Grass-fed beef is beef which has been raised on a diet of grasses, rather than grains and a variety of food industry byproducts. At one point in American history, all beef was grass-fed, because farmers simply turned their cattle loose onto the grasslands, periodically collecting them for slaughter and processing. However, cattle farmers learned that by keeping cows in Concentrated Animal Feeding Operations (CAFOs), they could quickly raise cattle to maturity on a feedlot. Because of the higher expense to raise, grass-fed beef occupies a niche market in most of the United States, although a growing number of consumers are turning to grass-fed beef because they believe it has advantages over conventionally farmed beef.
The normal diet of a cow is grass. Cows and other ruminants have evolved complex digestive systems to turn grasses and roughage into food, and when materials like corn are introduced into their diet, the cows often suffer intestinal upset and an acid imbalance which can be a breeding ground for bacteria which are potentially dangerous to humans. However, corn fattens a cow up quickly, so the cost of treating the intestinal problems is balanced out by the fact that the cow is ready to slaughter in as little as 18 months. Because of the unusual diet of feedlot cattle, the cows are given antibiotics to fight off infection, a practice which public health officials are worried about. However, the relatively low cost of raising feedlot cattle makes it highly appealing to most ranchers.
Grass-fed beef is raised in a free range fashion, and rotated periodically from pasture to pasture to allow the grass to recover. Farmers who raise grass-fed beef must actually invest more time in the quality of the pasture than the cattle, to ensure that the grass is providing the best nutrition possible. The ability to roam freely, which is natural, is less stressful for the cattle than a CAFO environment, and also better for the environment in general, as the manure is spread out across a large swath of land, rather than being concentrated in a sewage lagoon. Responsible farmers are also careful about where their cows roam, to ensure that they do not disturb delicate ecosystems by stirring up the mud in rivers and streams and breaking down their banks, threatening aquatic life.
Because grass-fed beef is older at the time of slaughter, the meat has a different texture than feedlot beef. It tends to be leaner, and also somewhat more muscular; it takes work to learn how to cook grass-fed beef well, but some consumers think it is worth the effort. Nutritional analysis of the meat has shown that it is higher in omega 3 fatty acids, as well as vitamins A and E. In addition, because grass-fed beef is never fed animal byproducts, the risk of mad cow disease is very low, unless a cow was infected before it joined the herd. Grass-fed beef is often available directly from the farmer, allowing consumers to see where their meat is raised, and specialty grocery stores carry it as well. When seeking out grass fed beef, be careful about deceptive labeling such as “grass finished beef,” which has not been grass-fed in entirety.