Abstract
This study was carried out to investigate the effects of modified starch, sugars and enzymatic hydrolysis with ${\beta}-amylase$ on extending the self-life of Injulmi, a Korean soft and glutinous rice cake, in terms of maintaining a soft texture. The Injulmi was prepared with or without kneading of waxy rice flour, NaCl and water mixture. The Injulmi was stored at -20, 4 and $20^{\circ}C$ and the hardness was measured to calculate the Avrami exponents during storage. The results showed that cold heading and enzymatic hydrolysis with ${\beta}-amylase$ before steaming of the waxy rice dough significantly extended the self-life on the basis of the Avrami equation. Among the various additives including different kinds of starches, sugars and polymannuronic acid, the addition of 1.5% tapioca starch, 8.0% of glucose or 3.0% of polymannuronic acid was also effective for delaying the retrogradation phenomena during storage. However, despite the effectiveness of these treatments, the Injulmi developed hardness within 2-3 days at $4^{\circ}C$ and within 4 days at $20^{\circ}C$ while storage at $-20^{\circ}C$ showed a storage stability that was maintained over x days. Sensory showed the Injulmi prepared with NOVA-0.005, GL-8.0 had a lower hardness than that of the other treatments.