FLAVOR RETENTION IN PREGELATINIZED AND INTERNALLY FLAVORED STARCH EXTRUDATES

Corn starch (25% amylose content) was pregelatinized in a twin-screw e xtruder. The extrudate was ground and reextruded after adjusting moist ure content to 9, 13, or 17% (db) and blending with 5% (w/w) of flavor compounds cinnamaldehyde, eugenol, nonanoic acid, or 3-octanone. Init ial moisture content significantly influenced radial expansion, specif ic mechanical energy, and flavor retention. Significantly higher flavo r retention was obtained when flavor was injected into the extruder ba rrel as compared to preblending of flavors in pregelatinized starch. F lavor retention upon extrusion was lower with pregelatinized starch th an with raw starch.