GRASS-FED VS. GRAIN-FED
Let’s compare steaks from grass-fed cows—the most similar to those eaten by our ancestors—to steaks from cows raised on increasing levels of corn or other grains. The first thing you will notice in grass-fed beef, besides the higher price tag, is that it is significantly less marbled with fat. Grass-fed beef raised on pasture has a completely different fat profile, and less fat in general. This is due, in part, to several factors: the cows had time to properly ruminate their food, the cows got a lot more exercise, and compared with corn and other grains (or other finishing feeds, which can include beets, molasses, potatoes, crop by-products, soy products, animal rendering and other animal by-products, and even post-retail candy), grass is simply a lower-energy food, less quickly digested.
It’s not like there is no fat in grass-fed beef—cuts near the ribs and loin are still relatively fatty—but the interstitial fat (as opposed to the “visceral” clumps of fat) otherwise known as marbling is dramatically reduced overall. This affects not only the taste of the meat when it’s cooked, but also the rate at which it loses moisture, the cooking time, the overall texture and mouthfeel of the meat, and the extent to which it will brown and form a crust without something to help it along. (See discussion of Maillard reaction here.)
What you might notice next about grass-fed beef is the colour, which tends to be darker and deeper than grain-fed beef when comparing the same cuts. The reason for this is an increased level of myoglobin, the protein present in muscle tissues that perform sustained, hard work. Myoglobin in muscle tissue, like hemoglobin in blood, binds oxygen to iron, making oxygen readily available to cells. It is flavourful on its own, giving meat an unmistakable ferrous taste, and adds more flavour when it is broken down by heating, when it degrades and gives up some of its iron to the interstitial fat in the meat, causing the fat to oxidize somewhat. There are too many flavour-producing reactions going on to explain right here, but we’ll get to this soon.
Finally, you will notice the colour of the visceral fat: the fat caps on the edges of certain cuts like striploin and prime rib, and the clumps of fat in fattier cuts. Cows raised on pasture, or mostly pasture, that eat grass for nearly their whole lives will produce meat with somewhat yellowish fat. This is because of the increased levels of carotenoids—the precursors of vitamin A—they ingest in their diet.
There are good arguments in support of both exclusively grass-fed (pasture-raised) beef and for beef that is lightly finished on natural feed, like whole grains. As for grain-fed beef or beef raised on other concentrated feed products for too long—sometimes for several months, which usually means the cows are raised in abhorrent, crowded conditions and are exposed to pathogens, necessitating regimens of powerful antibiotics and nutritional supplements—I would just avoid it altogether. When raised properly and humanely, cattle have a role in sustainable modern agriculture, especially when the meat they produce is regarded as it should be: a special treat to be lovingly prepared and eaten only as often as our best farming practices can sustain.
The first steak, whether cut from an animal that was hunted or raised, was certainly from a grass-fed animal, but since the advent of agriculture, including grain crops, preceded the widespread domestication of Bos primigenius by roughly 4,000 years in parts of Europe and Asia, I think it is likely that finishing practices were also used even in the earliest instances of beef husbandry. I have found references to grain-finished beef versus exclusively pasture-raised beef dating back to the mid-1700s in Britain, though these comparisons were made, at least initially, only to test the costs of producing meat and milk, and had nothing in particular to do with quality. I would hazard a guess that if we searched for reliable references from much earlier times in the Near East, where both wheat and cows came from, we would find that the earliest cattle herders sometimes finished cows on grain, too.
The meat of the grass-fed steak shown here is darker than that of conventional steak, reflecting a different protein structure and higher iron levels. The fat is yellower, containing more carotenoids.
© 2018 by Rob Firing
By the time steak cuisine had matured to the point where different parts of the cow were being sold for different prices, cuisines from regions around the world, from Europe to Japan, Australia to North and South America, had developed their own names for steaks, their own ways of parsing the animal, their own favourite cooking techniques, their own ways of raising cattle, and their own breeds of Bos taurus (and Bos indicus, the Eastern cousin).
I have come to the conclusion, many, many steaks later, that the particular breed of cow has much less to do with how a steak tastes and performs than one might infer from so much attention paid to heirloom breeds like Black Angus and Wagyu. Determining what makes a good piece of meat has far more to do with how the individual live animal was treated and what it ate. So, for the most part, in this book I steer clear of getting into the merits and history of cattle breeds. Most of the differences among the various breeds have more to do with the shape of the animal, its growth rate, and how the live animal behaves than anything else, and is more relevant to the farmer and the butcher than the steak eater.