Influence of dairy production systems on milk fatty acid and mineral profiles

Introduction: In recent years, there has been a diversification of dairy production systems, with the emergence of practices such as robotic milking, pasture-based milk, and organic production. The objective of this study is to evaluate how different dairy production systems affect the fatty acid and mineral profiles of milk.

Methods: A total of 40 bulk tank milk samples were collected from four production systems: conventional intensive (n=10), intensive with robotic milking (n=10), pasture-based (n=10), and organic. Fatty acid profiles were analyzed using GC-FID, while mineral content (Na, Ca, K, P, Mg, and I) was determined by ICP-MS. Statistical analysis was performed using R (version 4.4.2), employing ANOVA combined with Fisher’s LSD test for multiple comparisons.

Results: Significant differences were observed in the fatty acid profiles among the different production systems. Oleic acid levels were significantly lower (p < 0.05) in milk from intensive systems, while linoleic acid levels were significantly lower in pasture-based milk (p < 0.05). Conversely, levels of linolenic acid and eicosenoic acid were significantly higher (p < 0.05) in organic milk. Although not statistically significant, the atherogenic index was higher in milk from intensive systems compared to the other production types, particularly when compared to pasture-based systems. Regarding minerals, sodium levels were significantly higher (p < 0.05) in organic (364.51±38.73 mg/kg) and pasture-based milk (360.42±25.87 mg/kg). Phosphorus levels were lower in pasture-based milk (945.09±47.92 mg/kg) compared to milk from intensive systems (991.95±58.56 mg/kg). Iodine levels were significantly lower in organic (0.07±0.04 mg/kg) and pasture-based production (0.10±0.04 mg/kg).

Conclusion: The type of dairy production systems has a clear impact on the nutritional profile of milk. Identifying the optimal production conditions to achieve the best nutritional profile may help improve consumer health.