Fluorescence Characteristics of Wholesome and Unwholesome Chicken Carcasses

Abstract

Each chicken carcass intended for U.S. consumers is mandated to be inspected by Food Safety and Inspection Service (FSIS) inspectors for its wholesomeness at the processing plants. Fluorescence responses of wholesome and unwholesome chicken carcasses were characterized and further evaluated for potential on-line applications for detection and classification of wholesome and unwholesome chicken carcasses. For this study, unwholesome chicken carcasses included cadaver and those with disease conditions such as airsacculitis and septicemia. Fluorescence characteristics from the epidermal layers in the breast areas of chicken carcasses were dynamic in nature. Emission peaks and ridges (maxima) were observed at 386, 444, 472, 512, and 554 nm and valleys (minima) were observed at 410, 460, 484, and 538 nm. One of the major factors affecting the line shapes of fluorescence responses from chicken carcass skin layers was absorption by hemoglobin. With the use of the normalized ratio spectra (NRS) approach, oxyhemoglobin was shown to be a major constituent in chicken carcasses affecting the fluorescence emission line shapes. Subtle line shape changes in the NRS also provided a qualitative means by which to assess the minute differences in oxy- and deoxyhemoglobin compositions perturbed by poultry diseases such as septicemia and airsacculitis. With the use of simple fluorescence band ratios as a multivariate model, wholesome and unwholesome chicken carcasses were correctly classified with 97.1% and 94.8% accuracies, respectively. On-line implementation of fluorescence techniques for the assessment of chicken carcass wholesomeness appears promising.

COLLAGEN AS IN VIVO QUANTITATIVE FLUORESCENT BIOMARKERS OF ABNORMAL TISSUE CHANGES

“…Major obstacles in this respect are nonadditive signals of several°uorophores in one solution due to their mutual absorption and signal di®usion, high turbidity of biological tissues, their axial and radial heterogeneousness for the light beam and, therefore, nonmonotonic dependence of the resulting°uoroscence intensity from a°uorophore's concentration. 4,5 In a living organism, controlled variation of concentration of only one endogenous°u orophore is impossible without changing of concentrations of others, 6 which could be a way to draw up calibrating spectra directly. This fact presents just another obstacle for the researcher.…”

Versatile multispectral microscope based on light emitting diodes

“…For highly fluorescent samples, and when studying optical properties in the UV region, even the wavelength of the excitation light source must be selected (discretized) with an additional monochromator to separate reflectance from fluorescence. 12 The optical efficiency (photon economy) is usually poor in these setups, since light is lost every time the beam is divided. The area studied can be rather large, and the samples must be of a considerable size.…”