will remain liquid.
If the bead is eaten straight away, as the outside jellified layer is broken, the liquid contained will be
released, giving a surprising explosion in the mouth. However, these beads are not very stable over
time. Slowly, the calcium will diffuse into the centre of the bead (even after removal from the calcium
bath), and it will become entirely jellified.
A quantity of alginate should be added so that the final alginate concentration of the mixture is
between 0.5 and 1 %. Although a higher concentration will form a bead more quickly, it will cause the
liquid to thicken substantially, which will reduce its “explosion” effects on eating.
The calcium concentration of the solution into which the beads are pipetted should contain between 1
and 5 % calcium – the most commonly used sources of calcium are calcium chloride and calcium
lactate – both of which are soluble calcium salts.
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Gels formed with alginates have the amazing ability of withstanding heating to temperatures as high
as 150°C without melting. This means that these beads can be either placed in a boiling liquid, or
placed on a hot piece of fish, and they will not melt. However, once the gel has melted, it cannot be
reformed – unlike agar agar, alginate based gels are not thermoreversible.
An alginate containing solution does not need to be heated to dissolve the alginate. This means that is
can be used, unlike agar agar, for raw preparations. However, alginates are not very soluble in cold
water, so the mixture needs to be very well agitated in order to disperse and fully hydrate the alginate.
This can be carried out by mixing the liquid in an electric mixer while adding the alginate. It is often
recommended that sugar is added to these alginate mixes – if the alginate is premixed with a
significant amount of sugar, it will disperse more evenly when added to the liquid mixture.
Solutions used to make these beads should not contain any salt. Alginates are extracted from