Brigitte Schwendel

Citation

Thesis Title
Differentiation between organic and conventionally produced milk in pasture based farming systems

Read article at Massey Research Online:

Consumer perception of organic cows' milk is associated with the assumption that organic milk differs from conventionally produced milk, justifying premium prices. Ms Schwendel investigated whether chemical composition differed between milk produced by these two farming systems. Sampling was conducted on two farms sets, each comprising one organic and one conventional farm. All farms applied year-round pasture grazing. Milk samples were collected throughout the milking season and analysed for free oligosaccharides, fatty acids, major casein and whey proteins, milk fat volatiles, and a limited set of milk metabolites using nuclear magnetic resonance. Fatty acids were influenced by breed and fertiliser application. Oligosaccharides differed between farming systems, with causes currently unknown, while farm set was the dominant influence factor on protein composition. Those factors influencing milk chemical composition are not exclusive to either farming system, and pasture feeding conventional cows will remove differences previously reported for organic and conventionally produced milk.

Supervisors
Professor Patrick Morel
Dr Don Otter
Mr Craig Deadman
Professor Nicola Shadbolt
Associate Professor Tim Wester
Dr Mike Tavendale