The chicken you're cooking for tonight's dinner may be free-range and organic. But can you taste whether the bird is male or female?
These days, consumers aren't just demanding that the animals they eat be raised humanely. Increasingly, they're also wanting to know the gender of the beasts, says Sam Gundy, co-owner of the Toronto high-end butchery Olliffe, Purveyors of the Finest Meats.
For certain animals, particularly chickens, males and females yield somewhat different meat, Mr. Gundy says. (He notes they're generally referred to as males and females, rather than roosters and hens. )
Many customers are starting to ask for male chickens, he says, because female birds are believed to have higher levels of naturally-occurring hormones, which some people want to avoid. But, according to associate professor Gregoy Bedecarrats of the University of Guelph's Department of Animal and Poultry Science, the biological half-life of naturally-occurring hormones, such as estrogen, is fairly short. The likelihood of these hormones accumulating in the tissue or fat of the birds, then surviving the processing and cooking, is low and wouldn't affect consumers' health. While male birds may have slightly higher levels of testosterone and females could have minimally higher estrogen levels, broiler chickens, those typically found in grocery stores, reach only about seven weeks of age, so their hormone levels are low, Dr. Bedecarrats says.
Hormones aside, however, there's also a difference in the physical composition of male and female chickens, Mr. Gundy says.
"Female chickens have more fat. Male chickens yield more protein, which means there's actually more of the meat," he says, noting that while he can't distinguish any difference in taste, there is a difference in the way it feels in the mouth. "You know you have a big fatty steak, you can tell there's that satiating fat going on? With a female chicken, you get more of that fatty flavour – not greasy, but you can just tell there's more fat."
Depending on the species and the ages of the animals, however, these kinds of sex differences can be subtle – perhaps too subtle to require any differentiation in how they ought to be cooked. And to some palates, they may not be discernible at all.
At Rockweld Farm Ltd. in Abbotsford, B.C., co-owner Flo Rempel says some customers ask specifically for roosters. But while roosters are typically larger, she says, it's hard to spot the difference between processed male and female birds.
"Even if you come to our store, I could guess that maybe our bigger ones are roosters," she says, but "I don't think, once they're processed, there is any sure way to tell."
Besides chickens, Mr. Gundy says gender differences are likely most apparent in wild boar meat. The males tend to be leaner and gamier in flavour, while the females tend to be more tender and taste milder. But in regular pork, for instance, pigs are generally slaughtered when they're around a year old – too young for any noticeable differences to develop, he says.
Such differences don't typically emerge until pigs are around four to five years old, says Fred de Martines, co-owner of Perth Pork Products Ltd. in Sebringville, Ont., which sells rare and heritage breeds. But male pigs that reach maturity tend to be used for breeding, not eating. And younger males sold for meat are usually castrated to prevent "boar taint," a distinct and unpleasant odour specific to males that can render the meat inedible.
While some people ask for female pigs because they perceive them to be milder in flavour, Mr. de Martines says he doesn't believe their meat is markedly different from males that lack boar taint.
"Personally, I cannot taste the difference," he says, "but everybody's taste buds are different."