Textural properties of Frozen stored Garaetteok supplemented with Agar and Casein

Abstract

ABSTRACTThe effects of agar and casein on the textural characteristics of frozen stored Garaetteok, a traditional Korean rice cake, were investigated over a 20-d storage period. Garaetteok was made from rice flour with and without the addition of agar (GA), casein (GC), and a mixture of agar and casein (GAC). The moisture content of control Garaetteok (G) significantly (P < 0.001) decreased during frozen storage, whereas those of GA and GAC showed no significant decrease, although GC showed less of a decrease than G. Although the hardness and retrogradation rate of all uncooked Garaetteoks significantly (P < 0.05) increased during frozen storage, the retrogradation rate of GC did not significantly increase. After cooking, GC was the least hard and had relatively low adhesiveness and no significant (P < 0.05) difference in cohesiveness and springiness regardless of frozen storage time. These results indicated that casein was an effective additive for frozen stored Garaetteok with relatively minimal impact on textural properties compared with G. However, although agar maintained the moisture content, it was not an effective additive because of the increase in the hardness and adhesiveness of cooked Garaetteok regardless of frozen storage time.