Background – The potential for agricultural practices to influence the nutritional quality of food has long been debated particularly when comparing foods produced by organic and conventional agricultural methods. Whilst it has been established that different feeds affect the quality of cows' milk, there are relatively few studies that compare the effect of organic agricultural practices on the fatty acid composition of dairy products.
Objectives – To determine the fatty acid composition of dairy products that are available on the Australian market that have been produced through certified organic or conventional agricultural methods.
Design – Sixty two samples of certified organic dairy products [milk, n=11; cheese, n=14; cream, n=6; and yoghurt, n=31]; and 45 conventional samples [milk, n=7; cheese, n=13; cream, n=5; and yoghurt, n=20] were purchased from a range of commercial outlets in Sydney. The samples were homogenised, the lipids were extracted and the fatty acid composition was determined by using gas chromatography.
Outcomes – Small but statistically significant differences were observed in the saturated fatty acid composition, with lower percentages of lauric (2.2 vs 2.4, P<0.05) and myristic (10.1 vs 10.5, P<0.05) acids detected in organic dairy products as compared to their conventional counterpart, respectively. No differences were noted in either the π-3 or π-6 fatty acids between the organic and conventional samples. However, organic cheese was found to have a lower total polyunsaturated fatty acids content (P<0.05), and milk was found to have a higher π-3:π-6 ratio (P<0.05) compared to the matched conventional products.
Conclusion – Dairy products that are produced by organic or conventional methods have small but significant differences in their fatty acid composition. Whilst the decrease in lauric and myristic acids and increase in π-3:π-6 ratio indicate a potentially favourable fatty acids profile in organic products, the magnitude of the differences is small and the observation cannot be applied uniformly to all dairy product categories.