Effects of Particle Size and Gelatinization of Job's Tears Powder on the Instant Properties

  • Han, Sung-Hee (Institute of Life Science and Natural Resources, Korea University) ;
  • Park, Soo-Jea (Division of Food Bioscience and Technology, College of Life Sciences and Biotechnology, Korea University) ;
  • Lee, Seog-Won (Department of Food & Nutrition, Yuhan College) ;
  • Rhee, Chul (Division of Food Bioscience and Technology, College of Life Sciences and Biotechnology, Korea University)
  • Published : 2010.03.31


The effects of particle sizes (small, medium and large sizes) and gelatinization treatment on the changes of the instant properties of Job's tears powder were investigated. The degree of gelatinization on the different particle size samples of Job's tears powder was the highest in the small particle size, and it also showed an increasing trend regardless of pregelatinizing whether it is or not as the particle size decreased from large particle size to small particle size. The water solubility index of the pregelatinized samples was high compared to that of ungelatinized samples regardless of particle size and temperatures. The water absorption and swelling power increased as particle size and temperature were increased. The dispersibility and sinkability of ungelatinized sample was increased as particle size and temperature were increased and it also showed lower value regardless of particle size and temperature. However, the dispersibility and sinkability of pregelatinized samples were shown to have the opposite result, such that the smallest particle size of pregelatinized sample had the lowest sinkability (11.3%). The turbidity of the pregelatinized small particle size was the highest by a factor of 1.08.


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