Abstract Research on biodegradable films is a topic of strategical interest in the field of food science and technology. These films are membranes conformed by biopolymers that interact strongly with water and they generally require the addition of plasticizer in order to improve its integrity and mechanical properties. The study of the hydration and water transfer properties through these films, as well as understanding in what way the thickness and the addition of the plasticizer affect these properties, is essential for a better knowledge and optimization of the required protective function of these membranes. In this work the hydration kinetics and water transport through biodegradable films obtained from yeast biomass were studied, in order to know the performance against changes in thickness and glycerol content. Hydration kinetics experiments allowed obtaining solubility of water in the matrix film, and the diffusion coefficient. Results demonstrated that when glycerol content was increased, the solubility of water increased while diffusion remained constant. Moreover, when the film thickness was grown, the solubility of water decreased but the diffusion increased. Experimental water vapour permeability obtained through traditional cup method was compared to the theoretical permeability calculated by multiplying diffusion coefficient and water solubility. The good agreement observed between both values allowed the analysis of how solubility and diffusion contributed to permeability. As a result this study revealed that the increment of permeability with the plasticizer content was due to the increase in solubility, while the effect of the thickness increasing permeability was dominated by diffusion.

中文翻译：

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基于酵母生物质的薄膜中的水合作用和水蒸气传输特性：增塑剂含量和厚度影响的研究

摘要 生物降解薄膜的研究是食品科学与技术领域具有战略意义的课题。这些薄膜是由与水强烈相互作用的生物聚合物构成的膜，它们通常需要添加增塑剂以提高其完整性和机械性能。研究通过这些薄膜的水合作用和水转移特性，以及了解增塑剂的厚度和添加以何种方式影响这些特性，对于更好地了解和优化这些膜所需的保护功能至关重要。在这项工作中，研究了通过从酵母生物质获得的可生物降解薄膜的水合动力学和水传输，以了解对厚度和甘油含量变化的性能。水合动力学实验允许获得水在基质膜中的溶解度和扩散系数。结果表明，当甘油含量增加时，水的溶解度增加，而扩散保持不变。此外，随着薄膜厚度的增加，水的溶解度降低，但扩散增加。将通过传统杯法获得的实验水蒸气渗透率与通过乘以扩散系数和水溶性计算得出的理论渗透率进行比较。两个值之间观察到的良好一致性允许分析溶解度和扩散如何影响渗透性。结果表明，随着增塑剂含量的增加，渗透率的增加是由于溶解度的增加，