PROCESS FOR PRODUCING STARCH FROM MICROALGAE

The process described relates to the production of starch from microalgae through cultivation in an autotrophic stage followed by a subsequent heterotrophic stage. The autotrophic stage is used to produce the inoculum for cultivation under heterotrophic conditions. In the heterotrophic reactor starch accumulates in the algae. Cultivation under heterotrophic conditions is carried out with the addition of antimicrobials of natural origin of the phenol type on a growth medium such as for example one based on whey, in order to reduce contamination by bacteria and fungi. During this stage the starch content in the algae is monitored in order to maximise output. The microalgae used in the process are suitably selected for growth under the conditions reported. Oil and carotenoids are also extracted from the biomass in addition to starch. The process provides a method for the more efficient production of starch in comparison with conventional production and a method for controlling contaminants under heterotrophic growth conditions.