Whey end product, method and system for producing a whey end product, and stirring vessel for filling a whey end product

Abstract

The invention relates to a method for producing a gelled whey end product. The method comprises the following steps: producing a whey protein concentrate from whey, with the absolute protein content of the whey protein concentrate being set; performing a microparticulation treatment; transferring the hot whey protein concentrate into a storage vessel having a stirring mechanism; and continuously stirring the hot whey protein concentrate and keeping it hot in the storage vessel; filling hot whey protein concentrate from the storage vessel into an end vessel; and cooling the whey protein concentrate in the end vessel to form a gelled whey end product.

Description

[0001] - 1 - TITLE OF THE INVENTION Whey end product, method and plant for producing a whey end product and agitator vessel for filling a whey end product TECHNICAL FIELD OF THE INVENTION The present invention relates to a method for producing a whey end product from whey. It also relates to a plant for producing a whey end product and, in particular, to agitator vessel for filling a whey end product. BACKGROUND OF THE INVENTION Whey is a by-product of cheese production. It is known from the prior art to further process the resulting whey, since whey proteins in particular are easily absorbed by the human body. Whey is therefore also considered to be nutritionally valuable. For example, the processing of whey into protein powder is known, which is used primarily as a dietary supplement in weight training.Also known is the use of the water-soluble parts of whey as milk serum drinks or the processing of whey into a fat substitute, in which the protein content in the whey is concentrated and processed into inert protein aggregates the size of fat globules. These can mimic the mouthfeel of actual fat in a food. However, whey proteins, which are nutritionally valuable in particular, are currently used primarily in highly processed form in the food industry, among other reasons because their processing is difficult due to their high heat sensitivity. P219991_final - 2 - SUMMARY OF THE INVENTION It is an object of the present invention to provide an alternative process by which whey proteins, which are nutritionally valuable for the human body, can be provided as an alternative food.This object is achieved by a process for producing a gelled whey end product, comprising the following steps: Providing whey. A whey protein concentrate is then produced from the provided whey. The resulting whey protein concentrate has an absolute protein content ranging from 7% to 27% by weight of the whey protein concentrate (g protein / 100 g whey protein concentrate). The appropriately adjusted whey protein concentrate is subjected to a microparticulation treatment. In such a microparticulation treatment, the adjusted whey protein concentrate is subjected to a combined heat and shear treatment. In the present process, the temperature is continuously maintained at a high level, i.e., not only during but also between different sub-steps.The microparticulation of the whey protein concentrate comprises the following steps: Carrying out a first combined shear and heat treatment. The first combined shear and heat treatment is carried out at a first microparticulation temperature in a temperature range of 60°C to 95°C under continuous shearing. P219991_final - 3 - After the first shear and heat treatment, the whey protein concentrate is held hot at the holding temperature in a range of 60°C to 95°C and for a holding time of 10 seconds to 400 seconds. Following the holding, a second combined shear and heat treatment is carried out. This is carried out at a second microparticulation temperature of 60°C to 95°C under continuous shearing.Following the combined shear and heat treatment, the inventive method comprises the following steps: Transferring the hot whey protein concentrate from the microparticulation treatment into a receiving vessel equipped with a stirrer. In the receiving vessel, the still-hot whey protein concentrate is continuously stirred and kept hot. Finally, the still-hot whey protein concentrate is transferred from the receiving vessel into a final vessel. There, the whey protein concentrate is allowed to cool, where it gels into a final whey product. In the context of the present invention, whey is understood to be an aqueous residual liquid produced during cheese production. Depending on the type of cheese production, a distinction is made between sweet whey and sour whey. Sweet whey (also called rennet whey) is produced when milk is thickened with rennet for cheese production or when whey is separated from the milk by microfiltration.Sour whey is produced when milk is broken down by lactic acid bacteria. The whey provided for the process described here can be sweet whey or sour whey. Due to its easier processing, sweet whey can be used in particular in the process according to the invention. P219991_final - 4 - It can be provided that, before concentration, the provided whey is subjected to a preliminary dedusting, defatting and / or pasteurization. Such processes are known per se from the prior art and are therefore not explained further here. It can further be provided that the provided whey is the direct product from cheese production. Alternatively, it can be provided, for example, that a reconstituted whey powder is used for the process. The whey is preferably liquid when it is subjected to the concentration step.In connection with the present invention, it has surprisingly been shown that by exploiting the gel-forming properties of whey proteins, a minimally processed end product can be produced that contains a high proportion of nutritionally valuable whey proteins while exhibiting a consistency equivalent to that of conventional, set yogurts. The present invention specifically utilizes the natural cross-linking property (gelling ability) of heated whey proteins and, according to the invention, maintains this property until the whey end product is filled into the final container. Gelation in the immediate, ready-to-consume end product is only permitted or no longer prevented in the final container.It has been shown that to achieve a suitable degree of gel formation and thus to achieve the desired consistency and firmness of the final product for consumption, the absolute protein content in the whey protein concentrate should be within a defined range. According to the invention, the absolute protein content in the whey protein concentrate is in a range from 7% by weight to 27% by weight. P219991_final - 5 - It has been shown that with a higher absolute protein content used (i.e., higher than 27% by weight), the time of gelation is difficult or impossible to control, so that the whey protein concentrate gels prematurely—i.e., before filling. The upper limit of the protein content used can be technically determined by the type of filtration system.It has also been shown that at a lower protein content (i.e., less than 7 wt%, without the addition of thickeners), the whey protein concentrate gels almost completely or insufficiently to achieve the desired consistency of the final whey product. Gelation induced during production with subsequent liquefaction is not desirable according to the present invention, since permitted "post-gelation" no longer leads to the desired consistency of the final product. In the context of the present invention, the absolute protein content of the whey protein concentrate is understood to mean the protein content in the aqueous whey protein concentrate solution. The absolute protein content of the whey protein concentrate is expressed as a percentage by weight (g protein per 100 g whey protein concentrate = g / 100 g).The absolute protein content in the whey or whey protein concentrate solution is determined by the proportion of dry matter in the solution and the proportion of protein in the dry matter. In the context of the present invention, dry matter (or dry substance) is understood to be the component of an aqueous solution that remains after deduction of the water contained therein. Dry matter content and water content therefore add up to 100%. In the context of the present invention, the dry matter content (DM content) indicates the amount of dry matter in percent by weight (g per 100 g of total substance, for example whey or whey protein concentrate). P219991_final - 6 - In the context of the present invention, the protein content in dry matter (also called relative protein content) is understood to be the mass fraction of protein in the dry matter of the respective substance to be examined.In the context of the present invention, the protein content in dry matter is given in weight percent (g protein per 100 g dry matter = g / 100g). The substance to be analyzed can be, for example, the original whey or the whey protein concentrate. The natural dry matter content of, for example, a sweet whey is approximately 6 wt%, while the protein content in a sweet whey is approximately 0.8 wt%. To produce a whey end product according to the invention, a prepared whey is therefore concentrated and, in addition, specifically adjusted according to the invention with regard to the absolute protein content. The production of a whey protein concentrate from a whey is known per se from the prior art. By concentrating, an increase in the protein content in the dry matter and an increase in the dry matter content in the whey is achieved.The microparticulateation of concentrated whey is also known, although in the prior art the microparticulate is strongly cooled and sheared after a combined heat and shear treatment in order to achieve inerting of the protein particles and thus prevent the formation of a gel by the whey proteins. The production of a whey protein concentrate can, for example, be carried out by means of a filtration step, for example ultrafiltration. In this process, proteins and larger molecules (e.g., bacteria, fat) are primarily retained from the water. P219991_final - 7 - If one filtration step is not sufficient to achieve the desired protein content in the whey protein concentrate, it can be provided to achieve further concentration in one or more additional filtration steps. For example, other components, e.g.water-soluble components of the whey such as sugar or minerals are removed, for example by dilution using diafiltration. By choosing the appropriate filtration process, both the protein content in the dry matter and a concentration of the dry matter in the resulting liquid whey protein concentrate can be achieved. A whey protein concentrate is named according to its protein content in the dry matter. For example, a WPC 60 describes a whey protein concentrate with a protein content in the dry matter of 60 wt%. WPC stands for whey protein concentrate. The following code, e.g. 35, 60 or 80 indicates the wt% in g per 100 g of dry matter. If the produced concentrate has a protein content in the dry matter of more than 90 wt%, for example 95 wt%, such a whey protein concentrate is called WPI (whey protein isolate).The production of a whey protein concentrate can, as indicated, be a single- or multi-stage process. In a multi-stage process, the provided whey, in particular the whey proteins, are concentrated step by step. This can take place in a single, multi-stage filtration system or in two independent filtration systems. Depending on the desired protein content, this may involve, for example, one (or more) ultrafiltration steps and / or one (or more) diafiltration steps, or other purification processes suitable for the desired concentration. P219991_final - 8 - For example, a sweet whey can be concentrated using two ultrafiltration steps connected in series, first to a WPC 35 and then from WPC 35 to WPC 80.If the provided whey has a naturally higher protein content in the dry matter and / or a naturally higher dry matter content, the whey protein concentrate can alternatively be concentrated to a WPC 60 in a one-step process. The whey protein concentrate with the adjusted protein content is then subjected to a microparticulation treatment. During the microparticulation treatment and in the subsequent process steps up to filling, the temperature is continuously maintained at or above a denaturation temperature. Furthermore, the whey protein concentrate is continuously kept in motion. This ensures that the whey proteins are in a partially denatured state and do not crosslink to form a gel.For the purposes of the present invention, the denaturation temperature is understood to be the temperature at which the denaturation of whey proteins begins. Those skilled in the art assume that the denaturation of whey proteins begins at a temperature of approximately 60°C. The higher the temperature, the greater the denaturation achieved. Accordingly, the denaturation temperature can be at least 55°C, for example at least 60°C. It can be provided that the denaturation temperature is at least 65°C. It can further be provided that the denaturation temperature is in a range from 60 to 95°C; it can be provided that the denaturation temperature is in a range from 65°C to 95°C. It can also be provided to achieve a pasteurization effect by means of the denaturation temperature. In this case, it can be provided that the denaturation temperature is not below 70°C.It can be provided that in this case the denaturation temperature is not below 75°C. It can be provided that the denaturation temperature lies in a range of 65°C to 