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Method for spray drying a high-viscosity fluid product using a spraying device, wherein the method comprises projecting the fluid product out of an outflow opening of the spraying device for obtaining droplets of the fluid product, wherein the spraying device is arranged to cause a pressure drop in

Method for spray drying a high-viscosity fluid product using a spraying device, wherein the method comprises projecting the fluid product out of an outflow opening of the spraying device for obtaining droplets of the fluid product, wherein the spraying device is arranged to cause a pressure drop in the fluid product across the outflow opening which is larger than 15 bar and at least partially drying the droplets in a drying medium, such as air, to become particles.

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1. A method for spray drying a high-viscosity fluid product using a spraying device, comprising the steps of: generating a fluid jet of the fluid product projecting from an outflow opening of the spraying device and breaking the fluid jet into droplets of the fluid product by disturbing the fluid je

1. A method for spray drying a high-viscosity fluid product using a spraying device, comprising the steps of: generating a fluid jet of the fluid product projecting from an outflow opening of the spraying device and breaking the fluid jet into droplets of the fluid product by disturbing the fluid jet, wherein the step of disturbing the fluid jet comprises varying a pressure of the fluid product upstream of the outflow opening by vibrating an end of a control element, positioned in the fluid product upstream of the outflow opening at a predetermined distance to the outflow opening;wherein the spraying device is arranged to cause a pressure drop in the fluid product across the outflow opening which is larger than 15 bar; andat least partially drying the droplets in a drying medium, to become particles. 2. The method according to claim 1, wherein the pressure drop is larger than 100 bar. 3. The method according to claim 1, wherein the pressure drop is in the interval of 15-3000 bar. 4. The method according to claim 1, wherein the step of generating the fluid jet of the fluid product comprises: providing the fluid product to an outflow opening at a predetermined feed pressure. 5. The method according to claim 1, wherein the predetermined distance is 2-1500 μm. 6. The method according to claim 1, wherein the control element is vibrated using at least one of a piezo-electric element, an electrostrictive element, an acoustic element, an electromagnetic actuator, a voice-coil, or mechanical means. 7. The method according to claim 1, wherein the pressure of the fluid product upstream of the outflow opening is varied at a predetermined, substantially constant, frequency. 8. The method according to claim 7, wherein a droplet diameter is determined by controlling the predetermined frequency and/or material throughput through the outflow opening. 9. The method according to claim 7, wherein the predetermined frequency is chosen such that a distance between two droplets consecutively ejected at the outflow opening is greater than or equal to two times the droplet diameter. 10. The method according to claim 7, wherein the predetermined frequency is in the interval of 500-200000 Hz. 11. The method according to claim 1 further comprising a step of projecting the fluid product out of a plurality of outflow openings of the spraying device for obtaining droplets of the fluid product. 12. The method according to claim 1, wherein a viscosity of the fluid product, determined at a spray drying temperature which in use prevails in the outflow opening and a shear rate as in use present in the outflow opening, is higher than 200 mPa·s. 13. The method according to claim 1, wherein a transverse dimension of the outflow opening is smaller than or equal to 150 μm. 14. The method according to claim 4, wherein the feed pressure is kept substantially constant. 15. The method according to claim 14, wherein the feed pressure is kept substantially constant by means of applying a pressure to the fluid product hydraulically or pneumatically. 16. The method according to claim 14, wherein the feed pressure is kept substantially constant by means of a pump. 17. The method according to claim 1, wherein the feed pressure is in the interval of 15-3000 bars. 18. A powder produced using the method according to claim 1. 19. The powder according to claim 18 having a monodispersity index smaller than 1. 20. The powder according to claim 18, having an average particle diameter (d50) smaller than or equal to 250 μm. 21. The powder according to claim 18, wherein less than 5% of the volume of the powder particles consists of gas and/or voids. 22. The powder according to claim 18, comprising a food product mainly comprising protein, carbohydrate, fat, or a combination thereof. 23. The powder according to claim 18 having a bulk density larger than or equal to 550 kg/m3. 24. A powder produced using a spraying device by: projecting a fluid product out of an outflow opening of the spraying device for obtaining droplets of the fluid product, wherein the spraying device is arranged to cause a pressure drop in the fluid product across the outflow opening which is larger than 15 bar; andat least partially drying the droplets in a drying medium, such as air, to become particles of the powder;the powder comprising fat, having a bulk density higher than a reference bulk density according to the equation RBD=ZFD−5×FCwherein RBD represents the reference bulk density in kg/m3, ZFD represents a zero-fat-density which represents the bulk density (in kg/m3) of a powder containing no fat, and FC represents the fat content of the powder in percents by weight, wherein ZFD is equal to or larger than 650 kg/m3, preferably equal to or larger than 800 kg/m3. 25. The method according to claim 2, wherein the pressure drop is larger than 300 bar. 26. The method according to claim 3, wherein the pressure drop is in the interval of 50-600 bar. 27. The method according to claim 5, wherein the predetermined distance is 15-500 μm. 28. The method according to claim 7, wherein the predetermined frequency is chosen such that a distance between two droplets consecutively ejected at the outflow opening is greater than or equal to three times the droplet diameter. 29. The method according to claim 13, wherein the transverse dimension of the outflow opening is smaller than or equal to 100 μm. 30. The method according to claim 13, wherein the transverse dimension of the outflow opening is smaller than or equal to 80 μm. 31. The method according to claim 4, wherein the feed pressure is in the interval of 50-600 bars. 32. The powder according to claim 18, having a monodispersity index smaller than 0.7. 33. The powder according to claim 18, having a monodispersity index smaller than 0.1. 34. The powder according to claim 18 having a bulk density larger than or equal to 650 kg/m3.