Studies on the Dried Agar Jelly

Part V. Properties of agar jelly contained xylose

Abstract

Effects of xylose on the dried agar jelly were examined. When agar gel contained xylose, its muximum ultimate strength was recognized at the concentration of about 50% xylose. When agar solution containing 50% sugar was boiled for 2hr., the ultimate strength of gel was slightly changed by sucrose and xylit, but decreased to the negligible value by xylose. At the same time, drop in pH value and increase of browning color were observed by use of xylose. The gel formation ability of agar that was once reduced with addition of xylose could not be recovered when xylose of agar gel was washed off. Decrease of the ultimate strength and drop in pH value of agar gel added 50% xylose were prevented consisderably by use of the buffer solution. From these results, the decrease of the ultimate strength was considered to be caused by the low pH value which was due to the added xylose. The ultimate strength of agar jelly contained xylose and corn syrup was little affected in the condensing process of the jelly. The drying rate of agar jelly contained corn syrup and xylose or xylit at 60°C was more accelerated under the low humidity but was more delayed under the high humidity than that of sucrose jelly.