Odorant properties of beef: Chemometric and bioinformatics modeling

The release of volatile compounds through the beef generating the characteristic odors and flavors is part of our daily experience. In current studies with food matrices, the scientific effort was centered on the aroma compounds perceived by consumers, but the information about the biochemistry and metabolic source of these odorants is not totally available. It is well known, that many of these compounds can be produced by maturation changes. However, the beef has volatile compounds before the maturation changes, arising the question: How the meat produces these odorant compounds? The objective was proposing a model to describe odorant properties and volatile compounds released by beef.Volatile compounds of beef (Bos taurus, M. longissimus dorsi) were measured using CG/MS-SPME (Gas Chromatography / Mass Spectrum - Solid Phase Micro Extraction). Compounds identification was performed on the basis of the Mass Spectral MS-library (NIST, USA). A bioinformatics database (KEGG, Japan) was used to reconstruct the volatile metabolism of fresh-meat. Chemometrics approach based on PCA (Principal Component Analysis) was made to modeling the relationship between different odorants.A graph model was made matched odorants identified in beef with compounds described in KEGG database (querying Bos taurus section). Pathways were linked through a central branch mediated by glycolysis. The model indicates that glycolysis likely triggers the release of odorants, such as occurs with the lactate production in rigor-mortis. Chemometric analysis of chromatograms show that volatile profile changes in the rigor-mortis associated to glycolytic activity and pH decreasing. It is very important to understand the odorant properties of beef, because this information could be used to develop technologies to certificate the beef and to enhance the flavor.