Microalgae drying

The microalgae are cultured in bioreactors under solar or artiflcial light in the presence of carbon dioxide and salts. The bioreactors may be closed systems made of polyethylene sleeves rather than open pools. Optimal conditions for pigment production are low to medium light intensity and medium temperatures (20 to 30°C). Pigment extraction is achieved by cell breakage, extraction into water or buffered solution, and centrifugation to separate out the filtrate. The filtrate may then be partly purified and sterilized by microfiltration and spray dried or lyophilized. 

Lobbying by other P-carotene producers — In addition to approvals of mixed carotenes from palm oil, P-carotene from Dunaliella microalgae, and other natural products, the EU Health and Consumer Protection Directorate General was asked for an opinion on the safety of P-carotene from a dried biomass source, obtained from a fermentation process with Blakeslea trispora for use as a coloring matter for foodstuffs. 

SCFE of lipids from two freeze-dried microalgae species were studied (Po-lak et al., 1989). 

Photosynthetic microalga Haematococcus pluvicdis) vfikS inoculated at 2.0 kg dry cell rn and cultured in a basal medium (containing yeast extract, acetate, asparagine, and some metals) under illumination by fluorescent lamps. The cell concentrations are shown in Table P4.4. 

Microalgae samples Spirulina platensis) consisted of air-dried microalgae with 6% moisture weight, from Algamar S.A. (Pontevedra, Spain), stored under dry and dark conditions. 

There are lots of research applications published regarding PLE and analysis of various compoimds in food and agricultural materials, for example pesticides in rapeseed (38), babyfood (39) and strawberries (40), lipids in com and oats (41) and in egg-containing foods (42), acrylamide in food samples (43), carotenoids in processed food (44), xanthones and flavanones in root bark (45), tocopherols in seeds and nuts (46), antioxidants in microalgae (47) and anthocyanins and total phenolics in dried red grape skin (48). More discussions... 

Astaxanthin is a high-value carotenoid produced from microalgae that is produced commercially. Astaxanthin is ubiquitous in nature, especially in the marine environment, and is responsible for eliciting the pinkish-red hue to the flesh of salmonids, shrimp, lobster and crayfish. Cultivation methods have been developed to produce Haematococcus containing 1.5-3.0% astaxanthin by dry weight, with potential applications as a pigment source in aquaculture, poultry feeds and in the nutraceutical area. " ... 

The synthesis of microbial fat by bacteria is often ignored because the average fat concentration in dry biomass does not exceed 10%. However, there are strains of Arthrobacter sp., Mycobacterium, and Corynebacterium that are able to accumulate from 30 to 80% lipids in dry matter. Unfortunately, there are other problems related to low growth rates and yields of bacteria, lipid extraction, and the possible allergeiucity and toxicity of the resulting lipids. Microalgae (e.g., Botryococcus braunii and Chlorella pyrenoidosa) serve as attractive sources of PEFA. Dry biomass fat can amount to as much as 85% (Kay, 1991). Moreover, microalgae are a very... 

---