuring the density or the texture of a single portion of modified texture food (MTF) is a very complex, if not impossible, task, since it is impossible, for example, to immerse a densimeter into a single portion of modified texture food (MTF) , which typically has a volume that, depending on the lyophilized preparation in use, may preferably range from 150 to 500 milliliters, and even more preferably from 150 to 180 milliliters .

Further advantageous features of the present invention will be set out in the appended claims.

These features as well as further advantages of the present invention will become more apparent in the light of the following description of a preferred embodiment thereof as shown in the annexed drawings, which are provided merely by way of nonlimiting example, wherein:

- Fig. 1 shows a schematic representation of the different textures of foods and drinks according to the state of the art ;

- Fig. 2 shows a perspective view of a device for rehydrating a food-grade lyophilized powder according to the invention; - Fig. 3 shows a block diagram representing the components of the device of Fig. 2;

- Fig. 4 is a perspective view of a variant of the device of Fig . 2.

In this description, any reference to "an embodiment" will indicate that a particular configuration, structure or feature is comprised in at least one embodiment of the invention. Therefore, expressions such as "in an embodiment" and the like, which may be found in different parts of this description, will not necessarily refer to the same embodiment. Moreover, any particular configuration, structure or feature may be combined as deemed appropriate in one or more embodiments. The references below are therefore used only for simplicity's sake, and shall not limit the protection scope or extension of the various embodiments .

With reference to Figures 2 and 3, the following will describe a device 1 for rehydrating a food-grade lyophilized powder according to the invention.

The device 1 according to the invention comprises the following elements :

- a tank 11, into which water can be introduced;

- a loading duct 13, into which said lyophilized powder can be introduced;

- a mixing chamber 17 in communication with said tank 11 and said loading duct 13;

- memory means (e.g. a fixed or removable flash, SSD, etc. memory) containing at least mixing data defining at least an amount of water and/or an amount of lyophilized powder that has to be introduced into said mixing chamber over time;

- control means 20 (e.g. a CPU, a microcontroller of the

ATmegaxxxx, ESPxxxx, etc. family) suitably interfaced to control a supply of said water and/or of said lyophilized powder in the mixing chamber on the basis of said mixing data; such control means 20 may also comprise memory means.

The device 1 preferably comprises a boxed body 30, inside of which the above-described elements are positioned, so as to allow the device 1 to operate safely within a domestic environment; said boxed body 30 comprises a cavity 31, in the lower portion 311 of which it is possible to fit, preferably in a removable manner, a support surface 18 whereon a container (not shown in the annexed drawings) can be positioned, such as a dish P or the like, which will receive a portion of modified texture food prepared by the device 1, as will be further described hereinafter.

In the lower portion 311 of the cavity 31 a collection container (not shown in the annexed drawings) is preferably also positioned, under the support surface 18; the support surface 18 preferably comprises one or more apertures that permit collecting any spilled lyophilized liquid and/or food into said collection container.

This is useful to avoid soiling or damaging any objects in the vicinity of the device 1 if the container is not positioned on the support surface 18 or if said container is too small to contain a whole portion of modified texture food; the device 1 is, therefore, suitable for household use.

When the device 1 is in operation, it is possible to execute a method for rehydrating a food-grade lyophilized powder according to the invention, which comprises the following phases :

- a loading phase, in which a volume of water is introduced into a tank 11, and an amount of said food-grade lyophilized powder is introduced into the loading duct 13,

- a mixing phase, in which a supply of said water and/or of said lyophilized powder in the mixing chamber 17 is controlled, via control means, on the basis of said mixing data . In this way, it is possible to obtain a single portion o f modi fied texture food having desired physical characteristics ( such as viscosity, texture , density and particle si ze ) regardless of the environmental conditions and the abi lity level of the operator preparing the portion . This makes it possible to prepare modi fied texture food at home .

More in detail , the mixing chamber 17 preferably has a cylindrical or conical shape and comprises an opening 171 on the bottom, said chamber 17 allowing the lyophili zed powder to be mixed with the dilution liquid (preferably water ) through a suitable mixing mechanism . Such mechanism is use ful for preparing the mixture at best , advantageously reducing the inclusion of air in the preparation, thus optimi zing the result in terms of the ratio between food quantity and volume .

Therefore , the opening 171 faces towards the support surface 18 , whereon a dish P or another type of container can be positioned for receiving the portion of modi fied texture food prepared by the device 1 and ready for eating .

