The word halal, which means "allowed" in Arabic, refers to that which is permissible under Islamic law. Like the word kosher in Judaism, it is most commonly associated with food products sanctioned by the religious leadership.
Within the U.S. Muslim community, suspicion has grown in recent years about meat sold under the halal label as the number of suppliers expands and standards of animal slaughter get new, modern interpretation by a growing network of certifying agencies.
Generally speaking, after a short prayer, animals are to be killed with a sharp blade drawn across the throat. That allows the blood considered unhealthy to the Muslim diet to drain. In a standard slaughterhouse, a cow, for example, would be killed with a bolt gun and then bled.
But with the growth in the U.S. Muslim population in recent decades, halal foods have become a $20 billion-a-year industry, according to an estimate from the Islamic Food and Nutrition Council of America in Chicago. As more meat is turned out by larger, more efficient operations, the traditional method of a man and a knife is no longer considered an absolute necessity by many Muslims.
"The slaughtering of the animal is a pretty simple practice," said Zain Abdullah, an associate professor of religion at Temple University. "But there is a cadre of scholars that Muslims will follow. They interpret the religion for the community, but there are usually multiple interpretations."
In some large-scale slaughterhouses, recordings of prayers are played over loudspeakers. In others, the only rule is to have a Muslim in the room when the animal is killed, said Maria Omar, spokeswoman for the Chicago council, which acts as a certifying agency for suppliers and as a consumer-education group.
"It's no different from the organic market or gluten-free market," she said. "When there's no fixed standards, a lot of people are taken for a ride. A lot of people don't even think to ask, what do you mean by halal?"
A range of Muslim certification agencies has sprung up to sign off on modern assembly lines where Muslim workers pray as animals are killed at a quick pace by mechanical blades.
Their argument is primarily economic. As they see it, if every animal were hand-slaughtered, many Muslims would not be able to afford to eat halal at all.
"Our community is trying to figure out not only what the standard should be, but what is practical," Omar said.
As the debate rages on, consumer-protection laws have passed in at least seven states, including New Jersey. There, halal retailers and slaughterhouses are required to fill out a detailed questionnaire regarding everything from the food's alcohol content to whether the animal was stunned before slaughter. The survey results must be posted for public view.
But there is virtually no enforcement for those who run afoul of the laws, Omar said.
The question of what is and isn't halal extends to many aspects of Muslim life - from whether women should keep their faces covered to whether Muslims in Dubai can sell liquor to expatriates.
And for many, machine-slaughtered meat is simply part of living in the modern world.
Ahmad Shadid, a Muslim travel agent in Jersey City, N.J., who books pilgrimages to Mecca, said he found the idea of questioning the halal label unsavory.
"Everybody has their own understanding of the religion. This is not going to change. It's like, when is the beginning of Ramadan and the end of Ramadan?" he said. "I have a busy job. I don't have time to slaughter my own meat. If the guy says it's halal, I accept that."
But some Muslims have rejected eating meat slaughtered by machine. That is especially true for new immigrants from North Africa and South Asia, where households commonly slaughter their own animals, Abdullah said.
"African Muslims in Harlem, they felt compelled to set up their own African butcher shops," he said. "For immigrant communities, it's religious, but much more it's a matter of tradition."
Oftentimes, consumers are left in the dark as to how exactly the animal they're eating was killed.
The Brown chain of ShopRites, which has 10 stores in Pennsylvania and New Jersey, began expanding their halal offerings in 2005 and are installing isolated halal butchering rooms and meat cases in their new stores.
Asked how their meat was slaughtered, co-owner Sandy Brown said she was not sure because ShopRite buys from a wholesaler and not directly from a slaughterhouse.
"I'm 99 percent sure it's hand-slaughtered," she said. "There's a couple of mosques we work with, and whenever we do something new, we check with them."
The lack of a unified industry standard is driving suspicion, said Amr Scott, owner of Quetta Halal Meat Market near Rittenhouse Square and a strict proponent of hand-slaughtered meat.
"People see a halal label, and they think a Muslim signed off on it, so it's OK," he said. "But everyone has a different standard. It's utterly ridiculous."
For the generations of Muslims who came to the United States in the 1950s and '60s, detailed questions about what food was halal were not an issue, because there were almost no halal shops. They traveled hours to trusted vendors or killed their own.
"I remember my dad would drive to a farm down in Virginia to slaughter his own chickens," Scott said.
But now, with so many halal suppliers to choose from, those tasked with determining the rules by which Muslims eat find themselves answering questions that never would have arisen centuries ago.
At a conference in India earlier this year, Islamic scholars argued over the validity of chicken plants installing buttons on their assembly lines so each chicken could be killed by an act of man and not automation.
Ra'id Abdul-Malik, a teacher at the Association of Islamic Charitable Projects mosque in West Philadelphia, consults centuries-old writings to answer questions such as, "Could a Muslim eat an animal hit by a car?" The answer is yes, as long as the animal is not killed in the accident but by a knife across the throat after the fact.
"It doesn't have to be something based on logic," Abdul-Malik said. "Humans do not always know what is acceptable."
Contact staff writer James Osborne at 856-779-3876 or firstname.lastname@example.org.