@article{KhozroughiKrohSchlueteretal.2018,
  author    = {Khozroughi, Amin Ghadiri and Kroh, Lothar W. and Schlueter, Oliver and Rawel, Harshadrai Manilal},
  title     = {Assessment of the bacterial impact on the post-mortem formation of zinc protoporphyrin IX in pork meat},
  series = {Food chemistry},
  volume    = {256},
  journal   = {Food chemistry},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0308-8146},
  doi       = {10.1016/j.foodchem.2018.01.045},
  pages     = {25 -- 30},
  year      = {2018},
  abstract  = {The post-mortem accumulation of the heme biosynthesis metabolite zinc protoporphyrin IX (ZnPP) in porcine muscle is associated with both a meat-inherent and a bacterial enzymatic reaction during meat storage. To estimate the bacterial impact on ZnPP formation, meat and meat-like media were investigated by HPLC-FLD (and MALDI-TOF-MS) after inoculation with a representative microorganism (P. fluorescens). Results indicate the principal ability of meat-inherent bacteria to form ZnPP in meat extracts and meat-like media, but not on the meat muscle. Thus it was concluded that the ZnPP formation in meat is due to a meat-inherent enzymatic reaction induced by porcine ferrochelatase (FECH), while the bacterial (FECH) induced reaction seems to be not significant.},
  language  = {en}
}
@article{KhozroughiJanderSchirrmannetal.2017,
  author    = {Khozroughi, Amin Ghadiri and Jander, Elisabeth and Schirrmann, Michael and Rawel, Harshadrai Manilal and Kroh, Lothar W. and Schlueter, Oliver},
  title     = {The role of myoglobin degradation in the formation of zinc protoporphyrin IX in the longissimus lumborum of pork},
  series = {LWT - food science and technology : an official journal of the Swiss Society of Food Science and Technology (SGLWT/SOSSTA) and the International Union of Food Science and Technology (IUFoST)},
  volume    = {85},
  journal   = {LWT - food science and technology : an official journal of the Swiss Society of Food Science and Technology (SGLWT/SOSSTA) and the International Union of Food Science and Technology (IUFoST)},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0023-6438},
  doi       = {10.1016/j.lwt.2017.06.047},
  pages     = {22 -- 27},
  year      = {2017},
  abstract  = {Investigations on the post mortal formation of fluorescent zinc protoporphyrin (ZnPP) IX in pork meat are currently in focus of meat science research. The role of myoglobin degradation in this context appears to be one of the most diversely discussed issues. To address this question meat-extracts of longissimus lumborum (LL) muscle (0.8 mg/mL) were incubated at 30 degrees C for up to 72 h and investigated by HPSEC-UV-fluorescence, SDS-PAGE and MALDI-TOF-MS. Between 0 and 72 h of incubation the fluorescence intensity (lambda(ex)./(em). = 420/590 nm) of the meat-extracts rose significantly (p < 0.001) from 10.9 +/- 0.8 to 34.8 +/- 0.3 (rel. units) while the staining intensity of the SDS-PAGE of myoglobin non-significantly (p > 0.4) changed from 6.2 +/- 0.5 x 105 to 5.0 +/- 0.3 x 105 (rel. units). The results indicate that ZnPP is formed by a Fe(II)-Zn(II)-substitution in myoglobin heme where an accompanying myoglobin degradation is not necessarily obligatory. (C) 2017 Elsevier Ltd. All rights reserved.},
  language  = {en}
}
@article{MaederRawelKroh2009,
  author    = {Maeder, Jens and Rawel, Harshadrai Manilal and Kroh, Lothar W.},
  title     = {Composition of phenolic compounds and glycoalkaloids alpha-solanine and alpha-chaconine during commercial potato processing},
  issn      = {0021-8561},
  doi       = {10.1021/Jf901066k},
  year      = {2009},
  abstract  = {The influence of a commercial production process for dehydrated potato flakes on the content of free phenolic compounds, total phenolics, and glycoalkaloids in potatoes during the subsequent processing steps was determined. Processing byproducts, such as potato peel (steam peeling), mashed potato residues, and side streams (blanching and cooking waters), have also been investigated. A high-performance liquid chromatography (HPLC) method was developed to separate and quantify caffeic acid, gallic acid, ferulic acid, p-coumaric acid, p-hydoxybenzoic acid, protocatechuic acid, vanillic acid, catechin, and three isomers of caffeoylquinic acid: chlorogenic, neochlorogenic and cryptochlorogenic acid. Determination of the glycoalkaloids a-solanine and alpha-chaconine was performed by using a high- performance thin-layer chromatography (HPTLC) method. The deliverables reveal that processing potatoes to potato flakes remarkably diminishes the content of the analyzed compounds, mainly due to peeling and leaching. The influence of thermal exposure is less significant. About 43\% of the initial phenolic acids and 10\% of the glycoalkaloids remain after processing. The results of the total phenolic content assay by Folin-Ciocalteu reagent are proportional to the content of phenolic compounds determined by HPLC. Steam peeling has a higher influence on glycoalkaloid losses compared to that on phenolics. The highest amounts of phenolic compounds and glycoalkaloids were found in peeling byproduct. During processing, the amount of chlorogenic acid decreased, whereas the concentration of neochlorogenic acid increased due to isomerization. The impact of the results on potato processing technology is discussed.},
  language  = {en}
}