Author
Chao, Kuanglin - Kevin Chao | |
Chen, Yud | |
Chan, Diane |
Submitted to: Applied Engineering in Agriculture
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 5/8/2003 Publication Date: 7/1/2003 Citation: CHAO, K., CHEN, Y.R., CHAN, D.E. ANALYSIS OF VIS/NIR SPECTRAL VARIATIONS OF WHOLESOME, SEPTICEMIA, AND CADAVER CHICKEN SAMPLES. APPLIED ENGINEERING IN AGRICULTURE. 2003. Interpretive Summary: Poultry and poultry products have increased in popularity with U.S. consumers in recent years. Due to massive production of poultry and the inherent variability and complexity in individual birds, there are great challenges for improvement of the existing organoleptic inspection methods. Development of high speed and reliable inspection systems to ensure safe production of poultry during post-harvest processing has become an important issue, as the public is demanding assurance of better and safer food. The Instrumentation and Sensing Laboratory, ARS, USDA, has developed a Vis/NIR spectroscopic system for on-line poultry carcass inspection. This system was proven to be effective in distinguishing between wholesome and unwholesome carcasses. To better understand how the carcasses can be differentiated, a further in-depth study of Vis/NIR spectra of poultry samples was conducted. One hundred and twenty chicken carcasses (40 wholesome, 40 septicemia, and 40 cadaver) were collected from Allen Family Foods, Cordova, Maryland. Spectral data were analyzed using chemometric techniques. Classification models were also built to separate poultry meat into individual classes. The best Vis/NIR classification model, using 9 principal components and a linear discriminant function, correctly classified 100%, 90.0%, and 92.5% of the whole samples for wholesome, septicemia, and cadaver categories, respectively. This information is useful to the Food Safety and Inspection Service (FSIS), and poultry equipment and processing plants. Technical Abstract: The Instrumentation and Sensing Laboratory, ARS, USDA, has developed a Vis/NIR spectroscopic system for on-line poultry carcass inspection. This system was proven to be effective in distinguishing between wholesome and unwholesome carcasses. To better understand how the carcasses can be differentiated, a further in-depth study of Vis/NIR spectra of poultry samples was conducted. Results showed that Vis/NIR spectroscopy can be used to differentiate poultry samples more finely than merely between a wholesome category and a broadly inclusive unwholesome category. Using principal component analysis (PCA) and discriminant analysis, wholesome, septicemia, and cadaver chicken samples were differentiated from each other with high accuracy. The best Vis/NIR classification model, using 9 PCs and a linear discriminant function, correctly classified 100%, 90.0%, and 92.5% of the whole (skin and meat) samples for wholesome, septicemia, and cadaver categories, respectively. For skin only samples, similar models using 9 PCs resulted in lower accuracies. Examination of the PCA loadings for the whole samples suggested that the better discrimination of whole samples was dependent on spectral variation related to different forms of myoglobin present in the chicken meat, i.e. deoxymyoglobin, metmyoglobin, and oxymyoglobin. In particular, key wavelengths were identified at 540 and 585 nm, which have been identified as oxymyoglobin bands, for PCs 1 and 2; 485 nm, metmyoglobin, for PC 3; and 440 nm, deoxymyoglobin, for PC 8. |