METHOD FOR PRODUCING A GRANULAR BIOMASS WHICH CONTAINS AN OXIDATION-SENSITIVE VALUABLE SUBSTANCE

Abstract

According to the invention, it has been found that a particulate biomass containing an oxidation-sensitive material of value can be converted into a particularly easy-to-handle product in a gentle manner if it is subjected to a granulation with the addition of an agglomeration auxiliary.

Claims

1-17. (canceled)

18. A method for producing a particulate biomass having an oxidation-sensitive material of value, said method comprising granulating a particulate starting biomass in the presence of an agglomeration auxiliary.

19. The method of claim 18, wherein carbohydrates, or modified carbohydrates, are used as the agglomeration auxiliary.

20. The method of claim 18, wherein polysaccharides, or modified polysaccharides, are used as the agglomeration auxiliary.

21. The method of claim 18, wherein the agglomeration auxiliary is selected from the group consisting of: guaran; gum Arabic; guar gum; locust bean gum; xanthan gum; agar; carrageenan; a maltodextrin; starch; cellulose or its derivatives; hemicellulose or its derivatives; alginic acid; maltodextrin; and mixtures thereof.

22. The method of claim 21, wherein said agglomeration auxiliary is selected from the group consisting of: modified cellulose; maltodextrin; and mixtures thereof.

23. The method of claim 18, wherein proteins are used as the agglomeration auxiliary.

24. The method of claim 18, wherein organic polymers are used as the agglomeration auxiliary.

25. The method of claim 18, wherein inorganic substances are used as the agglomeration auxiliary.

26. The method of claim 18, wherein the starting biomass is obtained by spray drying a fermentation broth containing the biomass.

27. The method of claim 18, wherein the biomass comprises cells from the taxon Labyrinthulomycetes.

28. The method of claim 18, wherein the oxidation-sensitive material of value is a PUFA.

29. The method of claim 18, wherein: a) the agglomeration auxiliary is selected from the group consisting of: guaran; gum Arabic; guar gum; locust bean gum; xanthan gum; agar; carrageenan; a maltodextrin; cornstarch; tapioca starch; potato starch,; cellulose or its derivatives; hemicellulose or its derivatives; alginic acid; maltodextrin; casein, gelatine, collagen; wheat gluten; lignosulphonate; polymethylolcarbamides; polyacrylic acids; polyvinyl alcohols; bentonites; hexametaphosphate and mixtures thereof; b) the particulate starting biomass has been obtained by spray drying a fermentation broth containing the biomass; c) the biomass comprises cells from family Thraustochytriaceae; d) the oxidation-sensitive material of value is an omega-3-fatty acid.

30. A particulate biomass having an oxidation-sensitive material of value, comprising an agglomeration auxiliary in an amount of from 0.05 to 6% by weight.

31. The particulate biomass of claim 30, wherein the agglomeration auxiliary is a carbohydrate or a modified carbohydrate.

32. The particulate biomass of claim 30, wherein said biomass comprises a hydrophilic or hydrophobic silicate in an amount of from 0.05 to 6% by weight.

33. The particulate biomass of claim 30, wherein at least 80% by weight of the particles have a particle diameter (grain size) of from 100 to 2000 μm.

34. The particulate biomass claim 30, wherein said biomass comprises cells from the taxon Labyrinthulomycetes.

35. The particulate biomass of claim 30, wherein the oxidation-sensitive material of value is a PUFA.

36. The particulate biomass of claim 30, comprising an agglomeration auxiliary in an amount of from 0.4 to 4% by weight, wherein: a) the agglomeration auxiliary is selected from the group consisting of: carboxymethylcellulose; hydroxypropylmethylcellulose, maltodextrin; and a hydrophilic or hydrophobic silicate in an amount of from 0.1 to 5% by weight; b) at least 90% by weight of the particles have a particle diameter (grain size) of from 100 to 1000 μm; c) the biomass comprises cells selected from one or more genera selected from the group consisting of: Thraustochytrium; Schizochytrium; Aurantiochytrium; Oblongichytrium; and Ulkenia; and d) the oxidation-sensitive material of value is an omega-3-fatty acid.

37. A feedstuff or foodstuff comprising the particulate biomass of claim 30.

Description

WORKING EXAMPLES

Example 1

Production of Spray-Dried Biomass

[0142] To produce DHA, the strain Aurantiochytrium limacinum SR21 was used. This is deposited at the NIBH under FERM BP-5034 and also at the IFO under IFO 32693. The strain A. limacinum SR21 was originally isolated from seawater and called Schizochytrium limacinum SR21 (Nakahara et al. 1996, JAOCS, 73(10); Honda Mycol. Res. 1998). On account of the new classification, it was assigned to the new genus Aurantiochytrium and renamed accordingly.

[0143] The fermentation of the strain was carried out in a medium which comprise 50% synthetic seawater (Sigma Aldrich) and furthermore comprise the following components: 60 g/l glucose, 0.7 g/l corn steep liquor (Sigma Aldrich), 2 g/l (NH.sub.4).sub.2SO.sub.4 and 3 g/l KH.sub.2PO.sub.4.

