SDSU research: DDG increases healthful fatty acids in milk
A program to groom leaders for southern African nations is also producing South Dakota State University research that could add value to dairy products.
Researcher Rosemary Nyoka of Zimbabwe is finding that supplementing the diets of grazing dairy cows with dried distillers grains or fishmeal could increase the level of healthful fatty acids in milk and milk products such as cheese.
“With this potential to improve the healthful fatty acids, we are finding additional uses for distillers grains,” Nyoka said. “We are also trying to improve profitability for dairy farmers. We are hoping they will be able to sell these products at a premium.”
Nyoka, is working towards a Ph.D. in dairy science at SDSU and is also a Fellow of the Kellogg Southern Africa Leadership, or KSAL, Program.
Viwe Mtshontshi, senior program officer from AED, a Washington, D.C.-based organization that administers the KSAL program, said the organization is very pleased with level of support given by the faculty in the SDSU Dairy Science Department.
“Nyoka’s chosen area of research meets one of the Kellogg Foundation, Africa Program goals — addressing the challenge of food security in southern Africa,” Mtshontshi said.
Nyoka’s research is evaluating the extent to which dietary manipulations can improve the levels of healthful fatty acids in milk.
“I’m supplementing cows on pasture with fishmeal and distillers grains to see how much these high-fat diets will improve the concentrations of the healthful fatty acids in the milk and dairy products,” Nyoka said. “I will analyze to see how much fatty acid has been added to the milk through the diet, and then I’ll process the milk and analyze to see how much fatty acid has been added and retained in the cheese.”
Nyoka is monitoring healthful fatty acids called conjugated linoleic acids, or CLAs.
“These CLAs are known now to have anti-carcinogenic properties, as well as anti-arthritis and anti-obesity properties. They’ve also been known to improve bone formation,” Nyoka said. “In general, in an average American diet we are eating maybe 1 gram per day of these fatty acids, while the effective levels known so far are like 3.5 grams of the fatty acids. So we see that in general, people are not getting enough.”
CLAs are found mainly in products from ruminant animals such as milk and meat. Milk typically contains between 0.3 grams and 0.6 grams of CLAs per 100 grams of fat, Nyoka said. But on her trial diets, Nyoka’s SDSU cows produced milk with total CLAs ranging from 2.5 to 5 grams.
“I’m grazing the cows on an alfalfa pasture, and then they get half their daily requirements from a supplement which is either soybean-based, distillers grains-based or fishmeal-based,” Nyoka said.
The soybean-based supplement is the control, since dairy producers commonly use it. The fishmeal- and distillers grains-based diets are Nyoka’s areas of interest.
“Now with the ethanol plants we have a lot of distillers grains, and it has high fat content. Most of the fat in the distillers grains are the unsaturated fatty acids, which are the major precursors for the CLAs,” Nyoka said. “So we want to see how the distillers grains will compare to the fishmeal, as well as to the control diet.”
Nyoka is including cheese in her research because one of her interests is in finding alternative, high-value products that farmers in Zimbabwe can more easily transport to market from remote locations.
As a government dairy officer in Zimbabwe, Nyoka not only helps dairy farmers troubleshoot production issues, she also works with dairy manufacturers. That’s one reason she is studying at SDSU, one of the few dairy science departments in the United States that includes both dairy production and dairy manufacturing under one roof.
Professor Arnold Hippen, Nyoka’s adviser, said one advantage of the SDSU program is that it gives international students a more holistic view of the dairy industry — from the care of the animal to the finished dairy product — while emphasizing animal nutrition.
Vikram Mistry, head of the SDSU Dairy Science Department, said Nyoka is the second Ph.D. student to come through SDSU as a Kellogg Foundation scholar from Africa. SDSU graduate Gaolebale Mpapho has already returned to Botswana after earning her Ph.D.
“We have always talked about how important we are in the dairy education world in the United States,” Mistry said. “This program gives us the opportunity to have an impact beyond our borders.”
Source: South Dakota State University (”http://www3.sdstate.edu/SDSU/NewsDetail45702.cfm?ID=46,6612“)
August 27 2008 09:50 pm | Uncategorized