The reactions of octenyl succinic anhydride (OSA) at 3% and 15% concentrations (based on weight of starch) with granular and debranched starch forms of waxy rice and waxy potato starches were investigated and compared. Reaction efficiencies of debranched starches with 3% OSA (83.6–87.4%) were significantly higher than those of the granular starches (51.2–56.1%), but their recovery yields were lower (80–85% and 94–98% for debranched and granular starches, respectively). Similar trends were found for the starches modified with 15% OSA but with less reaction efficiencies. Molecular weights of the modified debranched starches were substantially higher than the unmodified ones, presumably due not only to the substituted groups, but also the association of starch chains. Native, debranched, 3% OS granular and 3% OS debranched starches were then evaluated as a fat replacer in a low-fat salad dressing. Viscosities of the dressings incorporated with native and OS granular starches were reduced markedly after storage for 3 d, while the consistency and appearance of the dressings containing debranched starches, either modified or not, were similar to commercial low-fat dressing at up to 90 d storage. Relative calorie values of the dressings containing debranched starches were approximately 50% and 10% less than the reference formula and commercial dressing, respectively.
Debranched waxy starch; Granular starch; Octenyl succinic anhydride; Molecular structure; Low-fat salad dressing; Emulsifier