Recycling of evaporation products in preparation of plant-based liquid food concentrates
By recycling and reuse of evaporation products in the production process of plant-based concentrated liquid food, the problem of large resource consumption in the prior art is solved, water and energy savings are achieved, and production costs are reduced.
Patent Information
- Application Number
- CN202380063699.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2022-09-27
- Filing Date
- 2023-09-19
- Publication Date
- 2025-04-11
AI Technical Summary
The prior art consumes a lot of resources when producing plant-based concentrated liquid food, especially water and energy consumption, resulting in an increase in production costs.
Plant-based slurry is prepared by mixing plant materials and water, and after enzyme and heat treatment, the slurry is separated into solid and liquid parts, the water is evaporated from the liquid part to produce an evaporated part and a concentrated part, and the evaporated part is subsequently recovered and reused in the slurry mixture, reducing the use of fresh water, and heating the slurry mixture by heat of the recovered evaporated product.
Most of the evaporation products can be reused, significantly reducing the amount of fresh water used to produce slurries, saving water resources, and saving energy by recycling heat.
Smart Images
Figure CN119816207A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a method and a system for producing a plant-based concentrated liquid food product. Background Art
[0002] In recent years, plant-based liquid foods have become increasingly popular. In order to extend the shelf life of such products, reduce transportation costs and / or provide ingredients (bases) for plant-based beverages, plant-based liquid foods in the form of concentrated or condensed milk are usually produced, such as oat condensed milk, rice condensed milk, etc. The processing of concentrated plant-based liquid foods generally includes preparing a plant-based slurry mixture by mixing dry plant-based ingredients and water, and then evaporating water from the mixture to produce concentrated liquid foods. Although this traditional process for producing concentrated plant liquid foods is simple and relatively efficient, it is still necessary to make it more efficient, especially to reduce costs. Summary of the invention
[0003] The object of the present invention is to at least partially overcome one or more of the above limitations of the prior art. In particular, the object of the present invention is to provide a method and system for producing a plant-based concentrated liquid food using fewer resources.
[0004] To achieve at least these objectives, a method for producing a plant-based concentrated liquid food is provided, comprising the steps of: (i) preparing a plant-based slurry by mixing at least plant material and water; (ii) treating the slurry with at least one of an enzyme and heat; (iii) separating the slurry into a solid portion and a liquid portion; (iv) evaporating water from the liquid portion to produce at least one evaporated portion comprising evaporated water, and at least one concentrated portion forming a plant-based concentrated liquid food; (v) preparing a subsequent plant-based slurry by mixing at least the plant material and the evaporated portion; and (vi) repeating steps ii) to iv) for the subsequent slurry.
[0005] A system for producing a plant-based concentrated liquid food is also provided, comprising: (i) a mixer configured to prepare a plant-based slurry by mixing at least a plant material and water; (ii) a container that enables the slurry to be treated with at least one of an enzyme and heat; (iii) a separation unit configured to separate the slurry into a solid portion and a liquid portion; (iv) an evaporator configured to evaporate water from the liquid portion to produce at least one evaporated portion containing evaporated water, and at least one concentrated portion forming a plant-based concentrated liquid food; and (v) a return pipe configured to transport the evaporated portion from the evaporator to the mixer or another mixer configured to prepare a subsequent plant-based slurry by mixing at least the plant material and the evaporated portion.
[0006] Such systems and methods have the advantage that a large portion of the evaporated product can be recovered and reused in a subsequent slurry mixture, for example 85% or more of the evaporated product can be reused. The evaporated product can be primarily composed of water and can be condensed into a liquid form and then added back to a subsequent plant-based slurry mixture. The large portion of the recovered evaporated product reused in the subsequent slurry mixture replaces the amount of fresh water used to produce the slurry mixture, thereby significantly saving water.
[0007] Advantageously, the method and system can also significantly save energy by utilizing heat from the recovered evaporated product to heat the slurry mixture. This reduces the energy required to heat the fresh water added to the slurry mixture.
[0008] The recovered evaporated product can be filtered before being reused in a subsequent slurry mixture to remove contaminants or other components that may affect the quality or taste of the subsequent slurry mixture. The recovered evaporated product can be cooled before filtering to reduce the possibility of filter damage, and the heat extracted from the recovered evaporated product during the cooling process can be used to reheat the liquid added to the subsequent slurry mixture, thereby still saving energy.