75°C, for example in a range of 65°C to 70°C. It can be provided that the degree of denaturation can be influenced not only by the temperature but also by the time of temperature exposure: at a lower temperature, the same degree of denaturation can be achieved with a longer temperature exposure compared to a higher temperature with a shorter temperature exposure. The desired gel and / or viscosity properties of the final whey product can then be controlled via the degree of denaturation and the absolute protein content used in the whey protein concentrate.For example, a high protein content can comparatively reduce the temperature and / or the time of exposure to temperature, whereas a lower absolute protein content can still produce a desired gel consistency by increasing the temperature and / or the time of exposure to temperature accordingly. In this case, it can be provided that different temperatures and times are used for different sub-steps in a production process. In addition to the degree of denaturation and / or the temperature and / or the time, it can be provided that the properties of the end whey product can be influenced by the applied scraper speed or the generated shear intensity. It should be noted that the time can be linked to the throughput in the system. It should also be noted that the speed of a scraper can be linked to the throughput in the system.Examples of information regarding the time of temperature exposure and the applied speed of a scraper generally refer to a plant with a throughput of 200 L - 300 L of whey protein concentrate per hour. For plants with a higher throughput, the applied scraper speed may need to be increased, or additional scrapers may need to be used. The microparticulation treatment is carried out in a plant capable of exerting high shear forces and temperatures above the denaturation point of whey proteins. Such a plant is also referred to below as a microparticulation plant. The microparticulation takes place in several sub-steps in which the whey protein concentrate is subjected to a sequence of combined shear and heat treatments.It can be provided that, as part of the microparticulation, the whey protein concentrate is first heated to a preheating temperature before carrying out combined shear and heat treatments. The heating can take place, for example, in a heater, such as a plate heat exchanger, a scraped surface heat exchanger, or a tubular heater. The heating temperature can be in a range from 50°C to 75°C. It can be provided that the heating temperature is lower than the subsequent microparticulation temperatures. For example, the heating temperature can be in a range from 55°C to a maximum of 65°C. The whey protein concentrate, optionally heated to a preheating temperature, is subjected to a first shear and heat treatment at a first microparticulation temperature. For this purpose, the whey protein concentrate can be fed from the heater or a tank via lines to a first scraped surface heat exchanger.P219991_final - 11 - In the first scraped surface heat exchanger, heating to the first microparticulation temperature takes place. The first microparticulation temperature lies in a range from 60 °C to 95 °C. A combined shearing treatment takes place under continuous temperature influence. This can be achieved, for example, by a continuously rotating blade in the first scraped surface heat exchanger. A scraped surface heat exchanger of the ASA type from SPX is suitable, for example. A suitable first microparticulation temperature of 80 °C + / - 1 °C for a WPC 80 is mentioned as an example. Due to the heat influence, the whey proteins are denatured or unfolded. The shearing shears the unfolded proteins into particles of a specific size range. The desired size range can be in a range from 0.5 µm to 50 µm.It can be provided that the degree of denaturation of the whey proteins can be influenced not only by the temperature, but also by the treatment time of the first combined shear and heat treatment. In an exemplary plant with a throughput of 200 L of whey protein concentrate per hour (h), the treatment time can, for example, be in a range of 30 seconds (seconds) to 5 minutes (minutes), with a shorter treatment time being selected at higher temperatures. After the first combined heat and shear treatment, the whey protein concentrate is subjected to a heat-holding phase. This step significantly influences the quality of the final whey product, for example with regard to viscosity and thickening behavior. P219991_final - 12 - The heat-holding temperature is in a range of 60 °C to 95 °C with a heat-holding time of 10 seconds to 400 seconds.Here, too, the holding time must be longer at a lower temperature, while the holding time can be shorter at a higher temperature. Accordingly, the holding temperature can be at least 55 °C, provided the holding time is adjusted accordingly. It can also be adjusted to the throughput of the system used. It can be provided, for example, that the holding takes place in a holding section connecting the first scraped-surface heat exchanger to a subsequent, second scraped-surface heat exchanger for the second combined shear and heat treatment.It can further be provided that a heat holder used does not provide for active heating of the whey protein concentrate, but that the temperature of the whey protein concentrate is determined passively, for example via the length, the cross-section and the flow rate as well as via the temperature of the whey protein concentrate from the first scraped surface heat exchanger immediately upstream of the heat holder. In this case, the heat holding temperature at the beginning of the heat holding section corresponds to the first microparticulation temperature, while the temperature is not further adjusted or controlled over the course of the heat holding section. It can be provided that the dimensioning of the line and / or the throughput ensures that the temperature of the whey protein concentrate drops by a maximum of 10 °C, for example by a maximum of 6 °C, during the heat holding phase. Alternatively, it can be provided that the whey protein concentrate is actively brought to a heat holding temperature by a heating unit.In this case, the holding temperature can be set independently of the microparticulation temperature. P219991_final - 13 - During this holding phase, the whey protein concentrate does not undergo any active shearing, although agitation may be provided. This allows the aggregation of the unfolded whey proteins. For an example whey protein concentrate WPC 80 with a dry matter content of 23 wt% and a fruit preparation content of 15.1% at a capacity of 200 L / h, a suitable holding time of 60 seconds has been found. After holding, the whey protein concentrate, still hot, is subjected to a second combined shear and heat treatment at a second microparticulation temperature under continuous shearing. The second microparticulation temperature lies in a range of 60°C to 95°C.It can be provided that the second microparticulation temperature deviates from the first microparticulation temperature, or that it substantially corresponds to it. It can be provided that the second microparticulation temperature is lower than the first microparticulation temperature. For example, it can be permitted for the whey protein concentrate to experience a temperature loss of several degrees Celsius due to transport in the heat-holding section. In this case, the second microparticulation temperature can be 1°C to 10°C, for example 3°C to 6°C, lower than the first microparticulation temperature. It can be provided that the second microparticulation temperature is so high that the degree of denaturation of the whey proteins continues to increase. Alternatively, it can be provided that the second microparticulation temperature is above the first microparticulation temperature.Alternatively, it can be provided that the second microparticulation temperature essentially corresponds to the heat-holding temperature. P219991_final - 14 - The second combined shear and heat treatment can take place in a second scraped-surface heat exchanger, in which heating to the second microparticulation temperature is carried out in combination with a shear treatment. The treatment time can, as explained above, be selected based on the temperature used and the absolute protein content of the whey protein concentrate used. It can be provided that the treatment time is predetermined by the system. By way of example, a treatment time in a range of 30 seconds to 5 minutes is mentioned. A scraped-surface heat exchanger of the ASA type from SPX is suitable, for example.It is assumed that this second combined shear and heat treatment prevents the formation of larger aggregates of unfolded proteins and that any whey protein aggregates formed by the heat treatment are brought into a desired size range, while the proteins remain in a partially denatured state. This results in a more uniform structure of the final gelled whey product. It is possible to adjust the particle size to a size range of 0.5 µm to 1000 µm, preferably from 0.5 µm to 50 µm, by means of the first and second combined shear treatment. It is possible to adjust the particle size to a size range of 0.5 µm to 20 µm, or from 0.5 µm to 15 µm.After the second combined shear and heat treatment, or after microparticulation, the still-hot, microparticulated whey protein concentrate is transferred to a receiving vessel, which is part of a filling system or itself includes a filling mechanism. In the receiving vessel, the whey protein concentrate is kept hot enough to maintain its temperature at least above a minimum temperature. It may be provided that the temperature of the whey protein concentrate is kept above the denaturation temperature. Furthermore, the whey protein concentrate is continuously stirred in the receiving vessel (therefore, it is also referred to as a stirred vessel below). By keeping it hot above a minimum temperature and continuously stirring, the formation of a gel-like crosslinking of the whey proteins is delayed, so that the time of gelation is specifically controlled to the cooling process in the final vessel.It may be possible to limit the residence time of the whey protein concentrate until filling. This can be provided in particular if the storage vessel itself does not have active heating or temperature control. This results in a maximum storage period during which it is ensured that no gelling of the whey protein concentrate occurs. It may be possible to continuously fill whey protein concentrate into the storage vessel while whey protein concentrate is simultaneously being filled. In this situation, there is a continuous mixing of new, hotter whey protein concentrate with the whey protein concentrate already in the vessel. Depending on the system's performance, the residence time can range from a few seconds to 20 minutes, for example in the range of 1 minute to 15 minutes.It can be provided that the receiving vessel is preheated to a minimum temperature immediately before the hot, microparticulated whey protein concentrate is poured into it. For example, it can be tempered to a denaturing temperature. Alternatively, the receiving vessel can be preheated to a lower temperature than the denaturing temperature. This can be provided in particular when the whey protein concentrate itself has a high temperature and, although it cools in the receiving vessel, does not cool below a temperature at which gelation begins due to its high temperature and an adapted residence time in the receiving vessel. It can also or alternatively be provided that the receiving vessel is actively heatable in order to maintain the desired temperature of the microparticulated whey protein concentrate in the receiving vessel, or to maintain the preheating temperature of the receiving vessel.The storage vessel includes a stirrer for continuous stirring. The more homogeneous and even the stirring, the longer the whey protein concentrate can remain in the storage vessel before it needs to be filled – thus, the longer the gelling ability of the hot whey protein concentrate can be maintained before filling. For example, a volume of 30 liters (L) of whey protein concentrate can be held in a 40-liter storage vessel at a temperature of 70°C for a period of up to 10 minutes before being filled into a final vessel for initial gelling. The still-hot, microparticulate whey protein concentrate is filled from the storage vessel directly into the final vessel, where the whey protein concentrate is stored as the final whey product and prepared for consumption. The whey protein concentrate can cool in this final vessel.As the temperature drops and in the absence of movement, the whey protein concentrate finally gels into the final whey product. For filling, the storage vessel itself can comprise a filling mechanism, e.g. a filling head, or can be fluidly connected to a filling mechanism of a filling system. P219991_final - 17 - Depending on the protein content used and / or the treatment temperature and / or the intensity of stirring and / or treatment time during production, gelation leads to a final whey product which preferably has a consistency comparable to that of set yogurt. It is envisaged that the following consistency categories of the final whey product can be achieved by means of the process according to the invention: 1 barely gelling, liquefies very quickly, even under slight shear (e.g.by simply stirring with a spoon); This consistency can be achieved, for example, by: mixing whey protein concentrate WPC 80 (85 wt%) with a fruit preparation (15 wt%), acidifying; subsequent microparticulation at a capacity of 200 L / h, a first microparticulation temperature of 76 °C, a speed of the first scraped surface heat exchanger of 200 rpm (revolutions per minute), a heat holding time of 60 seconds, and a second microparticulation temperature of 72 °C, a speed of the second scraped surface heat exchanger of 200 rpm, homogenization at 100 bar and subsequent filling.2 comparable to set yogurt, but liquefies after repeated stirring with a spoon; This consistency can be achieved, for example, by: mixing a whey protein concentrate WPC 80 (85 wt%) with a fruit preparation (15 wt%), acidifying; subsequent microparticulation at a capacity of 200 L / h, a first microparticulation temperature of 76 °C, a speed of the first scraped surface heat exchanger of 500 rpm; a heat holding time of 60 seconds, and a second microparticulation temperature P219991_final - 18 - of 72 °C, a speed of the second scraped surface heat exchanger of 500 rpm, homogenization at 100 bar and subsequent filling. 