A microalgal flour having a particle size of between 30 and 150 μm and compressibility, measured by way of POWDER TESTER HOSOKAWA, of between 45 and 55%, has a flow value, determined according to a test A, of between 55 and 60% by weight for residue at 2,000 μm, dispersibility and wettability, expressed according to a test B, by the height of the product decanted in a beaker, of a value of between 0 and 2 mm; and a degree of humidification of a value of more than 70%, and preferably of more than 80%, of the total powder.