[0009] Other objects, features, aspects and advantages of the present invention will become apparent from the following detailed description and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Embodiments of the present invention will now be described by way of example with reference to the accompanying drawings, in which
[0011] Figure 1 is a schematic diagram of an exemplary system for producing a plant-based concentrated liquid food according to an embodiment of the present invention.
[0012] Figure 2 is a flow chart showing an exemplary method of producing a plant-based concentrated liquid food according to an embodiment of the present invention. DETAILED DESCRIPTION
[0013] Embodiments of the present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all, embodiments of the invention are shown. The present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.
[0014] refer to Figure 1, shows an exemplary system 1 for producing a plant-based concentrated liquid food FP, wherein the system 1 generally uses a plant-based material P and water W to form a slurry S. The slurry S is separated into a solid portion SP and a liquid portion LP, wherein the liquid portion LP is evaporated to generate a concentrated portion CP in the form of a plant-based concentrated liquid food FP, and an evaporated portion EP including evaporated water. The system 1 is configured so that the evaporated portion EP is recovered together with the water and reused in a subsequent plant-based slurry mixture, thereby significantly reducing the amount of fresh water used to make subsequent slurries. The evaporated water can be returned at an elevated temperature, thereby reducing the energy used to heat the water to prepare the slurry mixture. The system 1 can also be configured to save energy by heating water or a slurry mixture by recycling heat in the process.
[0015] The system 1 includes at least one mixer 6 that receives the plant-based material P and water W and mixes them together to form a slurry mixture S. The slurry S is a mixture of solids from the plant-based material P suspended in a liquid including the water W. The mixer 6 may be a grinder, a blender, a high shear mixer, etc., or may have any suitable combination of such mixing techniques to form a slurry mixture S having its desired properties.
[0016] The plant-based material P can be added to the mixer 6 from a container 2 (e.g., a hopper), which can be suitable for conveying dry goods. The plant-based material P may include any food type or food combination suitable for making a plant-based concentrated liquid food FP. This includes but is not limited to one or more of oats, peas, soybeans, rice, beans, etc. The plant-based material P can be in any form suitable for mixing in the mixer 6, such as dry goods in the form of flour, flakes, kernels, broken grains, seeds, grains, peas, beans, nuts, etc., or any combination thereof. Additional ingredients may also be added to the mixer 6 to form a slurry S for the possible need to achieve processing, taste, nutritional content or other characteristics of the final food FP.
[0017] Water W may be added from a separate container or other source 4, such as a municipal water source. The water W is added to the mixer 6 as a liquid and may be heated before entering the mixer 6. Alternatively or additionally, the slurry S may be heated in the mixer 6, for example, using a heater that is thermally connected to the mixer 6. The temperature of the water W or slurry S in the mixer 6 may be in the range of 55° C. to 95° C. The amount of water W added to the mixer 6 depends on the desired properties of the slurry S. For example, the solid content of the slurry S may range from 10% to 35% by weight, or from 16% to 20% by weight, or more, so that the amount of water W added to the mixer 6 may range from 65% to 90% by weight, or less.
[0018] In order to convey the material through the system 1, one or more flow control devices may be provided. For example, the illustrated system 1 shows a pump 8 located downstream of the mixer 6 for conveying the slurry S downstream in the system 1. Depending on the state of the material to be conveyed, more than one pump 8 may be employed at various locations in the system. In addition, one or more valves (not shown) or other similar flow control devices may be used at various locations throughout the system 1 to control the flow of materials as desired.
[0019] At least one container 10 may be located downstream of the mixer 6 for receiving the slurry S and enabling the slurry S to be treated with enzyme E and / or with heat. That is, the slurry S may be treated with enzyme, heat, or both. Heat treatment may be performed by providing heat to the container 10, such as by using a heating jacket around the container 10. If used, the enzyme E may hydrolyze the plant-based material in the slurry S to cut starch and produce sugar. After the process, the enzyme may be deactivated in the container 10 or in a separate container downstream of the container 10. Although enzyme E is added to the container 10, enzyme E may also be directly added to the mixer 6, in which case the container 10 may be used for subsequent treatment, such as deactivation. Enzyme treatment and / or heat treatment may be performed according to known techniques commonly used for the plant material type used to form the slurry.