3 slightly more set than category 2, liquefies only with intensive stirring with a spoon (e.g. 15 seconds stirring); melts only slowly at room temperature (e.g.after 1h); This consistency can be achieved, for example, by: mixing a whey protein concentrate WPC 80 (85 wt%) with a fruit preparation (15 wt%), acidifying; subsequent microparticulation at a capacity of 200 L / h, a first microparticulation temperature of 80 °C, a speed of the first scraped surface heat exchanger of 500 rpm, a heat-holding time of 60 seconds, and a second microparticulation temperature of 76 °C, a speed of the second scraped surface heat exchanger of 500 rpm, homogenization at 100 bar and subsequent filling. 4 firm, only slightly elastic, consistency comparable to soft butter (room temperature); retains its shape outside the refrigerator for several hours (e.g. 2h); Visually hardly distinguishable from category 3, breaks down into smaller gel pieces when stirred intensively with a spoon, which are difficult to mix into a homogeneous mass.This consistency can be achieved, for example, by: mixing a whey protein concentrate WPC 80 (85 wt%) with a fruit preparation (15 wt%), acidifying; subsequent microparticulation at a capacity of 200 L / h, a first microparticulation temperature of 80 °C, a speed of the first scraped surface heat exchanger of 700 rpm, a heat-holding time of 60 seconds, a second microparticulation temperature of 76 °C, a speed of the second scraped surface heat exchanger of 700 rpm, homogenization at 100 bar, and subsequent filling. P219991_final - 19 - Based on this classification, a final whey product can be visually and / or sensorially assessed. This assessment is simpler than a rheometric measurement, which cannot be performed on the final product because the whey protein concentrate solidifies immediately once it is in the measuring container.In one embodiment, it is not intended to produce a whey end product with the consistency of a yogurt drink. The present process allows a direct, ready-to-eat, and nutritionally high-quality product to be produced from a whey protein concentrate in a technically feasible manner. The quantities specified for the whey protein concentrate are directly transferable to the end product. The key values ​​are always included in ranges. According to the process described here, the whey product is kept in a gelatinous state until filling. The gelling process is only permitted immediately after filling into the final container by adjusting the heat influence and movement of the whey protein concentrate. Only in the final container does the heat- and shear-treated whey protein concentrate gel, thus transforming into the ready-to-eat whey product.This requires that the manufacturing process be closely linked to the filling process – intermediate storage, for example, in a cooling tank prior to filling, or other cooling of the gelling whey protein concentrate during production is not permitted. It has been shown that if the whey protein concentrate microparticles have already gelled before filling, further gelling can be triggered by reheating and shearing the gelled microparticles. However, the same firmness in the final product cannot be achieved as if the microparticles gelled for the first time in the final product. Therefore, gelling of the microparticles before filling into the final container is undesirable and is deliberately prevented by continuously keeping the microparticles hot and agitated.In one embodiment of the process according to the invention, which can be combined with any embodiment mentioned or to be mentioned, unless contradictory, the whey is sweet whey. The use of sweet whey has the particular advantage that the production of a whey protein concentrate has been proven. In contrast, the production of a whey protein concentrate from acid whey is currently rather energetically inefficient, as it requires additional processing steps such as filtration processes. In one embodiment of the process according to the invention, which can be combined with any embodiment mentioned or to be mentioned, unless contradictory, the whey protein concentrate is produced by means of a process selected from ultrafiltration, diafiltration, microfiltration and ion chromatography, or a combination thereof.Depending on the starting whey and / or the concentration to be achieved, the corresponding process or a corresponding combination thereof can be used. In an embodiment of the process according to the invention, which can be combined with any embodiment mentioned or yet to be mentioned, unless contradictory, the first combined shear and heat treatment is carried out in a first scraped surface heat exchanger at a scraper speed in a range of 100 rpm to 1200 rpm and a mass throughput in a range of 150 L / h P219991_final - 21 - to 600 L / h (rpm = revolutions per minute; L / h = liters per hour). In addition, the second combined shear and heat treatment is carried out in a second scraped surface heat exchanger at a scraper speed in a range of 100 rpm to 1200 rpm and a mass throughput in a range of 150 L / h to 600 L / h.It can be provided that the scraper speed of the first scraped surface heat exchanger and the scraper speed of the second scraped surface heat exchanger are the same for the same throughput. Alternatively, it can be provided that the scraper speed of the first scraped surface heat exchanger differs from the speed of the second scraped surface heat exchanger. By selecting the scraper speed, in addition to the temperature and the specific absolute protein content used (and optionally the relative protein content) of the whey protein concentrate, the consistency of the final whey product can be influenced. The following applies: the higher the scraper speed, the thicker the sample becomes. In one embodiment, it can be provided that the method according to the invention is carried out in a larger plant that can handle, for example, a throughput of up to 3000 L / h.It is within the knowledge of a person skilled in the art to adjust the scraper speed accordingly in the event of changed throughput rates in order to produce the whey end product according to the invention. In an embodiment of the method according to the invention, which can be combined with any embodiment mentioned or to be mentioned, unless contradictory, the first microparticulation temperature is in a range from 69°C to 89°C. P219991_final - 22 - In an embodiment of the method according to the invention, which can be combined with any embodiment mentioned or to be mentioned, unless contradictory, the first microparticulation temperature and / or the second microparticulation temperature and / or the heat-holding temperature differ from one another by a maximum temperature range of 10°C, preferably by a maximum temperature range of 5°C.In an embodiment of the method according to the invention, which can be combined with any embodiment mentioned and yet to be mentioned, unless contradictory, the microparticulation treatment additionally comprises: carrying out a pre-microparticulation, which comprises a combined shear and heat pre-treatment after heating the whey protein concentrate to the denaturation temperature and before carrying out the first combined shear and heat treatment, wherein the pre-microparticulation is carried out at a pre-treatment temperature between 60 °C and 95 °C under continuous shearing. It can be provided that the pre-microparticulation is carried out for a time in a range of 30 seconds to 5 minutes. It can be advantageous to carry out three consecutive combined shear and heat treatments to achieve a uniform consistency of the final whey product.In an embodiment of the method according to the invention, which can be combined with any embodiment mentioned or yet to be mentioned, unless contradictory, the pretreatment temperature deviates - from the heating temperature by a maximum temperature range of 10 °C, preferably by a maximum temperature range of 5 °C, and / or P219991_final - 23 - - from the first microparticulation temperature by a maximum temperature range of 20 °C, preferably by 15 °C. It can be provided that the pretreatment temperature deviates from the heating temperature and / or the first microparticulation temperature, but is at least 60 °C, preferably at least 65 °C. In this way, it can be ensured that the whey proteins are kept in the process of denaturation and unfolding during the microparticulation after heating.The pre-microparticulation is carried out in a separate pre-scraped surface heat exchanger located upstream of the first scraped surface heat exchanger. It can be provided that the pre-microparticulation is carried out at a scraper speed in the range of 100 rpm to 1200 rpm and a flow rate in the range of 150 L / h to 600 L / h. In an embodiment of the method according to the invention, which can be combined with any embodiment mentioned or to be mentioned, unless contradictory, the whey protein concentrate is homogenized after microparticulation and before transfer to the receiving vessel. Homogenization can be carried out between the second combined shear and heat treatment and transfer to a receiving vessel. Here, too, the requirement is that the microparticulated whey protein concentrate is kept above the denaturation temperature.In this way, the whey protein concentrate is kept in a gelatinous state. This means that the microparticulated whey protein concentrate is kept hot. Homogenizing whey protein concentrate microparticulates that are still gelatinous is advantageous in order to postpone the gelation process to the final vessel. A commercially available homogenizer may be used for homogenization. It may also be possible to apply a homogenization pressure in a range from 80 bar to 150 bar or even up to 250 bar. It should be noted that the applied homogenization pressure depends on the homogenizer used. The applied homogenization pressure can therefore be adjusted to the usual level by a specialist.It has been shown that a homogenization step can smooth the microparticulate whey protein concentrate, whereby the protein agglomerates are made more uniform. Any lumps that may have formed in the system can be dissolved. The homogenization step can therefore also be used to control the firmness of the final whey product. A similar effect can be achieved in an embodiment without a homogenization step, for example, by increasing the temperature or shear treatment.In an embodiment of the method according to the invention, which can be combined with any embodiment mentioned or yet to be mentioned, provided that this does not contradict the foregoing, the whey protein concentrate from the microparticulation stage is kept at a temperature in the range from 60°C to 95°C, preferably in the range from 70°C to 85°C, until it is transferred to the receiving vessel, preferably until it is filled. This specification ensures that the whey protein is kept in a gelatinizable state from the microparticulation stage onwards, and that the (first) gelation into the final whey product only occurs upon cooling in the final vessel. P219991_final - 25 - It can be provided that the receiving vessel is a stirred vessel with an agitator. In one embodiment, it can be provided that the cooling of the final whey product in the final vessel is monitored.For example, control can be achieved by setting the appropriate ambient temperature. The final whey product can then cool to ambient temperature without any further measures. For example, the ambient temperature can be set to 6°C or lower. In particular, cooling to 6°C or lower can be provided within 11 hours, for example. This can prevent any spores present from growing in the final whey product.In an embodiment of the process according to the invention, which can be combined with any embodiment mentioned or yet to be mentioned, provided there is no contradiction, the absolute protein content of the whey protein concentrate is adjusted depending on the protein content in the dry matter (g / 100 g dry matter) and the proportion of dry matter in the whey protein concentrate, whereby the protein content in the dry matter is in a range from 60 wt% to 95 wt%. By producing a WPC 60 to WPI whey protein concentrate, the protein content in the dry matter can be increased. During concentration, the proportion of the dry matter itself is also increased. The absolute protein content to be used for the present process is determined in this case by adjusting the protein content in the dry matter