2 августа, 2015 
Malyar Starch must be modified before it can be used as an adhesive. Methods for opening the starch granules include heating, alkali treatment, acid treatment, and oxidation.
1. Heat Treatment
The simplest method of breaking up starch granules is well known to the cook. To thicken a sauce, cornstarch must be heated. During the heating process, the starch granules first swell and then burst with a coincident thickening of the suspension. The temperature at which this thickening occurs is called the gelation temperature. For starches in pure water, gelation occurs between 57 and 72°C [8]. Observation of gelled starch under a polarizing microscope indicates that the crystallinity of the starch granule is lost during the gelling process. However, the starch is not truly in solution but rather in a colloidal suspension. Suspensions of amylose and high-amylose starches have a tendency to harden and become solid upon cooling. This process is called retrogradation or setback and is a result of the tendency of linear molecules to align with one another. This aligning effect also means that at the same solids content, suspensions with a higher ratio of amylose to amylopectin have a higher viscosity.
2. Alkali Treatment
The gelation temperature can be lowered by the addition of sodium hydroxide to a starch suspension. If sufficient alkali is added, the starch can be induced to gel at room temperature.
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