[0020] The separation unit 12 is located downstream of the mixer 6 and is used to receive the slurry mixture S or the enzyme-treated slurry mixture from the container 10. The separation unit 12 can be a decanter or other suitable device, which is configured to separate the slurry S into a solid part SP and a liquid part LP to obtain a liquid base with a predetermined solid content. Therefore, the terms "solid part" and "liquid part" are used in this article to distinguish the parts, wherein the solid part SP contains more solids than the liquid part LP. It is understood that the solid part SP may still contain some liquid, and the liquid part LP may still contain some solids. The solid part SP can be called the first part, and the liquid part LP can be called the second part, with the difference that the first part contains more solids than the second part. For example, the solid (first) part SP may contain at least five times more solids than the liquid (second) part. The solid content of the liquid part LP will generally vary depending on the solid matter in the initial slurry S and the upstream process. For example, the solid content in the liquid part LP can be in the range of 2% to 35% by weight, or more particularly in the range of 10% to 30%. Typically, the solids content of the liquid portion LP is about 2% less than that of the slurry S. The solids content of the solid portion SP may be about 30% to 45%.
[0021] The evaporator 18 is located downstream of the separation unit 12 and is configured to receive and evaporate at least a portion of the liquid portion LP to produce at least one evaporated portion EP and at least one concentrated portion CP. The evaporated portion EP includes evaporated water, wherein the water comes from the water W in the initial slurry mixture S. The evaporated portion EP may include greater than 97% water, or greater than 99% water, although other volatiles or molecules from the liquid portion LP may be included in the evaporated portion EP. The concentrated portion CP from the evaporator 18 forms a plant-based concentrated liquid food FP. The solid content of the concentrated portion CP used to make the final plant-based concentrated liquid food FP may range from 40% to 80% by weight, or its solids may be as high as 85% or more by weight.
[0022] The amount of water evaporated from the liquid portion LP may range from 90% to 95% by weight, or more, so that a large amount of water in the initial slurry mixture S may be recycled back to the mixer 6, or one or more other mixers 6', for reuse in preparing at least one subsequent slurry S. In addition, the evaporated water in the evaporation portion EP may leave the evaporator 18 at a high temperature (e.g., in the range of 70°C to 80°C or even higher), wherein the heated water may be used to provide heat when preparing the slurry S, thereby significantly saving energy.
[0023] In order to return and reuse the evaporated water from the evaporation part EP, a return path (e.g., a suitable return pipe 20) is fluidly connected to the output end of the evaporator 18 to transport the water in the evaporation part EP to the mixer 6, 6'. The return pipe 20 may include any number of additional processing devices suitable for the system 1, such as flow control devices, meters, branching devices, etc. In addition, the return pipe 20 may transport the evaporation part EP in the form of steam or liquid. Therefore, it should be understood that the term "evaporation part" is used herein to distinguish it from the condensation part, and after evaporation, the evaporation part EP (including the evaporated water) may be condensed into a liquid form before returning to the mixer 6, 6'. For this purpose, the evaporator 18 may generally have a condenser at its outlet for the evaporation part EP.
[0024] As shown, there are a variety of ways to return the water in the evaporated portion EP to the mixer 6, 6' and reuse it. For example, as shown via a branch fluid return line 38, after leaving the evaporator 18, the evaporated portion EP can be directly returned to the input end of the mixer 6 (or other mixer 6') without further processing through other components of the system 1. In order to provide an appropriate mass balance of evaporated water in the subsequent slurry S, the system 1 may also include at least one flow meter 32, such as a mass flow meter or a volume flow meter, arranged between the evaporator 18 and the mixer 6. In addition, in order to control the heat of the slurry mixture S, the system 1 may also include at least one temperature sensor 34 upstream of the mixer 6 to determine the heat of the recycled water added to the mixer 6.
[0025] In some cases, the evaporation portion EP may contain undesirable flavors, volatiles or other impurities, in which case the evaporation portion EP may be filtered using a suitable filter 24 to remove such impurities. The filter 24 may include a reverse osmosis filter that provides a high degree of filtration. Before reverse osmosis filtration, a pre-filter, such as a 25-micron needle filter bag, may also be used to extend the life of the reverse osmosis filter. Since some types of filters may degrade at high temperatures (e.g., at the temperature of the evaporation product EP), the system 1 may also include a cooler 22 upstream of the filter 24. The cooler 22 may include a suitable heat exchanger configured to reduce the temperature of the evaporation portion EP by the required amount before filtration, such as to a temperature of about 50°C or less. In order to save the heat energy Q extracted from the evaporation portion EP for reuse, the thermal communication line 23 may be thermally coupled to the cooler 22 and configured to transfer the extracted heat energy Q back to the recovered water before entering the mixer 6. In other cases where flavors, volatiles, impurities or other molecules from the evaporation portion EP may be needed in the subsequent slurry S, the system 1 may include a bypass line 36 that bypasses the filter 24.
