All milk is not the same. Research conducted at Iowa State University, in conjunction with Land O'Lakes, shows that the health index of milk varies from cow to cow. Such variability provides an opportunity, because it could open up markets - with premium prices - for those who want to produce dairy products with a high health index.
What is a health index for milk? It is calculated from the concentrations of individual fatty acids (saturated and unsaturated) in milkfat. In general, the greater the proportion of saturated fatty acids in milk - myristic and palmitic acids - the lower the health index. In contrast, the greater the proportion of unsaturated fatty acids in milk - oleic and linoleic acids - the higher the health index. So, from a health standpoint, milk that contains more unsaturated fatty acids is preferred.
If acceptable dairy foods can be manufactured from milk with a high health index, it could become a new market for dairy products.
Earl Hammond, Gene Freeman, Cindie Luhman and I have determined that the health index of milk from individual cows is distributed in a bell-shaped curve. A few cows produce milk with a high index, a few produce milk with a low index, and most produce milk with an average index.
After identifying which cows produced which milk, our research group collected milk from individual cows at the ISU and Land O'Lakes farms that had high, low, and average health indices. Then, we made butter, provolone and cheddar cheeses, yogurt, and ice cream from each category of milk. Here's what we found:
- Milk with a high health index produced butter with enhanced spreadability.
- Cheddar and provolone cheeses made from milk with a high health index was softer, less gummy and less chewy, and it had similar flavor to the same cheeses made from milk with a lesser index.
- Yogurt from milk with the higher health index had a more yogurt-like and vanilla flavor.
- Ice cream made from the higher-index milk was softer and sweeter, but had a more oxidized flavor.
In general, dairy foods made from milks with high health indices have at least equal or usually more desirable eating qualities than do the same dairy foods made from milks with lesser health indices.
This spells opportunity. Milks with a higher health index could be separated and used to produce more acceptable dairy foods.
Involves many factors
Many genetic and environmental factors determine the health index of milk from individual cows. Therefore, breeding, nutritional, and management plans can be adjusted to increase the proportion of cows within a herd that produce milk with a high health index. Some cows have higher health indices because of:
- Younger age.
- Stage of lactation.
- A diet that is conducive to producing milk fat with more unsaturated fatty acids.
With the purchase of a second bulk tank, and the ability to sort milks, a producer could separate a percentage of milk - for example, 10 percent - that has a high health index. This could lead to niche marketing opportunities.
It's definitely something to think about.
Don Beitz is a distinguished professor in the departments of Animal Science and Biochemistry, Biophysics and Molecular Biology at Iowa State University.