Sustainable cattle ranchers aim to correct decades of error. The return to grass-fed beef is one of those sustainability rebounds that, prior to the chemical farming era, was just a d'oh. Still, I wondered what makes grass-fed meat so special. So I asked a local rancher.

I almost wish I hadn't, because Mark Pasternak's answer was so graphic, ranging from entrails to excrement. But for the cause of sustainability, I'm compelled to document here why grass-fed beef actually benefits us all, even vegetarians (who are invited to stop here and read their horoscope instead).

Pasternak, who with his veterinarian wife, Myriam Kaplan-Pasternak, owns the 65-acre Devil's Gulch Ranch in Nicasio, explains that not all meat-producing animals are better on a grass diet. Grass-fed chickens make pathetic poultry. Forget about grass-fed pigs. These critters need other foods in their diet. But animals with complex digestion find grass to be just the thing. They love to graze.

"Ruminants, such as cows and goats, or pseudo-ruminants, such as rabbits, are the only animals that thrive on strictly forage," says Pasternak, whose sustainable ranching operation produces slow-food consumables from meats to wines. In fact, Devil's Gulch supplies grass-fed beef to such esteemed Bay Area restaurants as Chez Panisse and the French Laundry.

Why is this meat from grazing cattle so special? When the cows are left to roam and forage, they contain more of the good, cancer-fighting fat and less of the bad, heart-attack sort. The cows are healthier, so it stands to reason that the humans who feed on them might also be healthier.

"These animals were not intended to eat soy or ground-up brains or leather," Pasternak says. "They were intended to eat grass. So when you feed them other stuff, grains in particular, they get big and fat, and the meat has more marbling. Some argue that this is an advantage. But the meat these animals produce is much lower in the good saturated fats, the conjugated linoleic acids that are important." Conjugated linoleic acids are anti-carcinogens.

"It's not only about the health benefits," Pasternak continues, "but the environmental benefits." When you put cows out to roam, they wander around eating grass and distributing their excrement; in contrast, the dung in feedlot operations builds up to a point where the fumes are bad for both animals and workers. The excrement is hauled and dumped where it causes a nitrogen overload that is functionally toxic for the environment.

Free-roaming animals, Pasternak asserts, may be good for the climate as well. "There are some studies that suggest that these animals may even sequester carbon," he says. The animals prefer to wander. "They were meant to be out on the hill, not confined to a feedlot." Pasternak shares my cynical assessment of the chemical-fertilizer industry, which created the corn-fed beef fiasco in the first place. "Cattle fed on grains and corn produce less healthful meats which require a lot of medicine and doctor visits," Pasternak says. "The chemical and pharmaceutical industries benefit very well from unhealthful meat produced from feedlot animals."

Grass-fed beef, like most other ingredients in a slow-food meal, is not cheap. But anyone who's read Fast Food Nation knows the health risks of eating cheap beef; that book, in fact, practically made me a vegetarian. But local beef, grass-fed beef, is luring me back to full omnivore status.

Locally grown, grass-fed beef will be served when foodies celebrate a 400-page meat bible that hit the market early this month called 'Good Meat: The Complete Guide to Sourcing and Cooking Sustainable Meat,' by Deborah Krasner.

Krasner appears at the Long Meadow Party, benefiting Slow Food Napa Valley, Saturday, Sept. 18. Long Meadow Ranch, 738 Main St., St. Helena. Noon to 5pm. $25–$35. 707.963.4555.

She joins Pasternak for a lunch of rabbit and pork at the Marin-Petaluma Slow Food event on Sunday, Sept. 19, Nicasio Druids Hall, 4499 Nicasio Valley Road, Nicasio. 11:30am–3pm. $25; potluck. For details, 415.640.7596.

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