When the device 1 is in operation, water can be introduced through a noz zle in the upper part of said chamber, so as to increase the velocity of the intake flow . This makes it poss ible to generate a vortex ins ide said mixing chamber 17 , into which the powder of lyophili zed solid food is advantageously poured, which, as it comes in contact with a water flow moving at a certain velocity, will be rehydrated without , advantageously, forming any lumps ; moreover, any lumps in the powder will be advantageously reduced by friction with the walls of said mixing chamber 17 . When the powder has been completely rehydrated, the preparation will slow down, accumulating on the bottom of the mixing chamber 17 , which it will exit by gravity through the opening 171 .

It must be pointed out that the mixing chamber preferably comprises also a drain valve controlled by the control means 20 and capable of obstructing or clearing the opening 171 . By closing the drain valve it is possible to fully load (e.g. by controlled flow supply) the lyophilized powder into the mixing chamber and gradually add the water as specified by the mixing data; in fact, the loading duct 13 may have a rectangular or cylindrical cross-section, thus exerting no dosing action.

Furthermore, the mixing chamber 17 may also comprise an impeller (e.g. a magnetic stirrer or the like) positioned therein and configured to impart a whirling motion to the water and to the food powder suspended in said water.

In this way it is advantageously possible, by controlling the supply of water, to attain repeatability of the process of preparing a single portion of modified texture food having desired physical characteristics (such as viscosity, texture, density and particle size) regardless of the environmental conditions and the ability level of the operator preparing the portion, thus making it possible to prepare modified texture food at home.

The mixing data, which, as aforesaid, define how much water and/or how much lyophilized powder has to be introduced into said mixing chamber over time, may comprise a set of numbers, each one specifying the volumetric (or mass) flow rate of water or powder at a given instant; as an alternative, the mixing data may also comprise a set of number pairs, each pair specifying the volumetric (or mass) flow rate of water and lyophilized powder at a given instant.

Furthermore, the mixing data may also define a ratio between water and lyophilized powder that must be observed while preparing a certain type of food (e.g. 4-5 grams of water per 1 gram of lyophilized food) .

In addition to the above, as will be further described below, said mixing data may also define the revolution speed of the impeller and the temperature of the water delivered into the mixing chamber 127.

It will nevertheless still be possible for those skilled in the art to define the mixing data in a manner alternative to the above, without however departing from the teachings of the present invention.

In addition to the above, the device 1 may also comprise communication means for communicating across a network, preferably a network interface operating in accordance with a standard of the 802.11 (also known as WiFi) , 802.16 (also known as WiMax) , IEEE 803.2 (also known as Ethernet) , 802.15 (also known as Bluetooth) families, or an interface to a data network of the GSM/GPRS/UMTS/LTE, TETRA, etc. types) , through which the above-described mixing data can be updated. In other words, the control means (which may also comprise said communication means) are preferably configured to receive, by means of said communication means, the mixing data (preferably from a server) and to store said mixing data into the memory means.

In this way, the mixing data of said device 1 can be updated remotely, so that it will always be possible to obtain single portions of modified texture food having desired physical characteristics (such as viscosity, texture, density and particle size) even when the food composition is changed, thus making it possible to prepare modified texture food at home in full safety.

In combination with or as an alternative to the above, the mixing data can be changed according to the type of modified texture food to be prepared. This can be done manually, preferably via a specific menu of the user interface 119, e.g. by specifying the water/powder ratio that must be maintained during the preparation; in fact, the mixing data may also be generated, by the control means 20, on the basis of physical characteristics (such as, for example, viscosity, texture, density and particle size) that the rehydrated food (i.e. the rehydrated lyophilized solid food) must have when it is ready for eating.

As an alternative to or in combination with the manual entry of the data, the device 1 may also comprise an image sensor capable of acquiring an image representing a portion of a container (which preferably contains the lyophilized powder to be loaded into the device 1) whereon a bar code, preferably a two-dimensional one (e.g. a QR code) , is present; to this end, the control means 20 are preferably also configured for executing (prior to the mixing phase) :

- an acquisition phase, in which a bar code is extracted by means of said image sensor, and coded information is preferably extracted from a graphic representation of said bar code, e.g. by executing (or having another processor execute) an image recognition algorithm;

- a determination phase, in which the mixing data are determined on the basis of said bar code or the coded information in said bar code, e.g. by using the coded information in said bar code in order to recognize the type of food-grade lyophilized powder in use and then retrieve, from the memory means, the mixing data associated with said powder, or by (directly) extracting the mixing data from the coded information in said code.

