Identification of physical properties and volatile and non-volatile compounds for discrimination between different Emmental-type cheeses: a preliminary study

Abstract

Differentiation between Emmental cheese produced in diverse regions is of major interest to verify product authenticity and avoid product imitation. The objective of this study was to identify parameters that allow a differentiation between Southern German Emmental cheese and Emmental cheese produced in other regions based on physical properties and volatile and non-volatile compounds. Emmental cheese samples were collected from seven German dairies located in Bavaria and Baden-Wuerttemberg (regional Emmental cheese). Additionally, generic Emmental cheeses produced in Northern Germany, the Netherlands and Poland (European Emmental cheese) were added to the data set as well as Swiss Emmental and Allgau Emmental cheeses. A large variety of characteristics was previously analysed by application of thermo-rheological methods and targeted quantification methods (e.g. GC-MS and dynamic oscillatory shear measurement). Stepwise discriminant analysis was used to identify parameters with high discriminant power. These were brightness L*, loss modulus G″ at 20 °C, loss factor tan δ max, 3-methylbutyric acid, acetic acid, propionic acid, γ-Glu-Leu, γ-Glu-Val and the peptide Ile-Val-Pro-Asn. The data set resulting from the nine parameters was subjected to linear discriminant analysis followed by a cross validation step. Regional Emmental cheese was classified correctly at 95%, whereas 75% of European Emmental cheese and 100% of Swiss and Allgau Emmental cheeses were correctly classified. The results are preliminary but may provide, upon further verification, a useful tool for cheese makers to identify Emmental cheese produced in different regions based on a small number of characteristic parameters and prevent product imitation.