and the dry matter content in the whey protein concentrate.P219991_final - 26 - With a very high protein content in the dry matter, the dry matter content in the whey protein concentrate can be correspondingly lower in order to achieve comparable properties in the final whey product. Accordingly, the whey provided must be measured with regard to the protein content in the dry matter as well as the dry matter content in the whey. Based on the specific properties of the provided whey, as well as the optional additives to be used, such as acidulants and flavorings, it can then be determined to what extent the protein content in the dry matter and the dry matter content itself must be increased. It is important to consider the extent to which the additives, such as flavorings, contribute to the dry matter and / or the protein content.The whey protein concentrate is adjusted to ensure the desired absolute protein content in the whey protein concentrate or whey protein concentrate mixture (which is created by adding optional additives) as it is transferred to the microparticulation stage. The whey protein concentrate used in the microparticulation stage can be pure whey protein concentrate or a whey protein concentrate mixture comprising pure whey protein concentrate and other additives such as water, acidifiers, or flavorings. The absolute protein content is present in the whey protein concentrate as it is transferred to the microparticulation stage. This means that any dilution effects caused by additives are taken into account during adjustment. For example, a base (a flavor preparation) consisting of 26.7% by weight of mango puree, 16.4% by weight of passion fruit puree, 0.2% of lemon juice concentrate, 56.2% of granulated sugar and 0.6% passion fruit flavor consists of 15.1 wt% whey protein concentrate with a fat content of 1.7 wt%, a protein content of 19.2 wt%, a dry matter content of 23.6 wt%, and a pH of 6.05. By adding 0.5 wt% lemon juice concentrate, the pH of the mixture can be lowered to 5.1. Typically, additives to flavor preparations have a low or almost no appreciable protein content, but do have an influence on the dry matter. Dilution effects caused by additives can be balanced out, for example, by playing with the temperature and / or shear, and if necessary, in comparison with existing whey protein concentrates. In one embodiment, the dry matter content in the whey protein concentrate can be in a range of 10 wt% to 30 wt%.It is possible for the dry matter content in the whey protein concentrate to be in a range from 15 wt% to 25 wt%, for example in a range from 20 wt% to 24 wt% for a WPC 80. In an embodiment of the process according to the invention, which can be combined with any embodiment mentioned or to be mentioned, unless contradictory, the absolute protein content of the whey protein concentrate is in a range from 10 wt% to 20 wt%, particularly preferably in a range from 16 wt% to 20 wt%. In an embodiment of the process according to the invention, which can be combined with any embodiment mentioned or to be mentioned, unless contradictory, the whey protein concentrate is acidified to a pH between 3 and 6.5 before the microparticulation treatment, wherein the acidification is carried out by adding an acidifying agent.Acidification can further thicken the whey protein concentrate. Acidification can also have a beneficial effect on the flavor of the final whey product. Whey protein concentrate alone can have a slightly alkaline flavor, which is mitigated by acidification. It may be intended to adjust the whey protein concentrate to a pH value between 4.8 and 5.2. The pH value is specified for the whey protein concentrate as it is fed into the microparticulation treatment. The pH value is adjusted accordingly for recipes containing the whey protein concentrate, including, for example, mixtures with flavorings such as fruit puree or similar.In one inventive embodiment of the process, which can be combined with any of the aforementioned and yet-to-be-mentioned embodiments, unless contradictory, the acidifying agent is selected from a group comprising: citric acid, citric acid concentrate, lactic acid, malic acid, phosphoric acid, acetic acid, and nitric acid. In one inventive embodiment of the process, which can be combined with any of the aforementioned and yet-to-be-mentioned embodiments, unless contradictory, the acidifying agent is a microorganism culture, and the acidification comprises incubating the whey protein concentrate with the microorganism culture. A microorganism culture can be a monoculture or a mixed culture. A microorganism culture can be a known yogurt or quark culture. Exemplary microorganisms are lactic acid bacteria, such as Lactobacillus bulgaricus and Streptococcus thermophilus, or mixtures thereof.In an embodiment of the process according to the invention, which can be combined with any of the embodiments mentioned and those to be mentioned, provided P219991_final - 29 - does not contradict this, one or more flavorings are added to the whey protein concentrate prior to microparticulation. Such flavorings are selected from a group comprising: sugar, sweetener, fruit puree, and flavorings. Flavorings can be, for example, sweeteners, sugar or types of sugar such as caramelized sugar syrup, glucose syrup, maltodextrin, honey, agave syrup, and preparations thereof. Flavorings can be flavors, natural flavors, flavoring substances, flavor extracts, artificial flavors, or combinations thereof, for example cocoa powder, chocolate powder, chocolate flavoring, coffee flavoring, or fruit flavoring, e.g. of citrus fruit, stone fruit, exotic fruit; caramel flavoring, coconut flavoring. Sour, spicy, salty, or bitter flavors are also possible.Flavorings can also be used as a concentrate and optionally contain an acid component. The flavoring(s) may be a preservative-free semi-finished product made from various ingredients. The flavoring(s) may be pasteurized beforehand. The whey protein concentrate, together with the optional flavorings and optional acidulants, is subjected to the microparticulation process as a whey protein concentrate mixture. Mixing can take place in a separate mixing tank, which, for example, is directly connected to a preheater of a downstream microparticulation system, or which is initially connected to an intermediate pre-run vessel for the preheater for simplified dosing.The amount of optional flavorings and / or optional acidulants and / or an optional additional fat source added may be limited by the absolute protein content required in the whey protein concentrate subjected to microparticulation. In an embodiment of the process according to the invention, which can be combined with any embodiment mentioned or yet to be mentioned, unless contradictory, the proportion of one or more flavorings in a whey protein concentrate mixture subjected to microparticulation is between 0 wt% and 35 wt%, with the lower limit preferably being 1 wt% and the upper limit preferably being 30 wt%, particularly preferably 20 wt%.These proportions refer to the resulting mixture of whey protein concentrate and flavorings (and optional acidulant, fat source) as it is fed to the microparticulation process. In an embodiment of the process according to the invention, which can be combined with any of the aforementioned and yet-to-be-mentioned embodiments, unless contradictory, the fat content in the whey protein concentrate as it undergoes microparticulation is in a range from 0.7 wt% to 30 wt%. It can be provided that no fat is deliberately added to the whey or to the whey protein concentrate. The natural fat content of whey defatted by centrifugation is approximately 0.1 g per 100 g of whey. The concentration of the whey proteins during the production of the whey protein concentrate also inherently results in a concentration of the fat content.If a higher fat content is desired that cannot be achieved through the concentration process, it can be achieved by adding additional fat. One possible fat source that can be added is cream, for example. P219991_final - 31 - If a lower fat content is desired than that achieved through the whey protein concentration process, it can be planned to separate the fats contained in the whey from the protein fraction, for example by microfiltration, and thus reduce the fat content. In practice, complete defatting is not possible. The limit of 0.1 wt% therefore refers to the lowest fat content in the produced liquid whey protein concentrate that is technically possible, for example by ultrafiltration. Possible fat additives to increase the fat content include cream, vegetable fats, vegetable oils, fat emulsions, or similar.The information regarding the fat content refers to the whey protein concentrate as it is transferred to the microparticulation stage. Therefore, it can be pure whey protein concentrate if the whey is to be processed into the final whey product without additives. If additives are added to the whey protein concentrate as mentioned above, the stated fat content refers to the mixture of the whey protein concentrate with the respective additives used. An advantage of the present invention is that a consumable whey final product is produced that does not require the addition of a thickener. The consistency can be controlled essentially by adjusting the absolute protein content, the heat exposure, and the agitation in a technically feasible manner.In an embodiment of the method according to the invention, which can be combined with any embodiment mentioned or yet to be mentioned, provided they do not contradict each other, one or more of the following parameters P219991_final - 32 - are adjusted in order to produce a whey end product according to one of the previously presented categories 1 to 4: • The absolute protein content in the whey protein concentrate. This lies in a range from 7% to 27% by weight of the whey protein concentrate. It can be provided that the absolute protein content lies in a range from 10% to 20% by weight, for example in a range from 16% to 20% by weight. It has been shown that adjusting the absolute protein content has a significant influence on the consistency or gel formation of the whey end product.It has been shown that a WPC with a higher protein content and dry matter content (i.e. higher absolute protein content) forms a gel at lower temperatures compared to a WPC with a lower protein and dry matter content (i.e. a lower absolute protein content). It has been shown that the effect of the absolute protein content on gel formation dominates over the effect of the protein content in the dry matter. • The dry matter content in the whey protein concentrate. This lies in a range of 10 wt% to 30 wt%, for example in a range of 15 wt% to 25 wt%. It has been shown that the dry matter content influences the initiation of gel formation. For example, it has been shown that if two WPCs have the same absolute protein content, the one with a higher dry matter content thickens sooner as the temperature increases. • The pH value of the whey protein concentrate. Which lies in a range of 3 to 6.5.It has been shown that a lower pH leads to the formation of a gel even at lower temperatures. It can therefore be provided that the gel formation is controlled by means of the pH value. P219991_final - 33 - • The temperatures of the microparticulation, which are in a range of 60 °C to 95 °C, preferably in a range of 60 °C to 89 °C. As mentioned, it has been shown that in whey protein concentrates with a relatively lower absolute protein content, gel formation can be triggered by increasing the temperature, whereas for a whey protein concentrate with a higher protein content and a similar consistency of a whey end product, the temperature (and the time of exposure to the temperature) can be reduced. It can be provided that the temperature is set not only with regard to the gelation of the whey protein concentrate, but also with regard to microbiological effects.A pasteurization effect can be achieved by means of a sufficiently high temperature. In this case, the temperature is at least 70°C, in particular at least 75°C. In one embodiment, it can be provided that, in addition to the absolute protein content and / or the dry matter content, and / or the temperature(s) in the microparticulation and / or the pH value, the gelation can be controlled by means of the speed of the scrapers used in the microparticulation. The previously described ranges are applicable here. It can be provided that, for example, depending on the plant, one or more of these parameters are used to achieve a desired consistency of the final whey product. It should be noted that if, for example, one of these parameters is changed, another parameter may also be adjusted. The relationships are described here. In one embodiment, it can be provided that the whey protein concentrate, for example,is converted into microparticulation in a lactose-free manner by an enzymatic treatment. P219991_final - 34 - One aspect of the invention further relates to a whey end product produced by a process according to one of claims 1 to 16. The whey end product corresponds to one of the previously presented categories 1 to 4. Whey end products from conventional microparticulation treatments are often characterized by a sandy or coating mouthfeel. In contrast, whey end products produced by the process according to the invention are characterized by a softer mouthfeel. Although the particles in a whey end product produced according to the invention are comparatively larger, they are enclosed in a product