Astaxanthin is a powerful antioxidant with various health benefits such as prevention of age-related macular degeneration and improvement of the immune system, liver and heart function. To improve the post-harvesting
stability of astaxanthin used in food, feed and nutraceutical industries, the biomass of the high astaxanthin pro-ducing alga Haematococcus pluvialis was dried by spray- or freeze-drying and under vacuum or air at 20 °C to 37 °C for 20 weeks. Freeze-drying led to 41% higher astaxanthin recovery compared to commonly-used spray-drying. Low storage temperature (20 °C, 4 °C) and vacuum-packing also showed higher astaxanthin stability
with as little as 12.3 ± 3.1% degradation during 20 weeks of storage. Cost-benefit analysis showed that freeze-drying followed by vacuum-packed storage at 20 °C can generate AUD$600 higher profit compared to spray-drying from 100 kg
H. pluvialis
powder. Therefore, freeze-drying can be suggested as a mild and more profitable
method for ensuring longer shelf life of astaxanthin from
H. pluvialis