Non-destructive predictability of hen egg composition by means of computer tomography in the function of applied scanning parameters and number of eggs examined simultaneously – methodological study

Abstract

In the present study scanning of 120 hen eggs was carried out by computer tomography (CT) at different technical parameters (different current intensity and tube voltage) and at different arrangement of eggs (eggs in egg holders and trays) in order to find the best accuracy of prediction in the determination of different egg components (albumen, yolk and shell) in intact eggs. Eighteen series of CT scans were made from all of the experimental eggs (nine different technical parameters in two types of arrangement) using overlapping 3 mm slice thickness on a Siemens Somatom Emotion 6 multislice CT scanner. Due to the applied arrangements two and five eggs were scanned simultaneously in egg holders and trays, respectively. On the CT images obtained the volume of the albumen, yolk and shell was determined by a self-developed egg-separation and segmentation software. Using the data obtained the ratio of the volume of these egg components to the volume of the whole eggs was calculated. After the CT measurements eggs were broken and their albumen, yolk and shell weight was measured and then their ratio to the whole egg weight was calculated. Between the CT predicted and measured egg component ratios Pearson correlations were calculated. The effect of the applied scanning parameters (current intensity and tube voltage) and the number of eggs examined simultaneously on the observed correlations was examined by Multivariate Analysis of Variance. Based on the results it was established that the simultaneous scanning of two eggs in the egg holders resulted in significantly higher correlations than the simultaneous scanning of five eggs in the egg trays. The reason of this could be the better resolution of the CT scans, when only two eggs are scanned simultaneously, instead of five. Namely, an egg is represented by more pixels (CT image elements) in this case and, therefore, the separation of the anatomical structures is more exact by the edge detecting algorithm. The use of the different scanning parameters did not result notable differences of the correlations.