I recently switched from grain-finished beef to grass-finished beef from a local rancher, and while there's a definite difference in taste and texture, I was expecting to the fat to be a different color, like the yellow/gold fat I lusted over in Tribe of Five and Kurt Harris' blog posts.
Should grass-fed, grass-finished beef have yellow fat or does it depend more on the type of grass they foraged on before slaughter? I live out west and we don't have the lush, verdant pastures of the east so I could see that being a factor, but one of the pulls of grass-finished meat is the caretenoids & O-3, and yellow fat is apparently an indicator of that.
Does the grass-finished meat you've bought tend to have yellow fat, or is it susceptible to regional variation?
Dredging up my memories from working at the Meat Industry Research Institute of New Zealand many years ago: it's dependent on plant species and season. Butter for example is more yellow orange in spring than in winter. Almost all beef here is grass-fed and I see wide variation in fat colour. I wouldn't worry about it.
My understanding is that yes, it will depend on region, but also season. Especially this time of year, most ranchers have to supplement with hay and such.
I say chalk it up to seasonal variation and that as seasonal creatures, our bodies can account for some of that, just as with vit D.
I had to ask this same question when I was able to purchase a pastured steer from a local farmer here in west Michigan. I had no doubt it was pastured raised--very little intramuscular fat and he was nearly 3 years old. And the butcher struggled to obtain enough visceral fat to fatten up my ground beef. What fat there was around the perimeter of the steaks and roasts was white. Some sections had a slightly yellowish hue, but mostly white. So, I looked into it and came to the conclusion, as you state, that it's the level of caretenoids in the forage. I understand a pasture overrun with dandelions will produce yellow fat if the animal is processes shortly after clearing it. I've bought my beef steer from this guy for the last three years and have wondered if it's feasible to have a sample of the fat analyzed at a lab.
As has been mentioned before, diet, season, and location of the fat all play a part.
In the beef I get, fat around organs and "internal" cuts (strip steaks, etc.) are white. External cuts like brisket, oxtail, shank, etc, all seem to have yellow to yellow-grey fat. Subcutaneous fat will sometimes end up on the yellow side of things whereas the intramuscular and abdominal cavity fat will be milky white.
The texture will be different too. Yellow fat = stringy, loose, gristly. White fat = soft, dense, and NOM.
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