Cold Soluble Starch

Effectiveness of Granular Cold-Water-Soluble Starch as a Controlled-Release Matrix.

J. Chen and J. Jane. Copyright 1995 by the American Association of Cereal Chemists, Inc.

Granular cold-water-soluble (GCWS) starches (waxy maize, normal maize, Hylon-5, and Hylon-7; amylose content less than 1, 28, 54, and 68%, respectively) prepared by alcoholic-alkaline treatment are potential encapsulation materials. The cold-water- soluble starch is desirable for encapsulation of volatile and toxic chemicals. Controlled release of atrazine encapsulated in the GCWS starch matrices was selected for the study. Results showed that atrazine was physically embedded in the starch matrices. GCWS Hylon-7 starch had the best encapsulation efficiency among all the starch types tested. The release rate of atrazine in aqueous ethanol solution (10%, v/v) was affected by starch cultivar, particle size, and release temperature. Changes of pH between 5 and 9 had no significant effect on the atrazine release rate. The release rate of GCWS starch-encapsulated atrazine decreased as amylose content and particle size increased; however, the release rate increased as the release temperature increased.