Proteomic analysis of duck fatty liver during post-mortem storage related to the variability of fat loss during cooking of "foie gras".

TitleProteomic analysis of duck fatty liver during post-mortem storage related to the variability of fat loss during cooking of "foie gras".
Publication TypeJournal Article
Year of Publication2013
AuthorsTheron, L, Fernandez, X, Marty-Gasset, N, Chambon, C, Viala, D, Pichereaux, C, Rossignol, M, Astruc, T, Molette, C
JournalJ Agric Food Chem
Volume61
Issue4
Pagination920-30
Date Published2013 Jan 30
ISSN1520-5118
KeywordsAnimals, Breeding, Cold Temperature, Cooking, Diet, Dietary Fats, Ducks, Food Handling, Liver, Meat, Proteins, Proteolysis, Proteomics, Solubility
Abstract

Fat loss during cooking of duck "foie gras" is the main problem for both manufacturers and consumers. Despite the efforts of the processing industry to control fat loss, the variability of fatty liver cooking yields remains high and uncontrolled. To understand the biochemical effects of postslaughter processing on fat loss during cooking, this study characterizes for the first time the protein expression of fatty liver during chilling using a proteomic approach. For this purpose the proteins were separated according to their solubility: the protein fraction soluble in a buffer of low ionic strength (S) and the protein fraction insoluble in the same buffer (IS). Two-dimensional electrophoresis was used to analyze the S fraction and mass spectrometry for the identification of spots of interest. This analysis revealed 36 (21 identified proteins) and 34 (26 identified proteins) spots of interests in the low-fat-loss and high-fat-loss groups, respectively. The expression of proteins was lower after chilling, which revealed a suppressive effect of chilling on biological processes. The shot-gun strategy was used to analyze the IS fraction, with the identification of all the proteins by mass spectrometry. This allowed identification of 554 and 562 proteins in the low-fat-loss and high-fat-loss groups, respectively. Among these proteins, only the proteins that were up-regulated in the high-fat-loss group were significant (p value = 3.17 × 10(-3)) and corresponded to protein from the cytoskeleton and its associated proteins. Taken together, these results suggest that the variability of technological yield observed in processing plants could be explained by different aging states of fatty livers during chilling, most likely associated with different proteolytic patterns.

DOI10.1021/jf302979q
Alternate JournalJ. Agric. Food Chem.
PubMed ID23234381