The invention relates to a method for conditioning a biomass of microalgae of the genus Chlorella, preferably Chlorella protothecoides, produced by fermentation under heterotrophic conditions and in the absence of light for the preparation of a flour having an optimised sensory profile, the method being characterised in that it comprises the steps of: collection of the biomass directly at the end of the fermentation, and storage of same for less than 8 hours prior to conditioning; HTST treatment of the thus recovered and stored biomass for between 30 seconds and 1 min 30, at a temperature below 70 ° C.; and washing of the biomass with at most 3 volumes of water per volume of biomass.