[0026] A buffer tank 26 may be provided in the system 1 for receiving the evaporated portion EP from the filter 24 or via the bypass line 36 to help delink the input / output capacity of the system 1. The buffer tank 26 may also be configured to receive fresh water W from a source 28 (e.g., a container or municipal water source) to mix with the water from the evaporated portion EP to form a water mixture EP-W', which is added to the mixer 6, 6' to prepare the subsequent slurry S. The fresh water portion W' of the mixture EP-W' may at least partially compensate for the total amount of water required for the subsequent slurry mixture S. For example, adding the fresh water W' to the mixture EP-W' may make up the entire balance of the required water content in the slurry S, in which case no additional water may be required from the source 4. Alternatively, additional water W may be added from the initial source 4. Although the initial source 4 is shown, the system 1 may also use only water W' from the source 28 (via the buffer tank 26) for the initial slurry mixture S, in which case no source 4 is required at all.
[0027] Because the fresh water W added from the source 28 may be at a lower temperature than that required for preparing the slurry S, a heater 30 may be provided downstream of the buffer tank 26 to heat the water mixture EP-W' before adding it to the mixers 6, 6'. The heater 30 may heat the water mixture EP-W' to a temperature in the range of, for example, 55° C. to 85° C. As described above, heat Q from the cooler 22 (if used) may be added to the mixture EP-W' to reduce the amount of heat required by the heater 30 to heat the mixture EP-W' to the desired temperature.
[0028] The flow meter 42 may be located between the buffer tank 26 and the mixer 6 to determine the mass balance of the water mixture EP-W' to be added to the mixer 6 to prepare the subsequent slurry S. The flow meter 42 may be coordinated with a suitable flow control device (e.g., a valve) or a suitable control circuit (e.g., an electronic controller) to determine and meter the amount of the water mixture EP-W' to be added to the mixer 6 to achieve the desired total water content of the slurry S. The flow meter 42 may also be coordinated with the flow meter 32 between the evaporator 18 and the buffer tank 26 to determine the input and output of water from the tank 26, which may help determine the amount of fresh water W' to be added to the tank 26. In addition, the temperature sensor 34 may also be used to control the amount of fresh water W' in the mixture EP-W' or to control the heater 30 to achieve the desired temperature of the slurry S.
[0029] System 1 is shown as a continuous cycle process, in which the evaporated portion EP is continuously produced from the liquid portion LP of the slurry S and returned to the mixer 6 or another mixer 6' to produce a subsequent slurry S. Therefore, the subsequent slurry will include at least some water from the evaporated portion EP, and then the evaporated water portion is evaporated and circulated back to the other subsequent mixture. By adding fresh water W' or W, the process may run for hours or days, depending on the need to clean the machine, replenish raw materials or the like. In addition, since the evaporated water is constantly circulated and evaporated again, there may be an accumulation of undesirable concentrations of impurities, which can be filtered with a filter 24, or the system may need to be flushed by using fresh water W or W' or a special cleaning agent. Although shown as a continuous process, it should be understood that system 1 can also be used as a semi-continuous process or a batch process while still providing advantages in water conservation. For example, the water in the evaporated portion EP can be stored in a separate container after evaporation and can then be used as the total water content in one or more subsequent slurry mixtures S, for example by filling the source (container) 4 with evaporated water from the evaporation portion EP. Other variations using water from evaporation section EP are possible with the exemplary system.
[0030] Go to Figure 2 , a flow chart of an exemplary method 100 for producing a plant-based concentrated liquid food FP using recycled water is shown. The method 100 may begin with a step of preparing 102 a plant-based slurry S by mixing at least a plant material P and water W. The slurry S may be prepared at an elevated temperature, for example, by heating the water W or heating the slurry S. The temperature may be in the range of 55° C. to 85° C., which may depend on the plant-based material P. For example, an oat-based slurry may be processed at a temperature in the range of 55° C. to 75° C., while a rice-based slurry may be processed at a temperature of about 85° C.
[0031] In step 106, the slurry S may be treated with an enzyme E that can hydrolyze the plant material P. The enzyme treatment may occur over a time span of 2, 4, 6, or even up to 15 hours. Generally, the amount of enzyme added may be less than 1% of the total slurry weight. After the enzyme treatment, the enzyme may be inactivated. Alternatively or additionally, in step 106, the slurry S may be heat treated appropriately depending on the type of plant-based concentrated liquid food being prepared.
