Method of separating lipids from a lysed lipids containing biomass

1. A method of separating a polyunsaturated fatty acids (PUFAs)-containing lipid from the debris of a biomass, comprising the following steps:

a) providing a suspension of a biomass comprising cells which contain a PUFAs-containing lipid;

b) lysing the cells of the biomass;

c) heating the suspension obtained in step b) to a temperature of 80° C. to 100° C., and adjusting the pH to a value of 9.0 to 11.5;

d) maintaining the temperature and pH value in the ranges of paragraph c) for at least 10 hours thereby forming a demulsified suspension;

e) harvesting the PUFAs-containing oil by:

i) adding an acid to the demulsified suspension to adjust it to a pH of 5.5 to 8.5;

ii) subsequently separating the resulting oil-containing light phase from the water, salt and cell debris-containing heavy phase;

wherein:

after lysing cells in step b), and prior to steps c) and d), the suspension is concentrated to a total dry matter content of 30 to 60 wt.-% by evaporation of water;

more than 90 wt.-% of the oil contained in the initial biomass is separated and isolated;

the method is carried out without the addition of any salts for salting out the oil.

2. The method of claim 1 , wherein, in step c) the suspension of lysed cells obtained in step b) is heated to a temperature of 85° C. to 95° C., and the pH is adjusted to a value of 9.0 to 11.0 and in step d), the temperature and pH are maintained for a period of 20 to 36 hours.

3. The method of claim 1 , comprising as a further step the conversion of the water, salt, residual oil and cell debris containing heavy phase into a dried biomass with a total dry matter content of more than 90 wt.-%.

4. The method of claim 3 , wherein conversion into a dried biomass is carried out by concentrating the heavy phase to a dry matter content of 30-50 wt.-% and subsequently spray granulating using a fluidized bed granulator.

5. The method of claim 1 , wherein the suspension is provided as a fermentation broth with a biomass density of at least 80 g/l.

6. The method of claim 5 , wherein the cells are selected from algae, fungi, protists, bacteria, microalgae, plant cells, and mixtures thereof.

7. The method of claim 5 wherein the cells are of the genus Schizochytrium.

8. The method of claim 4 , wherein the suspension is provided as a fermentation broth with a biomass density of at least 80 g/l.

9. The method of claim 8 , wherein the cells are selected from algae, fungi, protists, bacteria, microalgae, plant cells, and mixtures thereof.

10. The method of claim 8 , wherein the cells are of the genus Schizochytrium.

11. The method of claim 1 , wherein separation of step e)ii) is by filtration or centrifugation.

12. The method of claim 1 , wherein, the suspension is concentrated to a total dry matter content of preferably 35 to 55 wt.-% by evaporation of water at a temperature not higher than 100° C.

13. The method of claim 12 , wherein said temperature is 80° C. to 90° C.