matrix, so that they are not perceived as disturbing or are perceived to a lesser extent as disturbing.One aspect of the invention relates to a plant for producing a whey end product, for example in an embodiment as described above. Such a plant comprises: - a device for producing a whey protein concentrate; - a microparticulation device; and - a filling device with a stirring vessel for filling the whey end product. The plant further comprises lines that connect the device for producing the whey protein concentrate, the microparticulation device, and the filling device in this order. The plant is characterized in that it is designed to keep a whey protein concentrate at a temperature in a range of 60°C to 95°C during the microparticulation until filling.P219991_final - 35 - It can be provided that the individual elements of the system, for example, with regard to the temperature control, shearing, and transport of the whey or whey protein concentrate, are controlled by means of a controller. It can be provided that the control is provided by a computer. A device for producing a whey protein concentrate can be, for example, an ultrafiltration system, a diafiltration system, a microfiltration system, or a system for performing ion chromatography, or a combination of one or more of such systems. An ultrafiltration system from SPX for the LeanCream process is mentioned as an example. TM. Particularly for the production of whey protein concentrates with higher protein contents in dry matter, it is envisaged to combine ultrafiltration, for example, with diafiltration to achieve further concentration. Accordingly, the device for producing a whey protein concentrate comprises an ultrafiltration system with diafiltration steps, so that the whey is brought to the desired concentration in a - in this case - combined process. A microparticulation device is designed to carry out a microparticulation treatment as described above. Depending on the number and sequence of combined shear and heat treatments, the microparticulation device comprises a corresponding number of heating elements (such as plate or tubular heat exchangers or other heating elements), scraped surface heat exchangers, and heat-holding sections.Optionally, the microparticulation device comprises a system for warming or preheating the whey protein concentrate to the denaturing temperature. It can be provided that this system comprises temperature sensors for determining the temperature of the whey protein concentrate being introduced or passing through, and that the temperature control is controlled by the controller in order to bring the whey protein concentrate to the desired temperature. In particular, the microparticulation device comprises at least two scraped-surface heat exchangers. A first scraped-surface heat exchanger is connected by pipes to the optional preheater such that the warmed whey protein concentrate is transported from the preheater to the scraped-surface heat exchanger without its temperature falling below the denaturing temperature. The previously described first combined shear and heat treatment then takes place in the first scraped-surface heat exchanger.The first scraped surface heat exchanger is connected to the second scraped surface heat exchanger via a heat holder. A scraped surface heat exchanger is known in the art. An exemplary scraped surface heat exchanger that can be used according to the invention is, for example, an ASA (APV Shear Agglomerator) scraped surface heat exchanger from SPX. Such a scraped surface heat exchanger can be used as the first and / or second scraped surface heat exchanger and / or also as a pre-scraped surface heat exchanger. Such a scraped surface heat exchanger comprises a rotatable blade and a heating unit. By rapidly rotating the blade under the influence of heat, the proteins of the whey protein concentrate, which have unfolded under the influence of heat, are sheared. By controlling the shear rate and the influence of heat, the resulting particle size of the agglomerated whey proteins can be controlled. The heat holder can, for example, be a simple heat-holding section.These can be lines designed so that the temperature of the transported whey protein concentrate from the first scraped surface heat exchanger, as mentioned, does not drop by more than, for example, 6°C or below 60°C. This can happen passively by adjusting the length and diameter of the lines to the temperature from the first shear and heat treatment, so that a certain temperature loss is taken into account. However, it can be provided to install an actively heated holding cell in such a passive line so that, for example, the whey protein concentrate is actively heated halfway through the route. The scraped surface heat exchangers used are designed to meet the previously described scraper speeds and temperatures for the respective combined shear and heat treatment.The filling device for filling the final whey product comprises a stirring vessel designed to pre-store the hot, microparticulated whey protein concentrate until filling and to maintain its gelling ability. The stirring vessel can be a previously described storage vessel. The lines connect, in particular, the device for producing the whey protein concentrate, the microparticulate device, and the stirring vessel of the filling system in this order. An important aspect of the present invention is that the microparticulate device and the downstream systems and lines are designed to continuously maintain the temperature of the whey protein concentrate at or above the denaturation temperature.Continuous in this case means that at no point during the production process, and thus during the passage of the whey protein concentrate through the system and its individual components, can the whey protein concentrate cool below the denaturation temperature. The system is designed to actively or passively maintain the desired temperature of the whey protein concentrate. Only after filling into the final container is there no targeted influence on the temperature for keeping it hot; instead, the filled whey protein concentrate is left to cool. Cooling below the denaturation temperature is deliberately prevented until filling. The system is therefore suitable for use in the embodiment described here for producing a whey end product.In an embodiment of the system according to the invention, which can be combined with any embodiment mentioned or yet to be mentioned, provided that this does not contradict the invention, the system additionally comprises a homogenizer arranged between the microparticulation device and the agitator vessel and connected to them via lines. A further aspect of the invention relates to a agitator vessel for a system as described above. The agitator vessel, also called the storage vessel, comprises one or more functionally integrated agitators. It can be provided that the agitator vessel comprises at least two counter-rotating agitators. Each agitator is rotatable about its own axis of rotation. It can be provided that the axes of rotation of the individual agitators are different, or it can be provided that the axes of rotation of the individual agitators are identical. In the latter case, the agitators are rotatable about a common axis of rotation.Thanks to the counter-rotating agitators, the hot, microparticulated whey protein concentrate can be stored for a specific period of time until it is filled into the final vessel and still be kept in a gelatinous state. P219991_final - 39 - In an embodiment of the agitated vessel according to the invention, which can be combined with any of the aforementioned and yet-to-be-mentioned embodiments, unless contradictory, a first agitator is designed as a cup agitator. Furthermore, a second agitator comprises at least one scraper, which is rotatable about the first rotation axis. To prevent incipient gelation, the scraper is integrated into the agitated vessel in such a way that it slides along an inner wall of the agitated vessel during rotation.In one embodiment of the mixing vessel according to the invention, which can be combined with any embodiment mentioned or to be mentioned, unless contradictory, the second agitator comprises two scrapers, which are preferably positioned at opposite positions on the inner wall of the mixing vessel. It is provided that both scrapers are rotatable in the same direction about the first axis of rotation. In one embodiment of the mixing vessel according to the invention, which can be combined with any embodiment mentioned or to be mentioned, unless contradictory, each scraper comprises a plurality of through-openings. It has been shown that the presence of through-openings improves the prevention of gelling of the hot whey protein concentrate in the mixing vessel. For all ranges, the key values ​​mentioned belong to the specified range.P219991_final - 40 - BRIEF DESCRIPTION OF THE FIGURES Embodiments of the present invention are explained in more detail with reference to figures. Figure 1 shows a block diagram with a highly schematic overview of the inventive method; Figure 2 shows a further block diagram with a schematic overview of individual method aspects for producing a whey protein concentrate; Figure 3 shows a block diagram with a schematic overview of individual method aspects for producing a whey end product from a set whey protein concentrate; Figure 4 shows a block diagram with a schematic overview of individual elements of a plant for producing a whey end product; and Figure 5 shows a highly schematic overview of a plant for producing a whey end product with a stirred vessel. DETAILED DESCRIPTION OF THE FIGURES Figure 1 shows a block diagram with a schematic overview of a method according to the invention.Whey is concentrated in a single process step. The goal is to concentrate the whey proteins to achieve a desired absolute protein content of 7% to 27% by weight for use in subsequent process steps. Accordingly, not only are the whey proteins concentrated, but their absolute concentration in the whey protein concentrate is also adjusted so that the desired amount of protein is used for microparticulation even upon addition of an optional acidulant and / or an optional flavoring. P219991_final - 41 - The whey protein concentrate produced and adjusted in this way is then subjected to microparticulation. Microparticulation can include one or more heat and combined shear and heat treatments in which the whey protein concentrate is subjected to strong shearing under continuous heat.This process involves unfolding the whey proteins during the triggered denaturation, aggregating, and breaking down the resulting protein aggregates into a defined particle size. After microparticulation, the whey protein concentrate is continuously kept hot until filling into the final container. The temperature of the microparticulated whey protein concentrate can be maintained at least at the denaturation temperature or higher. Following microparticulation and before filling, the microparticulated whey protein concentrate can optionally be homogenized. This optional homogenization can further smooth the whey protein concentrate, further equalizing the size of the protein agglomerates.Even during optional homogenization, the whey protein concentrate is kept hot, meaning its temperature does not fall below the denaturation temperature. The hot, microparticulated and optionally homogenized whey protein concentrate is transferred to a receiver vessel for filling. It can be stored in the receiver vessel until the actual filling. The requirement is that even during storage, it is ensured that the whey protein concentrate does not cool below the denaturation temperature in the receiver vessel. Furthermore, the still-hot whey protein concentrate is stirred in the receiver vessel. This prevents gelation from occurring in the receiver vessel. Gelation is only permitted when the hot whey protein concentrate is filled, since both the heat and stirring are eliminated in the final vessel. Due to the cooling in the final vessel and the lack of movement, the P219991_final - 42 - whey protein concentrate gels and becomes solid.The gelled whey protein concentrate then forms the ready-to-eat whey product. Depending on the protein content of the final whey product and its temperature during filling, gelation can be completed after approximately 3 to 7 minutes, for example. Whether the whey protein concentrate has been processed into a gelled whey product according to the invention can be determined, as previously presented, based on the sensory consistency categories 1 to 4 of the final product itself, particularly visually and haptically. Rheometric determination of a gel is not practical on the final product itself. It has been shown that the absolute protein content in the whey protein concentrate to be processed has an important influence on the gelation behavior and thus on achieving the desired gelation.The following graph shows measurements of the gelation behavior of various whey protein concentrates with the same dry matter content (19 wt%) but different absolute protein contents (15.5 wt%, 13.7 wt%, 12.6 wt%, and 11.3 wt%). The four different whey protein concentrates were prepared from the same raw material by dilution with pure water to achieve the different absolute protein contents and standardized with respect to their dry matter. The effect of the absolute protein content on the storage modulus G' was measured during continuous heating (approximately 2 °C per minute) from 50 °C to 90 °C. P219991_final 43.

