Assessment of pork freshness based on changes in constituting chromophores using visible to near-infrared spectroscopy

摘要

Visible to near-infrared spectroscopy has been applied for non-invasive assessment of meat freshness. The measurementswere done at room temperature with non-frozen pork samples. The absorbance spectra of the main chromophores in meatincluding oxymyoglobin, water, fat, and protein were different enough to be identified spectrophotometrically. Thedecreasing trend in absorbance spectra of these components over time can be associated with freshness decay. We usedtwo configurations, fiber-optic probes and integrating sphere, to study their efficiency in meat quality evaluation. In theintegrated sphere configuration, the samples experienced an immediate smooth decrease of oxymyoglobin absorbancearising from loss of superficial freshness, while degradation kinetics of water, fat and protein absorbance were detectedafter about 2.5 hours. In the fiber-optic configuration capable for sensing up to 570-μm depth, the drop in oxymyoglobinabsorbance started after 4.5 hours which would affect directly the color of sample associated with freshness.