Method for producing capsules containing biological cells derived from at least one aquatic organism and capsules obtainable therewith

Abstract

The invention relates to a method for producing capsules containing biological cells derived from at least one aquatic organism, comprising: providing cells derived from aquatic organisms, selected from isolated cells and a cell mass from in vitro cultured cells; providing a carrier substrate solution and a crosslinker solution for the carrier substrate solution for encapsulation of the cells; encapsulating the cells with the carrier substrate solution and the crosslinker solution, wherein the capsules containing the cells are obtained; and removing and optionally washing the capsules. The invention also relates to capsules produced by the method.

Description

[0001] Methods for producing capsules containing biological cells derived from at least one aquatic organism, and capsules obtainable therefrom

[0002] The present invention relates to a method for producing capsules containing biological cells derived from at least one aquatic organism, and to capsules obtained therefrom. In particular, the present invention relates to a method for producing capsules that can be used as synthetic caviar, and to the capsules obtained therefrom.

[0003] The salted roe (eggs) of the sturgeon is called caviar. High-quality caviar has traditionally been obtained by slaughtering sturgeon, as only immature eggs are robust enough to withstand the thorough removal of gonadal tissue and the subsequent salting process. A slightly lower-quality caviar is now produced from stripped sturgeon eggs, thus avoiding the need to kill the fish.

[0004] The still predominant method of harvesting sturgeon roe by killing them is problematic from both an animal welfare and environmental perspective (overfishing). This is compounded by the general scarcity of this product and its associated high price. Furthermore, caviar is relatively perishable. In particular, it undergoes fermentative degradation by enzymes in the tissue and oxidation by atmospheric oxygen (fat oxidation). Contamination of the caviar by bacterial growth or microplastics, which are ubiquitous in the world's oceans, must also be considered under the given circumstances of harvesting.

[0005] Alternatively, the roe of other, more accessible or available fish species, such as lumpfish or salmon, is also used as so-called alternative caviar.

[0006] It is also known to produce synthetic caviar. This process does not use fish roe, but attempts to mimic the appearance, texture, and taste of real caviar. For example, seaweed extracts form the basis for synthetic caviar.

[0007] Compared to conventional and alternative caviar, the production of synthetic caviar offers several advantages: The product's design and properties, for example, can be flexibly adapted with regard to the desired color, shape, or size; the frequently used algae extracts are an inexpensive and readily available raw material; and some products are entirely free of animal components. The prior art includes the following examples of synthetic caviar production. For instance, DE 3432309 Al describes a process for producing granular protein structures with caviar-like sensory properties. This process uses a structuring solution made from stabilized liquid slaughter blood plasma, the protein content of which has been increased to 7.0 to 10.5% by weight, and additives such as...NaCl, thickeners, dyes and preservatives, form coagulated droplets in a heated layer of oil.

[0008] Furthermore, DE 60027757 T2 discloses a method and an apparatus for the production of granular caviar, which essentially comprises the production of a mixture comprising an albumin-containing colloidal solution, water and gelatin, and the processing of the mixture into a granular form.

[0009] Finally, DE 1965743 describes a granular protein foodstuff that imitates the caviar of sturgeon, salmon and other fish species, as well as a process for its production, wherein the process involves the preparation of a solution of protein substances, its mixing with gelatin and the introduction of this mixture into chilled edible oil, wherein the gelatinous granules formed are treated with a NaCl solution of salts of at least divalent metals.

[0010] However, the aforementioned advantages of synthetic caviar are offset by some disadvantages: Synthetic caviar is generally a product with a lower nutritional value compared to real or alternative caviar. For example, the protein content of alternative salmon caviar is 20% by weight, whereas the protein content of synthetic caviar is very low, at only 1 to 2% by weight. Furthermore, real and alternative caviar contain many minerals (e.g., calcium, magnesium, potassium, phosphorus, iron), vitamins A, B, D, and E, and omega-3 fatty acids.

[0011] Finally, synthetic caviar often resembles real caviar in appearance and texture, but differs significantly in its biological composition. This problem is reflected as a structural issue in the development of animal-free substitutes, and especially caviar substitutes based on alternative protein sources.

[0012] Against this background, the object of the present invention is to provide an improved method for producing capsules containing biological cells, in particular a caviar substitute or synthetic caviar that does not require the killing of animals, especially fish roe-producing animals, and yields a product that is adapted to real or alternative caviar with regard to appearance, texture, and ingredients, especially protein content, as well as a product obtainable by the method. This object is achieved according to the invention by the method and the capsules, each with the features of the independent claims.

