SEASONAL RELATED CHANGES IN THE MAJOR NUTRIENTS OF BOVINE MILK (TOTAL PROTEIN, LACTOSE, CASEIN, TOTAL FAT AND DRY MATTER)
Augusta Lujerdean, Andrea Bunea, Vioara Miresan
The objective of this study was to analyse the chemical composition of cow milk for an entire year to provide fundamental information for dairy products making and milk cheese yielding. So an investigation of seasonal changes of major nutrients of dairy milk was performed over 12 months beginning in January 2007. Samples were collected weekly from bulk milk shipment in a commercial dairy products company and analyzed for content (%) of total protein, fat, casein, lactose and dry matter. The parameters determined were of interest both from a nutritive and technological point of view. The mean protein content was 3,21±0,10%, lactose 4,87±0,08%, the fat content 3,58±0,07%, casein 2,58±0,10% and dry matter 12,20±0,11%. The relationship of these parameters to season was assessed. The highest and lowest values were observed during winter and summer months respectively.
Key words: cow milk, nutrients, total protein, casein, lactose, fat, dry matter