Two news items yesterday got me thinking that I should seriously consider eating less meat to help slow climate change.
The first is about research in New Zealand to get sheep to burp less, according to the Wall Street Journal (Feb 26, 2009, page A1). That’s because when sheep—as well as cows, deer, and goats—burp, they emit methane, which is a more potent greenhouse gas than the carbon dioxide emitted by nonruminants such as pigs, chicken, and humans. Ruminants have complex stomachs that enable them to digest leaves, grass, hay, and other cellulose-rich food; a digestion by-product is methane, produced by methanogenic bacteria in the ruminants’ gut. The researchers are trying various ways to reduce methane in the burp, from modifying the diet to breeding animals that would eat less grass.
These efforts apparently are necessary because New Zealand “is home to about 35 million sheep—nearly 10 times the human population—and millions of cows, deer and goats.” Perhaps if people reduced their appetite for ruminant meat, the methane-rich burps of these animals would not be so problematic. We would still have swine and chicken, wouldn’t we?
Well, maybe scratch pork too, on the basis of the second news item, from Purdue University, about using soybean oil to reduce greenhouse gas emissions in swine barns. The researchers sprayed the barns with soybean oil at a rate of 5 mL per square meter for one minute per day. Aren’t there more valuable uses of soybean oil? Anyway, the treatment reduced methane and carbon dioxide emissions by up to 20%. Okay, except that soybean oil is now more expensive than it was when the study was conducted. “In addition, some of the oil ended up on the floor, the pigs, the feeders and fans,” one researcher says in the press release, raising the amount of energy needed to clean the barn.
I’ll just eat less pork, too. Chicken with broccoli, anyone?