The mixing data can thus be adapted to the type of modified texture food to be prepared, so that it will always be possible to obtain single portions of modified texture food having desired physical characteristics (such as viscosity, texture, density and particle size) even when the food composition is changed, thus making it possible to prepare modified texture food at home in full safety.

During the loading phase, the water that is introduced into the tank 11 preferably comes from a water network R, through which drinking water is supplied. For this purpose, the tank 11 comprises an inlet valve 111, which can be put in communication with the water network R, and a level sensor (e.g. a float, a magnetic sensor, or the like) configured to detect a level of the tank 11 and to activate (whether directly, e . g . by a force generated by the hydrostatic thrust received from a float , or indirectly, by generating an electric signal ) said inlet valve 111 , so as to obtain a constant supply of water to the tank 11 without the user of said machine 1 having to take care of it .

I f the inlet valve 111 is not present , or i f said level sensor is not directly connected to said valve ( as would be the case when using a magnetic sensor ) , said level sensor may be put in communication with the control means 20 , which may preferably be configured to inhibit the preparation of food when the level detected by said sensor is below a threshold . I t will thus possible to advantageously inhibit the preparation o f food unti l the user manual ly restores the correct water level in the tank 11 .

In this way, a situation cannot arise in which the water level in the tank is too low, thus preventing the preparation of food with too little water ; as a matter of fact , such a situation would lead to the preparation o f a portion of modi fied texture food having improper texture/density, which would be unsafe for the patient . It i s thus pos sible to obtain a single portion of modi fied texture food having desired physical characteristics ( such as viscosity, texture , density and particle si ze ) regardless of the environmental conditions and of the ability level of the operator preparing the portion, so that modi fied texture food can be prepared at home in full safety .

In combination with the above , the device 1 preferably comprises also a control interface 19 in communication with the control unit 20 , e . g . via an SPI serial bus or the like ; said interface comprises a display 191 , preferably a liquid-crystal touchscreen display, and/or buttons 192 that allow at least turning on, activating and stopping the device 1 . The presence of the display 191 is especially important , in that the control unit 20 can be configured to send, through the display 191 , support messages to the user of the device 1 , describing the steps to be carried out in order to prepare a portion of modified texture food, so as to reduce the risk of mistakes while preparing the food portion, which would make it unsafe for the patient .

In combination with the above, the device 1 preferably comprises also a pumping assembly 12 configured to pump water from the tank 11 to the mixing chamber 17.

More in detail, the pumping assembly 12 (and hence the device 1) comprises a pump 121 positioned downstream of the tank 11 and upstream of the mixing chamber 17; said pump 121 is preferably of the volumetric type (volumetric pump) , so that the control unit 20 can control the flow rate (and hence the volume) of water introduced into the mixing chamber 17. This makes it possible to prepare a portion of modified texture food without formation of lumps during the mixing phase; in fact, if there is too much water in the mixing chamber 17, there is a risk that the lyophilized powder might float on the surface of the water, thus forming lumps; conversely, if there is too little water, there is a risk that some of the lyophilized powder might not be reached by the water. The presence of lumps must be absolutely avoided because it might trigger rejection by the patient.

In this way, it is possible to obtain a single portion of modified texture food having desired physical characteristics (such as viscosity, texture, density and particle size) regardless of the environmental conditions and of the ability level of the operator preparing the portion, so that modified texture food can be prepared at home in full safety.

In addition, the pumping assembly 12 (and hence the device 1) preferably comprises also anti-backflow means 122 (e.g. an antibackflow tray also known as "air break", or the like) positioned downstream of the tank 11 and upstream of the pump 12, i.e. between the suction duct of the pump 12 and the tank 11. This makes it possible to keep a constant pressure on the intake duct of the pump 121, in addition to preventing suction of air into said pump and then into the mixing chamber 17.

In addition to preserving the integrity of the pump 121, this also ensures better control over the water volume supplied into the mixing chamber, making it possible to obtain a single portion of modified texture food having desired physical characteristics (such as viscosity, texture, density and particle size) regardless of the environmental conditions and the ability level of the operator preparing the portion, so that modified texture food can be prepared at home.

Furthermore, the pumping assembly 12 (and hence the device 1) preferably comprises also a filter 123 positioned downstream of the tank 11 and upstream of the pump 121 (and of any antibackflow means) , i.e. between the suction duct of the pump 121 and the tank 11. This filter 123 prevents any solid particles coming from the water network R from entering the device 1, thus damaging it, or, even worse, from reaching the mixing chamber 17 and, from there, the portion of modified texture food that the device 1 is preparing. Such solid particles may have a considerable size and, should they end up into the food being prepared, could adversely affect the swallowing of the bolus by the patient.

