The present invention is directed to a process for the manufacture of synthetic food-grade astaxanthin with a content of dichloromethane ≤ 250 ppm comprising the following steps: a) Providing synthetic astaxanthin crystals containing dichloromethane in a reactor； and b) Adding methanol to the synthetic astaxanthin crystals in an amount to obtain a suspension of synthetic astaxanthin in methanol, whereby the amount of synthetic astaxanthin in said suspension is in the range of from 5 to 70 weight-%, based on the total weight of the suspension, and closing the reactor； and c) bringing the suspension obtained in step b) to a temperature in the range of from 80 to 140°C； and d) Maintaining the suspension at the temperature as reached in step c)； and e) Bringing the methanolic synthetic astaxanthin suspension to atmospheric pressure by releasing overpressure； and f) Cooling the synthetic astaxanthin suspension to a temperature in the range of 10 to 35°C； and g) Filtering off the synthetic astaxanthin crystals and drying them； whereby during the process the total amount of synthetic astaxanthin is not completely solved in the methanol at the same time, and whereby a synthetic food-grade astaxanthin with a content of dichloromethane <； 250 ppm is obtained. Instead of synthetic astaxanthin crystals also a solution of synthetic astaxanthin in dichloromethane can be used as starting material.
