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New Process For Tenderizing Meat Promises To Benefit Consumers And Meat Packers

A new process that instantly tenderizes boneless meat could help packing houses produce consistently tender, moist cuts of beef, according to a University of Wisconsin-Madison meat scientist.

“We can take cuts such as top rounds, eye of rounds, or rib and loin steaks and improve their tenderness by 25 percent to 30 percent in the blink of an eye,” says James Claus of the Department of Animal Sciences. “This could have an enormous impact on the meat industry”s ability to produce more tender products.

“Cuts that are already tender, such as filet mignon, don”t need to be more tender,” Claus says. “The new process increases the tenderness of cuts from the least tender animals the most. The greatest improvement is in meat cuts that are leaner and less marbled, which are typically from the lower USDA beef quality grades. The result is that meat treated this way will be more consistently tender.”

Tests show that the method also works well on pork and chicken breasts. Claus found a 28 percent improvement in the tenderness of pork loins, for example.

To tenderize beef, the industry currently may age meat for one to two weeks, use blades or needles that slice into or puncture meat cuts, or add plant enzymes to the meat. Claus”s tests at the UW-Madison”s Meat and Muscle Biology Laboratory showed dramatic increases in tenderness of unaged meat. The new method performs as well as or better than blade tenderization, he says, and it doesn”t break the surface of meat. (Processes that break the meat surface increase the risk of bacterial contamination.) Another advantage of the process is that nothing is added, such as plant enzymes, which may give meat an undesirable flavor or texture.

The new process uses electrically generated hydrodynamic shock waves. Like a sonic boom traveling through the atmosphere, the shock wave speeds through the meat breaking apart some of the tiny fibers in the muscle cells. In addition to improving tenderness, this process also improves the ability of meat to absorb and retain moisture, according to Claus. He says the method does not change the meat”s flavor or color.

Hydrodyne Incorporated of San Juan, Puerto Rico holds patents for tenderizing meat with electrically created hydrodynamic shock waves. The company provided the machine Claus evaluated. His experiments at the College of Agricultural and Life Sciences were supported in part by grants from the Wisconsin Beef Council.

The concept of tenderizing with shock waves is not new. An earlier Hydrodyne method attempted to tenderize meat using explosives to generate the shock waves. With that method, meat had to be vacuum-wrapped and submerged in water. In the new process, which Hydrodyne calls the TenderClass Process, the meat never comes in contact with water and does not have to be packaged in a vacuum bag. Also the new electrical-based system produces higher shock wave pressures and allows an operator to treat meat more than once if needed for greater tenderness. The unit Claus used takes as much space as a small pickup truck and does not require any unusual electrical current.

In 1999 the first attempts at using an electrically generated shock wave to tenderize meat were not successful. Using his skills as a meat scientist and familiarity with the meat industry”s needs, Claus conducted studies in collaboration with Hydrodyne and the process”s inventor, John B. Long. Those studies led to significant improvements in the process.

Representatives of several leading companies have visited Madison to see and test the machine. Claus says the meat industry may find the process especially useful in tenderizing what are known as sub-primals and individual muscles used to produce case-ready steaks.

Claus also used the machine to tenderize beef and pork cuts before injecting marinade. The treated cuts retained 5 percent more marinade, which improved their juiciness.

The process also could be used in preparing broilers for market. “It would allow that industry to remove breast meat from bone immediately rather than storing the birds in ice first. We found that breasts removed immediately and subsequently treated post-rigor with this shock-wave method were as tender as breasts harvested using the current method,” Claus says.