title: Formation of naturally occurring pigments during the production of nitrite-free dry fermented sausages.
abstract: This study investigates the potential of producing red coloured dry fermented sausages without the addition of nitrite and/or nitrate. Therefore, the formation of zinc protoporphyrin IX (Zn(II)PPIX) as naturally occurring pigment, and the interrelated protoporphyrin IX (PPIX) and heme content were evaluated during nitrite-free dry fermented sausage production at different pH conditions. Zn(II)PPIX was only able to form in dry fermented sausages at pH conditions higher than approximately 4.9. Additionally, the presence of Zn(II)PPIX increased drastically at the later phase of the production process (up to day 177), confirming that in addition to pH, time is also a crucial factor for its formation. Similarly, PPIX also accumulated in the meat products at increased pH conditions and production times. In contrast, a breakdown of heme was observed. This breakdown was more gradual and independent of pH and showed no clear relationship with the formed amounts of Zn(II)PPIX and PPIX. A statistically significant relationship between Zn(II)PPIX formation and product redness was established.
authors.affiliation: Research Group for Technology and Quality of Animal Products, Department M(2)S, member of Leuven Food Science and Nutrition Research Centre (LFoRCe), KU Leuven Technology Campus Ghent, Gebroeders De Smetstraat 1, B-9000 Ghent, Belgium; Groupe ISA, Food Quality Laboratory, Boulevard Vauban 48, F-59046 Lille Cedex, France. Electronic address: hannelore.demaere@kuleuven.be.
authors.forename: Hannelore
authors.initials: H
authors.lastname: De Maere
authors.affiliation: Research Group for Technology and Quality of Animal Products, Department M(2)S, member of Leuven Food Science and Nutrition Research Centre (LFoRCe), KU Leuven Technology Campus Ghent, Gebroeders De Smetstraat 1, B-9000 Ghent, Belgium.
authors.forename: Ilse
authors.initials: I
authors.lastname: Fraeye
authors.affiliation: Research Group for Technology and Quality of Animal Products, Department M(2)S, member of Leuven Food Science and Nutrition Research Centre (LFoRCe), KU Leuven Technology Campus Ghent, Gebroeders De Smetstraat 1, B-9000 Ghent, Belgium.
authors.forename: Eveline
authors.initials: E
authors.lastname: De Mey
authors.affiliation: Research Group for Technology and Quality of Animal Products, Department M(2)S, member of Leuven Food Science and Nutrition Research Centre (LFoRCe), KU Leuven Technology Campus Ghent, Gebroeders De Smetstraat 1, B-9000 Ghent, Belgium.
authors.forename: Lore
authors.initials: L
authors.lastname: Dewulf
authors.affiliation: Centre for Food and Microbial Technology, Department M(2)S, member of Leuven Food Science and Nutrition Research Centre (LFoRCe), KU Leuven, Kasteelpark Arenberg 23 box 2457, B-3001 Leuven, Belgium.
authors.forename: Chris
authors.initials: C
authors.lastname: Michiels
authors.affiliation: Research Group for Technology and Quality of Animal Products, Department M(2)S, member of Leuven Food Science and Nutrition Research Centre (LFoRCe), KU Leuven Technology Campus Ghent, Gebroeders De Smetstraat 1, B-9000 Ghent, Belgium.
authors.forename: Hubert
authors.initials: H
authors.lastname: Paelinck
authors.affiliation: Groupe ISA, Food Quality Laboratory, Boulevard Vauban 48, F-59046 Lille Cedex, France.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Chollet
mesh_terms: D000818:Animals; D003116:Color; D005285:Fermentation; D006418:Heme / Q000378:metabolism*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008461:Meat Products / Q000032:analysis*; D009566:Nitrates; D009573:Nitrites; D011524:Protoporphyrins / Q000096:biosynthesis*; D015032:Zinc / Q000378:metabolism*
chemical_list: D009566:Nitrates; D009573:Nitrites; D011524:Protoporphyrins; C017803:zinc protoporphyrin; D006418:Heme; C028025:protoporphyrin IX; D015032:Zinc
keywords: Heme; Natural colouring; Protoporphyrin IX; Zinc protoporphyrin IX; pH condition