期刊论文

He, X.(hedevid@163.com)

中文

农业工程学报

1002-6819

2013

29

17

279-285

10.3969/j.issn.1002-6819.2013.17.036

天津市农业科技合作项目（07050309）；

本校为其他机构

为探究冻融处理对甘薯变温压差膨化干燥产品品质影响的机理,应用低场核磁共振技术(low-field nuclear magnetic resonance,LF-NMR)研究了冻融后甘薯中水分存在形式和各组分含量,比较了冻融次数对甘薯膨化干燥产品硬度、色泽和多孔性等品质指标的影响。结果表明:冻融后甘薯LF-NMR自旋-自旋弛豫时间T_2谱中出现4个水分峰,其横向弛豫时间分别为T_(21)(0.25~0.55 ms)、T_(22)(1~2.5 ms)、T_(23)(5~12 ms)、T_(24)(40~200 ms)。随着冻融次数增加,自由水含量(mT_(24))先增加后减少,结合最紧密的水含量(mT_(21))先减少后增加;干燥产品多孔性和复水性逐渐增大,ΔE逐渐变小,L~*和硬度先减小后有稍许增大。...

The water content is generally 70% to 90% in fresh fruits and vegetable, which usually includes free water, immobilized water, and closely combined water. The water content and its distribution in the raw materials of fruit and vegetable may affect the drying process, physicochemical, and sensory characteristics of dry products dried by different drying technologies. There are a lot of drying methods reported, such as natural sun drying, vacuum drying, heat pump drying, forced-air drying, microwave drying, convective drying, freeze-drying, and explosion puffing drying. Nuclear magnetic resonan...