TWL+AGAR+and+CARRAGEENAN

What do carrageenan and agar have in common? Question 1: Think about the chemical structure of carrageenan and agar - what do they have in common?

Answer: Carrageenan has a long chian of __galactose__ residues linkage, giving it a high molecular weight. Carrageenan is composed of linear galactan polysaccharides. Agar has similar structure as carrageenan. Agar is a polysaccharide derived from red algae, which contains sulfated __galactose__ monomers.

Question 2: What are the differences between kappa, iota and lambda carrageenan? Why?

Answer:

Repeating Unit:

Lambda: //__D-Galactose-2-Sulphate and D-Galactose-2, 6-Disulphate__// is the repeating unit.

Kappa: __//D-Galactose-4-Sulphate linked with 3, 6-anhydrous-D-Galactos//e__ is the repeating unit.

Iota: __//D-Galactose-4 Sulphate linked with 3, 6-anhydrous-D-Galactose-2-Sulphate//__ is the repeating unit.

Solubility:

Lambda: __//Very soluble in cold water.//__

Kappa: __//Dissolves only slightly in cold water.//__

Iota: __//Needs to be heated to be soluble in water.//__