Butter production from ozone-treated cream: Effects on characteristics of physicochemical, microbiological, thermal and oxidative stability

The goal of this research was to investigate the effects of the ozone treatment (OT) to raw cream on the physicochemical, microbiological, thermal, and oxidative properties of butter. For this purpose, butter samples were produced from raw cream, which was ozone-treated for 5 (OT-5), 15 (OT-15), 30 (OT-30), and 60 (OT-60) min. The control sample was also produced from non-ozonated raw cream. OT increased firmness, consistency, and fat particle size values of cream. The firmness of butter was between 97 and 380 N. Average fat particle size of samples (D[3.2]) ranged from 22.1 to 30.2 mu m, in which OT decreased it. A monomodal fat particle size distribution was determined in all-butter samples. OT decreased b value (yellowness) of butter, and the lowest value was determined in OT-60. The induction time of butter changed from 1.04 (OT-60) - 32.9 h (control). Two melting peaks were determined in butter samples at 14.2-14.6 and 32.3-33 degrees C. Ozonation for 60 min caused 2.01 log reduction in Staphylococci. Above 15 min, OT completely inactivated Salmonella and yeast-mould. Coliform was not detected in OT-30 and OT-60. The results showed that OT resulted in higher microbiological quality in butter from raw cream.