Abstract
Cyclopropane fatty acids (CPFAs) in dairy products are indicators of silage feeding in cows' diet. Since Alpine haymilk production strictly prohibits silage feeding, CPFAs analysis provides a reliable approach to verify the authenticity of haymilk. In this study, commercial yoghurt samples-primarily from Italy and Austria-were analyzed for the detection of CPFAs molecular markers using 1H NMR. The method was validated by GC-MS. The two methods showed a strong correlation in the quantitative detection of the CPFAs (R2 = 9480). 1H NMR detected the CPFAs in all non-haymilk yoghurt samples, as well as in one sample derived from haymilk, with concentrations ranging from 254 to 1174 mg kg-1 of total fat. Moreover, experimental yoghurt samples showed CPFAs contents consistent with those of the starting milk. Overall, 1H NMR represents a rapid and reliable alternative to GC-MS for the detection of CPFAs markers to assess the authenticity of haymilk in yoghurt production and verify compliance with production regulations.