Cattle involved in Comerford’s work were born at the University’s Haller Beef and Forage Research Farm near the University Park Airport. Farm manager Pete Le Van explains that researchers are trying to combine the best genetics for carcass quality with a management system that would be profitable.

Le Van and his staff look at carcass data from the offspring of bulls and then use the bulls that pass on the most desirable traits for more breeding. “Selecting genes for marbling is something that has been available only in the last 10 years or so,” he says. “You can’t hurry this kind of research. From the time we breed a cow with a bull that has genes for high marbling until the resulting calf can be harvested at 13 to 14 months of age, it takes two years. It takes about six years to turn over a herd.”

Pete Le Van, manager of the Haller Beef and Research Farm, says the college is developing a beef herd with traits that are high for production and carcass merit—a herd that will be a leader in the industry.

Comerford is now studying how feeding and handling of steers at an early age affects carcass quality at the time of harvest. “We are studying backgrounding time—the time between when a calf is weaned and when it goes into a feedlot,” he explains. “Our preliminary information suggests that this backgrounding phase is extremely important for the expression of high marbling genetics in the carcass.”

Comerford also wants to do further research on how meat tenderness genes could be expressed. “We can check some carcass traits ultrasonically, but there is no way to test taste other than to slaughter, cut a steak off, cook it, and eat it,” he says. “It takes two and a half years, from breeding to slaughter, until we can evaluate the meat.”

Keith Bryan, senior instructor in dairy and animal science, conducts ultrasound examination of a steer, analyzing marbling—fat distributed through the animal's flesh that contributes to juiciness and taste.

Meat evaluation for qualities such as taste and tenderness is done by consumer or trained sensory panelists in Penn State’s Sensory Evaluation Laboratory. “Tenderness can also be predicted by a shear test, which measures how much force it takes to cut meat,” says Comerford.

Responding to consumer demand
Penn State beef cattle research has continued in the face of a decline in the consumption of beef since the 1976 high of 94.4 pounds per capita. Consumers now prefer lower cost, lower-fat meals featuring poultry, which has forced changes in how the meat industry markets products.

Annual per-capita beef consumption has held steady at around 67 pounds for the past decade or so, according to meat scientist Ed Mills. “Consumption of ground meat has increased to the point where about 45 percent of all beef consumed is ground for use in products such as hamburger, pizza toppings, and fillings for burritos, tacos, and other Mexican foods.”

However, Mills notes, even as the demand for ground beef has grown, so has the market for high-quality beef. “While we are consuming less whole muscle meat, there is a stronger demand for very high-quality meat—tender, really great-tasting steaks,” he says. “That demand is driving our beef cattle research. There is a great need, especially in Pennsylvania, for cattle bred for high marbling, and fed and handled to express that trait.”

A highly marbled steak (left) has small amounts of fat dispersed throughout the meat.

Grinding up beef for hamburgers and taco filling can make lower-quality meat seem better. “But if you go into a high-end restaurant and you spend $40 to $50 for a meal, you expect to receive the best cut of beef,” Mills says. “When a steak is put on a plate for a consumer, there is really no way to disguise the quality. So restaurateurs are looking for beef with quality they can rely on.”

Building on success
Few people have an appreciation for how much science is behind beef products and how far producers have come, according to Le Van.

“We have been doing intensive grazing research at the Haller Farm for about 30 years,” he says. “During that time, growth traits have improved dramatically. Now we have what we call ‘five by five cattle.’ They gain 5 pounds a day on 5 pounds of dry matter per pound of gain. Back when I was in 4-H, it was good to have a steer gain 3 pounds a day on 7 pounds of dry matter per pound of gain.”

He sums up current Penn State beef research this way: “We are aiming at developing cattle that are more uniform and yield a higher percentage of meat that is choice and select, with a higher profit margin for producers. High-quality carcass traits result in a more uniform, consistent, and valuable product. We want to see more of the carcass get into the showcase at a supermarket, with less throw-away of fat.

“Ultimately, we are working for a herd with traits that are high for production and carcass merit—a herd that will be a leader in the industry.”

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Faculty and staff referenced in this article are Erskine Cash, professor of animal science; John Comerford, associate professor of dairy and animal science; Pete Le Van, unit manager of the Haller Beef and Forage Research Farm; Ed Mills, associate professor of dairy and animal science; and Donald Nichols, beef unit manager.