The respective EU directive introduces, in accordance with the quantitative ingredient declaration (QUID), a new definition of 'meat' for the purpose of labelling of products. In addition, it involves maximum numerical limits for fat content and connective tissue protein-total protein ratio depending on the species of meat. The present paper discusses the new concept of meat equivalent, indicated as QUID 1, which, contrary to the definition of 'meat content' (QUID1r) in the respective regulation, may exceed 100%, indicating high quality meats with lower fat and connective tissue content than the maximum limits. Moreover, the meat equivalent (QUID1) is also an intermediary step in the QUID calculations. Results are also compared with the existing calculation methods published in the literature. A possible introduction of the unequivocal meat equivalent concept (QUID1) in practice is also discussed in this paper. The presented QUID calculation method postulates the equality of the fat free, 'pure' muscular and connective tissue protein content. As might be expected, the fat-free nitrogen contents published in the scientific literature show appreciable differences in this respect, however, owing to the unstable nitrogen-protein conversion factors for connective tissue proteins, the definition of 'protein content' is contestable. The QUID declaration requires chemical compositional data (fat, connective tissue protein and total protein content) as accurate as possible. The steady analytical control of each raw material is in the majority of cases practically unrealizable. So, the standardization of raw materials has an outstanding importance here. (c) 2005 Elsevier Ltd. All rights reserved.