In the 5-7-day reddening phase, the cells are deprived of nutrients and subjected to intense sunlight, which makes them produce high levels of red astaxanthin as a protective mechanism against the environmental stress.
When the astaxanthin is at optimum levels, the cultures are harvested, washed and dried.
The resulting dried Haematococcus biomass (which contains about 2.5-3% astaxanthin) is currently sent to third party facilities where the lipid fraction, which includes astaxanthin, lutein, beta-carotene and canthaxanthin, is extracted using supercritical carbon dioxide to produce a purified oleoresin. This contains up to 12% astaxanthin complex.
In future, the extraction process will be brought in-house, however.