Despite the name, blue spirulina isn't simply a blue version of green spirulina. Green spirulina is the whole dried spirulina biomass. Blue spirulina is made by extracting phycocyanin, the naturally blue pigment found inside spirulina, and drying that extract into a powder. That difference matters when you're using it in food or drinks.
Why is one blue and the other green?
Whole spirulina contains several naturally occurring pigments, including green chlorophyll and blue phycocyanin. Together, they give ordinary spirulina its familiar dark green colour.
Blue spirulina is produced by separating out the water-soluble phycocyanin fraction. Once the green biomass is removed, you're left with an intensely blue ingredient that can be used to colour pale foods and drinks.
That's why adding ordinary spirulina to a latte won't give you the same result. You're adding the green material along with the blue pigment.
Which one should you use?
If you want to make a blue latte, lemonade, cocktail, gelato, soft serve, frosting or glaze, use blue spirulina.
It gives you a much cleaner blue without bringing the dark green colour of whole spirulina into the recipe.
Green spirulina makes more sense when you actually want spirulina itself to be a visible part of the product — for example, in green smoothies, smoothie bowls or other recipes where its characteristic colour is expected.
The two ingredients can come from the same organism, but they're being used for very different reasons.
What about taste?
There's a difference here too.
Whole green spirulina has a much more noticeable spirulina character, particularly as you increase the amount used.
Blue spirulina is an extract rather than the whole biomass, so it is considerably easier to use in products where you want the colour to stand out without making spirulina the dominant character of the recipe.
That makes it particularly useful for drinks and desserts where the blue is supposed to complement an existing flavour rather than become the flavour itself.
Quick comparison
- What is it?
- Blue spirulina: phycocyanin-rich extract. Green spirulina: whole spirulina biomass.
- Colour
- Blue spirulina: vivid blue. Green spirulina: dark green.
- Typical use
- Blue spirulina: natural blue colouring. Green spirulina: spirulina as an ingredient.
- Flavour impact
- Blue spirulina: relatively mild. Green spirulina: more noticeable.
- Good for
- Blue spirulina: drinks, desserts, frosting and other blue creations. Green spirulina: smoothies, bowls and green formulations.
FAQ
Can you substitute one for the other?
Not if colour matters. If a recipe calls for blue spirulina because it's supposed to be blue, replacing it with ordinary spirulina will give you a very different result. Green spirulina is the whole ingredient. Blue spirulina is the part we're interested in when we want that remarkable blue.