LiveScieince.com, NY
08-11-06
Pork Makeover: New Push for Dark Meat
By Sara Goudarzi
LiveScience Staff Writer
Pork is getting a makeover as producers look to make the meat a little darker, an
indicator of higher quality.
In 1987, the pork industry launched a campaign that ingrained the "whiteness" of
pork in the heads of consumers. This push sprang from the perception that
chicken and turkey were leaner choices than beef, lamb and pork. Since then,
researchers worked hard to bring pork up to par and make it the leanest meat it
could be.
Now, Ken Prusa, a professor of food science and human nutrition from
Iowa State University, is convinced that pork is finally lean enough and
consumers need to look at other characteristics when picking the right cut for
dinner.
Pork pH
"I was doing research in a meat-packing plant and noticed that the Japanese
export buyers always chose the darker pork," Prusa said. "I wanted to find out
why, so I evaluated some darker products."
Color, Prusa found through various industry-funded studies, is an indicator of pH
in pork, a measure of acidity or alkalinity. A pH of 1 is considered very acidic and
a pH of 10 is very alkaline.
Dark-colored pork has a higher pH and so is less acidic than lighter-colored cuts.
Acid damages muscle proteins and causes meat to be watery and light in color.
"Through sensory testing, we found pH to be a pretty strong driver of ultimate
pork quality," Prusa said. "Higher pH products are more tender, juicy and
flavorful."
Pork loin, for example, has an average pH of 5.7, whereas the higher quality pork
tenderloin averages around 6.1 to 6.2 in pH, Prusa told LiveScience.
Relax, Porky
Keeping the animals relaxed before slaughter is one way to drive up the pH.
Stress causes elevated adrenaline levels in the body, which then drop the pH
levels in the animal.
Another factor may be temperature.
"Chilling is a big factor in processing," Prusa said. "It's critical to lower the
temperature of the carcass fairly rapidly. Otherwise, the pH may drop too low
before chilling can stabilize it."
With such methods, producers may be able to adjust the pH by a tenth, which
Prusa says is quite significant.
"People can see the difference," he said. "Once they taste it, the better quality is
obvious."
* Better Bacon? Swine + Worms = Healthier Pork
* Food Science: Building Better Steaks, Wings and 'Chops
* Researchers Breed Glowing Pigs
* Cow-free Beef Proposed