The effect of adding various oligosaccharides into the rice flour on its pasteurization and retrogradation to make Bak-Sul-Gi

초록

Four different oligosacchrides used to determine their effects on gelatinization and retrogradation of BakSulGi(BSG), Korean traditional rice cake, were cyclodextrin, isomaltooligosaccharide, fructooligosaccharide and maltote- traose, with 3 or 6%(w/w), based on the rice flour. From the Amylograph and blue value data, adding 6% cyclodextrin into the rice flour fastened the pasteurization process, and delayed the retrogradation in stored BSG at 4℃ for up to 3 days, probably due to its cyclic structure. Using rheometer, the hardness of freshly made BSG added with cyclodextrin was significantly lower than that of control BSG, and increased with stor-age time in all BSGs at refrigerated temperature. When using maltotetraose in rice flour, the hardness of BSG was also significantly low, but slightly higher than that of cyclodextrin. Hunter "L" value in BSG was decreased with the addition ofoligosaccharides, but the higher the level of oligosaccharide in BSG, the insignificant the Hunter "a",b”values of BSG. From the X-ray diffraction studies, the rice flour showed typical A pattern, and the crystallinities of all BSG gave amorphous V type. The highest peaks of X-ray patterns in BSG added with 6% cyclodextrin or maltotetraose were, however, lower than that of the control, meaning the less crystalline, retrograded starch in the former BSGs. Based on sensory evaluation, BSG added with all oligosacchrides did not show significantly different in taste, flavor, chewiness, moistness and overall preferences, with slightly darker color with storage time, compared to the control BSG.