[0144] The fermentation was carried out at 28° C., a pH of 4.0, an aeration rate of 0.5 vvm and a stirring of 200 rpm for 60 hours. After ending the fermentation, an antioxidant was added to the fermentation broth and the fermentation broth was then heated at 60° C. for at least 20 minutes.

[0145] Then, a two-stage drying of the biomass was carried out: Firstly, the fermentation broth was concentrated to a dry mass of about 20% by weight by evaporation. Then, spray drying of concentrated fermentation broth was carried out using a Production Minor™ Spray Dryer (GEA NIRO) at an inlet temperature of the drying air of 340° C. Spray drying produced a powder with a dry mass of more than 95% by weight.

Example 2

Granulation of Spray-Dried Biomass Using Carboxymethylcellulose as Agglomeration Auxiliary

[0146] For the agglomeration of the spray-dried particles from Example 1, the granulator ProCell-LabSystem (Glatt, Germany) was used to carry out a fluidized-bed granulation. Here, the insert GF3 was used. The fine, spray-dried biomass powder was fed to the fluidized bed and a carboxymethylcellulose solution (4% by weight blanose, dissolved in water) was sprayed in and thus finely distributed in the fluidized bed such that a final concentration of carboxymethylcellulose of 3% by weight was established. The solvent was evaporated by heating the incoming air to 60° C. The incoming air rate was adjusted such that a fluidization of the agglomerated particles is possible. This was achieved by regulating the amount of incoming air to about 80 m.sup.3/h. As soon as the agglomerates have reached the desired particle size, they were no longer fluidized on account of their weight and were able to be removed at the lower end of the fluidized bed. The residence time of the particles in the fluidized bed was thus established via the rate of particle growth since the particles had to grow from fine, spray-dried particles to the relatively large agglomerate in order to leave the fluidized bed.

[0147] The pregiven conditions corresponded to the standard conditions of a thermal granulation.

[0148] The product thus obtained exhibited, compared to the starting biomass, significantly improved product properties, in particular a considerably improved free-flowability.

Example 3

Granulation of Spray-Dried Biomass Using Maltodextrin DE 3.5 as Agglomeration Auxiliary

[0149] For the agglomeration of the spray-dried particles from Example 1, the granulator ProCell-LabSystem (Glatt, Germany) was used to carry out a fluidized-bed granulation. Here, the insert GF3 was used. The fine, spray-dried biomass powder was fed to the fluidized bed, and a maltodextrin DE 3.5 solution (25% by weight maltodextrin DE 3.5, dissolved in water) was sprayed in and thus finely distributed in the fluidized bed, such that a final concentration of maltodextrin DE 3.5 of 3% by weight was established. The solvent was evaporated by heating the incoming air to 60° C. The incoming air rate was adjusted such that a fluidization of the agglomerated particles is possible. This was achieved by regulating the amount of incoming air to about 80 m.sup.3/h. As soon as the agglomerates have reached the desired particle size, these were no longer fluidized on account of their weight and could be removed at the bottom end of the fluidized bed. The residence time of the particles in the fluidized bed was thus established by the rate of particle growth since the particles had to grow from the fine, spray dried particle to the relatively large agglomerate in order to leave the fluidized bed.

[0150] The pregiven conditions corresponded to the standard conditions of a thermal granulation.

[0151] The product obtained in this way exhibited, compared to the starting biomass, considerably improved product properties, in particular a considerably improved free-flowability.

Example 4

Granulation of Spray-Dried Biomass Using Maltodextrin 18.9 as Agglomeration Auxiliary

[0152] For the agglomeration of the spray-dried particles from Example 1, the granulator ProCell-LabSystem (Glatt, Germany) was used for carrying out a fluidized-bed granulation. Here, the insert GF3 was used. The fine, spray-dried biomass powder was fed to the fluidized bed, and a maltodextrin 18.9 solution (40% by weight maltodextrin 18.9, dissolved in water) was sprayed in and thus finely distributed in the fluidized bed, such that a final concentration of maltodextrin DE 18.9 of 3% by weight was established. The solvent was evaporated by heating the incoming air to 60° C. The incoming air rate was adjusted such that a fluidization of the agglomerated particles is possible. This was achieved by regulating the amount of incoming air to about 80 m.sup.3/h. As soon as the agglomerates have reached the desired particle size, these were no longer fluidized on account of their weight and could be removed at the bottom end of the fluidized bed. The residence time of the particles in the fluidized bed was thus established by the rate of particle growth since the particles had to grow from the fine, spray dried particle to the relatively large agglomerate in order to leave the fluidized bed.

[0153] The pregiven conditions corresponded to the standard conditions of a thermal granulation.

[0154] The product obtained in this way exhibited, compared to the starting biomass, considerably improved product properties, in particular a considerably improved free-flowability.