[0002] Fig. 6

[0003] The memory module G ' describes the entire viscoelastic behavior of a

[0004] Sample. In combination with the loss modulus G" it characterizes the rheological

[0005] Properties of a sample. The loss modulus G describes the fluid behavior and was not measured here. The physical unit of the storage modulus G ' is

[0006] Pascal (Pa).

[0007] When considering milk or whey, it is called a gel when the

[0008] Memory module G ' > 1 Pa. In the sense of the present invention, a gel is designed according to the invention (and thus sensorially (haptically and visually) perceptible as a gel and classifiable according to consistency categories) if the

[0009] Memory module G ' ≥ 50 Pa. According to the invention, the whey protein concentrate must therefore be adjusted in such a way that it achieves a Pa ≥ 50.

[0010] The graph shows that with a higher absolute protein content, even at lower

[0011] Temperatures a storage module G ' of 50 Pa is reached.

[0012] It has been shown that temperature in particular is an efficient lever for influencing, for example, the effects on gel formation by additives such as sweeteners or

[0013] REPLACEMENT SHEET (RULE 26) - 44 - fruit preparations and also to influence the degree of gel formation. Figure 2 shows, in a further block diagram, a schematic overview of individual process aspects in the production of a whey protein concentrate. A provided whey is concentrated to a whey protein concentrate using a suitable process. This can, for example, be ultrafiltration in combination with diafiltration, or one or more other concentration processes. During the concentration process, both the proportion of whey proteins in the dry matter and the proportion of dry matter in the whey protein concentrate are increased. For this purpose, the proportion of whey proteins in the dry matter and the proportion of dry matter in the concentrate are controlled and adjusted in order to obtain an absolute protein content in the concentrate in a range of 7 to 27 wt%.The protein concentration can be adjusted, if necessary, taking into account the proportions of an optional acidulant and / or an optional flavoring. The goal is to achieve an absolute protein content of between 7 and 27 g per 100 g of whey protein concentrate used, or, if acidulants and / or flavorings are added to the whey protein concentrate for microparticulation, 7 to 27 g of protein per 100 g of the resulting whey protein concentrate mixture. The whey protein concentrate adjusted in this way or the corresponding whey protein concentrate mixture is then fed into the microparticulation process. Figure 3 shows a block diagram schematically overviewing individual process aspects for the production of the final whey product from an adjusted P219991_final - 45 - whey protein concentrate.The prepared whey protein concentrate (or whey protein concentrate mixture) is first warmed. It is advantageously warmed to a temperature that corresponds to or deviates only slightly from the denaturation temperature. The denaturation temperature is arbitrarily set to 60 °C, as discussed previously. The warming temperature ideally lies within a temperature range of 50 °C to 70 °C, more generally within a temperature range of 50 °C to 95 °C. A suitable warming temperature for a whey protein concentrate WPC 80 with a dry matter content of 23 wt%, acidified to a pH of 5.1, and 15 wt% of a flavoring in the whey protein concentrate mixture can be in the range of 60 °C + / - 3 °C. The warming can be carried out, for example, in a plate heat exchanger, which is considered part of the microparticulation system. After warming up, pre-microparticulation can optionally be carried out.This can be a combined heat and shear treatment, carried out, for example, at a temperature of 65°C. Different temperatures can be selected alternatively as discussed. A suitable scraper speed for the aforementioned WPC 80 can be 500 rpm and an output of 200 L / h. This is followed by an initial microparticulation, in which the now warmed whey protein concentrate or the warmed whey protein concentrate mixture is subjected to a combination of heat and shear. This typically takes place in a first scraped surface heat exchanger, as also mentioned, for example, in Figure 4. A suitable temperature to which the whey protein concentrate mixture mentioned above as an example is heated can be in a range from 75°C to 82°C, specifically, for example, 79°C. A suitable scraper speed here is 500 rpm with an output of 200 L / h.The resulting whey protein concentrate mixture is then transported, for example, via a line to a second scraped-surface heat exchanger at the site of the second microparticulation. The line is designed as a heat-holding section, ensuring that the still-hot whey protein concentrate mixture from the first scraped-surface heat exchanger does not cool below a certain temperature. In this example, the heat-holding section is designed so that the whey protein concentrate mixture from the first microparticulation does not fall below the denaturation temperature. This can be achieved by combining the temperature of the first scraped-surface heat exchanger upstream of the heat-holding section and the throughput (capacity) of whey protein concentrate (mixture) in L / h.For the whey protein concentrate mixture mentioned above as an example, the holding temperature can be 79°C, for example; for a pure whey protein concentrate WPC 80 with 23 wt%, it can be 75°C, for example. With a throughput of, for example, 200 L / h, the holding time can be 60 seconds. In this configuration, the holding time can range from 60 seconds to 120 seconds. With changed throughput and / or temperature, the holding time can range from a few seconds, for example, 10 seconds, to 400 seconds or more. The whey protein concentrate (mixture) is transported via the holding section to the second scraped surface heat exchanger and subjected to a second microparticulation. This means that in this second scraped surface heat exchanger, the temperature of the whey protein concentrate (mixture) is also kept above the denaturation temperature, and the liquid is subjected to a shearing treatment.As a result, the whey protein concentrate (mixture) remains liquid and capable of gelling. This second microparticulation can be particularly advantageous if large aggregates have formed after protein denaturation in the first scraped-surface heat exchanger and the aggregation of the unfolded proteins in the heat-holding section. This second microparticulation can achieve more uniform protein aggregates in terms of size in the liquid. P219991_final - 47 - For the whey protein concentrate mixture mentioned above as an example, a suitable microparticulation temperature can be 75°C at a speed of 500 rpm and a throughput of 200 L / h. Regarding the gelation to be achieved, the faster the scraper rotates, the thicker the whey protein concentrate becomes and the greater the degree of gelation in the final whey product.The slower the scraper rotates, the later gelation begins and the lower the degree of gelation achieved in the final whey product. Temperature also has an influence: the higher the temperature, the higher the degree of gelation achieved in the final whey product, and the lower the temperature, the lower the degree of gelation achieved. For example, a lower temperature can be compensated for by a longer treatment time and vice versa. Overall, however, the temperature is limited to a lower limit in order to meet microbiological requirements, for example. For example, pasteurization immediately before filling is not necessary because the treatment temperature is high (above the denaturation temperature) throughout the entire process from microparticle formation onwards, thus creating an inherent pasteurization effect.Finally, the absolute amount of protein used also influences the degree of gelation achieved in the final whey product: the more protein used, the thicker the whey protein concentrate and the higher the degree of gelation achieved. Conversely, the less protein used, the lower the degree of gelation in the final whey product. Through the interaction of the protein content used, the selected temperature, and the scraper speed, the degree of gelation of the final whey product and thus its consistency (e.g., in terms of firmness, liquefaction) can be specifically influenced. P219991_final - 48 - Accordingly, the consistency of the final whey product can be influenced simply by adjusting these parameters during production, and the addition of thickeners, for example, can be dispensed with.After the second microparticulation, the microparticulated whey protein concentrate (mixture) can optionally be homogenized. This homogenization can have an additional effect on the firmness of the final whey product. For example, applying a homogenization pressure has been shown to smooth the final whey product. A lower homogenization pressure leads to less gelation, while a higher homogenization pressure leads to a stronger gelation. A lower homogenization pressure is defined as 50 bar. Good gelation has been achieved at higher homogenization pressures of up to 250 bar, although the homogenization pressure can also be determined, for example, by the homogenizer used.After the second microparticulation or after the optional homogenization, the microparticulated whey protein concentrate (mixture) is transferred to a storage vessel without cooling the whey protein concentrate below the denaturation temperature. Instead, the temperature of the whey protein concentrate is maintained at least at or above the denaturation temperature. The storage vessel can be part of a filling system and includes an agitator. The agitator is necessary to prevent gelling of the hot whey protein concentrate in the storage vessel before filling. It has been found that the better the agitation, the longer the hot whey protein concentrate can be stored in the storage vessel. The use of a double, counter-rotating agitator has proven particularly advantageous. The storage vessel does not need to be actively heated.It can be preheated before the first whey protein concentrate is added, while it experiences inherent temperature control when liquid is continuously removed during filling, but hot liquid from microparticulation or homogenization flows back in. The still-hot whey protein concentrate (mixture) is then filled from the receiving vessel into a final vessel. It then cools in the final vessel without further stirring. This allows the whey protein aggregates to gel. For example, complete gelation to form the final whey product was observed within 5 minutes for the above-mentioned recipe. Table 1 shows example recipes based on a WPC 80 with various absolute protein contents in wt% (Prot. abs.), different fat contents (F) in g, different dry matter contents in wt% (TS), different flavor preparations in wt% (GS), at different acidifications and pH values ​​(final mixture) and different settings, particularly in the microparticulation, such as warming temperature in °C (AW), speed of the scrapers used (DZ-S) in rpm in the pre-microparticulation (VMP), first microparticulation (1st MP), second microparticulation (2nd MP), as well as the respective temperatures of the VMP, 1st MP, and 2nd MP in °C, the hot holding time (HHZ) in °C, and an optional homogenization (HOM) in bar. In addition, the gel consistency achieved for the individual examples of the final whey product is shown in accordance with the previously mentioned consistency categories (KK). A system with a capacity of 200 L / h was used. P219991_final.

