가소제로서 솔비톨 혼합물의 첨가가 분리대두단백 필름의 수분흡습특성, 수분투과도, 색, 인장강도 및 신장률, 그리고 용해 특성에 미치는 영향을 조사하였다. 솔비톨 혼합물은 액상형과 결정형의 상태로 다양한 비율로 혼합하여 첨가하였고, 가소제로 글리세린을 첨가한 대조구 필름의 물리적 특성과 비교하였다. 솔비톨이 첨가된 필름은 대조구 필름에 비해 높은 인장강도를 갖는 반면 낮은 수분투과도 및 신장률을 보였다. 한편 솔비톨 첨가 형태에 따른 영향은 필름
The effects of sorbitol mixture as plasticizers on moisture sorption property (MSP), water vapor permeability (WVP), color, tensile strength (TS), elongation at break (E), and total soluble matter (TSM) of soy protein isolate (SPI) films were investigated. Two different types of sorbitols, aqueous and crystalline, were added to film-forming solutions in various ratios of crystalline to aqueous (0:1, 0.25:0.75, 0.5:0.5, 0.75:0.25, or 1:0, based on weight). In addition, the characteristics of the SPI films plasticized by sorbitol mixtures and glycerin were compared with moisture sorption rate against time. Sorbitol-plasticized films had higher in TS, but lower in WVP and E than the glycerin-plasticized films. However the properties of SPI films did not differ appreciably by the type of sorbitol added to film-forming solutions. To explain the high solubility and low WVP of sorbitol-plasticized films, cumulative amounts of moisture content gained during adsorption and lost during desorption of films were compared between sorbitol and glycerin-plasticized films. The result suggest that use of sorbitol as a plasticizer for preparing SPI films improves moisture barrier properties of the films. However the high solubility of sorbitol-plasticized films needs to be reduced for improving the functionality of SPI films in potential packaging applications.