We ask the experts to settle common questions we've all wondered about.
Is organic milk a healthier option than regular milk? What's the difference between the two - and is that difference important in terms of human health or the cow's wellbeing?
Nutrient-wise, organic and regular cow's milk are the same. Both are great sources of protein; equally provide significant amounts of calcium, magnesium, riboflavin, vitamin A, vitamin B12, vitamin D and zinc; both are available in reduced-fat varieties and neither contain preservatives.
Milk, whether from an organic or conventional farm, undergoes similar processes before reaching the consumer, such as pasteurization, homogenization and fortification.
Pasteurization involves heating milk to 72 C for 16 seconds, then cooling it rapidly. The high temperature destroys disease-causing microorganisms, the most notable being Listeria monocytogenes, E. coli and salmonella. This is a crucial step in the prevention of food-borne illness and the preservation of human health.
Milk is homogenized to create a smoother texture. Without homogenization, the cream or butterfat separates and forms a thick layer that floats on top of the milk. A homogenizer breaks up the fat into smaller particles that are evenly dispersed throughout the milk. In Canada, we commonly refer to milk that is not reduced in fat as "homogenized" when in fact almost all milk, including fat-reduced varieties, is homogenized.
Milk in Canada is fortified with vitamin D. Skimmed and partly skimmed varieties are also fortified with vitamin A. Milk that contains a higher level of fat doesn't need to be fortified with vitamin A because it already has a sufficient amount of the vitamin, which binds naturally to fat.
The differences that exist between organic and conventional milk production involve farming practices.
Organic dairy farmers feed their cows with crops grown without pesticides. This, however, does not mean that conventional dairy farmers don't provide their cows with good-quality feed or follow environmentally friendly practices. Field crops generally contain minimal pesticide residues.
On either farm, cows that develop an infection are given antibiotics. The difference lies in whether the treated cow's milk is ever returned to the milk supply.
On a conventional farm, the milk from the treated cow is discarded for a period of time referred to as the withdrawal period. This includes the time the cow has been on the antibiotics plus the time it would take the drug to be excreted from the system.
On an organic farm, once a cow requires antibiotics, its milk is never again used for human consumption.
In either case, strict guidelines and testing are in place to ensure that the milk that reaches the consumer is free of antibiotic residue.
Neither type of farming has a large impact on human health or the cow's wellbeing. The choice to purchase organic foods is a personal one. If you choose the organic route, purchase products that are federally certified as organic and carry the certification logo. This ensures that strict criteria are followed during production. As of June 30, 2009, mandatory certification of organic products in Canada will be required.
Daniela Fierini is a registered dietitian with the hematology-oncology program at Princess Margaret Hospital at University Health Network in Toronto.
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