[0014]

[0015] - 52 - Table 1 shows the categorization according to the consistency categories introduced here. Consistency categories 1 to 4 correspond to whey end products according to the invention. Consistency category 0 designates a whey end product that is liquid, comparable to a yogurt drink. This category corresponds to an end product from a non-inventive production process. Figure 4 shows, in a highly schematic block diagram, the various individual steps in an exemplary plant for producing a whey end product from a provided whey. The various plant elements can be seen. The movement of the whey within the plant is represented by continuous-line arrows. In particular, those sections in which the whey protein concentrate is moved hot, i.e. at a higher temperature, e.g., above 60°C, are marked with a double arrow.Similarly, plant elements in which, in particular, the whey protein concentrate or the mixture is processed at high temperatures are represented by a double frame. Hot preferably means above 60°C, for example, above 65°C. Hot or keeping hot can be active or passive. With active heating or keeping hot, heat is actively supplied to the whey protein concentrate from the outside, for example, via heating elements. Passive keeping hot means that measures have been taken to ensure that an already hot whey protein concentrate releases as little heat as possible to the environment during movement within the plant or processing in a plant element, or at least does not cool below a certain temperature. An active cooling step of the whey protein concentrate is excluded in the context of the present invention. Cooling is only permitted after filling into the final container, which then leads to the final product.P219991_final - 53 - Whey can be provided in a whey tank for the process according to the invention. It is fed via lines into a plant for producing a whey protein concentrate. Depending on the desired degree of concentration, this can comprise an ultrafiltration plant, diafiltration plant, or similar, or a combination of such plants, as previously mentioned. The produced whey protein concentrate can then be transferred to a mixing tank, in which it can also be stored. Optional acidification and optional mixing with one or more flavorings, if desired, then take place in the mixing tank. If the whey protein concentrate is to be acidified and flavorings added, if desired, this is done in mutual coordination with the desired concentration and the absolute protein content to be used in the whey protein concentrate or the resulting whey protein concentrate mixture.This is indicated by the curved, dashed arrows. The whey protein concentrate or the whey protein concentrate mixture is transferred from the mixing tank to a microparticulation system. In the following, the term "whey protein concentrate" is used in particular, even if it is present in a mixture with an acidulant and / or one or more flavorings. The microparticulation system comprises at least one heater, two or optionally three scraped-surface heat exchangers, and a heat-holding section that fluidically connects the two scraped-surface heat exchangers. The heater can, for example, be a plate heat exchanger, with which the whey protein concentrate is heated to the warming temperature. From this point on, the whey protein concentrate is actively or passively held at at least the warming temperature, preferably at least the denaturation temperature, as indicated by the double frame and the double arrows.In contrast to the state of the art, the whey protein concentrate is not cooled after microparticulation. The previously described warming, combined shear and heat treatments, and intermediate heat holding take place in the microparticulation system. The microparticulation system can be configured to perform two or even three combined shear and heat treatments. If homogenization is planned, the microparticulated whey protein concentrate is transferred hot from the microparticulation system to a suitable homogenizer. A commercially available homogenizer can be used for this purpose, provided a minimum pressure of 50 bar, preferably 100 bar, can be applied. The optional homogenization takes place while the whey protein concentrate is still hot, and the system is designed so that the whey protein concentrate continues to be hot when it leaves the homogenizer and is fed into the filling system.The filling system comprises at least one feed vessel with an agitator. It is particularly advantageous if the agitator is designed as a double agitator, with the agitators rotating in opposite directions to each other. It has been found that such a double agitator can successfully prevent premature gelling of the hot whey protein concentrate in the feed vessel. This is particularly successfully prevented if one of the agitators scrapes along the inside of the feed vessel. A double scraper can be provided as previously described. Such scrapers have an additional beneficial effect if they themselves have a plurality of flow-through holes, with which an additional flow effect can be achieved. Such holes can be provided on one or both scrapers over the entire height of the feed vessel.P219991_final - 55 - An additional flow effect is particularly advantageous when the whey protein concentrate used has a relatively high absolute protein content, and, in addition, a higher temperature is required to produce strong gelation in the whey end product. Figure 5 shows a highly schematic overview of a system 1 for producing a whey end product 12 with a stirring vessel 4. A controller 10, the device 2 for producing a whey protein concentrate, the device 3 for microparticulation, and the lines 5 are shown highly schematically, while the stirring vessel 4 is shown in more detail. The stirring vessel 4 is designed to prevent gelation before filling into the final vessel 11.This can be achieved by means of agitator 6 and by adjusting the flow rate to keep the residence time in the agitated vessel short (so that the temperature of the whey protein concentrate in the agitated vessel does not drop too much). In particular, the two different agitators 6 can be seen, whose respective rotation axes 8 are identical (see dot-dashed line). The agitator 6, located centrally in the agitated vessel 4, is designed as a cup agitator. An embodiment with two "cup levels" is shown here. The second agitator comprises two scrapers 15. Preferably, although not shown here, each scraper 15 is adapted to the inner wall of the agitated vessel such that it scrapes along the inner wall of the agitated vessel when it rotates in the agitated vessel 4 by means of a drive 9. The scrapers 15 shown here are designed like blades. It can be provided that the scrapers 15 are spaced apart from the outlet 7 on the inside.The rotation of the agitators 6 in the agitator vessel 4 around the rotation axis 8 mixes the hot, microparticulated whey protein concentrate. It can be provided that the concentrate is circulated in the agitator vessel 4 without drawing in air. For further improvement, through-openings 16 are provided in the two lower blades of the scrapers 15, with which even more uniform mixing of the hot whey protein concentrate in the agitator vessel 4 can be achieved. In combination with the double beaker agitator, an overall uniform mixing of the gelling whey protein concentrate is achieved, so that few or almost no gel lumps can form in the agitator vessel 4 before filling.Once the whey protein concentrate has been poured from the outlet 7 of the agitated vessel 4 into the final vessel 11, movement of the whey protein concentrate is omitted in the final vessel and cooling is permitted. This allows gelling to form the final whey product 12 in the final vessel 11. In the context of the present invention, relative specifications such as high or low protein content, high or low temperature, high or low scraper speed, or the like refer to specifications within the specified, suitable ranges. In the receiving vessel, the whey protein concentrate is further kept at a temperature above the denaturation temperature. As previously mentioned, this can be active or passive heating. Filling then takes place directly into a final vessel. Accordingly, this is referred to as coupled production and filling.Only in the final vessel is the whey protein concentrate allowed to cool, and thus gel into the final product. P219991_final - 57 - List of reference symbols 1 Plant for producing a whey end product 2 Device for producing a whey protein concentrate 3 Device for microparticulation 4 Stirring vessel 5 Lines 6 Stirrer 7 Outlet 8 Rotation axis 9 Stirrer drive 10 Control system 11 Final vessel 12 Whey end product 13 Filling device 14 Homogenizer 15 Through openings P219991_final.

