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Updated: May 23, 2026

Measurement of Tissue Non-Heme Iron Content using a Bathophenanthroline-Based Colorimetric Assay
Published on: January 31, 2022
Effects of illumination and packaging on non-heme iron and color attributes of sliced ham
1Key Lab of Meat Processing and Quality Control, Ministry of Education, Key Lab of Animal Products Processing, Ministry of Agriculture, College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China.
Abstract:
This study was designed to investigate effects of illumination and packaging on color of cooked cured sliced ham during refrigeration, and the possibility of decomposition of nitrosylheme under light and oxygen exposure. Three illumination levels and three packaging films with different oxygen transmission rates (OTRs) were used in two separate experiments during 35 days storage, and pH value, a* value, nitrosylheme, residual nitrite and non-heme iron were evaluated. Packaging OTRs had significant effects (P<0.01) on a* value, but illumination level and packaging OTR did not affect (P>0.05) nitrosylheme concentration during storage. For both groups, storage time had a significant effect (P<0.01) on a* value and nitrosylheme. Negative relationships between nitrosylheme and nitrite in the illumination group, and between nitrosylheme and non-heme iron in the packaging group were observed. Therefore, illumination level and packaging OTR had limited effects on overall pigment stability, but more discoloration and loss of redness occurred on the surface of products.
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