Fatty acids, vitamins and minerals in milk are important for the human consumer, the calf and the cow. Studies indicate that milk from organic and conventional dairy herds may differ in these aspects. The aim of this study was therefore to investigate whether there are differences in the fatty acid composition and concentration of vitamins and selenium in milk between organic and conventional herds in Sweden. Bulk tank milk was sampled in 18 organic and 19 conventional dairy herds on three occasions during the indoor season 2005–2006. Herd characteristics were collected by questionnaires and from the official milk recording scheme. Multivariable linear mixed models were used to evaluate the associations between milk composition and type of herd, while adjusting for potential confounders and the repeated observations within herd. In addition to management type, variables included in the initial models were housing type, milk fat content, herd size, average milk yield and time on pasture during summer. The median concentration of conjugated linoleic fatty acids (CLA) was 0·63% in organic compared with 0·48% in conventional herds, the content of total n-3 fatty acids was 1·44% and 1·04% in organic and conventional milk, respectively, and the content of total n-6 fatty acids was 2·72% and 2·20% in organic and conventional milk, respectively. The multivariable regression models indicated significantly higher concentrations of CLA, total n-3 and n-6 fatty acids in organic milk and a more desirable ratio of n-6 to n-3 fatty acids, for the human consumer, in organic milk. The multivariable models did not demonstrate any differences in retinol, α-tocopherol, β-carotene or selenium concentrations between systems. Median concentrations of α-tocopherol were 0·80 μg/ml in organic and 0·88 μg/ml in conventional milk, while for β-carotene the median concentrations were 0·19 and 0·18 μg/ml, respectively; for retinol, the median concentration was 0·32 μg/ml in both groups; the median concentrations of selenium were 13·0 and 13·5 μg/kg, respectively, for organic and conventional systems.

Using actual retail purchases from the 2006 Nielsen Homescan panel data, we estimate a hedonic model on price premiums and discounts associated with household characteristics, market factors, and product attributes focusing on the organic attribute for fluid milk. The organic attribute carries a significant price premium, which is largest of all product attributes considered in this study. Further, additional price variations among organic milk are observed for differences in fat content, container size and branding. Specifically, the results suggest that organic price premiums for half-gallon milk range from $1.23 for whole private label organic milk (60–68% above conventional counterpart) to $1.86 for nonfat/skim-branded organic milk (89–109% above conventional counterpart). The study also found that milk sold in a discount store (i.e., supercenter or club warehouse) was price 13 cents per half gallon, or 7.4%, below milk sold through other venues, and that milk on sale was priced 26 cents per half gallon, or 14.3%, less than the regular average price. Although household characteristics exert little influence on price relative to product attributes and market factors, the study does find that unmarried households and those with children under six pay slightly higher prices for milk, possibly due to time constraints.

Interest in organic dairying is increasing at a rapid pace in California, and the demand for organic milk and dairy products is growing even faster. The intent of this study was to determine the cost of organic milk production, and in particular, to determine the differences in cost of production of organic and conventional milk. Primarily we are interested in whether the differences are due to government-mandated requirements or whether they are the result of optional procedures or personal preferences. Previous studies have indicated that under organic production, the higher net returns observed on organic farming enterprises are due mainly to the lower cost of production. This conclusion is not sustained here. Our results show that the total cost of production on a per cow and a per hundredweight basis is 10–20% higher for organic producers than for conventional producers. While not strongly statistically significant, the differences appear to be due to higher feed costs, higher average labor costs, significantly higher herd replacement costs, and significant transition costs