· When the amylose and amylopectin chains realign themselves, causing the liquid to gel, generally an undesirable effect.
· When native starch is heated and dissolves in water, the crystalline structure of amylose and amylopectin molecules are lost and they hydrate to form a viscous solution.
· If the viscous solution is cooled or left at lower temperature for long enough period, the linear molecules, amylose, and linear parts of amylopectin molecules retrograde and rearrange themselves again to a more crystalline structure.
· The linear chains place themselves parallel and form hydrogen bridges. In viscous solutions the viscosity increases to form a gel.
· Retrogradation can expel water from the polymer network.
· This is a process known as syneresis. A small amount of water can be seen on top of the gel.
· When native starch is heated and dissolves in water, the crystalline structure of amylose and amylopectin molecules are lost and they hydrate to form a viscous solution.
· If the viscous solution is cooled or left at lower temperature for long enough period, the linear molecules, amylose, and linear parts of amylopectin molecules retrograde and rearrange themselves again to a more crystalline structure.
· The linear chains place themselves parallel and form hydrogen bridges. In viscous solutions the viscosity increases to form a gel.
· Retrogradation can expel water from the polymer network.
· This is a process known as syneresis. A small amount of water can be seen on top of the gel.
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