...
【24h】

WATER ACTIVITY AND VISCOSITY - RELATIONS WITH GLASS TRANSITION TEMPERATURES IN MODEL FOOD SYSTEMS

机译:模型食品系统中水的活度和粘度-与玻璃转变温度的关系。

获取原文
获取原文并翻译 | 示例
           

摘要

Both thermodynamic and kinetic parameters are important in food processing and stability. Thermodynamic parameters are represented by water activity and generally applied to high and medium moisture content materials, where molecules can freely diffuse, without restrictions. In contrast, kinetic properties mainly apply to intermediate and low moisture content foods, where diffusional mobility of reactants is more or less restricted and where water acts as a plasticizer of amorphous compounds. Kinetic properties can be represented by viscosity and related to the glass transition temperature (T-g) by the Williams-Landel-Ferry equation. Thus, in a food system passing From high to intermediate and low moisture content and/or from high to low temperature, the prevailing control mechanism will gradually change from thermodynamic to kinetic. The relationship between the water activity, temperature and viscosity is presented for some model solutions. [References: 14]
机译:热力学参数和动力学参数对食品加工和稳定性都很重要。热力学参数以水活度表示,通常适用于水分含量高和中等的材料,分子可以不受限制地自由扩散。相反,动力学特性主要适用于中水分含量低的食品,其中反应物的扩散迁移或多或少受到限制,并且水充当无定形化合物的增塑剂。动力学特性可以用粘度表示,并可以通过Williams-Landel-Ferry方程与玻璃化转变温度(T-g)相关。因此,在食品中水分含量从高到中,低和/或从高温到低温的过程中,主要的控制机制将从热力学逐渐转变为动力学。给出了一些模型解中水活度,温度和粘度之间的关系。 [参考:14]

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号