Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 3/2/2015
Publication Date: 3/11/2015
Citation: Van Hekken, D.L., Tunick, M.H., Tomasula, P.M. 2015. Advantages of pasture-based milk products (abstract). Northeast Pasture Consortium annual meeting. Final Program and Abstracts. 1:12.
Technical Abstract: Recent research has focused on determining the biologically active compounds naturally occurring in milk from pasture-fed cows and evaluating the impact of processing on these compounds. This research addresses one of the critical goals of the Northeast Pasture Consortium to “summarize conjugated linoleic acid (CLA) and human nutritional benefits present in grass-fed products”. Dairy products contain many biologically active compounds that can influence human health including the long-chain unsaturated fatty acids (FAs) such as CLA and omega-3 FAs; these are FAs contain 18 carbons and double bonds. Because these healthy lipids have been linked to human health benefits, research to quantify these levels in milk produced using different farming systems is needed. In our 3-year case study comparing milk from adjacent grass-fed organic and confined conventional dairies (minimizing regional and weather-related variations), we showed that the healthy lipids found in the milkfat were significantly higher in the milk from grass-fed cows (consuming over 50% of their daily dry matter intake as grass during the grazing season) compared to cows with no access to pasture. Increases in CLA (25-30%) and omega-3 FAs (36%), and the lowering of the ratio of omega-6:omega-3 were found in milk from grass-fed cows during the grazing season with omega-3 being higher throughout the year when compared to milk from the conventional herd. The impact of processing protocol (homogenization, pasteurization, and sterilization) on the lipid profile of whole milk (standardized to 3.25% fat) was also conducted on milk collected from the two farms during the 3rd grazing season. The long-chained FAs, both unsaturated (CLA and omega-3 FAs) and saturated, were stable through the heat treatments, while homogenization tended to degrade the long-chained saturated FAs to shorter lengths. Therefore, the processed milk from the organic herd continued to have the higher levels CLA and omega-3s. Our studies have shown that the most significant difference between our two herds is the higher levels of healthy lipids in milk from grass-fed organic herds. Therefore, milk from grass-fed herds should be incorporated into dairy products, such as specialty milk products and cheese, where the elevated levels of healthy lipids can aid in benefitting human health.