In addition to preserving the integrity of the pump 121 and of the entire device 1, this also prevents particles from entering the mixing chamber 17, making it possible to obtain a single portion of modified texture food having desired physical characteristics (such as viscosity, texture, density and particle size) regardless of the environmental conditions and the ability level of the operator preparing the portion, so that modified texture food can be prepared at home in full safety.

In addition to the above, the device 1 preferably comprises also a heater 14, preferably an electric one, positioned upstream of the mixing chamber 17 and, preferably, downstream of the pumping unit 12; said heater 14 is configured to heat a water flow that, starting from the tank 11, is delivered into the mixing chamber 17, preferably through a nozzle (not shown in the drawings) . The thermal power generated by the heater 14 is preferably controlled by the control unit 20, so that said control unit 20 can control the temperature of the water flow entering the mixing chamber 17. It is thus possible to dissolve the lyophilized powder into water having an optimal temperature (78-92°C) , thereby preventing the formation of powder lumps in the portion of modified texture food being prepared.

In addition to the above, the device 1 preferably comprises also a solenoid valve 15 positioned upstream of the mixing chamber 17 (and downstream of the pumping unit 12) and in communication with the control unit 20, wherein said control unit 20 is configured to open the solenoid valve 12 (e.g. by supplying power thereto) only when the pump 121 is in operation. This prevents air from entering the pumping unit 12, thus advantageously avoiding the introduction of any error in the control of the water volume supplied to the mixing chamber 17; moreover, due to the presence of the solenoid valve 15, the pump 121 and the anti-backflow means 122, the solenoid valve 15 can also be used for venting any air that may be present in the circuit without supplying water to the mixing chamber 17. To do so, the control unit can be configured for closing the solenoid valve 15 (e.g. by switching off the power) and for activating the pump 121, thereby causing any air to flow up into the antibackflow means 122 and out into the atmosphere.

Of course, the example described so far may be subject to many variations .

A first variant is shown in Fig. 4; for brevity, the following description will only highlight those parts which make this and the next variants different from the above-described main embodiment; for the same reason, wherever possible the same reference numerals, with the addition of one or more apostrophes, will be used for indicating structurally or functionally equivalent elements.

A device 1' that is similar to the above-described device 1 comprises a loading duct 13' having a conical, preferably a funnel-like, shape. This makes it possible to load the lyophilized powder into the mixing chamber 17 and to gradually add water as specified by the mixing data. It must be pointed out that the loading duct 13 of the previous embodiment, since it preferably has a rectangular or cylindrical cross-section, cannot exert any kind of dosing action.

This provides better control over the preparation of the modified texture food, so that it is possible to obtain a single portion of said food having desired physical characteristics (such as viscosity, texture, density and particle size) regardless of the environmental conditions and the ability level of the operator preparing the portion. Modified texture food can thus be prepared at home in full safety.

In addition to the above, the loading duct 13' of this embodiment preferably comprises also one or more loading sensors (e.g. a laser sensor, an infrared sensor, or the like) capable of detecting the loading of lyophilized powder in the loading duct 13' .

The device 1' comprises also control means which are similar to the control means 20 of the previous embodiment and which are in communication with said one or more loading sensors ; compared with those of the preceding version, said control means are al so configured to start the mixing phase when at least one of said one or more loading sensors detects the loading of the lyophili zed powder .

This further improves the preparation process , so that it is possible to obtain a single portion of modi fied texture food having desired physical characteristics ( such as viscosity, texture , density and particle si ze ) regardless of the environmental conditions and the ability level of the operator preparing the portion, so that modi fied texture food can be prepared at home in full safety .

A second variant of the device 1 comprises also an auger configured to move the lyophilized powder from the loading duct to the mixing chamber, a motor (preferably an electric direct- current or step motor, or the like ) coupled to said auger , and a control unit which is similar to the one of the main embodiment and which is also configured to control said motor on the basis of the mixing data . More in detail , i f the motor is an electric one , such motor i s controlled by the control unit 20 , which is configured to determine the amount of lyophili zed powder to be supplied into the mixing chamber 17 by appropriately adj usting motor parameters such as revolution speed and operating time . The revolution speed of the motor can be controlled either by controlling the revolution speed of the electric field ( in step motors ) or ( in direct-current motors ) by controlling a supply voltage , e . g . using pulse-width modulation ( PWM) to vary the mean value of the direct component of said supply voltage .

When the device i s in operation, the auger is rotated by the motor, whose revolution speed - as well as on/of f time - i s controlled by the control unit . This makes it pos sible to control the supply of lyophili zed powder to the mixing chamber .

