Proteolytic Peptides as Molecular Markers of Species' Authenticity in Cheeses

摘要

Different mammalian species usually show differences in the casein sequences. Due to the proteolytic process taking place during cheese production and ageing, caseins from different species can generate homologous but not identical peptides. These peptides can be used as molecular markers in order to determine the animal species from which the milk is provided. In the present work LC/ESI-MS methodologies have been applied for detecting species' specific oligopeptides in different cheeses. Fragment 1-23 of αsl-casein has been used as marker for the use of cow's milk as ingredient in two different types of sheep cheeses ("Pecorino"). In both cheeses the presence of cow-derived caseins was confirmed, albeit in one of them only sheep milk was declared among the ingredients. Fragment 16-25 of p-casein was used in order to confirm the actual use of the declared water buffalo's milk as ingredient in mixed cow-water buffalo "Grana" cheeses.