“Slime” has negative connotations. We don’t like to eat slimy food or touch slimy things. Now another type of slime has made its way into our consciousness – “pink slime.” Pink slime has caused concern among consumers. It has stirred up our “food fears.”
Pink slime is a misnomer for “lean finely textured beef.” USDA recognizes LFTB as a safe and wholesome beef product and many meat processors use it. According to one estimate, 70 percent of the ground beef in the U.S. contains LFTB.
“Paste” more accurately describes LFTB than does “slime.” Slime tends to contain more liquid than does paste. Slime contains 96-98 percent moisture, while the moisture content of LFTB is 55-65 percent. Processors use tomato paste, fruit paste, and fish paste in many food products. A paste is a semi-solid mixture of liquids and solids.
LFTB is a product of normal beef processing. After a beef animal has been slaughtered and skinned, processors remove large pieces of fat from the carcass. A typical 700-pound carcass yields approximately 140 pounds of trimmed fat. This amount of fat contains 15-20 pounds of lean beef.
The lean beef in the fat is valuable because the beef contains a large amount of protein. However, processors cannot cost-effectively remove the lean beef from the trimmed fat with a knife, Dr. Edward Mills, a meat scientist at Pennsylvania State University, explains. Instead, to separate the lean beef from the trimmed fat, processors first heat the fat until it melts and then they centrifuge (high-speed spinning) it to recover the lean beef from the fat.
Processors have several options for the lean beef that they extract from the beef carcass fat. They can simply throw it away – an economically unacceptable option. Or they can sell the recovered lean beef to pet food manufacturers. However, the market for this lean beef in the pet food industry is limited. A third option is to texture – finely ground – the lean beef, forming LFTB, and incorporate it into fresh ground beef. Texturing greatly reduces the size of the meat particles, greatly improving its palatability and nutrient digestibility. Mills describes the consistency of LFTB as similar to baby food. USDA puts LFTB in the same category as boneless lean beef.
Beef processors add LFTB to fresh ground beef at an inclusion rate of 10-15 percent, Mills says. If it is added at higher concentrations than this, the final ground beef product will have a “pasty” consistency. Mills adds: “High amounts of LFTB in ground beef will negatively affect the consistency of the final product.”