Claims

- 58 - CLAIMS 1. A method for producing a gelled whey end product, comprising the following steps: - producing a whey protein concentrate from a whey, wherein the whey protein concentrate is adjusted to an absolute protein content which is in a range from 7% by weight to 27% by weight of the whey protein concentrate, - carrying out a microparticulation treatment, comprising the following steps: - carrying out a first combined shear and heat treatment at a first microparticulation temperature of 60°C to 95°C with continuous shearing, - keeping the whey protein concentrate from the first shear and heat treatment hot at the hot-hold temperature in a range from 60°C to 95°C and for a hot-hold time of 10 seconds to 400 seconds, - carrying out a second combined shear and heat treatment at a second microparticulation temperature of 60°C to 95°C with continuous shear,and wherein the process is characterized by the following steps: - transferring the hot whey protein concentrate into a receiving vessel with a stirrer, and continuously stirring and keeping the hot whey protein concentrate hot in the receiving vessel; - filling the hot whey protein concentrate from the receiving vessel into a final vessel; and cooling the whey protein concentrate in the final vessel to form a gelled whey product. P219991_final, - 59 - 2. The process according to claim 1, characterized in that the whey is a sweet whey.

3. The process according to any one of the preceding claims, characterized in that the whey protein concentrate is produced by a process selected from ultrafiltration, diafiltration, microfiltration, and ion chromatography, or a combination thereof.

4. The process according to any one of the preceding claims, characterized in that the first combined shear and heat treatment is carried out in a first scraped-surface heat exchanger at a scraper speed in a range of 100 rpm to 1200 rpm and a mass flow rate in a range of 150 L / h to 600 L / h, and that the second combined shear and heat treatment is carried out in a second scraped-surface heat exchanger at a scraper speed in a range of 100 rpm to 1200 rpm and a mass flow rate in a range of 150 L / h to 600 L / h.Method according to one of the preceding claims, characterized in that the first microparticulation temperature is in a range from 69 °C to 89 °C.

6. Method according to one of the preceding claims, characterized in that the first microparticulation temperature and / or the second microparticulation temperature and / or the heat-holding temperature are increased by a P219991_final. - 60 - maximum temperature range of 10°C, preferably by a maximum temperature range of 5°C.

7. The method according to any one of the preceding claims, characterized in that the microparticulation treatment additionally comprises: - performing a pre-microparticulation, which comprises a combined shear and heat pretreatment after heating the whey protein concentrate to the denaturation temperature and before performing the first combined shear and heat treatment, wherein the pre-microparticulation is carried out at a pretreatment temperature between 60°C and 95°C under continuous shear. 8.Process according to claim 7, characterized in that the pretreatment temperature deviates from the denaturation temperature by a maximum temperature range of 10°C, preferably by a maximum temperature range of 5°C, and / or from the first microparticulation temperature by a maximum temperature range of 20°C, preferably by 15°C.

9. Process according to one of the preceding claims, characterized in that the whey protein concentrate is homogenized after microparticulation and before transferring to the receiving vessel.

10. Process according to one of the preceding claims, characterized in that the whey protein concentrate from microparticulation is homogenized up to P219991_final. - 61 - the transfer to the storage vessel, preferably until filling, is maintained at a temperature ranging from 60°C to 95°C.

11. Process according to one of the preceding claims, characterized in that the absolute protein content of the whey protein concentrate is adjusted depending on the protein content in the dry matter (g / 100 g dry matter) and the dry matter content in the whey protein concentrate, wherein the protein content in dry matter is in a range from 60 wt% to 95 wt%.

12. Process according to one of the preceding claims, characterized in that the absolute protein content of the whey protein concentrate is in a range from 10 wt% to 20 wt%, particularly preferably in a range from 16 wt% to 20 wt%.

13. Process according to one of the preceding claims, characterized in that the whey protein concentrate is adjusted to a pH value between 3 and 6 before the microparticulation treatment.5 is acidified, wherein the acidification is effected by adding an acidulant.

14. A method according to any one of the preceding claims, characterized in that one or more flavorings are added to the whey protein concentrate prior to microparticulation, wherein the flavorings are selected from a group comprising: sugar, sweetener, fruit puree, and flavorings. P219991_final. - 62 - 15. The method according to claim 14, characterized in that the proportion of one or more flavoring agents in a whey protein concentrate mixture subjected to microparticulation is between 0 wt% and 35 wt%, with the lower limit preferably being 1 wt% and the upper limit preferably being 30 wt%, particularly preferably 20 wt%. 16.Method according to one of the preceding claims, characterized in that at least the following parameters are adjusted to produce the final whey product: - the absolute protein content in the whey protein concentrate, which is in a range of 7 wt% to 27 wt% of the whey protein concentrate, preferably in a range of 10 wt% to 20 wt%, particularly preferably in a range of 16 wt% to 20 wt%; and / or - the dry matter content in the whey protein concentrate, which is in a range of 10 wt% to 30 wt%, preferably in a range of 15 wt% to 25 wt%; and / or - the pH of the whey protein concentrate, which is in a range between 3 and 6.5, and / or - the microparticulation temperatures, which are in a range from 60°C to 95°C, preferably in a range from 60°C to 89°C, and / or - a shearing treatment, which is in a range from 100 rpm to 1200 rpm at a throughput of 150 L / h to 600 L / h.

17. A whey end product produced by a process according to any one of claims 1 to 16. P219991_final. - 63 - 18. A plant (1) for producing a whey end product (12) according to one of the preceding claims, comprising: - a device (2) for producing a whey protein concentrate; - a microparticulation device (3); and - a filling device (13) with a stirring vessel (4) for filling the whey end product (12), as well as - lines (5) connecting the device (2) for producing the whey protein concentrate, the microparticulation device (3), and the filling device (13) in this order, wherein the plant (1) is characterized in that it is designed to keep a whey protein concentrate at a temperature in a range from 60°C to 95°C during the microparticulation until filling. 19.Plant (1) according to claim 18, characterized in that it additionally comprises a homogenizer (14) which is arranged between the microparticulation device (3) and the filling device (13) and is connected to these via lines (5).

20. Agitator vessel (4) for a plant (1) according to claim 18 or 19, characterized in that it comprises one or more functionally integrated agitators (6), preferably at least two counter-rotating agitators (6) which are rotatable about a common axis of rotation (8).

21. Agitator vessel (4) according to claim 20, characterized in that it comprises two counter-rotating agitators (6), wherein a first agitator (6) is designed as a P219991_final. - 64 - A cup agitator is formed, and wherein a second agitator (6) comprises at least one scraper (15) which is rotatable about the first rotation axis (8), wherein the scraper (15) slides along an inner wall of the agitated vessel (4) during rotation.

22. Agitated vessel (4) according to claim 21, characterized in that it comprises two scrapers (15), which are preferably positioned at opposite positions on the inner wall of the agitated vessel (4).

23. Agitator (4) according to claim 21 or 22, characterized in that each scraper (15) comprises a plurality of through-openings (16). P219991_final

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