Sorption Characteristics of Binary Mixture of Sugar and Sodium Chloride

저장상대습도(貯藏相對濕度)에 따른 당(糖)과 소금 이상혼합물(二相混合物)의 흡습특성(吸濕特性)

  • Oh, Hoon-Il (Department of Food Science & Technology, King Sejong University) ;
  • Kim, Woo-Jung (Department of Food Science & Technology, King Sejong University) ;
  • Park, Nae-Jung (Department of Chemical Engineering, College of Engineering, Hong-Ik University)
  • 오훈일 (세종대학 식품공학과) ;
  • 김우정 (세종대학 식품공학과) ;
  • 박내정 (홍익대학교 공과대학 화학공학과)
  • Published : 1983.01.01

Abstract

A study was designed to investigate the sorption characteristics of binary mixtures of NaCl and sucrose or glucose stored at various relative humidities ranging from 46% to 92%. At low relative humidity below RH 65%, the sorption equilibrium was easily achieved, whereas at higher relative humidity values over 73%, all of the mixtures tended to cintinously absorb moisture with increase in storage time. A linear equation of log $({\frac{dw}{dt}})$ = a log(t) + log(b) was found to be valid between the sorption rate and storage time with respect to storage humidities. In sucrose-NaCl mixture, the slope showed a increasing tendency as the percentage of NaCl increased in the mixture, while that of glucose-NaCl mixture failed to show a definite trend. Plateaus were obtained when the amount of water absorbed was plotted on the X axis and the percent composition of mixture on the Y axis at different storage time. The shape of plateau was varied with respect to the kind of sugar-NaCl mixture, composition of the mixture and relative humidities. A linearity was found between log(1-Aw) and the amount of water absorbed over the Aw range 0.73-0.92 and the slope was affected by the kind and composition of sugar-NaCl mixtures.

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