ass日本风韵熟妇pics男人扒开女人屁屁桶到爽|扒开胸露出奶头亲吻视频|邻居少妇的诱惑|人人妻在线播放|日日摸夜夜摸狠狠摸婷婷|制服 丝袜 人妻|激情熟妇中文字幕|看黄色欧美特一级|日本av人妻系列|高潮对白av,丰满岳妇乱熟妇之荡,日本丰满熟妇乱又伦,日韩欧美一区二区三区在线

In order to decrease the freeze-drying time and reduce the process energy consumption, frozen coffee materials with prefabricated porosity were prepared and freeze-dried to explore its influence on freeze-drying experimentally. Instant coffee was selected as the solute in aqueous solution. Results showed that freeze-drying can be remarkably enhanced with the initially unsaturated frozen material compared with the traditionally saturated one. SEM images of dried products revealed that the initial unsaturated material had the spherical and uniformed porous structure, which was favorable to migration of sublimated vapor and improvement of the drying rate. Chamber pressure, which was ranged from 11Pa to 33Pa, had little effect on the freeze-drying process and increasing ambient temperature can be beneficial to the freeze-drying process. Combined heating can significantly reduce the drying time further. When the temperature was above 45℃, the saturated material was found to collapse causing the failure of freeze-drying. In contrast, the unsaturated one can bear higher operation temperature resulting in a relatively high drying efficiency. The conventionally saturated material experiences the raising rate stage, constant rate stage and falling rate stage during freeze-drying, while the unsaturated material was always in the falling rate stage throughout the process. Freeze-drying of initially unsaturated material would impose significant effect on the traditional freeze-drying process of agricultural products.