Abstract
in order to know the effect of hardness and temperature on the quality of bitter taste of juice, we prepared agar gels with grapefruit juice. They were prepared as follows: Sample 1-A: the juice was held at 10°C,35°C and 60°C; sample 1-B: the 1% agar gel with grapefruit juice was prepared and held at 10°C,35°C and 60°C; sample 2-A: juice and 1% agar gel were compared at 35°C; sample 2-B: 0.5% 1.0%and 1.5% agar gels were prepared and compared at 35°C.
The following results were obtained by chemical analysis and sensory evaluation. In the fresh juice of grapefruit,47.5 mg% of naringin,10.0 ppm of limonin,6.0 ppm of nomilin,1.44% of organic acid,9.2% of sugar and 90 mg% of reducing sugar were detected. The bitterness of the juice and the agar gel held at 60°C was significantly stronger than that held at 10°C. It was not affected by changes of the concentration, or the hardness of the agar gels.
