Composition and properties of bovine milk: A study from dairy farms in northern Sweden; Part II. Effect of monthly variation

This study investigated the influence of monthly variation on composition and properties raw farm milk collected as part a full-scale cheese-making trial in region northern Sweden. In our companion paper, contribution on-farm factors to quality attributes is described. total, 42 dairy farms were recruited for study, samples over 1 yr characterized importance cheese making. Principal component analysis suggested that during outdoor period (June–September) different from indoor period. Despite interaction with milking system, results showed fat protein concentrations lower May through August, lactose concentration was higher April July than other months. Concentrations free fatty acids generally low, highest value (0.86 mmol/100 g fat) observed February lowest (0.70 June. Plasmin plasminogen-derived activities varied sampling month without clear seasonal pattern. The pH tank ranged 6.60 6.82, values September February, respectively. somatic cell count August (201 × 103 cells/mL) (143 cells/mL). gel strength, recorded December (88 Pa) (64 Pa). Rennet coagulation time strength inversely correlated, rennet December. Orthogonal projections latent structures (OPLS) discriminant adaptation OPLS identified casein micelle size total proteolysis major responses month, smaller associated Using further investigate causes behind traits revealed there addition feeding pasture differed between Because fresh grass seldom primary feed period, grazing not considered sole reason difference periods attributes.