Gellan is a popular gelling agent and comes in two varieties, high acyl or low acyl. High acyl gellan typically results in soft, elastic gels while low acyl gellan creates hard, brittle gels. They are often used together to create a variety of textures. They can also be used in spherification.
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Typically 0.5-1.25% Gellan is used for making gels.
Gellan must be heated to hydrate.
The gels created by gellan are highly dependent on the presence of calcium and potassium in the mixture. Even though Gellan sets at high temperatures, it must also be heated to hydrate it.