Proposta di calcolo del "contenuto in carne" secondo la dichiarazione della quantità degli ingredienti (quid - Quantitative Ingredient Declarations) con particolare attenzione alla variabilità della concentrazione proteica delle materie prime carnee

Recent studies have shown that beside fat content (Fo) and connective tissue protein- total meat protein ratio (CTRo), a third factor, the percentage of fat-free total meat protein (PFFo) has also to be included in the QUID calculation. This means that the chemical composition of the meat ingredients should be adjusted to a reference PFFo value (PFFref). The latter one is expediently 22.0. Moreover, for avoiding anomalies and incertitude, the nitrogen-protein conversion factor is to be taken conventionally for 6.25, independently from meat tissue type and the total meat protein content has to be determined by the Kjeldahl method. Consequently, it should also be accepted by convention that, the raw-meat materials with higher PFFo > PFFref are to be considered, in principle, as containing fat-free protein ‘in excess’ compared to those with PFFo = PFFref. On the other hand, the raw-meat materials with PFFo < PFFref contain ‘surplus’ water compared with PFFo = PFFref. The adjustment signifies a virtual (or real) ‘dilution’ with water (if PFFo > PFFref) or a virtual ‘removal’ of water (if PFFo < PFFref) regarding the meat ingredients. In this way, the calculation scheme will be more complex, however, there are no difficulties in setting up a computer program. As shown in this paper, under restricted conditions, the QUID-calculation can also be performed starting from the proximate composition of the finished product.