Proton NMR transverse relaxation measurements to study water dynamic states and age-related changes in Mozzarella di Bufala Campana cheese

Proton transverse magnetization decay curves of Mozzarella di Bufala Campana samples were measured and analysed for the presence in the sample of four components, namely “serum water”, “entrapped water”, “junction zone water” and “fat”, characterised by different transverse relaxation times, T₂. T₂ values were interpreted on the basis of the diffusive and chemical exchange model that allowed information to be obtained on the size of diffusive domains and dynamics of the water molecules. Furthermore, T₂ values were measured as a function of the aging time of Mozzarella samples, as produced by different cheese-makers. A decrease of “serum water” T₂ value with aging time was found and this may be used to monitor the evolution of Mozzarella samples up to seven days after manufacture.