Detection of Free-Range Chicken Egg Freshness using a Portable Near-Infrared Spectrometer at Different Egg Orientations

- Egg quality in terms of freshness for unfertilized free range chicken eggs was investigated in the study using a portable near-infrared spectrometer operating at 900 nm to 1700 nm. The egg freshness is commonly quantified based on the Haugh unit which is time consuming and destructive. Near-infrared spectroscopy can be used to assess the quality of eggs at the various stages of the supply chain. The portable near infrared spectrometer operating in reflectance mode was used to scan the egg sample in vertical and horizontal position. The result showed that the highest classification accuracy was from the free-range chicken egg obtained from the BPSU farm with a cross-validation accuracy of 68.20% and a test accuracy of 63.60 %. Position 1 (vertical) gives the highest accuracy and it is attributed to the changes in air cell height during ageing which affects the spectral data obtained from the egg samples. The spectra were pretreated using Savitzky Golay 1st derivative with a smoothing point =7 and analyzed using stepwise discriminant analysis. The result showed the potential of the portable near infrared spectrometer to predict the freshness of free-range chicken egg real time. It can be implemented in online grading and can be a nondestructive technique for detecting egg freshness.