Formation of zinc protoporphyrin IX in Parma‐like ham without nitrate or nitrite

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.

Zinc-protoporphyrin content in commercial Parma hams is affected by proteolysis index and marbling

“…Regarding heme content, it can be observed that this pigment was present in lower amounts when compared with that of the ZnPP (Table 1). The reported amounts are also in line with those reported by other authors ranging from 15-29 mg/kg expressed on fresh weight basis (Wakamatsu et al 2009a;De Maere et al 2014;Wakamatsu et al 2009b).…”

“…Various authors have suggested that the direct interchange of zinc with iron in the heme moiety does not occur (Wakamatsu et al 2009b;Becker et al 2012). Therefore, it is important to know the existing relationships between these two main pigments and look for those elements that may influence the ratio between them.…”

“…Therefore, a number of endogenous and exogenous factors that have not yet been completely elucidated could have an effect on the formation of ZnPP in Parma hams (Grossi et al 2014;Paganelli et al 2016). Although several factors affecting ZnPP have been studied in in vitro models, data is scarce on typical ZnPP contents in drycured Parma ham and studies dealing with the factors involved in the formation of this pigment in hams are still necessary (Wakamatsu et al 2009b;Parolari et al 2009;De Maere et al 2014). Therefore, it is important to gain a better understanding of the factors that contribute to this pigment content because they determine the characteristic colour of non-nitrified dry-cured hams.…”

Porcine Ferrochelatase: The Relationship between Iron-Removal Reaction and the Conversion of Heme to Zn-Protoporphyrin

“…Other investigators 26) have reported that the formation of Zn-protoporphyrin in Parma ham significantly increased after a curing time of 40 weeks, in which pig leg was incubated with salt at 1.0-1.5…”

Process-driven bacterial community dynamics are key to cured meat colour formation by coagulase-negative staphylococci via nitrate reductase or nitric oxide synthase activities

“…Other approaches are based on the substitution of the effects of curing agents by other biological substances, as for the use of antimicrobial cherry powder , rosemary extract as a colour-stabilizing antioxidant , or natural colourants such as curcumin, paprika, β-carotene, cochineal, and tomato (Bázan-Lugo et al, 2012). In addition, two promising enzymatic processes are being explored that may offer an alternative for cured colour formation in meat products; namely, the formation of zinc protoporphyrin IX by ferrochelatase or mitochondrial enzymes, as described for Parma ham (Wakamatsu et al, 2009), and the formation of nitrosomyoglobin by meat-associated bacteria with NOS activity (Li et al, 2013).…”