不同干燥方式对洋葱品质的影响

[目的]探究不同干燥方式对洋葱品质的影响。[方法]利用热风加热、微波加热和微波真空加热对黄皮洋葱进行干燥处理,比较各种干燥方式对洋葱Vc含量、白度和抗氧化活性等指标的影响。[结果]微波干燥和微波真空干燥在0.01水平上极显著提高洋葱中还原型Vc含量,在0.01水平上极显著降低洋葱中脱氢Vc含量,二者间Vc总含量差异达0.01极显著水平,主要因为还原型Vc含量存在0.01极显著差异,脱氢Vc含量差异不显著;微波真空干燥能明显提高洋葱白度;微波干燥和微波真空干燥对洋葱清除O2.-的能力有较好的增强作用,对洋葱清除.OH的能力影响不明显,二者间差异不显著,同时热风干燥温度升高会降低洋葱对O2.-和.OH的清除能力。[结论]该研究为利用微波干燥技术实现脱水洋葱片、洋葱粉的工业化生产提供了参考。

Effects of Different Drying Methods on the Quality of Onion

[Objective] The research aimed to explore the effects of different drying methods on the quality of onion.[Method] Yellow-skinned onion was dried by using the methods of hot-blast heating,microwave heating and microwave vacuum heating to compare the effects of all kinds of drying methods on the indexes such as Vc content,whiteness and antioxidation activity in onion. [Result] The content of reduced Vc content in onion was extremely significantly increased by microwave heating and microwave vacuum heating at 0.01 level and the content of dehydrogenated Vc in onion was extremely significantly decreased at 0.01 level.The difference of the total Vc content between the two reached extremely at significant level(0.01),which was mainly caused by extremely significant difference of reduced Vc content and no significant difference of dehydrogenated Vc content.The whiteness of onion could be obviously increased by microwave vacuum drying.Microwave drying and microwave vacuum drying had better strengthening effects on the cleaning capability of O2.-in onion and had no obvious effect on the cleaning capability of·OH in onion,but there is no significant difference between the two.In the treatment of hot blast drying,the rise of temperature could decrease the cleaning capability of O2.-and ·OH in onion.[Conclusion] The research provided references for realizing the industrialized production of the dehydrated onion tablets and onion powder by using microwave drying technology.