[0013] The method according to the invention is a method for producing capsules containing biological cells originating from at least one aquatic organism, comprising:

[0014] Providing cells derived from at least one aquatic organism, selected from isolated cells and a cell mass of in-vitro cultured cells;

[0015] Providing a carrier substrate solution and a crosslinking solution for the carrier substrate solution for encapsulating the cells;

[0016] Encapsulation of the cells with the carrier substrate solution and the crosslinking solution, whereby the capsules containing the cells are obtained; and

[0017] Separate and, if necessary, wash the capsules.

[0018] The capsules according to the invention contain biological cells in a hydrogel, wherein the cells originate from at least one aquatic organism, and wherein the capsules are preferably obtainable according to the method according to the invention or one of its embodiments.

[0019] In the present procedure, the at least one aquatic organism is selected, in particular, from fish, molluscs and / or crustaceans, but is not limited to them.

[0020] The fish can be selected, for example, from the sturgeon family (Acipenseridae) and the salmon family. Preferred sturgeon species include, for example, sterlet, Atlantic sturgeon (Acipenser oxyrinchus), Siberian sturgeon, Russian sturgeon, and beluga.

[0021] The cells used in the method according to the invention can be selected without restriction from one or more species of the fish, molluscs and crustaceans mentioned above, such as several species of fish, molluscs or crustaceans, or any mixtures of cells of the aforementioned aquatic organisms, such as mixtures of cells from fish and molluscs, mixtures of cells from molluscs and crustaceans, etc.

[0022] According to the present method, the cells, which originate from aquatic organisms, are provided as isolated cells or as a cell mass of cultured cells. As a first step, isolated cells are obtained by biopsy from the organs of a living or dead animal in a manner known per se.

[0023] The isolated cells can be cultured in a manner known per se to obtain a cell mass of cultured cells as defined in the present invention. Cells originating from aquatic organisms are cultured—depending on the physiological conditions of the donor animal—under conditions of 0 to 5% CO2, preferably 0 to 4% CO2, more preferably 0 to 3% CO2, and particularly 0 to 2% CO2, and at 16 to 25 °C, preferably 16 to 23 °C, more preferably 16 to 22 °C, and particularly 16 to 20 °C. The following culture conditions for fish cells can be used as specific examples:

[0024] • Wood mackerel - TTRsdlx, 20°C, 2% CO2

[0025] • Rainbow trout - OMYIeb6b, 20 °C, 2% CO2

[0026] • Carp - CCAPin2L2K, 25 °C, 0 % CO2

[0027] • Atlantic sturgeon - AOXnie4b, 20°C, 2% CO2

[0028] Suitable cultivation media include, for example, “Dulbecco’s Modified Eagle Medium” (DMEM), “Roswell Park Memorial Institute” (RPMI) 1640 Medium, “Dulbecco’s Modified Eagle Medium Nutrient Mixture” F-12 (DMEM F12) and “Minimum Essential Medium” (MEM), all available from Thermo Fisher Scientific, as well as Hams F-10, F-12 and Medium 199 (M199), available from Sigma-Aldrich.

[0029] Depending on the scale, cultivation can be carried out in common cell culture vessels such as well plates, Erlenmeyer flasks, etc., in incubators, shaking incubators or bioreactors.

[0030] The cell mass obtained through cultivation differs from the originally isolated cells as follows. Passage 0 (the first isolated cells) is more heterogeneous than higher passages obtained during cultivation. In particular, the freshly isolated cells often still exhibit a similar gene expression profile to their donor tissue. However, cells cultured for longer periods often differentiate into a kind of precursor or stem cell stage. This is also a way to analytically distinguish the (freshly) isolated cells used in the present invention from the cell mass used in the present invention.

[0031] The aforementioned cell mass can be used either as such (i.e., the living cells of the cell mass) or, after cell inactivation, for encapsulation. Inactivation can be achieved, for example, by freeze-drying, removal of the nutrient solution, or storage at low temperatures, e.g., in a freezer at -20°C, yielding, depending on the inactivation method, a so-called cell meal or fresh mass. Therefore, in this application, the term "cell mass" encompasses both living and dead cells. According to a preferred embodiment of the present invention, the carrier substrate solution is a solution based on alginate, collagen, fibrin, dextran, chitosan, cellulose, hyaluronic acid, etc., which is suitable for the production of a hydrogel, preferably alginate, more preferably sodium alginate.The carrier substrate solution typically has a concentration of 0.5 wt% to 10 wt%, preferably 1 wt% to 5 wt%, and particularly 2 wt% to 3 wt%. The amount of carrier substrate solution required, for example, to produce 1000 capsules, is approximately 6 to 15 ml, preferably 8 to 13 ml and 9 to 11 ml, depending on the size of the capsules to be produced. 0.5 million to 1.5 billion cells / ml, preferably 100 million to 1 billion, and particularly 300 to 800 million cells / ml, are added to the carrier substrate solution to achieve a protein content of 10–25%.