This provides optimum control over the preparation of modi fied texture food, so that it is possible to obtain a single portion of modified texture food having desired physical characteristics

(such as viscosity, texture, density and particle size) regardless of the environmental conditions and the ability level of the operator preparing the portion, so that modified texture food can be prepared at home in full safety.

It must be pointed out that in this embodiment the mixing data may specify the volumetric (or mass) flow rate of the water and of the lyophilized powder over time.

Some of the possible variants of the invention have been described above, but it will be clear to those skilled in the art that other embodiments may also be implemented in practice, wherein several elements may be replaced with other technically equivalent elements. The present invention is not, therefore, limited to the above-described illustrative examples, but may be subject to various modifications, improvements, replacements of equivalent parts and elements without however departing from the basic inventive idea, as specified in the following claims.

Claims

1. A device (1,1' ) for rehydrating a powder of a lyophilized solid food, comprising

- a tank (11) , into which water can be introduced,

- a loading duct (13,13' ) , into which said powder of said lyophilized solid food can be introduced,

- a mixing chamber (17) in communication with said tank and said loading duct (13,13' ) , in which the water and the powder of said lyophilized solid food can be mixed, characterized in that it comprises

- memory means containing at least mixing data defining, for said lyophilized solid food, at least an amount of water and/or an amount of said powder of said lyophilized solid food that has to be introduced into said mixing chamber over time, and

- control means (20) configured to control a supply of said water and/or of said powder of said lyophilized solid food in the mixing chamber on the basis of said mixing data.

2. The device (1,1' ) according to claim 1, wherein the control means (20) are configured to generate the mixing data on the basis of physical characteristics that said lyophilized solid food must have when rehydrated and ready for eating.

3. The device (1,1' ) according to claim 2, wherein said physical characteristics comprise viscosity and/or texture and/or density and/or particle size.

4. The device (1,1' ) according to any one of claims 1 to 3, wherein the tank (11) comprises

- an inlet valve (111) which can be put in communication with a water network (R) , and

- a level sensor configured to detect a level of said tank (11) and to activate said inlet valve (111) .

5. The device (1,1' ) according to claims 1 to 4, comprising a pump (121) positioned downstream of the tank (11) and upstream of the mixing chamber (17) , wherein said pump (121) is of the volumetric type.

6. The device (1,1' ) according to claim 5, comprising antibackflow means (122) positioned downstream of the tank (11) and upstream of the pump (12) .

7. The device (1,1' ) according to claims 5 or 6, comprising a filter (123) positioned downstream of the tank (11) and upstream of the pump ( 12 ) .

8. The device (1,1' ) according to any one of claims 1 to 7, comprising a heater (14) positioned upstream of the mixing chamber ( 17 ) .

9. The device (!' ) according to any one of claims 1 to 8, wherein the loading duct (13' ) has a conical shape.

10. The device (1' ) according to claim 9, comprising at least one loading sensor capable of detecting a loading of the powder of the lyophilized solid food in the loading duct (13' ) , and wherein the control means are also configured to start controlling the supply of said water and/or of said powder of said lyophilized solid food in the mixing chamber when said at least one loading sensor detects the loading of the powder of said lyophilized solid food.

11. The device according to any one of claims 1 to 8, also comprising an auger configured to move the powder of the lyophilized solid food from the loading duct to the mixing chamber, a motor coupled to said auger, and wherein the control unit is also configured to control said motor on the basis of the mixing data.

12. The device (1,1' ) according to any one of the preceding claims, comprising communication means for communicating across a network, and wherein the control means (20) are also configured to

- receive, by means of said communication means, the mixing data, and

- store said mixing data in the memory means.

13. The device (1,1' ) according to any one of the preceding claims, comprising an image sensor, wherein the control means (20) are also configured to

- acquire, by means of said image sensor, a bar code, and

- determine, on the basis of said bar code, the mixing data.

14. Method for rehydrating a powder of a lyophilized solid food, comprising

- a loading phase, in which a volume of water is introduced into a tank (11) , and an amount of said powder of said lyophilized solid food is introduced into a loading duct (13, 13' ) , characterized in that it also comprises

- a mixing phase, in which a supply of said water and/or of said powder of said lyophilized solid food in a mixing chamber (17) is controlled by means of control means on the basis of mixing data, wherein said mixing data define, for said lyophilized solid food, at least an amount of water and/or an amount of powder of said lyophilized solid food which has to be introduced into said mixing chamber over time.