Al Booren, a professor of food science at Michigan State University in Lansing, Mich., says that this type of analysis measures the total crude fats in a sample. Crude fats cover the whole range of animal fats.
The kind of analysis a processor would do is different from that done in an academic setting. “They work to get it as close to instantaneous as possible and nondestructive,” Booren says. In academic testing, the sample being analyzed is usually destroyed in the process.
No matter what the process, however, a protocol needs to be established for how the testing will be done: how the sample is taken and analyzed, and other issues. Whatever the protocol, says Booren, they must stay consistent to ensure the most accurate assessment possible.
Careful stepsProcessors have an extra concern. The sample must be as uniform as possible, whether it be blended or from a point in the process where the sampling can get the most homogenous results possible.
“What that may involve is using a blender, or using a number of core samples,” Booren explains. “There are many, many techniques and protocols based on the meat and what you’re doing in your facility.”
The fact that meat can be so heterogeneous will affect the accuracy of any testing. For a processor, an accuracy of plus or minus one percent in fat percentage is what would be expected.
“If a processor comes saying his analysis is accurate to a hundredth of a percent, I’m going to think they don’t understand the nature of whole muscle,” Booren says, adding that it would be easy to see variation in a sample because it wasn’t perfectly blended or a situation where a particular group of muscles has been used, such as ground round, and that will change variability as well.
Getting a readThere are two choices in methods for fat analysis at the processing level. One of the more common is the use of X-ray machines.
Booren says that commercially available X-ray machines are set at laboratory standards and known quantities. The machines are quite reliable once they are standardized for the products being tested.
The advantage of an X-ray is immediate results with no destruction of the sample being used. The drawback is that it requires a large sample, anywhere from two to 10 pounds.
Another method is the use of microwaves. In this case, according to Booren, the machine essentially melts the fat away for measurement analysis. The sample itself is destroyed in the process, but is also very small.
Modern fat analysis equipment has improved from what was previously available. “Many of the rapid methods have become nearly as accurate as the generally accepted lab methods, if the protocol is set up right,” says Booren. “They’re much better than 15 or 20 years ago. [The equipment wasn’t] nearly as sophisticated as they are now. I have a lot of confidence in them, whether you’re working for McDonald’s or a smaller group. You can typically find methodologies for crude fat that are just as reliable.”