[0032] The crosslinking solution is a solution that transforms the liquid carrier substrate solution into a solid hydrogel material. Depending on the carrier substrate solution, this can occur via a physical or chemical process. An example of a chemical process is the reaction of a PEG-thiol crosslinking solution and maleimide-functionalized dextran (e.g., available as a hydrogel kit, "3-D Life Dextran-PEG Hydrogel FG" from Cellendes GmbH). An example of a physical process is the ionic crosslinking of alginate by multivalent cations. According to a preferred embodiment of the present invention, the crosslinking solution is a solution of Ca 2+ , Ba 2+ , Cu 2+ , Sr 2+ , Zn 2+ , Fe 2+ , Mn 2 *, Al 3+ or Fe 3+ , preferably a solution containing divalent cations such as Cu 2+ , Zn 2+ , Fe 2+ or Ca 2+contains, more preferably a Ca 2+ -containing solution, such as a calcium chloride solution. The crosslinking agent solution typically has a concentration of 1 mM to 10 M, preferably 5 mM to 1 M, and particularly 10 mM to 100 mM.

[0033] According to a preferred embodiment of the present invention, the capsules are full capsules and the encapsulation step comprises:

[0034] Adding the cells to the carrier substrate solution, thereby obtaining a suspension; dropping the resulting suspension into the crosslinking solution, thereby obtaining full capsules containing the cells; and

[0035] Separate and, if necessary, wash the full capsules.

[0036] The suspension can be introduced into the crosslinking solution in a manner known per se, e.g. by means of a liquid line, in particular a pipe or hose (inner diameter e.g. 0.8 to 1.7 mm, preferably 0.9 to 1.6 mm, in particular 1.0 to 1.5 mm, optionally provided at the end with a cannula, e.g. an injection cannula, which may have an inner diameter of e.g. 0.5 to 1.5 mm, preferably 0.6 to 1.3 mm and in particular 0.8 to 1.1 mm), which is connected to a pump, e.g. a peristaltic pump, with a suitable delivery rate (e.g. 0.2 to 1.0 ml / minute, preferably 0.4 to 0.8 ml / minute and in particular 0.5 to 0.7 ml / minute). The outlet opening of the liquid line (optionally of the cannula attached to the end of the tube) is located, in particular, vertically 5 to 15 cm, preferably 7 to 12 cm and especially preferably 8 to 11 cm above the carrier substrate solution in a vessel.Finally, the shape of the capsules can be adjusted by agitating the crosslinking solution (i.e., deviating from the essentially spherical shape obtained without further measures), whereby, for example, an elongated distortion of the capsules can be achieved by swirling the crosslinking solution. Furthermore, the diameter and shape of the capsules can be adjusted by modifying the size (via the flow rate and / or the diameter of the outlet opening of the tubing (optionally the injection cannula)) and the drop height of the suspension drops during injection. Capsule diameters in the range of 1 to 7.5 mm, preferably 1.5 to 6 mm, and particularly 3 to 5 mm, can be achieved. The residence time of the formed capsules in the crosslinking solution is 2 to 50 minutes, preferably 5 to 40 minutes, and particularly 10 to 30 minutes.

[0037] According to a preferred embodiment of the present invention, the capsules are hollow capsules and the encapsulation step comprises:

[0038] Adding the cells to the crosslinking solution to obtain a suspension;

[0039] Dropwise introduction of the obtained suspension into the carrier substrate solution, resulting in hollow capsules containing the cells; and

[0040] Separation and, if necessary, washing of the hollow capsules.

[0041] Regarding the formation of hollow capsules according to the method of the present invention, the parameters specified above for the formation of solid capsules apply analogously, with the exception that, for the formation of hollow capsules, a cell-containing crosslinking solution is dripped into the carrier substrate solution.

