Abstract: Xuanwei Ham is a famous ham in China with some white particle spots often appeared in ham,mostly in ham muscle. However,examined by microbiological methods and observed by light microscope,there are neither microbes nor parasites in the white particle spots.Proteins in panicles would decompose significantly,and two main proteins with molecular weights of respectively 51000 and 13200 were detected by gradient SDS-PAGE in particles.The content of tyrosine in white particles was eight times higher than that in normal ham muscle,which indicated that the particles might be decomposed protein,tyrosine and some other component.All the contents of inorganic elements analyzed are less than those in ham muscle,and the schondroitin sulfate occurred in white particle implie that pathological disease might occur in muscle at the particle position during five stage of pig.Inoculating yeast on ham during salting can prevent the formation of particles effectively.

Key words: Xuanwei Ham, white particles, tyrosine, component