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Updated: May 23, 2026

Synthesis and Characterization of Functionalized Metal-organic Frameworks
Published on: September 5, 2014
Formation of zinc protoporphyrin IX in Parma-like ham without nitrate or nitrite
Jun-ichi Wakamatsu1, Juichi Uemura, Hiroko Odagiri
1Research Faculty of Agriculture, Hokkaido University, Kita, Sapporo, Hokkaido, Japan. jwaka@anim.agr.hokudai.ac.jp
Abstract:
Zinc protoporphyrin IX (ZPP) is a characteristic red pigment in meat products that are manufactured without the addition of a curing agent such as nitrate or nitrite. To examine the effects of impurities such as mineral components in sea salt on the formation of ZPP, we manufactured Parmatype dry-cured hams that were salted with refined salt or sea salt and examined the involvement of oxidation-reduction potential (ORP) in the formation of ZPP. The content of ZPP was increased drastically after 40 weeks. Microscopic observation showed strong fluorescence caused by ZPP muscle fiber after 40 weeks. Conversely, heme content varied considerably during processing. ORP increased during processing. However, there was no obvious difference between ham salted with refined salt and that salted with sea salt. Therefore, it was concluded that impurities in sea salt were not involved in the formation of ZPP.
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