Spirulina is a blue-green algae that thrives in warm, alkaline fresh water ponds. Its name comes from its spiral or helical configuration (when seen under a microscope). It contains the green pigment called chlorophyll, as well as the blue pigment - photocyanin.
Despite being single-celled, spirulina is bigger than most other forms of algae and is large enough to be visible to the naked eye. The algae can grow up to 0.5mm and tends to exist in colonies. This allows it to be easily gathered in large masses.Some species of spirulina survive even under intense heat. When the fresh water pond in which they exist dries up due to a surge in temperature, spirulina sticks to the rocks in the pond and forms a frosty white layer. This frosted form of the alga tastes very sweet as the protein, predominantly present in them, turns to polysaccharides.
It is generally speculated that the “manna from heaven” that is referred to in the Bible may actually have been dried spirulina that the wandering Israelites gathered from rocks. It is supposed to have tasted like “wafers made with honey”.
The unique ability of the algae to sustain heat has helped it to retain its nutrients even after rigorous processing.