
Depending on regional differences, zongzi vary in shape and ingredients. Most contain sweet glutinous short grain rice and bamboo leaves, other typical ingredients include dates, sweetened red bean paste, dried sausage, cured pork belly, chestnuts, lotus seeds, and salted egg yolk. In southern China, salty zongzi with meat and complementary savoury items tend to be common while in northern China sweet bean paste or date filled zongzi are the custom. However, you can pretty much use any combination of ingredients you like as long as they take well to long, slow cooking.
Common Ingredients for zongzi
Bamboo leaves, Zong ye
Sweet glutinous short grain rice, Nuo mi
Guangdong style sweet sausage, Xiang chang
Smoked cured pork, La rou
Cured fatty side pork, Fei la rou
Dried peanuts, Hua sheng
Mung beans, Lu dou
Millet, Xiao mi
Red beans, Hong xiao dou
Dried shrimp, Hai mi
Salted duck egg yolk, Xian ya dan
Dried lotus seeds, Lian zi
Dried red dates, Wu he zao
http://www.zhongguoonline.com/post/Zongzi.html