Enlarged granule starch stilt material for microencapsulated coatings

摘要

Enlarged granule starch useful as a protective stilt material in microencapsulated coatings to prevent premature rupture of the microcapsules. Starch granules are increased in size by alkali-swelling of the granules in aqueous slurry. The enlarged granules are then crosslinked to aid in preserving the enlarged granular form through subsequent aqueous coating applications and thermal drying steps. A combination of hydrocyclone starch granule sizing and granule treatment employing alkali-swelling and crosslinking substantially improves the yield of usable large granule stilt materials obtainable from prime grade wheat starch, and other bimodal granular starches such as barley and rye.