[0042] According to a preferred embodiment of the present invention, in the case of solid capsules, the provided carrier substrate solution and in the case of hollow capsules, the provided crosslinking solution contain additives selected from, but not limited to, one or more of colorants, flavorings, spices, vitamins and minerals. The colorants are food colorings approved in the EU (Regulation (EC) No. 1333 / 2008), preferably caramel (E 150a - black), vegetable carbon (E 153 - black), quinoline yellow (E 104 - yellow), riboflavins (E 101 - yellow), lutein (E 161b - orange-yellow), lithol ruby ​​BK (E 180 - red), carmine (E 120 - red), copper complexes of chlorophylls and chlorophyllins (E 141 - green), erythrosine (E 127 - pink), in particular caramel (E 150a - black), carotenoids (E 160a - orange), anthocyanins (E 163 - purple), betanin (E 162 - red), carmine (E 120 - red), paprika extract (E 160c - orange-red).Curcumin (E 100 - yellow). Usable flavorings are flavorings approved in the EU according to Regulation (EC) No. 1334 / 2008, preferably natural and nature-identical flavorings, in particular those that produce a fish flavor, such as 3-methylbutanal, hexanal, (Z)-hept-4-enal, n-octanal, trans-2-octenal, trans-2-nonenal, decanal, hepta-(2E,4E)-dienal, trimethylamine, 2-hexenal, 3-methylnona-2,4-dione, methylsulfinylmethane, 2-ethylhexan-l-ol, 2-pentylfuran, 2-methylpyridine. Spices that can be used include salt, pepper, garlic, coriander, turmeric, thyme, rosemary, cinnamon, anise, fennel, chili, cloves, preferably salt, pepper, garlic, ginger, coriander, chili, and especially salt, pepper, ginger, and garlic. Usable vitamins are those approved in the EU according to Regulation (EC) No. 1925 / 2006, preferably vitamin A, vitamin D, vitamin E, vitamin K, vitamin B1, vitamin B2, niacin, pantothenic acid, vitamin B6, folic acid, vitamin B12, biotin, and vitamin C, especially vitamin D.Vitamin C, vitamin B6, vitamin B12 and folic acid. Minerals that are approved in the EU according to Regulation (EC) No. 1 may be used. 1925 / 2006 are, for example, calcium chloride, calcium salts of citric acid, calcium gluconate, calcium glycerophosphate, calcium lactate, magnesium acetate, magnesium carbonate, magnesium chloride, magnesium salts of citric acid, magnesium gluconate, magnesium glycerophosphate, magnesium salts of orthophosphoric acid, magnesium lactate, iron carbonate, iron citrate, iron ammonium citrate, iron gluconate, iron fumarate, iron sodium diphosphate, iron lactate, iron sulfate, elemental iron, copper carbonate, copper citrate, copper gluconate, copper sulfate, copper lysine complex, sodium iodide, sodium iodate, potassium iodide, potassium iodate, zinc acetate, zinc chloride, zinc citrate, zinc gluconate, zinc lactate, zinc oxide, zinc carbonate, zinc sulfate, manganese carbonate, manganese chloride, manganese citrate, manganese gluconate, manganese glycerophosphate, manganese sulfate, sodium hydrogen carbonate.Sodium carbonate, sodium citrate, sodium gluconate, sodium lactate, sodium hydroxide, sodium salts of orthophosphoric acid, sodium selenate, sodium hydrogen selenite, sodium selenite, sodium fluoride, potassium fluoride, potassium hydrogen carbonate, potassium carbonate, potassium chloride, potassium citrate, potassium gluconate, potassium glycerophosphate, potassium lactate, preferably calcium chloride, calcium gluconate, magnesium acetate, magnesium chloride, magnesium gluconate, iron carbonate, iron citrate, iron ammonium citrate, elemental iron, copper citrate, copper gluconate, copper sulfate, sodium iodide, potassium iodide, zinc acetate, zinc citrate, zinc gluconate, manganese carbonate, sodium citrate, sodium gluconate, sodium lactate, sodium selenite, sodium fluoride, potassium fluoride, potassium citrate, in particular calcium chloride, magnesium acetate, iron citrate, copper gluconate, potassium iodide, zinc acetate, manganese carbonate, sodium selenite and potassium fluoride.

[0043] According to a preferred embodiment of the present invention, the capsules obtained are transferred to a brine solution after separation. The brine solution has a salt content of 1 to 10 wt%, preferably 2 to 5 wt% and particularly 2.8 to 3.5 wt%.

