Background – There is increasing evidence that milk contains a range of lipids that can promote health. In Australia, seasonal variation in the nutritive characteristics of pasture is likely to be associated with seasonal variation in the concentrations of lipids in milk.
Objective – To determine if there is seasonal variation in the concentrations of some milk lipids (table) that may be associated with health benefits in humans.
Design – Samples representative of the milk supply from northern Victoria for mid autumn (April), mid winter (July), mid spring (October) and mid summer (January) were analysed for concentrations of milk lipids (g component/kg milk fat). Values with a subscript in common are not significantly different (P<0.05).
Outcomes – The range in values observed for all components was large with maximum values being a whole number multiple of minimum values. The average concentrations of all components examined, with the exception of sphingomyelin, varied with season.
Conclusion – Environmental factors (farm management and season) are important determinants of the concentrations of some lipids in milk produced in northern Victoria. Milk produced in pasture-based production systems should not be considered as a uniform product across seasons.