August 28, 2013

Brown ground beef?

By Dr. Robert Campbell

I have had people ask me in the past why supermarket ground beef is red on the outside and brown in the middle. Surprisingly, due to the nature of the pigment in ground beef, that is actually an indication of fresh ground beef – as long as it is bright pink on the outside and about half an inch into the package you see brown spots or brown through the center but pink on the outside. You only need to worry about ground beef if it is brown on the outside. That is an indication that it has been out too long. Ground beef has 3 normal color states – bright red (oxymyoglobin state), dark red-purple – deoxymyoglobin (no oxygen) and a state called met-myoglobin that is brown.

The meat starts out in a state oxymyoglobin (bright red) just after it is ground. When it goes into a package the inside portion isn’t getting oxygen any more, so it turns brown (met-myoglobin) before turning purple red (deoxymyoglobin). It takes about 2-4 hours for the ground beef to turn dark red after it is in the package. It has to go through the brown color before turning to the purple color – if you spread the package out and leave it in air it will re-bloom to bright red in 15 to 20 minutes. If you look carefully the first 1/4 to 1/2 inch; the meat will still be red. Sometimes it is splotchy brown because oxygen is getting to parts of the package but not all the way through. If the meat is old it gets brown on the surface first when it runs out of met-myoglobin reducing capacity. The meat at the surface runs out first and gets stuck in the brown state once the enzyme system runs out of energy.

Basically if the meat is brown on the inside when you open it up, and pink on the outside, the brown meat will turn pink in a short period of time showing that the meat is fresh.


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Dr. Robert Campbell

About Dr. Robert Campbell

Bob Campbell has been the meat business for a long time (even before he became a Ph.D.) He has worked for every sized meat plant from the local butcher shop and slaughterhouse in Willington, Connecticut to the largest international meat processors. Along the way from small town Connecticut to international meat processing he has found that people are always interested in how meat is processed, how it fits into healthy and enjoyable eating and how to prepare it safely. Meat can be an important part of the diet for those of us at 6’s and 7’s and showing less experienced folks (like our kids) how to cook and prepare meat so it is safe and tasty is one of the things I’ll talk about here. I started out in this business in the late 60’s as a traditional butcher’s apprentice (mom said I needed a job) and it has turned out to be my profession. When I got to college I discovered that there was something called meat science and that the meat lab need experienced help to help it do research and provide practical experience to the students so I ended up with a degree in agriculture just as the economy hit the skids in the 70’s. So I went off to grad school and got an MS in food science. After that I came back to the east coast and started working for the Howard Johnson restaurant chain – the French chefs would dream up something and give me a recipe for 5 pounds and I had to scale it up to 500 lb at a time which got me deeply involved in the process of making foods and scaling them up to industrial processes. When HJ shut down their commissary department, I got a job with IBP – at the time the largest processor of cattle and pork in the world (IBP was later bought by Tyson and the largest meat company now (2013) is called JBS). After IBP I went back to school and worked for Kansas State for 10 years doing meat research and international outreach so I have processed and tasted meat on or from every continent except Antarctica. I also managed to get a Ph.D. in Food Science. Since receiving my Ph.D. I have worked for companies that canned meat, made pork rind snacks, spent some time consulting in food safety and R and D and currently am Food safety director for Kayem Foods Inc. My fortunate meeting with Dr. Rappaport at a friends’ wedding has led to a long friendship and enduring interest in her projects. Because of the questions I have gotten from people all over the world on how to prepare food that is safe delicious and nutritious, I agreed to be part of 6’s and 7’s. People need a place to go that provides current, clear and correct ideas on how to live healthy and happy. Eating is a major part of that and I trust you will find the information we provide will be useful, understandable and will help you as part of the first generation that makes the active 6’s and 7’s the most interesting and fulfilling part of your lives so far.