[0044] Finally, one embodiment of the present invention also relates to the capsules obtainable according to the inventive method as described above. Depending on their taste and texture properties, the capsules obtained can be used as a general protein-rich food (supplement) or, if the cells encapsulated are those of sturgeon or salmonids, as artificial caviar. Further details and advantages of the present invention will become apparent from the following description of preferred embodiments of the invention and the accompanying drawings. These show:

[0045] Figure 1: a microscopic image of a full capsule of Example 1 at 5x magnification, obtained by encapsulating living disturbance cells in the carrier substrate;

[0046] Figure 2: a microscopic image of full capsules of Example 3 at 5x magnification, obtained by encapsulation of cell flour; and

[0047] Figure 3: Photographs of solid and hollow capsules obtained in the examples, from left to right: two hollow capsules with different dimensions, two solid capsules with different dimensions.

[0048] Embodiments of the present invention are explained below with exemplary reference to Figures 1 to 3.

[0049] Example 1: Production of full capsules with interference cells that have been cultured prior to encapsulation

[0050] Cryopreserved cells of the Atlantic sturgeon were thawed. These cryopreserved cells were initially obtained by isolating and cultivating cells from the tissue of an Atlantic sturgeon under standard conditions (20 °C and 2% CO2 in DMEM with 20% fetal calf serum). For 1000 caviar capsules, 10 ml of a sodium alginate solution with a mass-volume percentage of 1% (w / v) is used. For this solution, 1 g of sodium alginate is dissolved in 10 ml of water. A cell count of 10 million cells, obtained through this cultivation, is added to the sodium alginate solution at a rate of 1 million cells / ml. The resulting sodium alginate cell suspension is pumped at room temperature through a 1.5 mm diameter tube using a peristaltic pump. The outlet of the hose is located vertically 10 cm above a 0.1 M CaCl crosslinking solution.At the outlet, with a flow rate of 0.5 ml / min from the peristaltic pump, one drop per second is formed via a single-injection cannula (0.80 x 50 mm). This dropwise injection produces 1000 capsules within 20 minutes. The residence time of the formed capsules in the CaCl₂ crosslinking solution is at least 10 minutes for capsules formed at the end of this process and up to a maximum of 30 minutes for capsules formed at the beginning. After this time, the crosslinking solution is removed, yielding full capsules with a diameter of 1 to 2 mm (see Figures 1 and 3). After removal of the crosslinking solution, the capsules are washed and then placed in a brine solution with a concentration of 35 g NaCl / liter for storage. Example 2: Production of hollow capsules containing disruptive cells that were cultured prior to encapsulation.

[0051] Cryopreserved cells of the Atlantic sturgeon were thawed. The cryopreserved cells were initially obtained by isolating and cultivating cells from the tissue of an Atlantic sturgeon under standard conditions (20 °C and 2% CO2 in DMEM with 20% fetal calf serum). For 1000 caviar capsules, 10 ml of a 0.1 M CaCl₂ crosslinking agent solution are required. A cell count of 10 million cryopreserved cells is added to the 0.1 M CaCl₂ crosslinking agent solution at a rate of 1 million cells / ml. The resulting 0.1 M CaCl₂ cell suspension is pumped at room temperature through a 1.5 mm diameter tube using a peristaltic pump. The tube outlet is positioned vertically 10 cm above a sodium alginate solution with a mass-volume percentage of 2% (w / v). For this solution, 20 g of sodium alginate are dissolved in 1 L of water.At the outlet, with a flow rate of 0.5 ml / min from the peristaltic pump, one drop per second is dispensed via a single-injection cannula (0.80 x 50 mm). This dripping process produces 1000 capsules within 20 minutes. It is necessary to vary the drop point, for example, manually by changing the position of the vessel containing the sodium alginate solution. The residence time of the formed hollow capsules in the sodium alginate solution is at least 10 minutes for capsules formed at the end of the process and up to a maximum of 30 minutes for capsules formed at the beginning. After this time, the sodium alginate solution is removed, yielding hollow capsules with a diameter of 5 to 10 mm (see Fig. 3). After removing the sodium alginate solution, the capsules are washed with 0.1 M CaCl solution and then placed in a brine solution with a concentration of 35 g NaCl / Li-ter for storage.

