【作者】 李青柯；

【导师】 张长利；

【作者基本信息】 东北农业大学 ， 计算机应用， 2003， 硕士

【摘要】 食品加工目的之一是保护与保存食品，杀死其中的微生物等。灭菌是食品加工的必经工序。 食品工业一直采用热处理杀菌消毒，但极大地影响食品色、香、味及营养成份。而新的处理方法存在各自的局限性。脉冲电场可以有效杀灭液体中的细菌。其实际应用须解决3个问题：是否引起新的污染；是否比传统方法有明显的经济优势；实现规模化。 高电压脉冲灭菌与传统的巴氏灭菌法相比有以下优点： 1．灭菌效果好。 2．对食物的营养成分保存效果好。 3．灭菌速度极快。 4．灭菌后易处理。 高电压脉冲发生器的研制是整个试验的关键。我们通过资料的查阅和技术的分析，采用了电容快速充放电的方法来产生高电压脉冲。 本试验研制的高电压脉冲发生器，能产生峰值电压为0—30kV，脉冲宽度在纳秒级的高电压脉冲。同时输出的脉冲频率在0.5—50Hz范围内可调。 用此高电压脉冲发生器对有细菌的牛奶进行了灭菌效果的测定。 脉冲峰值电压为30kV，脉冲频率为50Hz，灭菌腔体电极间隙为3mm。在此条件下对牛奶施加了1分钟的高电压脉冲。将灭菌前后的牛奶进行测定，效果显著。更多还原

【Abstract】 One of the food processing purpose is protecting and keeping food, and killing microorganism in it. Sterilization is a necessary process in food processing.The food industry had adopted the heat sterilization all the time, but it influences food colour, fragrance and taste and nutrition greatly. But the new treatment methods have their own limitation. Pulse electric field can almost kill bacterium of liquid effectively. Its practical application must solve 3 problems: Whether cause new pollution; Whether have obvious economic advantages more than the traditional method; Realize scale.There are the following merits compared with traditional pasteurism in high voltage pulse sterilization:1. Sterilization is effectual.2. Keeping the nutrition of the food effectually3. The speed of sterilization is extremely fast.4. It is easy to deal with after sterilization.The research of the high voltage pulse generator is the key to the test. We consult and analysis of technology through materials, We adopt the method of generating high voltage pulse by charging and discharging capacitance fast after technical analysis and consulting of the materials.The high voltage pulse generator developed in this test can generate high voltage pulse with peak voltage value between 0 and 30 kV and pulse width within 1 s. At the same time the pulse frequency out-putted can be adjustable within the range of 0.5-50Hz.We carry on sterilization survey of result with high voltage generator to milk having bacterium.The voltage of peak value of the pulse is 30 kV, pulse frequency is 50 Hz, the electrode interval of electrode of sterilization chamber is 3 mm. We exerted the high voltage pulse for one minute to the milk under this condition.We mensurate the quantity of bacterium in the milk before and after sterilizing. And the effect is remarkable.更多还原