dwacon wrote:

> I was watching that documentary on hamburgers that was
> on cable last night. This guy from Texas was saying that
> if cows eat only grass, their fat is yellow and yellow fat
> won't stick to your arteries.
> It is corn fed cows that produce white fat which will kill you.
>
> Is this guy full of it or is he onto something?

First, who was this guy? A cardiologist?
A guy who raises grass-fed beef?

If the latter, do you expect him to give you
a fair and balanced evaluation of the difference
between grass-fed and grain-fed beef?

The difference in color (if any) will be caused
by carotenoids and xanthophylls (oxidized
carotenoids) in the feed. Both grass and grain
have food value (calories), but not a lot of fat.
The fat is formed in the cow, mostly from the
carbohydrates in the feed.

Feed rich in fat can affect the ratio of saturated
fat (bad fat) to unsaturated fat (good fat) in
some animals. If anything, I would expect
the polyunsaturated corn oil from a corn-based
diet to result in more healthful ratio of saturated
to unsaturated fat.