[0052] Example 3: Production of full capsules with parasitic cells, which are encapsulated as cell meal

[0053] Atlantic sturgeon cells, initially obtained by isolating and culturing cells from Atlantic sturgeon tissue, are cultured under standard conditions (20 °C and 2% CO2 in DMEM with 20% fetal calf serum). Depending on the scale, cultivation can be carried out in standard cell culture vessels such as well plates, Erlenmeyer flasks, etc., in incubators, shaking incubators, or bioreactors. Upon reaching a cell count of at least 10 million cells, these are prepared as a cell suspension with 1–5 million cells / ml of medium for the production of cell meal. The cells in 10 ml of such a cell suspension with 1 million cells / ml are separated from the liquid by centrifugation (1000 rpm, 10 min at room temperature) and subsequently washed with 10 ml of isotonic saline solution (0.9% NaCl). The washed wet cell mass of 30-50 mg is then frozen at -80 °C for 24 h.The frozen cell mass is freeze-dried for 48 hours, yielding 3.5 to 4 mg of cell meal from an Atlantic sturgeon. The resulting cell meal is stored at -20 °C. To produce 1000 hollow capsules with an average cell count of 100,000 cells per capsule, 3.5 mg of cell meal is suspended in a 0.1 M CaCl₂ crosslinking agent solution. The resulting 0.1 M CaCl₂ cell meal suspension is processed analogously to Example 1 (see Fig. 1).

[0054] 2).

[0055] The features of the present invention disclosed in the foregoing description, the drawings and the claims may be important for the realization of the invention in its various embodiments, both individually and in combination or sub-combination.

Claims

Claims 1. Method for producing capsules containing biological cells derived from at least one aquatic organism, comprising: Providing biological cells derived from at least one aquatic organism, selected from isolated cells and a cell mass of in vitro cultured cells; Providing a carrier substrate solution and a crosslinking solution for the carrier substrate solution for encapsulating the cells; Encapsulation of the cells with the carrier substrate solution and the crosslinking solution, whereby the capsules containing the cells are obtained; and Separate and preferably wash the capsules.

2. The method of claim 1, wherein the capsules are full capsules and the encapsulation step comprises: Adding the cells to the carrier substrate solution, resulting in a suspension; Dropping the obtained suspension into the crosslinking solution yields full capsules containing the cells; and Separating and preferably washing the full capsules.

3. Method according to claim 2, wherein the diameter and shape of the full capsules are adjusted by adjusting the size and drop height of the drops of the obtained suspension during infusion.

4. The method of claim 1, wherein the capsules are hollow capsules and the encapsulation step comprises: Adding the cells to the crosslinking solution to obtain a suspension; Dropwise introduction of the obtained suspension into the carrier substrate solution, resulting in hollow capsules containing the cells; and Separation and preferably washing of the hollow capsules.

5. The method of claim 4, wherein the diameter of the hollow capsules is adjusted by adjusting the size and drop height of the drops of the obtained suspension during infusion, as well as by adjusting the residence time of the drops in the carrier substrate solution.

6. The method of any one of claims 2 to 5, wherein, in the case of solid capsules, the provided carrier substrate solution and, in the case of hollow capsules, the provided crosslinking solution, contain additives selected from one or more of colorants, flavorings, spices, vitamins, and trace elements.

7. Method according to any one of claims 1 to 6, wherein the isolated cells have been obtained by biopsy from organs of a living or dead animal.

8. Method according to any one of claims 1 to 6, wherein the cell mass is formed as cell flour.

9. Method according to any one of claims 1 to 8, wherein the carrier substrate solution is an alginate solution.

10. The method of claim 9, wherein the alginate solution is a sodium alginate solution.

11. Method according to any one of claims 1 to 10, wherein the crosslinking solution is a solution containing divalent cations.

12. The method of claim 11, wherein the divalent cation-containing solution is a Ca 2+ -containing solution.

13. Method according to any one of claims 1 to 12, wherein the cells are obtained from fish, molluscs and / or crustaceans.

14. The method of claim 13, wherein the molluscs are selected from Aculifera and Conchifera.

15. Method according to claim 13, wherein the crustaceans are selected from Remipedia, Cephalocarida, Branchi-opoda, Malacostraca, Ostracoda and Maxillopoda.

16. The method of claim 13, wherein the fish are selected from the families of sturgeon and salmonids.

17. Method according to claim 16, wherein the sturgeon are selected from sterlet, Atlantic sturgeon, Siberian sturgeon, Russian sturgeon and Beluga.

18. A method according to any one of claims 13 to 16, wherein the capsules obtained are transferred to a brine solution after separation.

19. Capsules containing biological cells in a hydrogel derived from at least one aquatic organism, wherein the capsules are preferably obtainable according to the method according to any one of claims 1 to 18.

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