Rapid gas chromatography identification technique determines treatment of muscle foods.

The application of natural wood smoke, filtered wood smoke and carbon monoxide has become a very effective way to maintain or enhance the color properties of red muscle foods when they are stored under refrigerated and frozen conditions. Because some of these applications are faced with regulatory restrictions in certain countries, techniques must be developed that can identify and verify how a muscle food product with enhanced color is treated.

The objective of University of Florida scientists was to develop a rapid identification method based on gas chromatography (GC) that would identify and verify which gas or smoke treatment was applied to the muscle food. The researchers wanted to generate a fingerprint for the specific type of gas or smoke with which a muscle is treated. The technique they came up with will make it possible to identify and verify the type of gas or smoke treatment applied to muscle foods to maintain or enhance the product's color stability. This will have important implications for quality control as well as regulatory enforcement.

Fresh tuna steaks were treated with carbon monoxide, natural wood smoke and filtered wood smoke. The investigators placed the treated samples into gas tight vials, which were heated to force the adsorbed gas components into the headspace of the vial. Gas standards were used to obtain retention indices with the GC. A headspace sample from each vial was then injected into the GC, and the chromatogram was then evaluated and compared to the standard chromatograms.

Tuna steaks treated with different batches of the same smoke and gas process produced the same gas chromatogram. The gas chromatogram differed between the different treatments. Unique peaks were identified for each treatment, which made it possible to identify which treatment had been used on the tuna. The scientists also analyzed the gases used for treatment. The analysis indicated the expected fingerprint chromatogram.

Further information. Hordur G. Kristinsson, Department of Food Science and Human Nutrition, University Of Florida, 130 AFPP, Newell Drive, P.O. Box 110370, Gainesville, FL 32611, phone: 352-392-1991; fax: 352-392-9467; email: hgkristinsson@mail.ifas.ufl.edu.