Abstract: The effect of popcorn dipped in different liquors such as moisture salt water and alcohol on microwave vacunm popping was studied in this paper according to the index of the volume expansion ratio．It was found that the moisture content of popcorn was one of the primary factors to affect the volume expansion ratio．Under the microwave vacuum condition‚the optimum popping effect occurs when the moisture content was11．3％ with vacuum26．66kPa and20．4％ with vacuum93．3kPa；Popcorn which is soaked in10％ （mass fraction） salt solution and in40％ alcohol solution respectively could obtain optimum microwave vacuum popping effect． 

Key words: popcorn, dip, microwave vacuum, popping