[0032] Step 110 comprises separating the slurry S into a solid portion SP and a liquid portion LP, wherein the solid portion SP may comprise fibrous material separated from the plant-based material P. The solid content in the liquid portion LP may be, for example, in the range of 10% to 30% by weight, the remainder being water from the slurry mixture S.
[0033] Step 116 includes evaporating water in the liquid portion LP to produce an evaporation portion EP and a concentrated portion CP. About 80% to 95% or more of the water in the liquid portion LP may be evaporated and contained in the evaporation portion EP. The temperature of the evaporated water may be in the range of 70° C. to 90° C. About 99% or more of the evaporation portion EP may be evaporated water, and the remainder may be impurities, such as volatiles or other molecules from the solid portion.
[0034] In step 116, a large amount of the water content in the liquid portion LP is evaporated, which water content can be reused in the subsequent slurry S. Two theoretical mass balance examples are provided below to illustrate the amount of water that can be removed and reused in this process, these examples are for illustration only and are not limiting: Embodiment 1:
[0035] The liquid part LP of the oat-based slurry S (whose solid content is 15% by weight) is fed to the evaporator at 20,000 kg / h to form an evaporation part EP and a condensation part CP, wherein the solid content of the condensation part CP is 75% by weight. This means that 16,000 kg / h of water (or 94% of the water) is removed from the liquid part LP, which can be recovered and reused in the subsequent slurry mixture. The following Table 1 illustrates this embodiment:
[0036] Table 1: Mass balance calculations for Example 1 Embodiment 2:
[0037] The liquid part LP of the oat-based slurry S (whose solid content is 25% by weight) is added to the evaporator in an amount of 20,000 kg / h to form an evaporation part EP and a condensation part CP, wherein the solid content of the condensation part CP is 75% by weight. This means that 13,350 kg / h of water (or 89% of the water) is removed from the liquid part LP, which can be recovered and reused in the subsequent slurry mixture. The following Table 2 illustrates this embodiment:
[0038] Table 2: Mass balance calculations for Example 2
[0039] As described above, the solid content of the input liquid portion LP can be in the range of 10% to 30%, but can also be 2% to 35%. The solid content of the output condensed portion CP used to make the final food product FP can be in the range of 70% to 85%, but can also be 60% to 95%. Such ranges can be used in the above examples to determine the amount of water that can be saved when using the exemplary method 100.
[0040] After step 116, method 100 may include cooling the evaporated product EP at step 122. Cooling step 122 may reduce the temperature of the evaporated product to a level that does not damage the filter or other downstream components of the system. Step 126 may include filtering the evaporated product to remove impurities.
[0041] Step 130 includes buffering the evaporated product EP, which may include mixing the evaporated product EP with fresh water W' in a tank. After the buffering step 130, the process may include a heating step 134 to increase the temperature of the evaporated product EP or the mixture of evaporated product and fresh water EP-W'.
[0042] At various times, for example after the heating step 134, the method 100 may include a step 140 of measuring the temperature of the evaporated portion EP or the temperature of the mixture EP-W' to which the evaporated portion EP belongs before a step 144 of preparing a subsequent plant-based slurry (S). In addition, the method 100 may include a step 142 of measuring the amount of the evaporated portion EP before preparing 144 a subsequent plant-based slurry S at various times. These steps 140 or 142 may be used to prepare 144 a mass balance of the water content in the subsequent slurry S, or may be used to provide a predetermined slurry S temperature.
[0043] Step 144 includes preparing a subsequent plant-based slurry S by mixing the plant material P and the evaporated portion EP. During this step, additional water W may be supplied in step 146, wherein the additionally supplied water W is mixed with the plant material P and the evaporated portion EP of the subsequent slurry S. The subsequent plant-based slurry S may include water in an amount of at least 75% from the evaporated portion EP. In addition, heat from the evaporated product EP may be used to heat the slurry S. For example, the initial temperature of the evaporated portion EP may be at least 80°C, and the preparation 144 of the subsequent plant-based slurry S may be performed before the amount of heat energy reduction of the evaporated portion EP corresponds to a temperature reduction of more than 30°C. This can be determined using formula (1): Q = m*c*ΔT (Formula 1) in: Q is thermal energy (J) m is mass (kg) c is the specific heat (J / kg / °C), and ΔT is the temperature change (°C).
