Getting the Most of Your Beef
Story and Photo by Kelli Chapman
When buying beef, consumers look for a bright red color and mild odor to indicate freshness. If packers and retailers can prolong this vibrant color, much less beef will be wasted, and the beef industry can be more profitable. The growth of bacteria in ground beef directly affects these quality indicators that consumers use on a daily basis.
Texas Tech University prides itself on innovative research. Texas Tech’s International Center for Food Industry Excellence (ICFIE) and Department of Animal and Food Sciences have been working together to address this challenge.
The pathogen processing lab in the food technology building has been a key factor in achieving numerous research projects. To maximize research success, as well as product quality and safety, this processing lab has been duplicated as closely as possible to the meat lab. One major project that is currently on the edge of success is increasing shelf life of perishable foods – particularly, ground beef.
Alejandro Echeverry, post doctoral research associate and Tech alumnus, works closely with food science professor Mindy Brashears, Ph.D., and 15 animal and food science graduate students in researching ways to increase the shelf life of ground beef. This research began in 2002 and focused on controlling pathogensrelated to various foodborne illnesses.
Echeverry’s goal is to reduce the levels of harmful bacteria that spoil beef to increase the safety of the beef for consumption, and allow grocery stores and supermarkets to carry the products longer. Echeverry said he thinks he and his team have found a way to increase the shelf-life of ground beef by three to four days, and those extra days can greatly benefit the beef industry. He said two main factors help accomplish this shelf-life extension: lactic acid bacteria and modified atmospheric packaging.
Lactic acid bacteria, or LAB, is a bacteria compound naturally found in many living organisms including yogurt, cheese and other probiotics. Echeverry’s study found that when certain useful strands found in LAB are applied to ground beef, the growth of harmful pathogens that cause food to spoil slows. As LAB controls pathogen growth in ground beef, shelf-life is increased. This same concept can be applied in prolonging the shelf life of various vegetables as well.
When injecting the LAB, the Tech researchers have discovered the precise amount of LAB needed to control pathogen growth; however, the researchers have also discovered that it is not necessarily harmful if too much LAB is added. Because LAB cannot be over-administered in ground beef, virtually any amount of LAB added to ground beef is safe to consume.
Still, as effective as it is in maintaining a desired color and flavor for an extended period of time, LAB doesn’t make ground beef completely non-perishable. If ground beef containing LAB is not refrigerated at less than 40 degrees Fahrenheit, LAB can have the opposite effect on meat and cause the ground beef to spoil faster.
Studies involving LAB have been previously used in other Tech research projects, particularly related to fighting the growth of salmonella and E. coli. Only later did this Tech research team discover that controlling pathogen growth was directly related to preventing this harmful bacteria growth, as well as increasing the shelf life of ground beef.
Another major factor in the study relates to the packaging of the ground beef. Since most of the ground beef consumers see is sealed using modified atmospheric packaging, or MAP, Tech researchers have based their research on the use of this packaging to mimic the industry’s conditions as close as possible. The type of packages holds the ground beef in a rigid plastic tray with an absorbant pad under the beef. Any residual air is vacuumed out of the package and is replaced with an alternative gas combination. This gas combination is usually comprised of oxygen, carbon dioxide and nitrogen.
“It’s all about how you package it,” Echeverry conveyed as he explained the variations of shelf life strictly due to packaging methods. Vacuum packaged beef that is boxed and ground in the grocery store will last an average of 35 days while other case ready ground beef has an average shelf life of 10 days.
The project’s results have shown that when air is extracted, and a modified atmosphere of gases is added, this also will increase the shelf life of ground beef. Carbon dioxide is added to this innovative packaging procedure and the desired cherry-red color is prolonged; Tech researchers are working to find the level where maximum freshness can be achieved, but spoiled beef can still be recognizable by the consumer once expiration of the meat has surpassed.
In addition to finding solutions in increasing shelf life of ground beef, The Department of Animal and Food Sciences is continually working to better the food industry and make our goods as efficient as possible.