کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
224971 | 464468 | 2007 | 7 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Water vapor permeability of edible starch based films Water vapor permeability of edible starch based films](/preview/png/224971.png)
Water transport in edible films of starch based products is a complex phenomenon due to the strong interaction of sorbed water molecules with polymeric structure of starch. Water sorption isotherms on high amylose starch based films are highly non linear in the range studied (5–45 °C). So permeability is usually affected by a number of parameters such as temperature, film thickness and plasticizer content. This knowledge is required to simulate and predict transport patterns. In the present contribution water vapor permeability (WVP) of high amylose corn starch (HACS) films, prepared in our laboratory, was determined following ASTM E-96 procedure. WVP increases as temperature increases between 5 and 40 °C and observed results can be correlated with an Arrhenius-type expression. Activation energy of WVP for the starch film investigated is 5.61 kJ/mol and values of WVP ranged between 2 × 10−10 and 1 × 10−9 g m−1 s−1 Pa−1. It is also shown a direct relation between WVP with plasticizer content and film thickness. These observations could be explained in terms of variations in the number of potential intermolecular interactions in the film structure.
Journal: Journal of Food Engineering - Volume 80, Issue 3, June 2007, Pages 972–978