[0044] In step 150, steps 106 to 144 may be repeated for one or more subsequent slurry mixtures S. The method 100 may be a continuous process that is repeated continuously over a period of time, such as running for 20 hours, where the time from slurry S production to evaporation of product EP may be approximately 3.5 hours.
[0045] From the above it emerges that, although various embodiments of the invention have been described and shown, the invention is not restricted thereto but may also be embodied in other ways within the scope of the subject-matter defined in the following claims.
Claims
1. A method (100) for producing a plant-based concentrated liquid food (FP), the method comprising the following steps: i) preparing (102) a plant-based slurry (S) by mixing at least plant material (P) and water (W); ii) treating (106) the slurry (S) with at least one of an enzyme (E) and heat; iii) separating (110) the slurry (S) into a solid part (SP) and a liquid part (LP); iv) evaporating (116) water from said liquid portion (LP) to produce at least one evaporated portion (EP) comprising evaporated water, and at least one concentrated portion (CP) forming said plant-based concentrated liquid food (FP); v) preparing (144) a subsequent plant-based slurry (S) by mixing at least the plant material (P) and said evaporated portion (EP); and vi) repeating (150) steps ii) to iv) for said subsequent slurry (S).
2. The method according to claim 1, comprising filtering (126) said evaporated portion (EP) with a filter (24) prior to said preparing (144) of said subsequent plant-based slurry (S).
3. The method according to claim 2, comprising cooling (122) said evaporation portion (EP) with a cooler (22) before said filtering (126) of said evaporation portion (EP).
4. Method according to any preceding claim, comprising buffering (130) said evaporated portion (EP) in a tank (26) prior to said preparing (144) of said subsequent plant-based slurry (S).
5. Method according to any preceding claim, comprising heating (134) said evaporation portion (EP) with a heater (30) prior to said preparing (144) of said subsequent plant-based slurry (S).
6. The method according to any preceding claim, wherein the mixing in steps i) and v) is performed in the same mixer (6).
7. Method according to any of the preceding claims, comprising measuring (140) the temperature of the evaporated portion (EP) or of the mixture (EP-W') to which the evaporated portion (EP) belongs before the preparation (144) of the subsequent plant-based slurry (S).
8. Method according to any preceding claim, comprising measuring (142) the amount of said evaporated fraction (EP) prior to said preparing (144) of said subsequent plant-based slurry (S).
9. The method according to any preceding claim, wherein the preparing (144) of the subsequent plant-based slurry (S) comprises supplying (146) water (W) and mixing the supplied water (W) with the plant material (P) and the evaporated fraction (EP).
10. The method according to any of the preceding claims, wherein the subsequent plant-based slurry (S) comprises water of which at least 75% comes from the evaporated fraction (EP).
11. A method according to any preceding claim, wherein the evaporation part (EP) has an initial temperature of at least 80°C and the preparation (144) of the subsequent plant-based slurry (S) is performed before the thermal energy of the evaporation part (EP) is reduced by an amount corresponding to a temperature reduction of more than 30°C.
12. The method according to any preceding claim, wherein the method (100) is a continuous process which is repeated continuously over a period of time.
13. A system (1) for producing a plant-based concentrated liquid food (FP), the system comprising: i) a mixer (6) configured to prepare a plant-based slurry (S) by mixing at least plant material (P) and water (W); ii) a container (10) which enables the slurry (S) to be treated with at least one of an enzyme (E) and heat; iii) a separation unit (12) configured to separate the slurry (S) into a solid part (SP) and a liquid part (LP); iv) an evaporator (18) configured to evaporate water from said liquid portion (LP) to produce at least one evaporated portion (EP) comprising evaporated water, and at least one concentrated portion (CP) forming said plant-based concentrated liquid food (FP); v) a return conduit (20) configured to convey the evaporated portion (EP) from the evaporator (18) to the mixer (6) or a further mixer (6'), the further mixer being configured to prepare a subsequent plant-based slurry (S) by mixing at least plant material (P) and the evaporated portion (EP).
14. The system according to claim 13, wherein the return pipe (20) comprises a temperature sensor (34) configured to measure the temperature of the evaporation portion (EP) or the temperature of the mixture (EP-W') to which the evaporation portion (EP) belongs.
15. System according to claim 13 or 14, wherein the return pipe (20) comprises a flow meter (32) configured to measure the amount of the evaporated portion (EP) or to measure the amount of the mixture (EP-W') to which the evaporated portion (EP) belongs.