变温压差膨化干燥对冬枣总黄酮和水溶性糖含量的影响

研究了变温压差膨化干燥对冬枣中总黄酮和水溶性糖含量的影响。比较了超声波-微波辅助乙醇法和乙醇法提取冬枣总黄酮的效果,采用水提法提取冬枣中水溶性糖,参照Fenton法比较了膨化前后冬枣黄酮的清除羟基自由基能力,采用Sehpadex G-150凝胶层析法测定冬枣水溶性糖分子量分布。结果表明:微波-超声波辅助乙醇法提取总黄酮优于乙醇法。冬枣在膨化前后总黄酮和水溶性糖含量发生了显著的变化。冬枣鲜果、预干燥冬枣和膨化冬枣中黄酮含量分别为1.59%、0.71%、0.38%,膨化冬枣清除羟基自由基能力较冬枣鲜果下降。冬枣鲜果、预干燥冬枣和膨化冬枣中水溶性总糖分别为45.23%、55.84%、44.34%,还原糖分别为38.91%、47.29%、38.56%。Sehpadex G-150凝胶层析结果表明,冬枣鲜果中含有较多的大分子多糖,而膨化枣中含有较多的小分子糖。

Effects of Explosion Puffing Drying at Modified Temperature and Pressure on Total Flavonoids and Water Soluble Saccharides of Winter Jujube(Zizyphus jujube Mill)

Effects of explosion puffing drying at modified temperature and pressure on total flavonoids and water soluble saccharides of winter jujube(Zizyphus jujube Mill) were studied in this paper.The total flavonoids extraction methods(alcohol assisted by ultrasonic wave-microwave and alcohol)were compared.Water soluble saccharides were extracted by hot water.The ability of eliminated the hydroxyl free radical of total flavonoids from puffing and un-puffing winter jujube was compared according to Fenton method.Water soluble saccharides was isolated by Sehpadex G-150 gel filtration.The results showed that the flavonoids extracted by alcohol assisted by ultrasonic wave-microwave was superior to that extracted by alcohol.The contents of total flavonoids and water soluble saccharides of winter jujube changed obviously during the explosion puffing drying.The total flavonoids content of fresh fruit,pre-dry and puffing dry winter jujube were 1.59%,0.71%,0.38% respectively.Ability of eliminated the hydroxyl free radical of puffing dry winter jujube was lower than that of fresh winter jujube.Water soluble saccharides and reduce sugar contents of fresh fruit,pre-dry and puffing dry winter jujube were 45.23%,55.84%,44.34% and 38.91%,47.29%,38.56%,respectively.There were more high molecule saccharides in fresh winter jujube fruits and more low molecule saccharides in puffing dry winter jujube by Sehpadex G-150 gel filtration showed.