Measurement of pork freshness by steady spatially-resolved spectroscopy

The objective of this work was to investigate the relationship between optical parameter of pork meat and meat freshness, and establish a fast non-invasive method to evaluate freshness. Based on principles of bio-photonics and steady spatially-resolved short wavelength near infrared spectroscopy, a multiple channel visible and near infrared spectrometer for determination of optical parameter was established, which could measure (or obtain) spectrum of effective attenuation coefficient during changes in pork meat freshness. In this work, the relationships between effective attenuation coefficient and traditional indexes, i.e. total volatile basic nitrogen (TVB-N) as an indicator of freshness, total plate count of bacteria and sensory indicators, were also investigated. The results showed that the variations in tissue structure influenced on scattering due to spoilage resulting in cells membrane damage and rupture; and effective attenuation coefficient of sample was significantly correlated to TVB-N value at 940 nm and 960 nm. The conclusion showed that the relationship between near infrared spectrometer and TVB-N value can be found to evaluate meat freshness.